Glaucoma Surgery Research Papers - Academia.edu (original) (raw)

We propose an integrated model of aqueous outflow control that employs a pump-conduit system in this article. Our model exploits accepted physiologic regulatory mechanisms such as those of the arterial, venous, and lymphatic systems. Here, we also provide a framework for developing novel diagnostic and therapeutic strategies to improve glaucoma patient care. In the model, the trabecular meshwork distends and recoils in response to continuous physiologic IOP transients like the ocular pulse, blinking, and eye movement. The elasticity of the trabecular meshwork determines cyclic volume changes in Schlemm's canal (SC). Tube-like SC inlet valves provide aqueous entry into the canal, and outlet valve leaflets at collector channels control aqueous exit from SC. Connections between the pressure-sensing trabecular meshwork and the outlet valve leaflets dynamically control flow from SC. Normal function requires regulation of the trabecular meshwork properties that determine distention and recoil. The aqueous pump-conduit provides short-term pressure control by varying stroke volume in response to pressure changes. Modulating TM constituents that regulate stroke volume provides long-term control. The aqueous outflow pump fails in glaucoma due to the loss of trabecular tissue elastance, as well as alterations in ciliary body tension. These processes lead to SC wall apposition and loss of motion. Visible evidence of pump failure includes a lack of pulsatile aqueous discharge into aqueous veins and reduced ability to reflux blood into SC. These alterations in the functional properties are challenging to monitor clinically. Phasesensitive OCT now permits noninvasive, quantitative measurement of pulse-dependent TM motion in humans. This proposed conceptual model and related techniques offer a novel framework for understanding mechanisms, improving management, and development of therapeutic options for glaucoma.

- by and +1
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- Biomechanics, Nitric oxide (Vascular biology), Glaucoma, Intraocular Pressure

Minimally invasive glaucoma surgery (MIGS) has become increasingly popular as a step in the management pathway of open angle glaucoma. Due to the relative novelty of these devices, there remains some paucity of evidence relating to their long-term efficacy and safety, and this can make comparison between these techniques somewhat complex. This review article aims to guide clinical decision making by providing the latest evidence on the comparative efficacy of current iterations of minimally invasive glaucoma surgery. A literature review was conducted to identify the most significant recent evidence to support the safety and efficacy of the various forms of minimally invasive glaucoma surgery. Included studies provided efficacy and safety data on a variety of minimally invasive glaucoma surgery methods. The PubMed database was searched and a total of 484 studies, published between 2015 and 2020 were identified, of which 27 were included. The studies indicate that most available forms of minimally invasive glaucoma surgery show statistically significant efficacy in terms of intraocular pressure reduction and improvement in medication burden, while maintaining an acceptable safety profile.

- by Mary Ma
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- Surgery, Minimally Invasive Surgery, Glaucoma Surgery, Trabeculectomy

In this clinical study hyperbaric ropivacaine in spinal anaesthesia for lower limb and hip surgery was evaluated and results obtained were compared with those using hyperbaric bupivacaine. Methodology: Two hundred patients scheduled for lower limb and hip surgery were randomly divided into two groups of 100 patients each. These patients received a spinal injection of either 3ml (15mg) of 0.5% hyperbaric ropivacaine or 3ml (15mg) of 0.5% hyperbaric bupivacaine using 25G Quincke type spinal needle. The parameters studied were -onset and total duration of sensory block, onset and total duration of motor block, quality of intraoperative anaesthesia, hemodynamic alterations, and any intraoperative and postoperative complications. Results: The mean onset of sensory block (6±1.3min vs. 3±1.1min; p value<0.05) and motor block (13±1.6min vs. 9±1.3min; p value< 0.05) was significantly slower in ropivacaine group as compared to bupivacaine group. The total duration of sensory block was significantly shorter in ropivacaine group (160±12.9min) than in bupivacaine group (260±16.1min; p value <0.05). The mean duration of motor block was also shorter in ropivacaine group compared to bupivacaine group (126±9.2min vs. 174±12.6min; p value<0.05). Conclusion: The quality of anaesthesia was excellent in both the groups. In conclusion, a solution of ropivacaine (hyperbaric) can be used for spinal anaesthesia and is comparable with hyperbaric bupivacaine in terms of quality of block, but has shorter recovery profile.

Glaucoma is a silent thief of sight which is characterized by elevated intraocular pressure, slow vision loss leads to permanent blindness. Although the disease is incurable but its symptoms can be minimized therefore early detection of the disease is essential. It is a very expensive process to detect the disease using the modern tools as a result of which we are developing a methodology for detection such that it is affordable by all the sections of the society, also it can be detected at the early stage and prevention can be taken. Hence, proposing a novel methodology for primary glaucoma detection by developing software algorithms in Matlab, which focuses on automated detection of glaucoma from fundus images using CDR calculation.

Objective: To evaluate the change of biomechanical properties of the trabecular meshwork (TM) and configuration of collector channels (CC) by high-resolution optical coherence tomography (HR-OCT) induced by Schlemm's canal (SC) dilation. Methods: The anterior segments of two human eyes were divided into four quadrants. One end of a specially designed cannula was placed in SC and the other end connected to a perfusion reservoir. HR-OCT provided three-dimensional (3D) volumetric and two-dimensional (2D) cross-sectional imaging permitting assessment of the biomechanical properties of the TM. A large fluid bolus was introduced into SC. Same-sample, pre and post deformation and disruption of SC and CC lumen areas were analyzed. Results: Morphologic 3D reconstructions documented pressure-dependent changes in lumen dimension of SC, CC, and circumferential intrascleral channels. 2D imaging established volumetric stress-strain curves (elastance curves) of the TM in quadrants. The curves of TM elastance shift to the right with an increase in pressure-dependent steady-state SC area. After a bolus disruption, the SC area increased, while the CC area decreased. Conclusion: Our experimental setup permits the study of the biomechanical properties of TM by examining elastance, which differs segmentally and is altered by mechanical expansion of SC by a fluid bolus. The study may shed light on mechanisms of intraocular pressure control of some glaucoma surgery.

