Association of the CYP39A1 G204E Genetic Variant with Increased Risk of Glaucoma and Blindness in Patients with Exfoliation Syndrome.

PURPOSE: Carriers of functionally deficient mutations in the CYP39A1 gene have been recently reported to have a 2-fold increased risk of exfoliation syndrome (XFS). The aim of this study was to evaluate the risk of blindness and related clinical phenotypes of XFS patients carrying the loss-of-function CYP39A1 G204E mutation in comparison with XFS patients without any CYP39A1 mutation. DESIGN: Retrospective case study. PARTICIPANTS: A total of 35 patients diagnosed with XFS carrying the CYP39A1 G204E mutation and 150 XFS patients without any CYP39A1 mutation who were randomly selected from the Japanese XFS cohort. METHODS: Two-sided Fisher exact test with an alpha level < 0.05 was used to estimate the significance of the calculated odds ratio (OR) for all categorical measures. Comparisons between groups of subjects were performed using linear mixed effect models with group as random effect and taking possible dependence between eyes within a subject into account. MAIN OUTCOME MEASURES: Primary analysis compared the incidence of blindness (defined as visual acuity [VA] < 0.05 decimal), prevalence of exfoliation glaucoma (XFG), history of glaucoma surgery, and indices of glaucoma severity such as visual field (VF) mean deviation (MD), intraocular pressure (IOP), and vertical cup-disc ratio (CDR) between CYP39A1 G204E carriers and those without any CYP39A1 mutation. RESULTS: The overall risk for blindness was significantly higher in XFS patients carrying the CYP39A1 G204E variant (10/35 [28.6%]) compared with XFS patients without any CYP39A1 mutations (8/150 [5.4%]; odds ratio [OR], 7.1; 95% confidence interval [CI], 2.7-20.2]; P < 0.001). A higher proportion of XFS patients with the CYP39A1 G204E mutation (23/35 [65.7%]) had evidence of XFG in at least 1 eye compared with the comparison group (41/150 [27.3%]; OR, 5.1; 95% CI, 2.4-11.4]; P < 0.0001). Significantly higher peak IOP, larger vertical CDR, and worse VF MD were also found in CYP39A1 G204E variant carriers (P < 0.001). Additionally, patients with the CYP39A1 G204E mutation (18/35 [51.4%]) required more laser or glaucoma surgical interventions compared with those without any CYP39A1 mutation (32/150 [21.3%], P < 0.001). CONCLUSIONS: Patients with XFS carrying the CYP39A1 G204E mutation had significantly increased risk of blindness, higher occurrence of XFG, and more severe glaucoma compared with patients with XFS without any CYP39A1 mutation.

Overestimation of corneal endothelial cell density by automated method in glaucomatous eyes with impaired corneal endothelial cells.

PURPOSE: To determine between-method differences in corneal endothelial cell parameters using center and automated methods of non-contact specular microscopy (CellCheck software of Konan, Inc.) in glaucomatous eyes. METHODS: We analyzed the central corneal endothelial cell density (ECD) of 245 glaucomatous eyes using center (ECD-Ce) and automated methods (ECD-Au). Based on the ECD-Ce, we allocated subjects to Groups 1 to 10 (at 250 cells/mm2 intervals) and evaluated the ECD, coefficient of variation in cell area (CV), and percentage of hexagonal cells (HEX). RESULTS: There was a close correlation (r = 0.91) between the ECD values measured using both methods. However, ECD-Au were significantly higher than those measured by the center method when ECD-Ce was less than 2500 (in Groups 1 to 8; P < 0.001 to P = 0.006). The regression equation of (ECD-Au-ECD-Ce) = 1028-0.397*ECD-Ce shows greater deviation in eyes with lower ECD, and this difference became 0 when ECD -Ce was 2593 cells/mm2. None of the 44 subjects with an ECD-Ce of < 1000 cells/mm2 recorded an ECD-Au < 1000 cells/mm2. Compared with the center method, the automated method had higher and lower median CV and HEX values, respectively (P < 0.001). The between-method differences in both CV and HEX were negatively correlated with ECD-Ce (r = -0.49, P < 0.001 and r = -0.25, P < 0.001, respectively). CONCLUSION: The automated method of the CellCheck software overestimates ECD in eyes with lower ECD values and may overlook risk of corneal decompensation.

MÜLLER CELL CONE-ASSOCIATED FOVEAL DETACHMENT AS A RISK FACTOR FOR VISUAL ACUITY LOSS AFTER GLAUCOMA FILTERING SURGERY.

