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Papers by Melda Yenerel

PURPOSE: To report the results of Descemet‐stripping automated endothelial keratoplasty (DSAEK) i... more PURPOSE: To report the results of Descemet‐stripping automated endothelial keratoplasty (DSAEK) in eyes with toxic anterior segment syndrome (TASS) after cataract surgery. SETTING: Department of Ophthalmology, Istanbul University Cerrahpaşa Medical Faculty, Istanbul, Turkey. METHODS: In this prospective study of consecutive patients who had DSAEK for corneal failure due to TASS, the main outcome measures were corneal clarity, mean spherical equivalent (SE) refraction, preoperative and postoperative visual acuities, central corneal thickness, and endothelial cell count (ECC). RESULTS: The mean follow‐up in the 10 eyes (10 patients) was 17.1 months ± 2.4 (SD). There were no graft dislocations postoperatively, and no graft required repositioning. All grafts were clear at 12 months. Two eyes had initial graft rejection that resolved with treatment. All eyes had improved postoperative corrected distance visual acuity, with 7 eyes (70%) attaining 0.5 or better. The mean SE refraction in m...

International Ophthalmology, 2021

Iris claw intraocular lenses (IOLs) were successfully used for the management of aphakia in patie... more Iris claw intraocular lenses (IOLs) were successfully used for the management of aphakia in patients that lack capsular support. The aim of this study was to compare the clinical outcome of prepupillary and retropupillary implantation of these IOLs. The files of the 26 patients that had an iris claw IOL implantation between 2010 and 2020 were retrospectively reviewed. Detailed ophthalmological examination findings including corrected distance visual acuity (CDVA), intraocular pressure, endothelial cell counts, slit lamp and dilated fundus examination findings were specifically tabulated. Intraoperative and postoperative complications were also specifically recorded. There were 18 patients in the prepupillary implantation group and eight patients in the retropupillary implantation group. Age and gender distribution were similar between the groups. CDVA significantly increased in prepupillary and retropupillary implantation groups (p = 0.001 and p = 0.012, respectively). Median endothelial cell loss was 6.7% in prepupillary group and 7.2% in retropupillary group. The only intraoperative complication was iridodialysis (n = 1). Postoperative complications included retinal detachment (n = 1), cystoid macular edema (n = 2) and IOL tilt (n = 1). All of these complications occurred in the prepupillary implantation group. Prepupillary and retropupillary implantation of iris claw IOLs resulted with similar visual gain and endothelial loss rates in a follow-up time of 6 months. There was an insignificant trend toward a reduced complication rate following retropupillary implantation.

Turkiye Klinikleri Journal of Ophthalmology, 2016

Journal of Pediatric Ophthalmology & Strabismus, 2015

To compare the macular thickness and volume of highly myopic children with healthy controls, usin... more To compare the macular thickness and volume of highly myopic children with healthy controls, using third generation optical coherence tomography (OCT). Methods: OCT was performed on highly myopic (cycloplegic spherical equivalent refraction >-6.00 diopters [D]) children aged 3 to 7 years old and healthy controls (spherical equivalent refraction-2.00 to +4.00 D) between 2011 and 2013. OCT measurements of the average thicknesses of the fovea (central 1 mm) and inner (1 to 3 mm) and outer (3 to 6 mm) parafovea in superior, temporal, inferior, and nasal quadrants and total volume of the macular scan area were recorded. The differences between the two groups were tested with the Mann-Whitney U test. Results: There were 15 patients with high myopia and 11 controls. Foveal thickness (central 1 mm) was significantly greater in the high myopia group. The parafoveal thicknesses in all quadrants of the inner and outer circles were significantly thinner in the high myopia group. The average macular volume of the highly myopic eyes was significantly smaller than the control eyes. Conclusions: Anatomic changes in the retina occur even in young children with high myopia. Macular thickness characteristics of highly myopic children may influence the interpretation of data obtained with OCT.

Türk Oftalmoloji Dergisi, 2015

Kronik blefaritli hastalarda gözyaşı osmolaritesini araştırmak. Ge reç ve Yön tem: Çalışmaya semp... more Kronik blefaritli hastalarda gözyaşı osmolaritesini araştırmak. Ge reç ve Yön tem: Çalışmaya semptomatik kronik blefaritli olgular dahil edildi. Oftalmolojik muayeneyi takiben gözyaşı osmolaritesi ölçüldü. Ayrıca gözyaşı kırılma zamanı (GKZ), anestezili Schirmer II testi ve biyomikroskopide kornea floresein boyanması değerlendirildi. Gözyaşı osmolarite ölçümleri kontrol grubu ile karşılaştırıldı.

Molecular vision, Jan 10, 2006

To assess the cytotoxic T lymphocyte antigen 4 (CTLA4) pathway in the recoverin peptide (R64; AYA... more To assess the cytotoxic T lymphocyte antigen 4 (CTLA4) pathway in the recoverin peptide (R64; AYAQHVFRSF) mouse model of cancer-associated retinopathy (CAR) and to assess the protective effects of subconjunctival triamcinalone injections in this model. To study the role of the CTLA4 pathway on the R64-induced mouse model of CAR, BALB/c mice were immunized with R64. The mice were further intraperitoneally treated with anti-CTLA4 antibody to get stronger immunoreaction. The development of CAR was evaluated by electroretinogram (ERG) examinations 21 days after treatment. A cytotoxicity assay was employed to detect induction of R64-specific cytotoxic T lymphocytes (CTLs). Immunoblotting to assess the development of anti-recoverin antibody and a T cell proliferation assay to determine the activity of lymphocytes against R64 were examined in two experimental groups, anti-CTLA4 antibody treated and untreated mice.To study the protective effect of subconjunctival triamcinalone in this model...