- by Murray Johnstone
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- Biomechanics, Glaucoma, Shear Stress, Glaucoma Surgery

Objective-This study was carried out to evaluate the usefulness of endoscopy for examination of the anterior and posterior segments of the glaucomatous eyes. Animals: Fifteen dogs. Methods: Ocular examination was done using endoscopic probe (8.5mm diameter, Eickemeyer video endoscope unit supplied with halogen light source 150 watt (vetlux), Germany). The animals were sedated through intravenous injection of Xylazine (1mg/Kg body weight, ADWIA, Egypt). Surface corneal anesthesia was achieved by local application of Benox® (Benoxinate Hydrochloride 4mg, EIPICO, Egypt) to the eye under investigation. After sedation, the endoscopic probe was applied on the cornea and videos were monitored on the laptop and diagnostic images were captured and processed. Results: Primary open angle glaucoma was diagnosed in 2 cases. Goniodysgenesis with closure of the iridocorneal angle (ICA) by an iris like sheet was seen in 2 cases. Abnormal thickening of the pectinate ligament with closure of the ICA was observed in one case. Lens induced glaucoma was the most common type of the glaucoma seen in the presented cases (10 cases); phacomorphic glaucoma due to lens displacement was diagnosed in 5 cases, phacoanaphylactic glaucoma secondary to cataractous lens was diagnosed in 3 cases while pupillary block glaucoma (due to swelling of the cataractous lens) was seen in 2 cases. Conclusion: endoscopy is non invasive technique for diagnosis of glaucoma in dogs in which interior visualization of the eye is impossible such in cases with corneal edema and cataract. [Abd-Elhamid M.A, Ali K.M and Ayman A. Mostafa. Endoscopic evaluation for the anterior and posterior segment of the eye: A new and useful technique for diagnosis of glaucoma in dogs. Life Sci J 2014;11(11):233-237]. (ISSN:1097-8135). http://www.lifesciencesite.com. 33

- by Ayman Mostafa
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- Glaucoma Surgery

Implante de Baerveldt en pars plana en cirugía de glaucoma Baerveldt pars plana implant in glaucoma surgery Introducción El dispositivo de drenaje para el glaucoma (DDG) Baerveldt (Advanced Medical Optics, Inc., Santa Ana, CA) fue descrito por primera vez en la década de 1990 por M.A. Lloyd, G. Baerveldt, et al. 1. Consta de un tubo de silicona no valvulado (TSNV) de 0,63 mm de diámetro externo y 0,30 mm de calibre, conectado a un plato de silicona (PS), que actualmente está disponible en dos tamaños (250 mm 2 y 350 mm 2) con similares eficacias y resultados postoperatorios 2. Tiene un reborde anterior con dos agujeros para suturas, separados por una sobreelevación de 1 mm para la entrada del TSNV. El espesor, de 0,84 mm, permite cierta flexibilidad y rigidez a la vez, cualidades necesarias para su correcta implantación. El PS está fenestrado con cuatro agujeros que permiten al tejido fibroso crecer entre el muro escleral y subconjuntival, lo que reduce la altura de la ampolla fibrosa y disminuye las posibles limitaciones de motilidad ocular. Además, el DDG, compuesto de polidimetilsiloxano o polimetilmetacrilato (PMMA), está impregnado en bario, lo que permite su identificación radiográfica 3. La versión para pars plana (PP), de 250 mm 2 o de 350 mm 2 , lleva un pequeño plato epiescleral incorporado al TSNV con una cánula angulada 90° de 7 mm de longitud que se introduce en la cavidad vítrea a través de una esclerotomía (Figura 1).

- by Maria Iglesias and +1
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- Ophthalmology, Glaucoma Surgery

Purpose: To compare intraocular pressure (IOP) reduction and to develop a predictive surgery calculator based on the results between trabectome-mediated ab interno trabeculectomy in pseudophakic patients versus phacoemulsification combined with trabectome-mediated ab interno trabeculectomy in phakic patients.
Methods: This observational surgical cohort study analyzed pseudophakic patients who received trabectome-mediated ab interno trabeculectomy (AIT) or phacoemulsification combined with AIT (phaco-AIT). Follow up for less than 12 months or neovascular glaucoma led to exclusion. Missing data was imputed by generating 5 similar but non-identical datasets. Groups were matched using Coarsened Exact Matching based on age, gender, type of glaucoma, race, preoperative number of glaucoma medications and baseline intraocular pressure (IOP). Linear regression was used to examine the outcome measures consisting of IOP and medications.
Results: Of 949 cases, 587 were included consisting of 235 AIT and 352 phaco-AIT. Baseline IOP between groups was statistically significant (p≤0.01) in linear regression models and was minimized after Coarsened Exact Matching. An increment of 1 mmHg in baseline IOP was associated with a 0.73±0.03 mmHg IOP reduction. Phaco-AIT had an IOP reduction that was only 0.73±0.32 mmHg greater than that of AIT. The resulting calculator to determine IOP reduction consisted of the formula -13.54+0.73 × (phacoemulsification yes:1, no:0) + 0.73 × (baseline IOP) + 0.59 × (secondary open angle glaucoma yes:1, no:0) + 0.03 × (age) + 0.09 × (medications).
Conclusions: This predictive calculator for minimally invasive glaucoma surgery can assist clinical decision making. Only a small additional IOP reduction was observed when phacoemulsification was added to AIT. Patients with a higher baseline IOP had a greater IOP reduction.

- by Nils Loewen and +2
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- Glaucoma, Glaucoma Surgery, MIGS, Trabectome

Medical Glaucoma is a major cause of blindness. It affect quality of life of patients. So the present study was carried out in ESI Hopital, Jaipur with the aim to assess quality of life of glaucoma patients as per WHOQOL-Bref. Along with assessment of quality of life of patients various socio-demographic and clinical associates of this quality of life was also found. It was observed that quality of life of glaucoma patients was lowered in all four domains i.e. Physical, Mental, Social and Environmental. Among socio-demographic variables, quality of life was not found to be associated with sex and marital status but it was found more poorer in elder age groups and low socio-economic status. Among clinical variables its quality of life of glaucoma patients was not found to be associated with papillary reaction, Anterior chamber depth (ACD), type of glaucoma and duration of glaucoma but it was found more poorer in glaucoma patients with pain, congestion and defective visual equity. Quality of life was significantly lowered in sever glaucoma. Glaucoma patients should be educated to realize the severity of the disease and importance of the adherence to daily treatment.

- by Medical Journal IMJ Health
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- Quality of life, Glaucoma, Glaucoma Surgery, WHOQOL-BREF

Glaucoma is a leading cause of blindness worldwide and results from damage to the optic nerve. Currently, intraocular pressure is the only treatable risk factor. Changes in aqueous outflow regulate pressure; regulation becomes abnormal in glaucoma. From inside the eye aqueous flows out through the trabecular meshwork into a venous sinus called Schlemm's canal, next into collector channels and finally returns to the episcleral vessels of the venous system. The location of aqueous outflow regulation is unknown. Ex vivo and in vivo studies implicate both pressure-dependent trabecular tissue motion and tissues distal to Schlemm's canal in regulation of aqueous outflow. Technologies have not previously been available to study these issues. New ex vivo imaging in human eyes identifies hinged flaps or leaflets at collector channel entrances using a high-resolution spectral domain optical coherence tomography (SD-OCT) platform. The hinged flaps open and close in synchrony with pressure-dependent trabecular meshwork motion. The SD-OCT platform images from the trabecular meshwork surface while experimentally changing transtrabecular pressure gradients. New in vivo imaging in human eyes uses a motion sensitive technology, phase-sensitive OCT to quantitate real-time pulse-dependent trabecular tissue motion as well as absence of such motion when aqueous access to the outflow system is blocked. The recent studies suggest that aqueous outflow regulation results from synchronous pressure-dependent motion involving a network of interconnected tissues including those distal to Schlemm's canal. The new imaging technologies may shed light on glaucoma mechanisms and provide guidance in the management of medical, laser and surgical decisions in glaucoma.