PURPOSE: To examine hypotony-associated foveal lesions (FovLs) using optical coherence tomography, and to assess the risk factors of visual deterioration after glaucoma filtering surgery. METHODS: Parameters that may be associated with postsurgical deterioration of visual acuity were retrospectively studied in 44 eyes of 44 patients who experienced postsurgical intraocular hypotension ≤6 mmHg between 2015 and 2019. RESULTS: Six eyes (14%) had FovLs, such as detachment of photoreceptors (5 eyes, 11%) and acquired vitelliform lesions (1 eye, 2%) at 3 months after trabeculectomy. Logistic regression analysis revealed that hypotony maculopathy (P = 0.0141 at 3 months) and FovLs (P = 0.0486 and 0.0296 at 3 and 12 months, respectively) were significant risk factors for Visual acuity loss after trabeculectomy. The FovLs were located just behind the Müller cell cone. Visual acuity at 3 and 12 months after surgery in patients with FovLs was significantly lower than in those without FovLs (P = 0.0013 and P = 0.006, respectively). Epiretinal membrane was more common in eyes with FovLs (5 of 6 eyes, 83%) than in eyes without FovLs (7 of 38 eyes, 18%; P = 0.0037). CONCLUSION: Müller cell cone-associated FovLs lead to long-lasting visual acuity loss after filtering surgery.

Corynebacterium ocular infection after Baerveldt glaucoma implant surgery: treatment involving immediate tube withdrawal and temporary subconjunctival tube placement: a case report.

BACKGROUND: We report a case of Corynebacterium endophthalmitis secondary to tube exposure following Baerveldt glaucoma implant surgery that was successfully treated with prompt tube withdrawal and temporary subconjunctival tube placement without removing the glaucoma drainage device. CASE PRESENTATION: A 65-year-old Japanese man with secondary glaucoma underwent glaucoma drainage device surgery with a donor scleral patch graft in the inferonasal quadrant of his right eye. Ten months after surgery, he presented with tube exposure due to dehiscence of the overlying conjunctiva and erosion of the scleral patch graft. Eleven days later, mild inflammation was found in the anterior chamber and anterior vitreous body, with the root of the tube surrounded by a plaque at the site of insertion in the anterior chamber. He was diagnosed with infectious endophthalmitis secondary to tube exposure. Two days later, since medical therapy was ineffective, the tube was withdrawn from the anterior chamber and irrigated with a polyvinyl alcohol-iodine solution, and the tube was tucked into the subconjunctival space. Complete resolution of the infection was achieved 1.5 months later. The tube was reinserted nasally into the anterior chamber and covered with a scleral patch graft and a free limbal conjunctival autograft. Thereafter, there has been no recurrence of infection or tube exposure. Twenty eight months after tube reinsertion, his right best-corrected visual acuity was 20/50 and intraocular pressure was 12 mmHg. CONCLUSION: Prompt tube withdrawal and temporary subconjunctival tube placement followed by tube reinsertion may be effective for endophthalmitis associated with tube exposure after glaucoma drainage device surgery.

Association of Rare CYP39A1 Variants With Exfoliation Syndrome Involving the Anterior Chamber of the Eye.