Retinal Cases & Brief Reports, 2013

A 68-year-old female patient presented with decreased vision in left eye for one month duration. ... more A 68-year-old female patient presented with decreased vision in left eye for one month duration. Ophthalmic evaluation revealed a visual acuity of 20/200 with a stage 2 macular hole. The patient underwent vitrectomy with removal of posterior hyaloid with the assistance of triamcinolone. Since the macular hole was stage 2 and posterior hyaloid was observed to be firmly attached over the macular area, no attempt was made for peeling of ILM. Eye was filled with 12% C3F8. Postoperatively, the patients were instructed to keep a face-down posture for one week. At one-month visit, the patient did not report any visual improvement, and ophthalmoscopy revealed a tiny gas bubble filling the macular hole that failed to close. There was %20 gas fill. At the 7-week follow-up visit, all gas in the eye including the small gas bubble within the macular hole had resolved, and the hole remained open. The patient underwent a repeat vitrectomy in which ILM was peeled using ICG dye, and the eye was filled with 20% SF6. At 2-week follow-up visit, the hole was observed to be closed. Visual acuity improved to 20/50 at one-month visit. The reason for the macular hole nonclosure in this case may be the lack of ILM peeling in the first operation. However, we believe that microbubble localized within the hole might have contributed to the failure. It is not possible to comment on whether the tiny gas bubble caused the non-closure or the bubble just filled the hole that failed to close.

Ophthalmologica, 2010

To evaluate the correlation of microperimetry (MP) and optical coherence tomography (OCT) in eyes... more To evaluate the correlation of microperimetry (MP) and optical coherence tomography (OCT) in eyes having acute onset of central serous chorioretinopathy (CSCR). After a detailed ophthalmological examination, all cases were evaluated by fundus fluorescein angiography, OCT and MP. Mean macular thickness was detected by OCT. Mean macular sensitivity (MS) and mean defect (MD) were determined by MP. The correlation between OCT and MP findings was analyzed by Spearman's correlation test. Fifteen eyes with CSCR of 15 patients with a mean age of 40.5 +/- 6.7 years were recruited. The mean visual acuity was 0.7 +/- 0.2, and the mean macular thickness was 348.9 +/- 75.8 mum. Mean MS and MD were 13.9 +/- 4.6 and -5.2 +/- 4.1 dB, respectively. The mean macular thickness was significantly correlated with both mean MS and MD (p = 0.011 and p = 0.017, respectively). A significant correlation was also found between mean macular thickness, MS and MD in the central 1 mm, superior 3 mm and nasal 3 mm of the macula (p < 0.05). Our results demonstrated a significant correlation between structural and functional changes in CSCR. MP provides quantitative measurements of central macular function in CSCR that may supplement OCT findings as well as the better understanding of visual functions during the acute stage of the disease.

Ophthalmic Surgery, Lasers and Imaging Retina, 2011

This study examined the repeatability of and agreements between central corneal thickness measure... more This study examined the repeatability of and agreements between central corneal thickness measurements obtained by four different non-contact pachymetry devices. Seventy-eight eyes of 39 subjects were included. Central corneal thickness of each eye was measured by Visante optical coherence tomography (OCT) (Carl Zeiss Meditec Inc., Dublin, CA), Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany), Orbscan IIz topography (Bausch & Lomb Surgical Inc., San Dimas, CA), and slit-lamp OCT (SL-OCT) (Heidelberg Engineering GmbH, Heidelberg, Germany). Inter-device agreements and correlations and repeatability of each device were examined. All measurement methods correlated well with each other with a correlation coefficient greater than 0.90 and P value of less than .001 for all comparisons. However, Pentacam overestimated central corneal thickness: 546.7 ± 38.2, 535.5 ± 42.7, 531.7 ± 37.6, and 531.2 ± 36.0 μm for Pentacam, Orbscan IIz, Visante OCT, and SL-OCT, respectively (P < .001 for all comparisons versus Pentacam). Despite good correlation, magnitude of differences was high and this bias was proportional (ie, not constant across a range of corneal thickness values) for the following pairs: Orbscan versus Visante OCT, Orbscan versus SL-OCT, and Orbscan versus Pentacam (P < .001 for all comparisons). Although measurements obtained by various non-contact methods correlate well, numerical agreement of the results may not be sufficient for their interchangeable use in clinical practice.