- by Murray Johnstone and +3
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- Glaucoma, Intraocular Pressure, Glaucoma Surgery, Trabecular Meshwork

Purpose: Nonsurgical glaucoma therapy reduces intraocular pressure (IOP) by a percentage that is similar for most patients. Recently introduced microincisional glaucoma surgeries are different because they remove the trabecular meshwork that constitutes the primary resistance to outflow. We hypothesized that because of this, the resulting postoperative IOP, rather than the relative reduction, had to be independent of glaucoma severity. We applied a glaucoma index (GI) to analyze outcomes of trabectome surgery combined with phacoemulsification (PT) by glaucoma severity. Methods: Only PT with 12 month follow up and no other surgeries were included. GI incorporated preoperative IOP, medications (meds) and visual field (VF). Baseline IOP was divided into 4 groups, <20 mmHg, 20-29 mmHg, 30-39 mmHg, and above 40 and assigned with 1 to 4 points. Meds was divided into 4 groups: ≤1, 2, 3, or ≥4, and assigned values of 1 to 4. VF was separated into 4 groups with points from 1 to 4: mild, moderate, advanced and end stage. GI was then defined as VF*meds*IOP and separated into GI1: <3, GI2: 3-5, GI3: 6-11 and GI4 ≥12. We tested for an association between GI group and IOP reduction at one year as well as age, gender, race, diagnosis, cup to disc (C/D) ratio, and Shaffer grade, using linear regression. Results: Phaco-AIT was analyzed in 498 cases. These patients had a mixed indication of a visually significant cataract and the need to lower IOP or an interest in lowering the number of glaucoma medications. Mean IOP reduction after one year was 2.9±4.4, 3.6±5.0, 3.9±5.3, and 9.2±7.6 mmHg for GI groups 1 to 4, respectively. Linear regression showed that IOP reduction was associated with GI group after adjusting for age, diagnosis, and visual acuity (logMAR). For patients that differ in GI group by 1, patients in a higher GI group had an IOP reduction greater by 1.7±0.2 mmHg than patients in a lower GI group. Survival rate at 12 months was 98%, 93%, 96% and 88% for GI groups 1 to 4. Log-rank test suggested a statistically significant difference in survival distributions between GI groups. Conclusion: Despite a less absolute indication to lower IOP compared to patients undergoing trabectome surgery as a stand-alone procedure, a substantial IOP reduction was seen that was larger in subjects with more advanced glaucoma. This matches the concept that the trabecular meshwork is the primary impediment to outflow and its ablation benefits those eyes relatively more than in mild glaucoma. Higher GI groups are expected to have a greater reduction of IOP and appear to be similarly suited to trabectome surgery as a first step towards pressure control.

- by Nils Loewen and +3
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- Glaucoma, Minimally Invasive Surgery, Glaucoma Surgery, Glaucoma Microsurgery

Trabecular meshwork (TM) motion abnormality is the leading cause of glaucoma. With technique limitations, how TM moves is still an enigma. This study describes a new laboratory platform to investigate TM motion responses to ocular transients in ex vivo eyes. The anterior segments of human cadaver and primate eyes were mounted in a perfusion system fitting. Perfusion needles were placed to establish mean baseline pressure. A perfusion pump was connected to the posterior chamber and generated an immediate transient pressure elevation. A phase-sensitive optical coherent tomography system imaged and quantified the TM motion. The peak-to-peak TM displacements (ppTMD) were determined, a tissue relaxation curve derived, and a time constant obtained. This study showed that the ppTMD increased with a rise in the pulse amplitude. The ppTMD was highest for the lowest mean pressure of 16 mmHg and decreased with mean pressure increase. The pulse frequency did not significantly change ppTMD. With a fixed pulse amplitude, an increase in mean pressure significantly reduced the time constant of recoil from maximum distension. Our research platform permitted quantitation of TM motion responses to designed pulse transients. Our findings may improve the interpretation of new TM motion measurements in clinic, aiding in understanding mechanisms and management.

- by Murray Johnstone
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- Biomechanics, Nitric oxide, Glaucoma, Shear Stress

Purpose: To compare the effect on intraocular pressure (IOP) of phacoemulsification combined with viscosynechialysis and trabe-culotomy with that of phacoemulsification combined with trabecu-lectomy in eyes with primary angle-closure... more

- by Amani E Badawi
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- Cataract surgery, Glaucoma Surgery

Purpose To evaluate retrobulbar blood flow characteristics of glaucoma suspects with glaucomatous optic disc appearance (GODA) in comparison to healthy control group (CG) and primary open angle glaucoma patients (POAG) and assess the effect of age. Methods 145 patients from a single glaucoma clinic were enrolled and classified into two diagnostic groups (GODA and POAG). Third group of subjects consisted of 67 age matched individuals (CG). Retrobulbar blood velocity measurement in central retinal artery was performed using color Doppler imaging (CDI). CDI images were processed in custom software leading a range of parameter estimates from a continuous waveform signal. The effect of age on the estimated parameters was evaluated with the stepwise forward regression and ANCOVA in which age was used as a continuous factor. One-way ANOVA was used to test for the differences in the CDI parameters between the three considered groups. Correlation between restive index (RI) and pulsatility index (PI) was assessed with a bilinear fitting guaranteeing no discontinuities in RI intercept estimate. Fisher test was used to assess the applicability of a bilinear PI/RI relationship, while the statistics of the RI intercept estimate were evaluated using the bootstrap. Results ANCOVA showed significant interaction between age and group (p<0.05) for five out of nine considered CDI parameters. The RI intercept for CG and GODA groups was 0.602± 0.047, and 0.574±0.044 respectively, while the RI intercept of 0.934±0.066 was found for the POAG.

- by Patrycja Krzyzanowska-Berkowska and +2
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- Glaucoma Surgery, Optic Nerve Head Imaging

Purpose To assess the efficacy and safety of the XEN Gel Stent in patients with primary open-angle glaucoma. Materials and methods Twenty eyes of 17 patients (6 males, 11 females) with primary open-angle glaucoma were implanted with XEN Gel Stent. The following data were ascertained in each participant at baseline and at 1, 3, 6, 9 and 12 months following implanting procedure: intraocular pressure, number of anti-glaucoma medications, retinal sensitivity (PS 24/2 w/w), pattern electroretinogram (ISCEV standard), as well as the number of complications. Results The mean intraocular pressure reduction in a 1-year follow-up was 18% (21.56 vs. 17.69 mmHg, p \ 0.001). The mean number of anti-glaucoma medications was reduced from 3.2 to 1.6 (p = 0.001). The PERG parameters at baseline and at 12 months postoperatively included a stable amplitude of P50 (2.55 lV vs. 2.65 lV, p = 0.024) and N95 (3.45 lV vs. 3.38 lV, p = ns) waves. The delta N95 and delta P50 amplitudes remained stable over the follow-up period (p = ns). The mean deviation (MD) of PS 24/2 was-6.54 dB vs.-8.43 dB, p = ns, whereas the pattern standard deviation (PSD) was 6.18 dB vs. 6.91 dB, p = ns. Transient hypotony within the first postoperative week occurred in 18 eyes (90%), whereas hyphema occurred in two eyes (10%). Needle revision of a filtration bleb was performed in five eyes (25%). Conclusions The XEN Gel Stent enables significant reduction in intraocular pressure with very low complication rates. It ensures a stabilization of the retinal function as established with the PERG.