Importance: Exfoliation syndrome is a systemic disorder characterized by progressive accumulation of abnormal fibrillar protein aggregates manifesting clinically in the anterior chamber of the eye. This disorder is the most commonly known cause of glaucoma and a major cause of irreversible blindness. Objective: To determine if exfoliation syndrome is associated with rare, protein-changing variants predicted to impair protein function. Design, Setting, and Participants: A 2-stage, case-control, whole-exome sequencing association study with a discovery cohort and 2 independently ascertained validation cohorts. Study participants from 14 countries were enrolled between February 1999 and December 2019. The date of last clinical follow-up was December 2019. Affected individuals had exfoliation material on anterior segment structures of at least 1 eye as visualized by slit lamp examination. Unaffected individuals had no signs of exfoliation syndrome. Exposures: Rare, coding-sequence genetic variants predicted to be damaging by bioinformatic algorithms trained to recognize alterations that impair protein function. Main Outcomes and Measures: The primary outcome was the presence of exfoliation syndrome. Exome-wide significance for detected variants was defined as P < 2.5 × 10-6. The secondary outcomes included biochemical enzymatic assays and gene expression analyses. Results: The discovery cohort included 4028 participants with exfoliation syndrome (median age, 78 years [interquartile range, 73-83 years]; 2377 [59.0%] women) and 5638 participants without exfoliation syndrome (median age, 72 years [interquartile range, 65-78 years]; 3159 [56.0%] women). In the discovery cohort, persons with exfoliation syndrome, compared with those without exfoliation syndrome, were significantly more likely to carry damaging CYP39A1 variants (1.3% vs 0.30%, respectively; odds ratio, 3.55 [95% CI, 2.07-6.10]; P = 6.1 × 10-7). This outcome was validated in 2 independent cohorts. The first validation cohort included 2337 individuals with exfoliation syndrome (median age, 74 years; 1132 women; n = 1934 with demographic data) and 2813 individuals without exfoliation syndrome (median age, 72 years; 1287 women; n = 2421 with demographic data). The second validation cohort included 1663 individuals with exfoliation syndrome (median age, 75 years; 587 women; n = 1064 with demographic data) and 3962 individuals without exfoliation syndrome (median age, 74 years; 951 women; n = 1555 with demographic data). Of the individuals from both validation cohorts, 5.2% with exfoliation syndrome carried CYP39A1 damaging alleles vs 3.1% without exfoliation syndrome (odds ratio, 1.82 [95% CI, 1.47-2.26]; P < .001). Biochemical assays classified 34 of 42 damaging CYP39A1 alleles as functionally deficient (median reduction in enzymatic activity compared with wild-type CYP39A1, 94.4% [interquartile range, 78.7%-98.2%] for the 34 deficient variants). CYP39A1 transcript expression was 47% lower (95% CI, 30%-64% lower; P < .001) in ciliary body tissues from individuals with exfoliation syndrome compared with individuals without exfoliation syndrome. Conclusions and Relevance: In this whole-exome sequencing case-control study, presence of exfoliation syndrome was significantly associated with carriage of functionally deficient CYP39A1 sequence variants. Further research is needed to understand the clinical implications of these findings.

Implication of Deep-Vascular-Layer Alteration Detected by Optical Coherence Tomography Angiography for the Pathogenesis of Diabetic Retinopathy.

The aim of this narrative mini review is to analyze optical coherence tomography angiography (OCTA) parameters from reports that involved both superficial and deep vascular layers in patients with diabetes and to assess their relevance for the pathogenesis of diabetic retinopathy (DR). Papers published from January 2015 to August 2018 describing the use of OCTA in diabetes were identified and reviewed through a Medline/PubMed search. OCTA studies suggest that parameters are altered in patients with diabetes in all retinal vascular layers. From all included studies that evaluated both the superficial and the deep vascular layer, a number of studies suggested that the deep vascular layer was affected at an earlier stage of DR. OCTA parameter alterations were more prominent in the deep vascular layer than in the superficial vascular layer in patients with DR, and deep-vascular-layer alterations were most evident in patients with diabetic macular edema. Regarding that retinal venules originate from the deep vascular layer of the retina, alteration of OCTA parameters at the deep vascular layer in diabetic patients may imply a predominant affection of the venous side of the retinal vascular system in the pathogenesis of DR.

Increase in the OCT angiographic peripapillary vessel density by ROCK inhibitor ripasudil instillation: a comparison with brimonidine.

PURPOSE: To assess the responses of the superficial peripapillary retinal vessel density (VD) and prelaminar flow index (PLFI) to topical Rho-assisted coiled-coil forming protein kinase (ROCK) inhibitor ripasudil and alpha-2 agonist brimonidine using optical coherence tomography angiography. METHODS: This is a prospective, non-randomized, comparative cohort study. We studied the response of optical coherence tomography angiography (OCTA) parameters to drugs in 24 eyes treated with ripasudil and 23 eyes treated with brimonidine at the Sensho-kai Eye Institute. After division by the signal strength (SS), we compared the responses of peripapillary VD/SS and PLFI/unit area (UA)/SS to topical eye drops in eyes with primary open-angle glaucoma (POAG) and ocular hypertension (OH). RESULTS: In the superficial peripapillary retina, VD/SS increased significantly in the ripasudil-treated eyes (12.5 ± 21.7%, P = 0.018), but not in the brimonidine-treated eyes (- 2.0 ± 13.8%, P = 0.484). In the deeper area of the optic disc, the changes in the PLFI/UA/SS in the brimonidine-treated eyes (+ 0.9 ± 8.9%, P = 1.00) and ripasudil-treated eyes (- 1.3 ± 8.5%, P = 0.241) were not significant. Multivariate discriminant analysis showed that the change in the peripapillary VD/SS was the most important parameter (P = 0.0186) for differentiating ripasudil- and brimonidine-treated eyes. CONCLUSIONS: The topical ROCK inhibitor ripasudil enhanced the peripapillary VD in POAG and OH, whereas the alpha-2 agonist brimonidine did not. The PLFI did not respond to either drug.

