Ahmed Elmassry | University of Alexandria (original) (raw)

Papers by Ahmed Elmassry

European Journal of Ophthalmology, 2022

Introduction The aim of this study was to compare the efficacy of Photo-Activated Chromophore for... more Introduction The aim of this study was to compare the efficacy of Photo-Activated Chromophore for Keratitis – Corneal Collagen Cross-linking (PACK-CXL) of three different total UVA fluence levels and topical voriconazole in treatment of fungal keratitis experimentally induced in rabbits. Methods This is an interventional experimental study including both eyes of 16 rabbits (32 eyes). Fungal keratitis was induced by intrastromal injection of Fusarium Solani into the cornea. The rabbits were then divided into four groups (8 eyes for each) from which group A received Voriconazole eye drops and considered as control group. Group B, C, D received single PACK-CXL session with total fluence levels of 7.2, 10.0 and 15.0 J/cm2 for each respectively. Daily clinical examination was recorded and all corneas were removed for microbiology and histopathology on day ten. Results The mean clinical signs score eyes treated with high fluence PACK-CXL showed evident clinical improvement from fourth to ...

2015 ASCRS ASOA Symposium and Congress, 2015

2015 ASCRS ASOA Symposium and Congress, Apr 19, 2015

$Research paper thumbnail of Evaluation of Epithelial Mapping Changes in Cornea Before and After Photorefractive Keratectomy and Femto-Smile for Myopia$

BMC Ophthalmology, 2022

Background This study aimed to evaluate toric intraocular lens to correct of pre-existing astigma... more Background This study aimed to evaluate toric intraocular lens to correct of pre-existing astigmatism at the time of phacoemulsification compared to using of spherical intraocular lens followed by wavefront guided surface ablation. Results The patients were classified into three groups: Group A with 20 eyes of 19 patients having phacoemulsification with spherical intraocular lens only as a control group, group B with 20 eyes of 14 patients had phacoemulsification with toric intraocular lens and group C with 20 eyes of 16 patients had phacoemulsification with spherical intraocular lens and wavefront guided PRK three months later. Comparison pre-operative data for all groups showed no statistically significant difference regarding UCVA, BCVA, MRSE, and refractive astigmatism (P>0.05). Post operatively, there was a statistically significant difference for UCVA, BCVA, MRSE, and refractive astigmatism for group A compared to group B (P<0.05) and group A compared to group C but ther...

Ophthalmology Research: An International Journal

Objective: To evaluate safety and efficacy of using spherical intraocular lens followed by wavefr... more Objective: To evaluate safety and efficacy of using spherical intraocular lens followed by wavefront guided surface ablation in correction of preexisting regular corneal astigmatism. Methods: This retrospective case series study included 20 eyes of 16 patients having visually significant cataracts and co-existing regular corneal astigmatism. The patients underwent phacoemulsification with spherical intraocular lens and wavefront guided PRK three months later. Results: There was a statistically significant difference for Uncorrected Visual Acuity UCVA, Best Corrected Visual Acuity BCVA, Manifest Refraction Spherical Equivalent MRSE, and refractive astigmatism postoperatively regarding all these parameters (P˂0.05). Conclusion: Astigmatism correction during or even after cataract surgery is a safe and effective method to improve visual outcomes. Longer period of follow up are required to evaluate stability of this technique and possibility of regression.

Springer International Publishing eBooks, 2022

Increasing the thickness of the cornea offers new treatment options to the patients who may be ot... more Increasing the thickness of the cornea offers new treatment options to the patients who may be otherwise unsuitable due to thin corneas. Changing the biomechanical state of corneal stroma could stabilize the cornea and decrease the natural progression of the disease process, postponing or avoiding the need for corneal transplantation.

The XENIA lenticule (Gebauer Medizintechnik GmbH) is a single-use disk-shaped corneal stromal implant, manufactured from purified porcine corneal tissue at a given profile and variable thickness. The implant is placed in a corneal pocket at a depth of 100 μm below the Bowman’s membrane in a procedure called lenticular intracorneal keratoplasty (LIKE). It is reversible, and the lenticule can be removed in case of intolerance or other complications.

The first clinical study was presented at the Annual Winter Meeting of ESCRS in 2019, and all the eyes showed stability and clear lenticules during the follow-up period of up to 6 months. Six of seven eyes showed improvement of the CDVA. The implants are a mechanical support to the cornea; therefore, although they change its thickness and its anterior curvature, they do not change the collagen stiffness of the cornea itself. Thus they are not expected to stop the progression of disease itself, and the eyes were submitted to corneal collagen cross-linking 3 months after the implantation.