- by Michal Post and +1
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- Ophthalmology, Electrophysiology, Xen, Glaucoma Surgery

CONCLUSION: Diabetes mellitus has a clear negative effect upon the color vision in both qualitative as assessed by Farnsworth FD-15 test and quantitative manner as assessed by Ishihara PIP test leading to loss of color vision perception with a varying degree in relation to the type of diabetes and disease duration from patients medical history, degree of retinopathy , presence of maculopathy by Fundus examination + FFA and the increased macular thickness by OCT when compared to normal healthy individuals.

- by Waleed Ghobashy and +2
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- Ophthalmology, Cataract (Ophthalmology), Refractive Surgery, Diabetic Retinopathy

Purpose
The aim of the study was to evaluate the effi cacy and safety of decapsulation of the fi brous capsule
around the valve body versus valve reimplantation in another site in refractory glaucoma cases.
Patients and methods
We studied 25 cases with refractory glaucoma that had been implanted with an Ahmed
glaucoma valve; their intraocular pressure (IOP) was greater than 21 mmHg and had undergone
additional maximum topical antiglaucoma therapy. Patients were divided into two groups
according to the surgical treatment that had been performed: group I included 12 eyes that
had been treated by surgical decapsulation of the cyst around the valve body without removal
of the valve and group II included 13 eyes treated by removal of the valve and reimplantation
in another quadrant of the eye.
Results
Of the 25 patients included in the study, 15 were male and 10 were female, with a mean
age of 19.2 ± 9.2 years in group I and 22.1 ± 10.3 years in group II. Recurrent congenital
glaucoma was the most common preoperative diagnosis in both groups (50 and 53.8% in
groups I and II, respectively). There was no statistically signifi cant difference between the two
groups regarding preoperative patient demographic characteristics (P < 0.05). The surgical
results revealed that the mean operation time was signifi cantly lower in group I than in group II
(30 ± 12 and 45 ± 13.5 min, respectively; P = 0.023). However, there were no statistically
signifi cant differences in the success (complete and partial) and failure rates between the
two groups (P < 0.05). There was marked reduction in IOP from preoperative values in both
groups but there were no signifi cant differences in IOP levels between the two groups over
the follow-up visits. Tube-related complications occurred in group II only and included corneal
tube touch in one (7.7%) case and erosion of the tube covering in two (15.4%) cases. One
of them developed endophthalmitis and then lost the perception of light (PL) and ended in
phthisis bulbi. Recurrence of encapsulation occurred more in group I (three cases, 25%) than
in group II (two cases, 15.4%), after a mean postoperative time of 23 ± 2 weeks. The incidence
of valve re-encapsulation was statistically insignifi cant between the two groups (P = 0.09).
Conclusion
Both surgical techniques were effective in controlling IOP in cases with encapsulated Ahmed
valve; however, the decapsulation technique was simpler with shorter operation time and no
probability for tube-related complications. Although the other technique of valve reimplantation
had a longer operation time and more tube-related complications, it was associated with less
incidence of re-encapsulation. However, larger multicenter studies with longer follow-up are
needed for validation of these treatment strategies.
Keywords:
ahmed glaucoma valve, decapsulation, refractory glaucoma

- by salah almosalamy
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- Glaucoma Surgery

PURPOSE: To stratify outcomes of trabectome-mediated ab interno trabeculectomy (AIT) by glaucoma severity using a simple and clinically useful glaucoma index. Based on prior data of trabectome after failed trabeculectomy, we hypothesized that more severe glaucoma might have a relatively more reduced facility compared to mild glaucoma and respond with a larger IOP reduction to trabecular meshwork ablation. METHODS: Patients with primary open angle glaucoma who had undergone AIT without any other same session surgery and without any second eye surgery during the following 12 months were analyzed. Eyes of patients that had less than 12 months follow up or were diagnosed with neovascular glaucoma were excluded. A glaucoma index (GI) was created to capture glaucoma severity based on visual field, number of preoperative medications, and preoperative IOP. Visual field (VF) was separated into 3 categories: mild, moderate, and advanced (assigned 1, 2, and 3 points, respectively). Preoperative number of medications (meds) was divided into 4 categories: ≤1, 2, 3 or ≥4, and assigned with a value of 1 to 4. Baseline IOP (IOP) was divided into 3 categories: 12-18 (Group 3) and >18 (Group 4). Linear regression was used to determine if there was an association between GI group and IOP reduction after one year or age, gender, race, diagnosis, cup to disc (C/D) ratio, and Shaffer grade. RESULTS: Out of 1340 patients, 843 were included in the analysis. The GI group distribution was GI1 = 164, GI2 = 202, GI3 = 260, and GI4 = 216. Mean IOP reduction after one year was 4.0±5.4, 6.4±5.8, 9.0±7.6, 12.0±8.0 mmHg for GI groups 1 to 4, respectively. Linear regression showed that IOP reduction was associated with GI group after adjusting for age, gender, race, diagnosis, cup to disc ratio, and Shaffer grade. Each GI group increase of 1 was associated with incremental IOP reductions of 2.95±0.29 mmHg. Success rate at 12 months was 90%, 77%, 77%, and 71% for GI groups 1 to 4. The log-rank test suggested significant differences between GI groups. CONCLUSION: A simple glaucoma index, GI, was created to capture glaucoma severity and a relative resistance to treatment. A higher GI was associated with a larger IOP reduction in trabectome surgery. This indicates that there is a role for AIT beyond mild glaucoma and ocular hypertension.

- by Nils Loewen and +4
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- Glaucoma, Glaucoma Surgery, Trabectome

We examined the role of common genetic variation in schizophrenia in a genome-wide association study of substantial size: a stage 1 discovery sample of 21,856 individuals of European ancestry and a stage 2 replication sample of 29,839 independent subjects. The combined stage 1 and 2 analysis yielded genome-wide significant associations with schizophrenia for seven loci, five of which are new (1p21.3, 2q32.3, 8p23.2, 8q21.3 and 10q24.32-q24.33) and two of which have been previously implicated (6p21.32-p22.1 and 18q21.2). The strongest new finding (P = 1.6 × 10(-11)) was with rs1625579 within an intron of a putative primary transcript for MIR137 (microRNA 137), a known regulator of neuronal development. Four other schizophrenia loci achieving genome-wide significance contain predicted targets of MIR137, suggesting MIR137-mediated dysregulation as a previously unknown etiologic mechanism in schizophrenia. In a joint analysis with a bipolar disorder sample (16,374 affected individuals a...