Consequences of Clot Formation and Hyphema Post-Internal Trabeculotomy for Glaucoma.

PRCIS: Clot formation and hyphema following internal trabeculotomy represent distinct clinical entities. The eyes with clot formation exhibited a more pronounced postsurgical intraocular pressure spike, longer residual intracameral bleeding, and a higher risk of reoperation. PURPOSE: The aim of this study was to investigate the consequences of clot formation and hyphema in the anterior chamber after internal trabeculotomy. MATERIALS AND METHODS: In this retrospective interventional comparative study, we investigated the surgical outcomes of internal trabeculotomy in 142 eyes of 142 patients at Sensho-kai Eye Institute. RESULTS: Concurrent clot formation and L≥2 hyphema (height of hyphema ≥1 mm) was observed in 22 eyes. In these cases, the postsurgical IOP was 29.3 mm Hg at 1 week, significantly higher than the 16.1 mm Hg in eyes that had L≥2 hyphema but without clot formation ( P =0.0002). However, the 1-week postsurgical IOP in L≥2 hyphema and clot (-) eyes, which measured 16.1 mm Hg was not significantly greater than that in L<2 hyphema and clot (-) eyes, which measured 18.7 mm Hg ( P =0.162). Thus, clot formation was identified as a significant factor contributing to high postsurgical IOP at 1 week. The resolution time for anterior chamber bleeding in eyes with concurrent clot formation and L≥2 hyphema was 12.3 days, longer than the 5.8 days observed in L≥2 hyphema eyes without clot formation ( P =0.016). Among the 22 eyes with concurrent L≥2 hyphema and clot formation, 8 required anterior chamber washout. Three of the 10 eyes that underwent washout necessitated additional trabeculectomy, a rate significantly higher than that in nonwashout eyes ( P <0.001). CONCLUSIONS: After internal trabeculotomy, the sequelae of concurrent clot formation and L≥2 hyphema in the anterior chamber were more severe than those of simple hyphema without clots. Clot formation negatively affected postoperative IOP.

Trends in the National Ophthalmological Healthcare Focusing on Cataract, Retina, and Glaucoma Over 15 Years in Japan.

To assess the trends in ophthalmic healthcare, especially those of cataract, vitreo-retinal diseases, and glaucoma, the national data from the Japanese Ministry of Health, Labour and Welfare, which recorded medical practices for 126.1 million citizens, were studied for 15 years. The volume and expenses of cataract surgeries increased during this period; however, non-surgical expenses decreased. As a result, the total national cataract healthcare expenses decreased over the 15-year period. The volume of vitrectomies increased from 2007 to 2013. After introduction of anti-vascular endothelial growth factor (VEGF) injections, the number of injections increased 8.4 times from 2010 to 2021, while the volume of vitrectomy and retinal photocoagulation declined after 2019 and 2017, respectively. Minimally invasive glaucoma and long-tube shunt surgeries began to increase in 2015 and 2014, respectively. This trend contrasts with the decrease in trabeculectomies after 2019. The coronavirus disease-19 pandemic caused a 30.9% decrease in ophthalmological surgery expenses in 2020. The decreases in volume and expense were greater for cataract surgeries than for other surgeries. The pandemic had a stronger impact on ophthalmological healthcare than that on general medical healthcare. Advancements in technology and methodology have led to cost savings in national cataract healthcare, vitrectomy, and retinal photocoagulation while caused increase in the volume and expenditure of glaucoma surgeries and anti-VEGF injections over a span of 15 years in Japan.

Different patterns in the corneal endothelial cell loss after pars plana and pars limbal insertion of the Baerveldt glaucoma implant.