Ophthalmic Surgery, Lasers and Imaging Retina, 2009

To demonstrate the practical and functional evaluation of flaps created intraoperatively by femto... more To demonstrate the practical and functional evaluation of flaps created intraoperatively by femtosecond laser using anterior segment optical coherence tomography (AS-OCT). The study prospectively examined 11 eyes of 6 patients who underwent uneventful LASIK surgery with the aid of the IntraLase femtosecond laser (IntraLase Corp., Irvine, CA). During the waiting period between femtosecond laser and excimer laser, all eyes were evaluated by AS-OCT to image each flap immediately before flap lifting and laser ablation. Flap thickness and residual stromal bed thickness were calculated automatically using the software's flap tool. A uniform flap was created by femtosecond laser not only in the central cornea, but also in all quadrants. The qualitative and quantitative evaluation of the corneal flap created by a femtosecond laser using AS-OCT before lifting the flap confirms that the femtosecond laser is a practical intraoperative approach that offers a safer surgery.

Ophthalmic Surgery, Lasers and Imaging Retina, 2012

Ophthalmic Surgery, Lasers and Imaging Retina, 2012

To evaluate femtosecond laser-created tunnels intraoperatively by anterior segment optical cohere... more To evaluate femtosecond laser-created tunnels intraoperatively by anterior segment optical coherence tomography (AS-OCT) during intrastromal corneal ring segment implantation. The study prospectively examined 13 eyes of 11 patients who underwent intrastromal corneal ring segment surgery with the aid of femtosecond laser. All eyes had keratoconus as the primary diagnosis. Eyes were examined by AS-OCT to image the tunnel immediately after femtosecond laser and before ring segment implantation. Tunnel depth was calculated automatically using the software's flap tool and calipers. The presence of air bubbles demonstrated the tunnel successfully by AS-OCT. Tunnel depth was measured at eight locations in four cross-sections of high-resolution cornea images. An overall evaluation was also made by changing the scan direction 360°. After confirmation that a uniform tunnel was satisfactorily created at the aimed depth, surgery proceeded with segment implantation. AS-OCT can be used intraoperatively to assess femtosecond laser-created tunnel in intrastromal corneal ring segment implantation. The qualitative and quantitative evaluation of the intrastromal tunnel by AS-OCT before implantation of the ring segments is a practical intraoperative approach that may offer a safer surgery.

Ocular Immunology and Inflammation, 2008

To report a case of unilateral late-presenting acute posterior multifocal placoid pigment epithel... more To report a case of unilateral late-presenting acute posterior multifocal placoid pigment epitheliopathy (APMPPE) with CME evaluated before and after administration of IVTA. A 29-year-old male diagnosed as APMPPE with CME was treated with IVTA. Fundus examination revealed CME and sequelae APMPPE lesions without involvement of posterior pole. FA and OCT findings were consistent with CME. After IVTA (4 mg/0.1 mL) administration; BCVA increased from 20/28 to 20/20, mean retinal thickness decreased in OCT, and mean sensitivity in microperimetry increased from 15.7 to 17.2 dB. In this case report, IVTA improved macular anatomy, visual acuity, and macular sensitivity.

Journal of Ocular Pharmacology and Therapeutics, 2008

The aim of this study was to describe a case of sterile endophthalmitis after repeated intravitre... more The aim of this study was to describe a case of sterile endophthalmitis after repeated intravitreal bevacizumab injections for the treatment of choroidal neovascularization secondary to angioid streaks. Methods: This study was done as a case report. Results: A 57-year-old man who received a third injection of intravitreal bevacizumab for the treatment of choroidal neovascularization owing to angioid streaks developed sterile endophthalmitis. The patient's condition improved after hourly topical steroid and antibiotic drops without a sequele. Conclusions: The intravitreal injection of bevacizumab has the potential for the development of sterile endophthalmitis. The patients should be warned against this possible adverse reaction, especially after repeated injections.

Japanese Journal of Ophthalmology, 2011

Purpose To assess the influence of intrastromal corneal ring segment (ICRS) implantation on corne... more Purpose To assess the influence of intrastromal corneal ring segment (ICRS) implantation on corneal biomechanics in patients with keratoconus. Methods Patients with keratoconus who underwent femtosecond laser-assisted ICRS (Keraring) implantation were evaluated with the ocular response analyzer (ORA). Metrics of corneal biomechanical parameters, including corneal hysteresis (CH) and corneal resistance factor (CRF) were measured both before and after surgery. The postoperative measurements recorded at the 1st, 3rd and 6th months, and 1st and 2nd years after surgery were analyzed. Results The mean CRF was significantly lower in the early postoperative period (1st and 3rd month); however, the difference between the mean preoperative and late postoperative (6th months, 1st and 2nd years) CRF values was not significant. There were no significant differences between the mean preoperative and postoperative CH values. Conclusions In the early postoperative period a significant temporary decrease in CRF was observed after the femtosecond laser-assisted ICRS implantation; however, this surgery did not alter the CH significantly in the same time interval. Both CH and CRF did not show significant alteration from preoperative values in the late postoperative period.