- by Vaughan Carr
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- Genetics, Bipolar Disorder, Face, Biological Sciences

Purpose To make an account of published implant-related complications (IRC) by a systematic review of the literature. Methods A systematic search of Pubmed and Scopus databases and Google Scholar engine was performed with selection criteria to detect papers on IRC. We excluded unrelated papers and reviewed selected ones. We considered papers that did not explicitly state about occurrence or not occurrence of IRC as non-IRC reporting. Main outcome measures were the number of papers reporting on complications, IRC, and types of IRC. Results After the search, selection, and addition, we studied 109 papers. Incidence of IRC was 4.5%, half required explantation. While 26 implant studies found IRCs (23%), 13 case reports on surgical complications, 8 (61.5%) of them reported IRC. Frequent complications were conjunctival erosion, blockage of the tube, migration to anterior chamber or damage to surrounding tissues. Conclusion Most papers did not report on IRC. Length or nature of studies may skew finding IRC. The incidence of IRC was 4.5%. Hard and sharp implants carry a greater risk of IRC and explantation.

- by The Ophthalmology Open Journal
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- Glaucoma Surgery

Aims: To review the trends in glaucoma procedural treatments from January 2009
to December 2017. Methodology: A retrospective search was carried out from the
operating theater and laser room records of the Eye Foundation Hospitals in Lagos,
Abuja, and Ijebu‑Imushin. Consecutive glaucoma procedures for each year from
January 2009 to December 2017 were recorded in the data sheet prepared for the
study. Data were analyzed using SPSS version 25. Results: From 2009 to 2017,
trabeculectomy had been decreasing in frequency from 117 to 65 (44%), except for
2015. The frequency of use of glaucoma drainage device (GDD) has been steadily
increasing from 1 in 2013 to 26 in 2017, but this is not statistically significant.
The frequency of cataract extraction with trabeculectomy reduced drastically from
20 in 2009 to 3 (566%) in 2014. Bleb review (BR) increased from 2 in 2009 to
18 (800%) in 2015, however, it dropped to 6 in 2017 (66%). Among the laser
procedures, transscleral cyclophotocoagulation (g‑probe) is commonly done. It
increased from 40 procedures in 2009 to 98 in 2014 (145%). There has been an
increase in laser trabeculoplasty from 15 in 2009 to 44 in 2013 (193%). Laser
iridotomy increased from 12 in 2009 to 26 in 2015 (116%). From 2009 to 2015,
there was an increase in glaucoma procedures and surgeries – 206 to 325 (58%)
but this declined by 27% from 2015 to 2017. Conclusion: Trabeculectomy is the
most performed procedure at our centers. This is followed by g‑probe and laser
trabeculoplasty. The rate of trabeculectomy is on the decrease, while the rate of
GDD is increasing. The laser procedures are also on the increase.
Keywords: Eye Foundation Hospital Group, glaucoma surgeries, trends, types

- by Tayo Bogunjoko
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- Public Health, Cornea, Paediatric Ophthalmology, Medical Retina

Intraocular pressure (IOP) is the only treatable risk factor in glaucoma, one of the world's leading causes of blindness. Mechanisms that maintain IOP within a normal range have been poorly understood in contrast to intrinsic mechanisms that regulate systemic blood pressure. Vessel walls experience continuous pulse-induced cyclic pressure and flow. Pressure-dependent wall stress and flow-dependent shear stress provide sensory signals that initiate mechanotransduction responses. The responses optimize vessel wall elasticity, compliance and lumen size, providing a feedback loop to maintain intrinsic pressure homeostasis. Aqueous humor is part of a vascular circulatory loop, being secreted into the anterior chamber of the eye from the vasculature, then returning to the vasculature by passing through the trabecular meshwork (TM), a uniquely modified vessel wall interposed between the anterior chamber and a vascular sinus called Schlemm's canal (SC). Since pressure in circulatory loops elsewhere is modulated by cyclic stresses, one might predict similar pressure modulation in the aqueous outflow system. Recent laboratory evidence in fact demonstrates that cyclic IOP changes alter aqueous outflow while increasing cellularity and contractility of TM cells. Cyclic changes also lead to alterations in gene expression, changes in cytoskeletal networks and modulation of signal transduction. A new technology, phase-based optical coherence tomography, demonstrates in vivo pulse-dependent TM motion like that elsewhere in the vasculature. Recognition of pulse-dependent TM motion provides a linkage to well-characterized mechanisms that provide pressure homeostasis in the systemic vasculature. The linkage may permit unifying concepts of pressure control and provide new insights into IOP homeostatic mechanisms.

- by Murray Johnstone
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- Glaucoma, Intraocular Pressure, Glaucoma Surgery, Aqueous Outflow

Purpose: To describe an adjustable suture (AS) experimental model that allows for tightening, loosening and retightening of the suture tension in trabeculectomy. Methods: Standard trabeculectomy was performed in fifteen pig eyeballs. All pig eyes were tested twice: one test with conventional suture in both flap’s corners (conventional suture group) and another test with a conventional suture at one corner and an adjustable suture in the other corner (AS group). The order in which each test was performed was defined by randomization. Intraocular pressure was measured at three time points: T1) when the knots were tightened; T2) when the AS was loosened or the conventional knot was removed; and T3) when the AS was retightened in the AS group or five minutes after the knot removal in the conventional suture group.
Results: The mean Intraocular pressure was similar between the two groups at time point 1 (p=0.97). However, significant Intraocular pressure differences were found between eyes in the conventional and adjustable suture groups at time points 2 (12.6 ± 4.2 vs 16.3 ± 2.3 cmH2O, respectively, p=0.006) and 3 (12.2 ± 4.0 vs 26.4±1.7cmH2O,respectively;p=0.001).Whiletheconventionaltechniqueallowed only Intraocular pressure reduction (following the knot removal; T2 and T3), the AS technique allowed both Intraocular pressure reduction (T2) and elevation (T3) through the management (loosening and retightening) of the suture. conclusion: This experimental model provides an effective noninvasive posto- perative mechanism of suture tension adjustment.