PURPOSE: To assess corneal endothelial cell (CE) loss after pars plana (PP) and pars limbal (PL) insertion of a Baerveldt glaucoma implant (BGI). DESIGN: Retrospective multicenter interventional comparative study. METHODS: We studied central CE loss for 5 years after BGI surgery in 192 eyes. RESULTS: The prevalence of bullous keratopathy (BK) was greater in the PL cohort than in the PP cohort (P = .003). The CE loss after simultaneous PP vitrectomy and tube insertion into the vitreous cavity was 11.9% in the first year, which was greater than that of 2.9% in eyes where the tube was inserted simply into the vitreous cavity after a prior vitrectomy (P = .046). The annual percentage CE loss after the first year decreased unidirectionally in both of those groups and was 1.3% and 1.0% in the fifth year, respectively (P < .001). For limbal insertion, the CE loss in the simple PL cohort was biphasic, decreasing from 10.5% in the first year to 7.0% in the fifth year. Simultaneous cataract and BGI surgery enhanced the CE loss slightly in the first year in the PP and PL cohorts to 13.0% and 14.0%, respectively. However, these increases were not significant (P = .816 and .358, respectively). Low preoperative CE density (P < .001) and insertion site (P = .020) were significant risk factors for the development of BK. CONCLUSIONS: CE loss in the PL and PP cohorts was biphasic and unidirectional, respectively. The difference in annual CE loss became evident over time. PP tube implantation may be advantageous when the preoperative CE density is low.

Impact of high myopia on the performance of SD-OCT parameters to detect glaucoma.

BACKGROUND: The aim was to evaluate the effects of high myopia on spectral-domain optical coherence tomography (SD-OCT) parameters, as well as on their ability to detect glaucoma. METHODS: Ninety-three glaucoma and 86 non-glaucoma patients were divided into highly myopic group (HMG; 90 subjects, ≤ -5 diopters [D]) and emmetropic (EG; 89 subjects, spherical equivalent ≤1 D and ≥ -1D) groups in this cross-sectional comparative study. Macular ganglion cell complex (GCC) and circumpapillary retinal nerve fiber layer (cpRNFL) measurements obtained from the algorithms of the SD-OCT system were compared. The effects of refractive errors and glaucoma were assessed using a generalized linear model, after adjusting for age. A receiver operating characteristic curve was constructed for each parameter, and the areas under the curves (AUCs) were compared. RESULTS: The all cpRNFL measurements were significantly related to both refractive errors and glaucoma, while all GCC parameters were not significantly related to the refractive errors. The AUC for average GCC thickness was similar between the HMG (AUC, 0.935) and EG (AUC, 0.933), while the AUC for average cpRNFL thickness differed significantly (p = 0.028) between the HMG (AUC, 0.827) and EG (AUC, 0.939). CONCLUSIONS: Macular GCC parameters showed good ability to detect glaucoma in both groups, whereas the ability of cpRNFL measurement in HMG subjects was inferior to that in EG subjects. Assessment of GCC parameters is a useful technique complementary to cpRNFL thickness assessment, for clinically evaluating patients with concomitant glaucoma and high myopia.

Development and Application of a New T-shaped Internal Trabeculotomy Hook (T-hook).

Purpose: We introduce a newly designed T-shaped internal trabeculotomy hook and compare its surgical outcomes with those of Kahook dual blade (KDB) surgery. Patients and Methods: One eye each of seventeen and sixty-one patients underwent T-hook and KDB surgeries, respectively. Post-surgical intraocular pressure (IOP), medications, visual acuity, and prevalence of IOP spikes and hyphema were compared between the two cohorts. Results: The utility of the T-hook was excellent and enabled the easy opening of the Schlemm's canal. The pre-surgical IOP of 25.6 ±7.5 mmHg in the T-hook cohort decreased to 14.1 ± 4.3 (-41.2% reduction) and 15.0 ± 3.1mmHg (-39.3% reduction) at 3 (P<0.001) and 6 months (P=0.003), respectively. Pre-surgical medications of 2.8 decreased to 2.3 and 2.0 medications, respectively, at 3 and 6 months. The best-corrected visual acuity (BCVA) improved from the pre-surgical logarithm of the minimum angle resolution (logMAR) of 0.148 to -0.012 at three months (P=0.036,). While the pre-surgical IOP of 24.9±4.3 mmHg in the KDB cohort decreased to 16.5±5.7 mmHg (-35.5%, P<0.001) and 16.1±3.4 mmHg (-33.5%, P<0.001) at 3 and 6 months, respectively. Reduction in medications at 3- and 12-month timepoints (from 2.8 to 1.7 and 1.7, respectively; P<0.001) and improvement in BCVA at three months (from 0.106 to -0.025 logMAR, P<0.001) were also significant. There was no difference between the T-hook and KDB cohorts in terms of the pre-surgical IOP (P=0.15) and post-surgical IOP at 1 (P=0.27), 3 (P=0.17), 6 (P=0.47), and 12 months (P=0.11, Mann-Whitney U-test). The prevalence of a post-surgical IOP spike in the T-hook and KDB cohorts was 41.2% and 47.5%, and that of post-surgical hyphema was 17.6% and 26.2%, respectively. Conclusion: The novel T-hook was easy to use and was as useful as the KDB device in performing internal trabeculotomy.