Tissue augmentation with decellularized xenogenic lenticules seems to be a promising and an effective technique to avoid corneal transplantation in highly irregular corneas where the thickness is significantly reduced.

Ophthalmic Epidemiology, 2021

PURPOSE: To describe the clinical presentation, risk factors, and treatment choices documented in... more PURPOSE: To describe the clinical presentation, risk factors, and treatment choices documented in a pediatric keratoconus population treated at a tertiary referral center in Alexandria, Egypt.METHODS: A cross-sectional study of 80 patients with keratoconus aged 18 years or younger referred to the cornea clinic at the Alexandria University Main Hospital between July 2018 and October 2019 was included. Patients' history, initial presentation, best spectacle corrected visual acuity (BSCVA), clinical signs, topographic data, and treatment were recorded.RESULTS: Thirty patients were younger than 14 years and 50 were 14 years or older. Elements of the initial presentation included decreased vision in 26 patients, itching in 20 patients, both visual impairment and itching in 16 patients, accidental discovery during vision screening at school in 15 patients, and hydrops in three patients. All patients had bilateral keratoconus, except for four patients who had previously been treated by keratoplasty (n = 156 eyes). The mean logMAR BSCVA was 0.79 ± 0.63. The mean of the average keratometry (AveK), maximum keratometry (Kmax), central corneal thickness (CCT) and thinnest pachymetry reading were 51.16 ± 7.31 D, 59.18 ± 10.38 D, 458.44 ± 55.87 µ 440.08 ± 60.18 µ, respectively. 57 eyes (36%) had stage 1 disease, 43 eyes (28%) had stage 2 disease, 17 eyes (11%) had stage 3 disease and 39 eyes (25%) had stage 4 disease, respectively. No statistically significant differences in the LogMAR BSCVA, keratometry values, CCT, thinnest pachymetry reading, and the Amsler-Krumeich (AK) staging existed between the two age groups or between boys and girls. Crosslinking was indicated in 69 eyes (44%), while keratoplasty was the only viable solution for 39 eyes (25%), with three patients requiring keratoplasty in both eyes.CONCLUSION: Keratoconus in children can result in severe loss of vision. Keratoconus screening programs in elementary schools should be considered in populations with a high incidence of keratoconus for early detection and adequate intervention.

Journal Français d'Ophtalmologie, 2008

Photokératectomie thérapeutique guidée par Pentacam ® pour traitement d'une cicatrice d'abcès de ... more Photokératectomie thérapeutique guidée par Pentacam ® pour traitement d'une cicatrice d'abcès de cornée. Pentacam ®-guided Phototherapeutic keratectomy for post-abcess corneal scar.

$Research paper thumbnail of Refractive Lens Exchange$

European Ophthalmic Review, 2015

Refractive lens exchange (RLE) still has a role in young age with anisometropia, or in an eye tha... more Refractive lens exchange (RLE) still has a role in young age with anisometropia, or in an eye that is anatomically not suitable for phakic intraocular lens (IOL) implantation or in high hypermetropia. Furthermore, in the presence of water vacuoles in the crystalline lens above the age of 40, it is recommended to perform RLE rather than phakic IOL implantation. Multifocal refractive IOLs are designed with several optical zones on the IOL. Apodised diffractive multifocal IOL has gradual diffractive steps on the IOL implant that create a smooth transition between focal points. RLE is a surgery with the same risks of a cataract surgery. Complications do occur in RLE. The mean incidence of retinal detachment is 1 % while the mean incidence of cystoid macular oedema is 0.1 %. Contraindications include unstable refraction, amblyopia and the presence of certain eye pathologies as age-related macular degeneration, glaucoma, diabetic retinopathy and a high risk of retinal detachment.

Clinical Ophthalmology, 2021

Journal of refractive surgery (Thorofare, N.J. : 1995), 2018

To present a case of bilateral, asymmetric keratoconus presenting unilaterally after partial thyr... more To present a case of bilateral, asymmetric keratoconus presenting unilaterally after partial thyroidectomy with delayed presentation in the second eye after thyrotoxicosis, with disease stabilization following corneal cross-linking (CXL). Case report and literature review. A 17-year-old girl with a history of Graves' disease underwent partial thyroidectomy without thyroid hormone replacement therapy with normal baseline ophthalmic examination of corrected distance visual acuity (CDVA) of 20/20 and no manifest astigmatism in either eye. At age 29 years, keratoconus manifested in the right eye and standard protocol CXL was performed. At age 40 years, the right eye remained stable after CXL, but keratoconus manifested in the left eye and epithelium-off accelerated CXL was performed with subsequent disease stabilization. This case demonstrates the association between thyrotoxicosis and keratoconus and the bilateral nature of keratoconus, and highlights the potentially asymmetric pre...