- by Daniel Meira Freitas
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- Ophthalmology, Surgery, Glaucoma, Glaucoma Surgery
- by Michal Post
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- Ophthalmology, Medicine, Macular Degeneration, Optic Nerve

Purpose: To compare the results of trabeculectomy with subconjunctival Bevacizumab and 5-Fluorouracil (5-FU); with trabeculectomy with 5-FU alone; in terms of intraocular pressure (IOP) lowering, bleb formation, and complications, in the... more

- by Sana Nadeem
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- Glaucoma, Glaucoma Surgery

We report the use of a high-resolution optical coherence tomography (OCT) imaging platform to identify and quantify pressure-dependent aqueous outflow system (AOS) tissue relationships and to infer mechanical stiffness through examination of tissue properties in ex vivo human eyes. Five enucleated human eyes are included in this study, with each eye prepared with four equal-sized quadrants, each encompassing 90 degrees of the limbal circumference. In radial limbal segments perfusion pressure within Schlemm's canal (SC) is controlled by means of a perfusion cannula inserted into the canal lumen, while the other end of the cannula leads to a reservoir at a height that can control the pressure in the can-nula. The OCT system images the sample with a spatial resolution of about 5 μm from the trabecular meshwork (TM) surface. Geometric parameters are quantified from the 2D OCT images acquired from the sample subjected to controlled changes in perfusion pressures; parameters include area and height of the lumen of SC, collector channel entrances (CCE) and intrascleral collector channels (ISCC). We show that 3D OCT imaging permits the identification of 3-D relationships of the SC, CCE and ISCC lumen dimensions. Collagen flaps or leaflets are found at CCE that are attached or hinged at only one end, whilst the flaps are connected to the TM by cylindrical structures spanning SC. Increasing static SC pressures resulted in SC lumen enlargement with corresponding enlargement of the CCE and ISCC lumen. Pressure-dependent SC lumen area and height changes are significant at the 0.01 levels for ANOVA, and at the 0.05 for both polynomial curves and Tukey paired comparisons. Dynamic measurements demonstrate a synchronous increase in SC, CCE and ISCC lumen height in response to pressure changes from 0 to 10, 30 or 50 mm Hg, respectively, and the response time is within the 50-millisecond range. From the measured SC volume and corresponding IOP values, we demonstrate that an elastance curve can be developed to infer the mechanical stiffness of the TM by means of quantifying pressure-dependent SC volume changes over a 2 mm radial region of SC. Our study finds pressure-dependent motion of the TM that corresponds to collagen leaflet configuration motion at CCE

- by Murray Johnstone
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- Accommodation, Glaucoma, Intraocular Pressure, Glaucoma Surgery

Inter-individual variation in facial shape is one of the most noticeable phenotypes in humans, and it is clearly under genetic regulation; however, almost nothing is known about the genetic basis of normal human facial morphology. We therefore conducted a genome-wide association study for facial shape phenotypes in multiple discovery and replication cohorts, considering almost ten thousand individuals of European descent from several countries. Phenotyping of facial shape features was based on landmark data obtained from three-dimensional head magnetic resonance images (MRIs) and twodimensional portrait images. We identified five independent genetic loci associated with different facial phenotypes, suggesting the involvement of five candidate genes-PRDM16, PAX3, TP63, C5orf50, and COL17A1-in the determination of the human face. Three of them have been implicated previously in vertebrate craniofacial development and disease, and the remaining two genes potentially represent novel players in the molecular networks governing facial development. Our finding at PAX3 influencing the position of the nasion replicates a recent GWAS of facial features. In addition to the reported GWA findings, we established links between common DNA variants previously associated with NSCL/P at 2p21, 8q24, 13q31, and 17q22 and normal facial-shape variations based on a candidate gene approach. Overall our study implies that DNA variants in genes essential for craniofacial development contribute with relatively small effect size to the spectrum of normal variation in human facial morphology. This observation has important consequences for future studies aiming to identify more genes involved in the human facial morphology, as well as for potential applications of DNA prediction of facial shape such as in future forensic applications.

- by Adaikalavan Ramasamy
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- Genetics, Schizophrenia, Bipolar Disorder, Population Genetics

- by Stanley Carmel
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- Genetics, Schizophrenia, Bipolar Disorder, Population Genetics
- by Edward Haller
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- Glaucoma, Glaucoma Surgery

- by Michal Post
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- Ophthalmology, Electrophysiology, Xen, Clinical Sciences
- by Maja Bohac
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- Ophthalmology, Cataract (Ophthalmology), Eyelid Surgery, Glaucoma

Glaukoma adalah salah satu jenis penyakit mata dengan gejala yang tidak langsung, yang secara bertahap menyebabkan penglihatan pandangan mata semakin lama akan semakin berkurang sehingga hal ini dapat mengakibatkan kerusakan saraf... more

- by Evi Rafi'atus Saani
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- Optometry, History of Blindness/Visual Impairment, Blindness, Glaucoma

RESUMO O glaucoma maligno é uma doença caracterizada por pressão intraocular elevada com câmara anterior rasa na presença de iridectomia periférica patente. Na sua forma clássica, o glaucoma maligno é raro, e representa uma das mais sérias complicações da cirurgia fistulizante em pacientes com ângulo estreito ou glaucoma de ângulo fechado. O presente trabalho relata um caso de uma paciente do sexo feminino que desenvolveu crise de glaucoma por bloqueio ciliar (maligno) precipitada pela realização de curva tensional diária de pressão intraocular com tonômetro de contorno dinâmico. Descritores: Glaucoma de ângulo fechado; Tonometria ocular; Tomografia de coerência óptica; Lasers de estado solido; Relatos de casos ABSTRACT Malignant glaucoma is an entity characterized by intraocular pressure (IOP) with a shallow anterior chamber in the presence of a patent peripheral iridectomy. In its classic form, malignant glaucoma is rare but one of the most serious complications of fistulizing surgery in patients with narrow angle or angle closure glaucoma. In this case we have a female patient who developed crisis of ciliary block glaucoma (malignant) during performance of circadian IOP curve with dynamic contour tonometer.

- by Marcos A F Rego and +1
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- Ophthalmology, Cataract (Ophthalmology), Cataract surgery, Glaucoma

Purpose
The aim of the study was to evaluate the outcome of the surgical technique that utilizes freezedried
(lyophilized) amniotic membrane transplantation (AMT) with combined trabeculotomy–
trabeculectomy in cases of primary congenital glaucoma with respect to its effi cacy and
complications.
Patients and methods
This was a prospective controlled study that included 25 eyes of 19 patients with primary
congenital glaucoma. The patients were categorized into two groups: group I included 14
eyes that were treated with combined trabeculotomy–trabeculectomy with AMT and group
II included 11 eyes that were treated with combined trabeculotomy–trabeculectomy without
adjunctive (control group).
Results
Nineteen patients were included in the study: 13 were male and six were female. The mean
age was 6.2 ± 3.5 months and 5.7 ± 2.9 months in groups I and II, respectively; there were no
statistically signifi cant differences between groups I and II regarding the patient demographics
and preoperative characteristics. The surgical outcome of the two groups showed that absolute
success was achieved in 71.4% and qualifi ed success in 14.3% in group I, and in group II
absolute success was achieved in 45.5% and qualifi ed success in 27.2%. This difference was
highly signifi cant in terms of absolute success and signifi cant in terms of total success between
the two groups. The mean intraocular pressure (IOP) in this study was markedly decreased
from preoperative values in both groups during postoperative follow-up visits, with statistically
signifi cantly lower IOP in group I than in group II at all postoperative visits. The complications
encountered were hyphema in 28.6% of patients in group I and in 27.3% of patients in group II.
Shallow anterior chamber associated with hypotony occurred in 21.4 and 18.2% of patients in
groups I and II, respectively. One case in each group developed serous choroidal detachment.
Flat nonfunctioning bleb with high IOP occurred in 14.3% of patients in group I and in 27.3%
in group II. The complication rates were statistically insignifi cant between the two groups.
Conclusion
AMT-enhanced combined trabeculotomy–trabeculectomy appears to be an effective procedure
for the treatment of primary congenital glaucoma with better long-term control of IOP and
without added complications.
Keywords:
amniotic membrane, congenital glaucoma, trabeculectomy, trabeculotomy