Ocular Hypotension and Epiretinal Membrane as Risk Factors for Visual Deterioration Following Glaucoma Filtering Surgery.

PRECIS: Postsurgical hypotension at 1 week and the presence of an epiretinal membrane (ERM) were significant risk factors for the deterioration of postsurgical visual acuity (VA) at 3 and 12 months, respectively. PURPOSE: The purpose of this study was to assess the effects of an ERM and postsurgical hypotension <6 mm Hg at 1 week on postsurgical VA loss. PATIENTS AND METHODS: A total of 69 patients (69 eyes) who underwent trabeculectomy with adjunctive mitomycin C between 2017 and 2019 (mean follow-up period: 22.8 mo) were enrolled, and 14 parameters that could be associated with the deterioration of VA at 3 and 12 months were studied. RESULTS: There was a significant association between VA loss at 3 months and postsurgical intraocular pressure at 1 week (P=0.006 by multiple regression) and hypotony maculopathy (P=0.024 by Fisher exact test). However, this association was lost at 12 months. Instead of postsurgical hypotension, the presence of an ERM was significantly associated with VA loss at 12 months (P=0.035 by Fisher exact test, and P=0.023 by logistic regression). CONCLUSIONS: Postsurgical hypotension at 1 week was significantly associated with mid-term, but not long-term, postsurgical VA loss. The presence of an ERM, which was not a risk factor for mid-term acuity loss, was a significant risk factor for VA loss at 12 months.

Turn Back Elevation of Once Reduced IOP After Trabeculotomy Ab Externo and Kahook Dual Blade Surgeries Combined with Cataract Surgery.

PURPOSE: To evaluate the surgical outcome of internal trabeculectomy by Kahook dual blade (KDB) with that of external trabeculotomy, each combined with phaco-lensectomy and intraocular lens implantation (Phaco). PATIENTS AND METHODS: This is a retrospective comparative study. The primary and secondary outcome measures are postsurgical intraocular pressure and postsurgical hyphema. One eye each of 76 primary open angle glaucoma (POAG), pseudoexfoliation glaucoma (PEG) and ocular hypertension (OH) patients underwent external phaco-trabeculotomy, and that of 40 POAG, PEG and OH patients underwent phaco-KDB surgery. RESULTS: Reduction of the intraocular pressure (IOP) by phaco-KDB at one and two years was 28.4 and 27.8%, respectively, and was not significantly different from that by external phaco-trabeculotomy of 32.7% (P=0.256) and 31.5% (P=0.468), respectively. Three months postsurgical IOP after phaco-KDB and external phaco-trabeculotomy was 16.1 and 15.9 mmHg, respectively. There was a significant turn back elevation of once reduced IOP to 17.1 (P=0.0207) and 17.0 mmHg (P=0.0096) at 24 months, respectively. There were no differences in success probability to achieve IOP below 17 mmHg (P=0.120), 21 mmHg (P=0.719) and >20% IOP reduction (P=0.309) with medication(s) at two years between the phaco-KDB and external phaco-trabeculotomy cohorts. Younger age was a significant (P<0.001) risk factor for failure; however, presurgical IOP (P=0.466), the type of surgery (P=0.219) and presence of postsurgical IOP spike (P=0.737) were not significant risk factors by the Cox proportional hazard model. Hyphema and spike of the IOP in phaco-KDB and external phaco-trabeculotomy cohorts were 40% and 88% (P<0.001), and 53% and 41% (P=0.238), respectively. CONCLUSION: The IOP reduction by the phaco-KDB was equivalent to that by external phaco-trabeculotomy up to two years. In both cohorts, once reduced postsurgical IOP tend to increase up to 24 months.

Long axial length as risk factor for normal tension glaucoma.