Cornea, 2010

To examine the biomechanical properties of keratoconic eyes following penetrating keratoplasty an... more To examine the biomechanical properties of keratoconic eyes following penetrating keratoplasty and to compare results with the biomechanical characteristics of manifest keratoconus, forme fruste keratoconus and normal eyes as measured with the Reichert ocular response analyzer (ORA). Methods: This retrospective analysis comprised a total of 169 eyes: 34 eyes with forme fruste keratoconus (group FF), 36 eyes with manifest keratoconus (Group KC), 36 eyes that have undergone penetrating keratoplasty (Group PK) and a control group of 63 normal eyes (Group N). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure, and Goldmann correlated intraocular pressure were measured by ORA. Central corneal thickness was calculated by the integrated handheld ultrasonic pachymeter of the ORA. The statistical analysis focused on CH and CRF changes among the 4 groups. Results: When compared with normal eyes, mean CH and CRF values were found significantly lower in all groups (

Clinical and Experimental Optometry, 2011

The aim was to investigate the short-term effects of a single intravitreal bevacizumab injectio... more The aim was to investigate the short-term effects of a single intravitreal bevacizumab injection on the retinal vessel calibre in patients with neovascular age-related macular degeneration and in patients with diabetic macular oedema. Twelve patients with neovascular age-related macular degeneration and eight patients with diabetic macular oedema were included in the study. All patients received an intravitreal injection of 1.25 mg bevacizumab. Red-free fundus photographs (35°) were acquired with a fundus camera at baseline and one day, one week and one month after the intravitreal injection. Measurements of retinal vessel diameter were made of the supero-temporal retinal venule and arteriole using the software available on the IMAGEnet program. Although there appeared to be a trend towards vasoconstriction for the measurements in the diabetic macular oedema group (both for arterioles and venules at day 7) and the age-related macular degeneration group (for venules at day 1 and for arterioles at day 7), it did not reach statistical significance (p > 0.05). Optical coherence tomography revealed a significant decrease in foveal thickness measurements in both groups at the one month visit compared with baseline. The results suggest that intravitreal injection of bevacizumab might induce retinal vasoconstriction; however, low numbers of subjects might have prevented the difference from reaching statistical significance. Further studies with a larger number of subjects would reveal the effect of intravitreal anti-vascular endothelial growth factor treatment on retinal vessel diameters more clearly.

Clinical and Experimental Optometry, 2011

A prospective evaluation of the pattern of fundus autofluorescence in cases of acute versus chron... more A prospective evaluation of the pattern of fundus autofluorescence in cases of acute versus chronic central serous chorioretinopathy (CSR). A prospective, cross-sectional, single-centre investigation was performed using three diagnostic techniques, namely, fundus autofluorescence, optical coherence tomography and fundus fluorescein angiography to evaluate a sample of patients (n = 42 eyes) with both acute (n = 25 eyes) and chronic (n = 17 eyes) CSR. Hypoautofluoresecence was found in 80 per cent (20 eyes) and 88.2 per cent (15 eyes) of eyes in the acute and chronic central serous chorioretinopathy groups, respectively, corresponding to the leakage points depicted by fluorescein angiography. Hypoautofluoresence corresponding to the areas of subretinal fluid accumulation was seen in 92 per cent (23 eyes) and 82.3 per cent (14 eyes) of the acute and chronic central serous chorioretinopathy groups, respectively. In two eyes (11.6 per cent) with chronic CSR, hyperautofluorescent changes were noted at the previous leakage points. In the acute CSR group, speckled hyperautofluorescence was detected in nine eyes (36 per cent) after the resolution of subretinal fluid. In the chronic CSR group, simultaneous speckled hyperautofluorescence was detected in the previous areas of subretinal fluid accumulation in 12 eyes (70.5 per cent). Fundus autofluorescence imaging delineates endogenous fluorescence derived mainly from lipofuscin within the retinal pigment epithelium (RPE) layer and therefore permits evaluation of functional alterations in the RPE in numerous retinal diseases. Data from fundus autofluorescence revealed distinctive findings in acute and chronic CSR. Fundus autofluorescence imaging may be used as a supplementary diagnostic tool for identifying patients with CSR and differentiation may be made between acute and chronic cases.

Archives of Ophthalmology, 2005

... Dr Saperstein, De-partment of Ophthalmology, RR 801, Box 356485, University of Washington, 19... more ... Dr Saperstein, De-partment of Ophthalmology, RR 801, Box 356485, University of Washington, 1959 Pacific St NE, Seattle, WA 98195 (dsapers@u .washington.edu). ... N. Melda Yenerel, MD Robert Boada, MD Bradley Clifton Jing Zhang, MD David A. Saperstein, MD ...

Ophthalmic Surgery, Lasers and Imaging Retina, 2011

to investigate the efficacy of anterior segment optical coherence tomography (AS-OCT) for calcula... more to investigate the efficacy of anterior segment optical coherence tomography (AS-OCT) for calculating flap thickness in femtosecond laser-assisted laser in situ keratomileusis. fifty-one eyes of 26 patients with myopia and myopic astigmatism were included in this prospective study. High-resolution corneal images were evaluated at 1 week and 1 month postoperatively. Images along the horizontal meridian were measured with the flap tool at seven points. measurements at vertex and at 1 mm nasally and temporally from the vertex were indistinct but easily defined. Although statistically not significant, flaps were found to be thinner in the central cornea and thicker in the periphery (P > .05). AS-OCT provides detailed high-resolution images for quantitative evaluation of the flap-stroma relationship, but it may not be precise in the central 2-mm area of the cornea. Despite this, AS-OCT is an imaging tool with significant utility.