- by salah almosalamy and +1
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- Pharmacology, Pharmacy, Glaucoma Surgery

Purpose: To establish the efficacy and safety of intravitreal bev-acizumab (Avastin) with panretinal photocoagulation (PRP) followed by Ahmed valve implantation in the treatment of neovascular glaucoma (NVG). Method: This prospective randomized study included 40 eyes of 40 patients with refractory NVG. Twenty eyes underwent Ahmed valve implantation with intravitreal bevacizumab (Avastin) (1.25 mg in 0.5 mL) and PRP and 20 eyes were managed by Ahmed valve and PRP (control group). The follow-up period was 18 months. Results: Complete success was defined as an intraocular pressure r21 mm Hg. Qualified success was considered when the above criteria were fulfilled but with additions of antiglaucoma topical medical treatment. The results revealed 95% total success (75% complete success and 20% qualified success) in the first group in which Avastin-augmented Ahmed valve was performed compared with 50% total success in the control group in which Ahmed valve implantation was performed alone (25% complete success and 25% qualified success). Conclusions: Intravitreal bevacizumab (Avastin) with PRP followed by Ahmed valve implantation appears to be effective in the management of NVG.

- by salah almosalamy and +2
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- Glaucoma Surgery

Ghost cell glaucoma (GCG) was first described in 1976. It is a type of a secondary open angle glaucoma, which occurs following long-standing vitreous hemorrhage. The ghost cells are rigid and less pliable than fresh red blood cells; therefore, they may cause direct obstruction of the trabecular meshwork and secondary increase in the intraocular pressure (IOP). This case report presents the diagnosis and management of a rare case of traumatic GCG after vitreous hemorrhage in a phakic child. Pars plana vitrectomy was done after unsuccessful medical therapy and the diagnosis was confirmed by cytopathology. Surprisingly, spontaneous resolution of the corneal blood staining occurred. The outcome in this case was favorable with controlled IOP in the affected eye.

- by Hind M Alkatan and +2
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- Trauma, Glaucoma Surgery, Ophthalmic Pathology

We propose an integrated model of aqueous outflow control that employs a pump-conduit system in this article. Our model exploits accepted physiologic regulatory mechanisms such as those of the arterial, venous, and lymphatic systems. Here, we also provide a framework for developing novel diagnostic and therapeutic strategies to improve glaucoma patient care. In the model, the trabecular meshwork distends and recoils in response to continuous physiologic IOP transients like the ocular pulse, blinking, and eye movement. The elasticity of the trabecular meshwork determines cyclic volume changes in Schlemm’s canal (SC). Tube-like SC inlet valves provide aqueous entry into the canal, and outlet valve leaflets at collector channels control aqueous exit from SC. Connections between the pressure-sensing trabecular meshwork and the outlet valve leaflets dynamically control flow from SC. Normal function requires regulation of the trabecular meshwork properties that determine distention and recoil. The aqueous pump-conduit provides short-term pressure control by varying stroke volume in response to pressure changes. Modulating TM constituents that regulate stroke volume provides long-term control. The aqueous outflow pump fails in glaucoma due to the loss of trabecular tissue elastance, as well as alterations in ciliary body tension. These processes lead to SC wall apposition and loss of motion. Visible evidence of pump failure includes a lack of pulsatile aqueous discharge into aqueous veins and reduced ability to reflux blood into SC. These alterations in the functional properties are challenging to monitor clinically. Phase-sensitive OCT now permits noninvasive, quantitative measurement of pulse-dependent TM motion in humans. This proposed conceptual model and related techniques offer a novel framework for understanding mechanisms, improving management, and development of therapeutic options for glaucoma.

- by MURRAY JOHNSTONE
- •
- Chemistry, Biomechanics, Nitric oxide (Vascular biology), Medicine

- by MURRAY JOHNSTONE
- •
- Biomechanics, Nitric oxide, Glaucoma, Shear Stress

Purpose: To describe an adjustable suture (AS) experimental model that allows for tightening, loosening and retightening of the suture tension in trabeculectomy. Methods: Standard trabeculectomy was performed in fifteen pig eyeballs. All pig eyes were tested twice: one test with conventional suture in both flap's corners (conventional suture group) and another test with a conventional suture at one corner and an adjustable suture in the other corner (AS group). The order in which each test was performed was defined by randomization. Intraocular pressure was measured at three time points: T1) when the knots were tightened; T2) when the AS was loosened or the conventional knot was removed; and T3) when the AS was retightened in the AS group or five minutes after the knot removal in the conventional suture group. Results: The mean Intraocular pressure was similar between the two groups at time point 1 (p=0.97). However, significant Intraocular pressure differences were found between eyes in the conventional and adjustable suture groups at time points 2 (12.6 ± 4.2 vs 16.3 ± 2.3 cmH 2 O, respectively, p=0.006) and 3 (12.2 ± 4.0 vs 26.4 ± 1.7cmH 2 O, respectively; p=0.001). While the conventional technique allowed only Intraocular pressure reduction (following the knot removal; T2 and T3), the AS technique allowed both Intraocular pressure reduction (T2) and elevation (T3) through the management (loosening and retightening) of the suture. Conclusion: This experimental model provides an effective noninvasive postoperative mechanism of suture tension adjustment.

- by Dr Tiago Prata
- •
- Ophthalmology, Surgery, Glaucoma, Intraocular Pressure

Choroidal effusion is an abnormal collection of fluid within the suprachoroidal potential space. It is a common complication following glaucoma filtering surgeries such as trabeculectomy. It is a clinical diagnosis that sometimes goes undetected or unreported, except when symptomatic. Reported incident rates is 7.9 – 18.8% for serous effusions and 0.7 – 3% for haemorrhagic effusions. This report aims to highlight a case of choroidal effusion after trabeculectomy and its management challenges.
Case Report
A seven year old boy presented to our facility with history of cloudy appearance of the right eye of five years duration. He was diagnosed with right infantile glaucoma. Intraocular pressures (IOP) were 44mmHg and 18mmHg right and left eyes respectively. Patient subsequently had right trabeculectomy. He developed hypotony at post-operative day two and a right choroidal effusion was noticed at post-operative day four. As a result of this, he initially had a right anterior chamber reformation with ocular viscoelastic on day seven. Later, a compression suture over the bleb and sclerostomy was performed 11 days post initial surgery. Choroidal effusion progressively regressed post-operatively and completely resolved at day five post-sclerostomy and effusion drainage.
Conclusion
Choroidal effusion is a common complication after trabeculectomy in which conservative management results in resolution. However, when conservative management fails, surgical intervention should not be delayed to maximize good outcome.