BACKGROUND: The high prevalence of normal tension glaucoma (NTG) in the Japanese requires special screening tests other than measurements of only the intraocular pressure (IOP). This study was carried out to determine whether there is a significant association between the axial length of the eye and the presence of NTG. METHODS: We reviewed the medical records of all patients who were scheduled to undergo cataract surgery alone or combined with glaucoma surgery at the same time. There were 87 patients with NTG, 137 with POAG, and 978 non-glaucomatous control cases. The axial length, IOP, curvature of the anterior corneal surface, age, and gender were determined at the time of the operation. If both eyes had surgery, data from only the right eyes were analyzed. An association of these parameters with NTG and POAG was analyzed by logistic regression analysis. The three groups were analyzed for differences in the axial length using the Kruskal-Wallis test followed by the Mann-Whitney U test. RESULTS: The axial length was significantly associated with NTG (odds = 1.24, P = 0.002) and POAG (odds = 1.28, P = 0.001). The incidence of either POAG or NTG was significantly higher in patients with axial lengths >or=25.0 mm (odds = 2.29, P < 0.001, Fisher's exact test). The age at the time of cataract surgery was weakly but significantly correlated negatively with the axial length (r = -0.24, P < 0.001, Pearson's correlation coefficient test). Men had significantly longer axial lengths than women. CONCLUSIONS: Long axial lengths can be considered a risk factor for NTG and POAG, and patients with long axial lengths need to be carefully examined for glaucoma.

Impact of diabetic retinopathy on quantitative retinal nerve fiber layer measurement and glaucoma screening.

PURPOSE: To investigate the impact of diabetic retinopathy on quantitative retinal nerve fiber layer (RNFL) assessment and diagnostic power for glaucoma by scanning laser polarimetry (GDx-VCC) and optical coherence tomography (StratusOCT). METHODS: The individual RNFL parameters of GDx and OCT were obtained for 170 eyes (one eye from each of 170 subjects [45 healthy, 47 glaucoma, 40 diabetes, and 38 glaucoma with diabetes]) and were compared among the four groups. Diabetic eyes had mild to moderate nonproliferative diabetic retinopathy (NPDR) without maculopathy. In glaucomatous eyes with or without diabetes, the ability to discriminate glaucoma was assessed by the areas under the receiver operating characteristic curves (AUROCs) and the sensitivities at more than 80% and 90% of specificities for each technique. RESULTS: Using GDx-VCC, significant differences (P < 0.05) in RNFL measurement parameters were found for all comparisons except those between glaucomatous eyes with diabetes and without diabetes. StratusOCT parameters did not detect significant differences between age-matched healthy and diabetic eyes. Among the parameters included, the nerve fiber indicator (NFI) of GDx-VCC and the inferior quadrant thickness (IQT) of StratusOCT had the largest AUROCs and sensitivities at specificities greater than 80%: NFI (0.912, 86%) and IQT (0.902, 85%) in glaucomatous eyes with diabetes; NFI (0.935, 92%) and IQT (0.921, 91%) in simple glaucomatous eyes. CONCLUSIONS: Mild to moderate NPDR causes a quantitative discrepancy in RNFL measurements between GDx-VCC and StratusOCT in simple diabetic eyes. However, mild to moderate glaucomatous optic neuropathy can be highly discriminated by the two imaging devices in eyes with diabetic retinopathy.

Assessment of true intraocular pressure: the gap between theory and practical data.

A precise assessment of the intraocular pressure (IOP) is crucial for diagnosis and decision making regarding treatment modalities in patients with glaucoma. Recent epidemiologic studies show that a difference of only 1 mm Hg in the mean IOP may be critical enough to determine the visual field prognosis in patients with glaucoma. However, the Goldmann applanation tonometer, which is current gold standard, is not precise enough to measure the true IOP within an error of 1 mm Hg. There are many clinically proposed correction algorithms to correctly measure IOP. However, corrections using only the central corneal thickness and curvature may not be sufficient in each individual case. In this article, previously reported theoretical equations about the effects of corneal topography, modulus of elasticity, and tear film on Goldmann applanation tonometric IOP readings were reviewed, and their discrepancies with clinical or experimental data were analyzed. Thereafter, new tonometers such as the dynamic contour tonometer, the rebound tonometer, and the ocular response analyzer were compared with the Goldmann applanation tonometer and other popular tonometers.

[Clinical study of the pars plana Ahmed glaucoma valve implant in refractory glaucoma patients].