PURPOSE: To report the results of Descemet‐stripping automated endothelial keratoplasty (DSAEK) i... more PURPOSE: To report the results of Descemet‐stripping automated endothelial keratoplasty (DSAEK) in eyes with toxic anterior segment syndrome (TASS) after cataract surgery. SETTING: Department of Ophthalmology, Istanbul University Cerrahpaşa Medical Faculty, Istanbul, Turkey. METHODS: In this prospective study of consecutive patients who had DSAEK for corneal failure due to TASS, the main outcome measures were corneal clarity, mean spherical equivalent (SE) refraction, preoperative and postoperative visual acuities, central corneal thickness, and endothelial cell count (ECC). RESULTS: The mean follow‐up in the 10 eyes (10 patients) was 17.1 months ± 2.4 (SD). There were no graft dislocations postoperatively, and no graft required repositioning. All grafts were clear at 12 months. Two eyes had initial graft rejection that resolved with treatment. All eyes had improved postoperative corrected distance visual acuity, with 7 eyes (70%) attaining 0.5 or better. The mean SE refraction in m...

International Ophthalmology, 2021

Iris claw intraocular lenses (IOLs) were successfully used for the management of aphakia in patie... more Iris claw intraocular lenses (IOLs) were successfully used for the management of aphakia in patients that lack capsular support. The aim of this study was to compare the clinical outcome of prepupillary and retropupillary implantation of these IOLs. The files of the 26 patients that had an iris claw IOL implantation between 2010 and 2020 were retrospectively reviewed. Detailed ophthalmological examination findings including corrected distance visual acuity (CDVA), intraocular pressure, endothelial cell counts, slit lamp and dilated fundus examination findings were specifically tabulated. Intraoperative and postoperative complications were also specifically recorded. There were 18 patients in the prepupillary implantation group and eight patients in the retropupillary implantation group. Age and gender distribution were similar between the groups. CDVA significantly increased in prepupillary and retropupillary implantation groups (p = 0.001 and p = 0.012, respectively). Median endothelial cell loss was 6.7% in prepupillary group and 7.2% in retropupillary group. The only intraoperative complication was iridodialysis (n = 1). Postoperative complications included retinal detachment (n = 1), cystoid macular edema (n = 2) and IOL tilt (n = 1). All of these complications occurred in the prepupillary implantation group. Prepupillary and retropupillary implantation of iris claw IOLs resulted with similar visual gain and endothelial loss rates in a follow-up time of 6 months. There was an insignificant trend toward a reduced complication rate following retropupillary implantation.

Turkiye Klinikleri Journal of Ophthalmology, 2016

Journal of Pediatric Ophthalmology & Strabismus, 2015

To compare the macular thickness and volume of highly myopic children with healthy controls, usin... more To compare the macular thickness and volume of highly myopic children with healthy controls, using third generation optical coherence tomography (OCT). Methods: OCT was performed on highly myopic (cycloplegic spherical equivalent refraction >-6.00 diopters [D]) children aged 3 to 7 years old and healthy controls (spherical equivalent refraction-2.00 to +4.00 D) between 2011 and 2013. OCT measurements of the average thicknesses of the fovea (central 1 mm) and inner (1 to 3 mm) and outer (3 to 6 mm) parafovea in superior, temporal, inferior, and nasal quadrants and total volume of the macular scan area were recorded. The differences between the two groups were tested with the Mann-Whitney U test. Results: There were 15 patients with high myopia and 11 controls. Foveal thickness (central 1 mm) was significantly greater in the high myopia group. The parafoveal thicknesses in all quadrants of the inner and outer circles were significantly thinner in the high myopia group. The average macular volume of the highly myopic eyes was significantly smaller than the control eyes. Conclusions: Anatomic changes in the retina occur even in young children with high myopia. Macular thickness characteristics of highly myopic children may influence the interpretation of data obtained with OCT.

Türk Oftalmoloji Dergisi, 2015

Kronik blefaritli hastalarda gözyaşı osmolaritesini araştırmak. Ge reç ve Yön tem: Çalışmaya semp... more Kronik blefaritli hastalarda gözyaşı osmolaritesini araştırmak. Ge reç ve Yön tem: Çalışmaya semptomatik kronik blefaritli olgular dahil edildi. Oftalmolojik muayeneyi takiben gözyaşı osmolaritesi ölçüldü. Ayrıca gözyaşı kırılma zamanı (GKZ), anestezili Schirmer II testi ve biyomikroskopide kornea floresein boyanması değerlendirildi. Gözyaşı osmolarite ölçümleri kontrol grubu ile karşılaştırıldı.

Molecular vision, Jan 10, 2006

To assess the cytotoxic T lymphocyte antigen 4 (CTLA4) pathway in the recoverin peptide (R64; AYA... more To assess the cytotoxic T lymphocyte antigen 4 (CTLA4) pathway in the recoverin peptide (R64; AYAQHVFRSF) mouse model of cancer-associated retinopathy (CAR) and to assess the protective effects of subconjunctival triamcinalone injections in this model. To study the role of the CTLA4 pathway on the R64-induced mouse model of CAR, BALB/c mice were immunized with R64. The mice were further intraperitoneally treated with anti-CTLA4 antibody to get stronger immunoreaction. The development of CAR was evaluated by electroretinogram (ERG) examinations 21 days after treatment. A cytotoxicity assay was employed to detect induction of R64-specific cytotoxic T lymphocytes (CTLs). Immunoblotting to assess the development of anti-recoverin antibody and a T cell proliferation assay to determine the activity of lymphocytes against R64 were examined in two experimental groups, anti-CTLA4 antibody treated and untreated mice.To study the protective effect of subconjunctival triamcinalone in this model...