Journal of Clinical Research and Ophthalmology, 2020

We report a case of a patient that was implanted with an intracapsular ring during phacoemulsifi ... more We report a case of a patient that was implanted with an intracapsular ring during phacoemulsifi cation cataract surgery. Namely, we report on refraction, posterior capsule transparency and IOL ACD and document photographically the appearance of the posterior capsule. It is suggested that the presence of the intracapsular ring has inhibited epithelial cell migration and prevented the formation of posterior capsule opacifi cation (PCO) in the postoperative interval of 7 months. A comparison with the fellow eye of the same patient is made.

Clinical Ophthalmology, 2016

Purpose: To assess the safety, predictability, and effectiveness of Keraring intrastromal corneal... more Purpose: To assess the safety, predictability, and effectiveness of Keraring intrastromal corneal ring segments (ICRS) insertion assisted by femtosecond laser and corneal collagen cross-linking (CXL) for keratoconus correction. Patients and methods: In this prospective, noncomparative, and interventional case series, 160 eyes of 100 adult keratoconus patients with poor best-corrected visual acuity (BCVA) (less than 0.7) and intolerance to contact lens wear were included. Patients underwent femtosecond laser-assisted placement of ICRS and CXL. All patients were examined for a complete ophthalmological test: uncorrected visual acuity (UCVA), BCVA, spherical equivalent, keratometry (K1-flat and K2-steep), pachymetry, and Scheimpflug imaging with the Pentacam at 1 week and at 1, 3, and 6 months postoperatively. Results: At 6 months, a significant difference was observed (P,0.001) in mean UCVA and BCVA from 0.92±0.677 and 0.42±0.600 logMAR preoperatively to 0.20±0.568 and 0.119±0.619 logMAR, respectively. Mean spherical equivalent refractions were significantly lower (P,0.001) at 6 months. Mean keratometry (K) also significantly reduced (P,0.001) from 50.93±5.53 D (K1-flat) and 55.37±5.76 D (K2-steep) to 47.32±4.61 and 51.08±5.38 D, respectively. In terms of pachymetry, no significant difference was observed preoperatively versus postoperatively (P=1.000). Conclusion: Keraring ICRS insertion assisted by femtosecond laser and corneal CXL provided significant improvement in visual acuity, spherical equivalent, and keratometry, which suggests that it may be effective, safe, and predictable for keratoconus correction.

Journal of Refractive Surgery, 2020

eratoconus is a corneal ectatic disorder that starts at puberty and decreases the radius of curva... more eratoconus is a corneal ectatic disorder that starts at puberty and decreases the radius of curvature of the central cornea. 1 Kennedy et al. 2 reported that the incidence rate is 1 per 50,000 among the population. Moreover, the pathophysiological processes underlying keratoconus have not been fully explained and proposed mechanisms including oxidative damage , proteolytic degradation in the corneal stroma, epithelial mechanical injury, immunological factors, and genetic factors have been suggested. 1-4 Krachmer et al. 5 reported an incidence of keratoconus in 3.5% to 8% of patients with Down syndrome. Furthermore, hormonal imbalances affect the corneal metabolism and may be associated with keratoconus. Likewise, thyroid gland ABSTRACT PURPOSE: To examine the clinical association between thyroid gland dysfunction and keratoconus. METHODS: This was a cross-sectional case-control study conducted between May 2018 and July 2019. After performing Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany) examination, flat, steep, and maximum simulated keratometric readings were recorded for each patient. Serum concentrations of free triiodothyronine, free thyroxine, and thyroidstimulating hormone were measured. Further examinations by an endocrinologist were indicated for patients with positive laboratory results to confirm thyroid gland dysfunction. RESULTS: One hundred eighty-seven patients with bilateral keratoconus and 187 sex-and age-matched healthy controls without keratoconus were analyzed. Mean age was 26.4 ± 8.2 years for the patients with keratoconus and 27.1 ± 9.4 years for the control patients, with no significant difference. The results showed that thyroid gland dysfunction prevalence was 10 of 187 patients with keratoconus (5.3%) and 2 of 187 control patients (1.1%), and the difference was statistically significant (P = .036). For the patients with keratoconus and thyroid gland dysfunction, 8 were women and 2 were men. Additionally, 6 patients (2 men and 4 women) had hyperthyrosis and 4 women had hypothyrosis. For controls, the two patients had hypothyrosis. CONCLUSIONS: This study showed that there is a possible association between keratoconus and thyroid gland dysfunction, but more studies are needed to build upon these results.