PURPOSE: To evaluate the effect of pars plana implantation of the Ahmed glaucoma valve on refractory glaucoma. METHOD: Five patients (5 eyes) (3 men, 2 women) were fitted with the Ahmed glaucoma valve. Mean age was 51.8 21.3 years, and mean follow-up was 9.4 +/- 2.6 months. Among the 5 eyes studied, 4 eyes were in neovascular glaucoma patients. Of these 4 eyes, 2 eyes were in diabetic retinopathy patients and 2 eyes were in a patient with central retinal vein occlusion. The remaining eye was in a developmental glaucoma patient. As a surgical procedure after pars plana vitrectomy, the inlet tube of the Ahmed glaucoma valve was placed in the posterior chamber. RESULT: The mean preoperative IOP of 46.8 +/- 15.7 mmHg (30-64 mmHg) under maximum tolerable medication was reduced to 16.0 +/- 2.0 mmHg (14-19 mmHg) after surgery. Postoperative visual acuity improved in 3 eyes, and the mean visual acuity in these eyes improved from 0.05 +/- 0.09 (sl.-0.07) to 0.17 +/- 0.3(0-0.7). A reduction in visual acuity was observed in 2 eyes; in one, due to retinal detachment, and in the other, due to transient high IOP and vitreous hemorrhage. The visual acuity improved in 60% of patients and the IOP controlled in 80% of patients. CONCLUSION: The implantation of the Ahmed glaucoma valve for refractory glaucoma was effective in our study.

Phacoviscocanalostomy versus cataract surgery only in patients with coexisting normal-tension glaucoma: midterm outcomes.

PURPOSE: To compare the midterm efficacy and safety of phacoviscocanalostomy (viscocanalostomy, phacoemulsification, and intraocular lens [IOL] implantation) and cataract surgery (phacoemulsification and IOL implantation) in patients with normal-tension glaucoma (NTG) and cataract. SETTING: Sensho-kai Eye Institute, Kyoto, Japan. METHODS: Thirty-one eyes had phacoviscocanalostomy, and 35 eyes had uncomplicated cataract surgery only. The intraocular pressure (IOP), postoperative antiglaucoma medications, and visual outcomes were compared between groups. RESULTS: The mean follow-up was 34.9 months+/-19.8 (SD) (range 7 to 78 months). At 36 months, the mean preoperative IOP and postoperative IOP were 17.2+/-1.5 mm Hg and 14.1+/-1.6 mm Hg, respectively, in the phacoviscocanalostomy group and 16.7+/-1.4 mm Hg and 15.6+/-3.4 mm Hg, respectively, in the cataract surgery only group. The differences between groups were significant at all time points (P<.05). The success probabilities of the phacoviscocanalostomy group achieving 20% and 30% IOP reductions with (or without) medications were 78.5% (67.4%) and 35.5% (37.4%) at 24 months and 58.0% (44.2%) and 28.0% (26.6%) at 48 months, which were significantly better than the probabilities in the cataract surgery only group, which were 16.0% (9.5%) and 5.7% (2.9%) at 24 months (P<.001 for each comparison, Kaplan-Meier life-table analysis with log-rank test). Based on the modified Aulhorn-Greve classification, the visual acuity and visual fields did not deteriorate in the phacoviscocanalostomy group; the visual fields deteriorated in 6 eyes in the cataract surgery only group during the follow-up (P=.024). CONCLUSION: Phacoviscocanalostomy lowered IOP and maintained postoperative visual outcomes; it was safe and effective in elderly patients with coexisting NTG and cataract.

Prospective evaluation of factors associated with post-LASIK corneal birefringence with scanning laser polarimetry.

PURPOSE: To identify factors that affect corneal birefringence, such as the corneal polarization axis (CPA) and corneal polarization magnitude (CPM), after laser in situ keratomileusis (LASIK) using scanning laser polarimetry with a variable corneal polarization compensator. METHODS: The CPA and CPM from 42 patients (42 eyes) who underwent LASIK and 24 normal untreated subjects (24 eyes) were measured 1 week before and 1 week after LASIK. Changes in the CPA and CPM after LASIK were studied using Student t test and Pearson correlation coefficient. RESULTS: In the LASIK group, the post-LASIK CPA and CPM significantly changed, whereas both values did not change in normal subjects. Among 5 candidate factors [preoperative CPA (pre-CPA), preoperative CPM (pre-CPM), age, change in corneal curvature, and ablation depth], the change in CPA was significantly correlated with the pre-CPA (r=-0.793) and pre-CPM (r=0.339). The change in CPM was correlated with the pre-CPA (r=-0.455) and pre-CPM (r=-0.411). Over 83% case of postoperative corneal birefringence can be explained by only 2 parameters with regression analysis. CONCLUSIONS: The pre-CPA and pre-CPM are strongly associated with LASIK-induced changes in CPA and CPM. Variations in age, changes in corneal curvature, and ablation depth do not contribute to changes in either parameter.