Retinal Cases & Brief Reports, 2013

A 68-year-old female patient presented with decreased vision in left eye for one month duration. ... more A 68-year-old female patient presented with decreased vision in left eye for one month duration. Ophthalmic evaluation revealed a visual acuity of 20/200 with a stage 2 macular hole. The patient underwent vitrectomy with removal of posterior hyaloid with the assistance of triamcinolone. Since the macular hole was stage 2 and posterior hyaloid was observed to be firmly attached over the macular area, no attempt was made for peeling of ILM. Eye was filled with 12% C3F8. Postoperatively, the patients were instructed to keep a face-down posture for one week. At one-month visit, the patient did not report any visual improvement, and ophthalmoscopy revealed a tiny gas bubble filling the macular hole that failed to close. There was %20 gas fill. At the 7-week follow-up visit, all gas in the eye including the small gas bubble within the macular hole had resolved, and the hole remained open. The patient underwent a repeat vitrectomy in which ILM was peeled using ICG dye, and the eye was filled with 20% SF6. At 2-week follow-up visit, the hole was observed to be closed. Visual acuity improved to 20/50 at one-month visit. The reason for the macular hole nonclosure in this case may be the lack of ILM peeling in the first operation. However, we believe that microbubble localized within the hole might have contributed to the failure. It is not possible to comment on whether the tiny gas bubble caused the non-closure or the bubble just filled the hole that failed to close.

Ophthalmologica, 2010

To evaluate the correlation of microperimetry (MP) and optical coherence tomography (OCT) in eyes... more To evaluate the correlation of microperimetry (MP) and optical coherence tomography (OCT) in eyes having acute onset of central serous chorioretinopathy (CSCR). After a detailed ophthalmological examination, all cases were evaluated by fundus fluorescein angiography, OCT and MP. Mean macular thickness was detected by OCT. Mean macular sensitivity (MS) and mean defect (MD) were determined by MP. The correlation between OCT and MP findings was analyzed by Spearman's correlation test. Fifteen eyes with CSCR of 15 patients with a mean age of 40.5 +/- 6.7 years were recruited. The mean visual acuity was 0.7 +/- 0.2, and the mean macular thickness was 348.9 +/- 75.8 mum. Mean MS and MD were 13.9 +/- 4.6 and -5.2 +/- 4.1 dB, respectively. The mean macular thickness was significantly correlated with both mean MS and MD (p = 0.011 and p = 0.017, respectively). A significant correlation was also found between mean macular thickness, MS and MD in the central 1 mm, superior 3 mm and nasal 3 mm of the macula (p < 0.05). Our results demonstrated a significant correlation between structural and functional changes in CSCR. MP provides quantitative measurements of central macular function in CSCR that may supplement OCT findings as well as the better understanding of visual functions during the acute stage of the disease.

Ophthalmic Surgery, Lasers and Imaging Retina, 2011

This study examined the repeatability of and agreements between central corneal thickness measure... more This study examined the repeatability of and agreements between central corneal thickness measurements obtained by four different non-contact pachymetry devices. Seventy-eight eyes of 39 subjects were included. Central corneal thickness of each eye was measured by Visante optical coherence tomography (OCT) (Carl Zeiss Meditec Inc., Dublin, CA), Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany), Orbscan IIz topography (Bausch & Lomb Surgical Inc., San Dimas, CA), and slit-lamp OCT (SL-OCT) (Heidelberg Engineering GmbH, Heidelberg, Germany). Inter-device agreements and correlations and repeatability of each device were examined. All measurement methods correlated well with each other with a correlation coefficient greater than 0.90 and P value of less than .001 for all comparisons. However, Pentacam overestimated central corneal thickness: 546.7 ± 38.2, 535.5 ± 42.7, 531.7 ± 37.6, and 531.2 ± 36.0 μm for Pentacam, Orbscan IIz, Visante OCT, and SL-OCT, respectively (P < .001 for all comparisons versus Pentacam). Despite good correlation, magnitude of differences was high and this bias was proportional (ie, not constant across a range of corneal thickness values) for the following pairs: Orbscan versus Visante OCT, Orbscan versus SL-OCT, and Orbscan versus Pentacam (P < .001 for all comparisons). Although measurements obtained by various non-contact methods correlate well, numerical agreement of the results may not be sufficient for their interchangeable use in clinical practice.