- by tarela Sarimiye and +1
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- Glaucoma Surgery, Trabeculectomy, choroidal effusion

Primary angle closure glaucoma (PACG) is a major cause of blindness worldwide. We conducted a genome-wide association study (GWAS) followed by replication in a combined total of 10,503 PACG cases and 29,567 controls drawn from 24 countries across Asia, Australia, Europe, North America, and South America. We observed significant evidence of disease association at five new genetic loci upon meta-analysis of all patient collections. These loci are at EPDR1 rs3816415 (odds ratio (OR) = 1.24, P = 5.94 × 10(-15)), CHAT rs1258267 (OR = 1.22, P = 2.85 × 10(-16)), GLIS3 rs736893 (OR = 1.18, P = 1.43 × 10(-14)), FERMT2 rs7494379 (OR = 1.14, P = 3.43 × 10(-11)), and DPM2-FAM102A rs3739821 (OR = 1.15, P = 8.32 × 10(-12)). We also confirmed significant association at three previously described loci (P…

- by Curt Hartleben-Matkin
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- Genetics, Bipolar Disorder, Biological Sciences, Glioma

Keywords: glaucoma glaucoma surgery corneal transplant penetrating keratoplasty lamellar keratoplasty endothelial keratoplasty corneal graft graft survival a b s t r a c t Glaucoma is a common cause of vision loss after corneal transplantion and is considered a major risk factor for graft failure. Glaucoma may be present before corneal transplant surgery, or increased intraocular pressure may develop after keratoplasty in up to onethird of patients. Pre-existing glaucoma should be controlled before keratoplasty, either medically or surgically. For postkeratoplasty increase in intraocular pressure; identifying the risk factors allows appropiate follow-up and management. Patients undergoing anterior lamellar keratoplasty may take advantage of reduced rates of postkeratoplasty glaucoma. Glaucoma also complicates eyes with endothelial keratoplasties, mostly related to management of intraocular pressure spikes derived from anterior chamber air bubbles.

- by Francesco D'Oria
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- Ophthalmology, Cornea, Glaucoma, Glaucoma Surgery

Purpose: To review the results of the Moorfields Safer Surgery System (MSSS) for trabeculectomy, recently introduced in Malta. Methods: Patient files were reviewed from data collected over an 18 month period, from Mater Dei Hospital. Files of all patients undergoing primary trabeculectomy with a minimum of 12 months follow up data available were reviewed. Primary outcome measure of success was defined as a 30% drop in final post-operative intraocular pressure (IOP) at 1 year. The secondary outcome measure of success was a final post-op IOP of less than 21mmHg. Unqualified success was defined as a satisfactory IOP without the need of anti-glaucoma medication, while qualified success was defined as a satisfactory IOP in those patients requiring anti-glaucoma medication. Results: 43 eyes (mean age = 66.2 yrs ± 11.7) were analysed. The mean pre-operative IOP was 27.0mmHg ± 4.6. The mean post-op IOP at one year was 15.3mmHg ±2.7. Unqualified success for the primary outcome measure was achieved in 64.1% of patients while the qualified success was achieved in 82.1%. Unqualified success for the secondary outcome measure was achieved in 72.7%, while a qualified success of 94.8% was obtained. There was a 6.8% failure rate. Conclusions: The results from this first review using the Moorfields safe surgery system for Trabeculectomy surgery in the Maltese islands compares well to the current literature.

- by Matthew Fenech
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- Ophthalmology, Glaucoma, Glaucoma Surgery

Impervious encapsulation around Ahmed glaucoma valve (AGV) results in surgical failure raising intraocular pressure (IOP). Dysregulation of extracellular matrix (ECM) molecules and cellular factors might contribute to increased hydraulic resistance to aqueous drainage. Therefore, we examined these molecules in failed AGV capsular tissue. Immunostaining for ECM molecules (collagen I, collagen III, decorin, lumican, chondroitin sulfate, aggrecan and keratan sulfate) and cellular factors (αSMA and TGFβ) was performed on excised capsules from failed AGVs and control tenon's tissue. Staining intensity of ECM molecules was assessed using Image J. Cellular factors were assessed based on positive cell counts. Histopathologically two distinct layers were visible in capsules. The inner layer (proximal to the AGV) showed significant decrease in most ECM molecules compared to outer layer. Furthermore, collagen III (p = 0.004), decorin (p = 0.02), lumican (p = 0.01) and chondroitin sulfate (p = 0.02) was significantly less in inner layer compared to tenon's tissue. Outer layer labelling however was similar to control tenon's for most ECM molecules. Significantly increased cellular expression of αSMA (p = 0.02) and TGFβ (p = 0.008) was detected within capsular tissue compared to controls. Our results suggest profibrotic activity indicated by increased αSMA and TGFβ expression and decreased expression of proteoglycan (decorin and lumican) and glycosaminoglycans (chondroitin sulfate). Additionally, we observed decreased collagen III which might reflect increased myofibroblast contractility when coupled with increased TGFβ and αSMA expression. Together these events lead to tissue dys-function potentially resulting in hydraulic resistance that may affect aqueous flow through the capsular wall.

- by Hind M Alkatan and +1
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- Glaucoma Surgery, Ophthalmic Pathology

Primary open-angle glaucoma remains one of the leading causes of irreversible blindness in the world. Intraocular pressure (IOP) is the only known treatable risk factor. Treatment of glaucoma remains imperfect because our understanding of IOP regulation is incomplete. The abnormality of IOP regulation is thought to reside in the outflow side of the system. The traditional view has been that aqueous outflow is passive, regulated by modulation of the extracellular matrix of the juxtacanalicular space of the aqueous outflow system. Despite many decades of study based on the passive conceptual framework, the cause of glaucoma remains an enigma. Lack of causal clarity is not merely an academic concern, but rather has serious clinical implications for both medical and surgical glaucoma management. This chapter reviews a new conceptual framework based on recent evidence. This alternative framework or model portrays aqueous outflow regulation as under the control of dynamic pressure-dependent tissue motion that regulates fluid passage through valve-like structures in Schlemm's canal and at collector channel entrances.

- by Murray Johnstone
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- Glaucoma, Intraocular Pressure, Glaucoma Surgery, Trabecular Meshwork

- by Igor Rudan
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- Genetics, Schizophrenia, Bipolar Disorder, Prostate Cancer