Ophthalmic Surgery, Lasers and Imaging Retina, 2009

To demonstrate the practical and functional evaluation of flaps created intraoperatively by femto... more To demonstrate the practical and functional evaluation of flaps created intraoperatively by femtosecond laser using anterior segment optical coherence tomography (AS-OCT). The study prospectively examined 11 eyes of 6 patients who underwent uneventful LASIK surgery with the aid of the IntraLase femtosecond laser (IntraLase Corp., Irvine, CA). During the waiting period between femtosecond laser and excimer laser, all eyes were evaluated by AS-OCT to image each flap immediately before flap lifting and laser ablation. Flap thickness and residual stromal bed thickness were calculated automatically using the software's flap tool. A uniform flap was created by femtosecond laser not only in the central cornea, but also in all quadrants. The qualitative and quantitative evaluation of the corneal flap created by a femtosecond laser using AS-OCT before lifting the flap confirms that the femtosecond laser is a practical intraoperative approach that offers a safer surgery.

Ophthalmic Surgery, Lasers and Imaging Retina, 2012

Ophthalmic Surgery, Lasers and Imaging Retina, 2012

To evaluate femtosecond laser-created tunnels intraoperatively by anterior segment optical cohere... more To evaluate femtosecond laser-created tunnels intraoperatively by anterior segment optical coherence tomography (AS-OCT) during intrastromal corneal ring segment implantation. The study prospectively examined 13 eyes of 11 patients who underwent intrastromal corneal ring segment surgery with the aid of femtosecond laser. All eyes had keratoconus as the primary diagnosis. Eyes were examined by AS-OCT to image the tunnel immediately after femtosecond laser and before ring segment implantation. Tunnel depth was calculated automatically using the software's flap tool and calipers. The presence of air bubbles demonstrated the tunnel successfully by AS-OCT. Tunnel depth was measured at eight locations in four cross-sections of high-resolution cornea images. An overall evaluation was also made by changing the scan direction 360°. After confirmation that a uniform tunnel was satisfactorily created at the aimed depth, surgery proceeded with segment implantation. AS-OCT can be used intraoperatively to assess femtosecond laser-created tunnel in intrastromal corneal ring segment implantation. The qualitative and quantitative evaluation of the intrastromal tunnel by AS-OCT before implantation of the ring segments is a practical intraoperative approach that may offer a safer surgery.

Ocular Immunology and Inflammation, 2008

To report a case of unilateral late-presenting acute posterior multifocal placoid pigment epithel... more To report a case of unilateral late-presenting acute posterior multifocal placoid pigment epitheliopathy (APMPPE) with CME evaluated before and after administration of IVTA. A 29-year-old male diagnosed as APMPPE with CME was treated with IVTA. Fundus examination revealed CME and sequelae APMPPE lesions without involvement of posterior pole. FA and OCT findings were consistent with CME. After IVTA (4 mg/0.1 mL) administration; BCVA increased from 20/28 to 20/20, mean retinal thickness decreased in OCT, and mean sensitivity in microperimetry increased from 15.7 to 17.2 dB. In this case report, IVTA improved macular anatomy, visual acuity, and macular sensitivity.

Journal of Ocular Pharmacology and Therapeutics, 2008

The aim of this study was to describe a case of sterile endophthalmitis after repeated intravitre... more The aim of this study was to describe a case of sterile endophthalmitis after repeated intravitreal bevacizumab injections for the treatment of choroidal neovascularization secondary to angioid streaks. Methods: This study was done as a case report. Results: A 57-year-old man who received a third injection of intravitreal bevacizumab for the treatment of choroidal neovascularization owing to angioid streaks developed sterile endophthalmitis. The patient's condition improved after hourly topical steroid and antibiotic drops without a sequele. Conclusions: The intravitreal injection of bevacizumab has the potential for the development of sterile endophthalmitis. The patients should be warned against this possible adverse reaction, especially after repeated injections.

Japanese Journal of Ophthalmology, 2011

Purpose To assess the influence of intrastromal corneal ring segment (ICRS) implantation on corne... more Purpose To assess the influence of intrastromal corneal ring segment (ICRS) implantation on corneal biomechanics in patients with keratoconus. Methods Patients with keratoconus who underwent femtosecond laser-assisted ICRS (Keraring) implantation were evaluated with the ocular response analyzer (ORA). Metrics of corneal biomechanical parameters, including corneal hysteresis (CH) and corneal resistance factor (CRF) were measured both before and after surgery. The postoperative measurements recorded at the 1st, 3rd and 6th months, and 1st and 2nd years after surgery were analyzed. Results The mean CRF was significantly lower in the early postoperative period (1st and 3rd month); however, the difference between the mean preoperative and late postoperative (6th months, 1st and 2nd years) CRF values was not significant. There were no significant differences between the mean preoperative and postoperative CH values. Conclusions In the early postoperative period a significant temporary decrease in CRF was observed after the femtosecond laser-assisted ICRS implantation; however, this surgery did not alter the CH significantly in the same time interval. Both CH and CRF did not show significant alteration from preoperative values in the late postoperative period.

Cornea, 2010

To examine the biomechanical properties of keratoconic eyes following penetrating keratoplasty an... more To examine the biomechanical properties of keratoconic eyes following penetrating keratoplasty and to compare results with the biomechanical characteristics of manifest keratoconus, forme fruste keratoconus and normal eyes as measured with the Reichert ocular response analyzer (ORA). Methods: This retrospective analysis comprised a total of 169 eyes: 34 eyes with forme fruste keratoconus (group FF), 36 eyes with manifest keratoconus (Group KC), 36 eyes that have undergone penetrating keratoplasty (Group PK) and a control group of 63 normal eyes (Group N). Corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure, and Goldmann correlated intraocular pressure were measured by ORA. Central corneal thickness was calculated by the integrated handheld ultrasonic pachymeter of the ORA. The statistical analysis focused on CH and CRF changes among the 4 groups. Results: When compared with normal eyes, mean CH and CRF values were found significantly lower in all groups (

Clinical and Experimental Optometry, 2011

The aim was to investigate the short-term effects of a single intravitreal bevacizumab injectio... more The aim was to investigate the short-term effects of a single intravitreal bevacizumab injection on the retinal vessel calibre in patients with neovascular age-related macular degeneration and in patients with diabetic macular oedema. Twelve patients with neovascular age-related macular degeneration and eight patients with diabetic macular oedema were included in the study. All patients received an intravitreal injection of 1.25 mg bevacizumab. Red-free fundus photographs (35°) were acquired with a fundus camera at baseline and one day, one week and one month after the intravitreal injection. Measurements of retinal vessel diameter were made of the supero-temporal retinal venule and arteriole using the software available on the IMAGEnet program. Although there appeared to be a trend towards vasoconstriction for the measurements in the diabetic macular oedema group (both for arterioles and venules at day 7) and the age-related macular degeneration group (for venules at day 1 and for arterioles at day 7), it did not reach statistical significance (p > 0.05). Optical coherence tomography revealed a significant decrease in foveal thickness measurements in both groups at the one month visit compared with baseline. The results suggest that intravitreal injection of bevacizumab might induce retinal vasoconstriction; however, low numbers of subjects might have prevented the difference from reaching statistical significance. Further studies with a larger number of subjects would reveal the effect of intravitreal anti-vascular endothelial growth factor treatment on retinal vessel diameters more clearly.

Clinical and Experimental Optometry, 2011

A prospective evaluation of the pattern of fundus autofluorescence in cases of acute versus chron... more A prospective evaluation of the pattern of fundus autofluorescence in cases of acute versus chronic central serous chorioretinopathy (CSR). A prospective, cross-sectional, single-centre investigation was performed using three diagnostic techniques, namely, fundus autofluorescence, optical coherence tomography and fundus fluorescein angiography to evaluate a sample of patients (n = 42 eyes) with both acute (n = 25 eyes) and chronic (n = 17 eyes) CSR. Hypoautofluoresecence was found in 80 per cent (20 eyes) and 88.2 per cent (15 eyes) of eyes in the acute and chronic central serous chorioretinopathy groups, respectively, corresponding to the leakage points depicted by fluorescein angiography. Hypoautofluoresence corresponding to the areas of subretinal fluid accumulation was seen in 92 per cent (23 eyes) and 82.3 per cent (14 eyes) of the acute and chronic central serous chorioretinopathy groups, respectively. In two eyes (11.6 per cent) with chronic CSR, hyperautofluorescent changes were noted at the previous leakage points. In the acute CSR group, speckled hyperautofluorescence was detected in nine eyes (36 per cent) after the resolution of subretinal fluid. In the chronic CSR group, simultaneous speckled hyperautofluorescence was detected in the previous areas of subretinal fluid accumulation in 12 eyes (70.5 per cent). Fundus autofluorescence imaging delineates endogenous fluorescence derived mainly from lipofuscin within the retinal pigment epithelium (RPE) layer and therefore permits evaluation of functional alterations in the RPE in numerous retinal diseases. Data from fundus autofluorescence revealed distinctive findings in acute and chronic CSR. Fundus autofluorescence imaging may be used as a supplementary diagnostic tool for identifying patients with CSR and differentiation may be made between acute and chronic cases.

Archives of Ophthalmology, 2005

... Dr Saperstein, De-partment of Ophthalmology, RR 801, Box 356485, University of Washington, 19... more ... Dr Saperstein, De-partment of Ophthalmology, RR 801, Box 356485, University of Washington, 1959 Pacific St NE, Seattle, WA 98195 (dsapers@u .washington.edu). ... N. Melda Yenerel, MD Robert Boada, MD Bradley Clifton Jing Zhang, MD David A. Saperstein, MD ...

Ophthalmic Surgery, Lasers and Imaging Retina, 2011

to investigate the efficacy of anterior segment optical coherence tomography (AS-OCT) for calcula... more to investigate the efficacy of anterior segment optical coherence tomography (AS-OCT) for calculating flap thickness in femtosecond laser-assisted laser in situ keratomileusis. fifty-one eyes of 26 patients with myopia and myopic astigmatism were included in this prospective study. High-resolution corneal images were evaluated at 1 week and 1 month postoperatively. Images along the horizontal meridian were measured with the flap tool at seven points. measurements at vertex and at 1 mm nasally and temporally from the vertex were indistinct but easily defined. Although statistically not significant, flaps were found to be thinner in the central cornea and thicker in the periphery (P > .05). AS-OCT provides detailed high-resolution images for quantitative evaluation of the flap-stroma relationship, but it may not be precise in the central 2-mm area of the cornea. Despite this, AS-OCT is an imaging tool with significant utility.