Ab-externo cyclodialysis enhanced trabeculectomy for intractable post-penetrating keratoplasty glaucoma.

PURPOSE: To evaluate the efficacy of cyclodialysis-enhanced Mitomycin c (MMC) trabeculectomy in post-keratoplasty glaucoma. DESIGN: Prospective, non-comparative, interventional case series. METHODS: A total of 45 eyes of 45 consecutive patients with refractory glaucoma after penetrating glaucoma underwent a cyclodialysis-augmented trabeculectomy with MMC. The visual acuity, intraocular pressure (IOP), corneal clarity, and graft failure were evaluated over a minimum follow-up of 2 years. RESULTS: The mean age of the patients was 55.4+/-9.4 years. The cyclodialysis-augmented MMC trabeculectomy procedure resulted in a mean reduction of IOP from 38.9+/-3.9 mmHg (95% confidence interval (CI) 35.9-42.2) at baseline to 11.3+/-2.8 mmHg (95% CI 9.5-12.9), at final follow up (P=0.002). Blebs were avascular, diffuse, and extended posteriorly. Postoperative UBMs revealed the presence of a cyclodialysis with a small associated suprachoroidal effusion and a subconjunctival filtering bleb in all cases. CONCLUSIONS: Cyclodialysis-augmented MMC trabeculectomy provides a safe and effective method of lowering IOP in intractable glaucoma following penetrating keratoplasty, without compromising the corneal graft survival and clarity.

Prospective, long-term evaluation of steroid-induced glaucoma.

PURPOSE: To evaluate the intraocular pressure (IOP) after cessation of steroid use in steroid-induced glaucoma and its control with medication or surgery. METHODS: Thirty-four eyes of 34 patients having steroid-induced glaucoma were prospectively evaluated after cessation of steroid for IOP, visual acuity, and optic disc status at 3 months, and every 3 months for 18 months. RESULTS: Topical steroid use (73.5%) was the most frequent cause for glaucoma. The baseline IOP was 35.47+/-12.59 mmHg. The baseline vertical cup-disc ratio correlated with duration of steroid use (P=0.014) and the baseline IOP (P<0.0001). In 25 patients (73.5%), IOP could be controlled by topical medications alone, whereas nine patients (26.5%) required surgery. The mean baseline IOP in eyes requiring surgery was 49.67+/-13.28 mmHg and in eyes managed medically, 30.36+/-7.51 mmHg (P=0.002). The vertical cup-disc ratio in surgically treated patient was 0.87+/-0.13:1 as compared to 0.71+/-0.15:1 (P=0.012) in the medically treated group. At 6, 12, and 18 months follow-up, 22 (64.7%), 33 (97.1%), and all 34 (100%) patients were off treatment, respectively. CONCLUSIONS: Patients with steroid-induced glaucoma, who were

Is the ISNT rule violated in early primary open-angle glaucoma--a scanning laser tomography study.

AIMS: To evaluate the relevance of the ISNT rule with reference to the optic nerve head, in differentiating normal and early glaucoma eyes and neuroretinal rim (NRR) area ratios as measures of glaucomatous optic neuropathy by confocal scanning laser ophthalmoscopy (Heidelberg retina tomography (HRT) II). METHODS: The study included 136 control eyes and 63 eyes of early primary open-angle glaucoma. Each patient underwent a complete ophthalmic examination, HRT II (software 2.01) and achromatic automated perimetry using the Humphrey field analyzer Full threshold program 30-2 or 24-2. Topographic HRT parameters (disc area and rim area) were compared between the groups. To assess the statistical significance of differences between the study groups, the Student's t-test was used. RESULTS: The ISNT rule was applicable in 71% of normal eyes and 68% of early glaucoma eyes. The superior to inferior area ratio was 0.96+/-0.01 in the normal group and 0.90+/-0.02 in the glaucoma group. There was a loss of approximately a quarter of the NRR in the inferotemporal and superotemporal quadrants. The inferonasal sector showed the least loss of NRR (4.34%). CONCLUSION: The inferior NRR is marginally wider than the superior NRR in about 2/3 of normal eyes, but could not be clinically appreciated in many of these. The characteristic configuration of a normal optic disc with the rim width being greatest in the inferior disc region followed by the superior disc region was maintained even in most patients with early glaucoma.

Study of biometric parameters in family members of primary angle closure glaucoma patients.

OBJECTIVES: To measure ocular biometric parameters in all possible untreated family members of index primary angle closure glaucoma (PACG) patients and to correlate these values among affected, unaffected, and suspected family members. METHODS: Anterior chamber depth (ACD), axial length (AL), lens thickness (LT), relative lens position, and central corneal thickness (CCT) were measured in first- and second-degree relatives of index patients. These biometric parameters were compared among the relatives and index patients as well as among affected, unaffected, and suspected family members. RESULTS: Of the 108 family members included in the study, 34 (31.6%) were affected with primary angle closure, 19 (17.6%) were suspect, and 55 (50.7%) were unaffected family members. In comparison to index cases, ACD was 14.56% more in affected, 21.7% more in primary angle closure suspects and 34.92% more in unaffected family members. LT was 10.73, 11.1, 16% less and AL was 0.11, 3.53 and 5.37% more in affected, suspected, and unaffected family members, respectively. Lens position and CCT were not statistically different in the various subgroups. CONCLUSIONS: ACD is narrowest, lens thickest, and AL shortest in family members affected with PACG compared to suspected and unaffected members. Although LT and ACD could change with advancing age, AL appears to be a marker to identify members at risk of angle closure glaucoma.

Does an iridotomy provide protection against narrowing of the anterior chamber angle during Valsalva maneuvre in eyes with primary angle closure.

PURPOSE: To evaluate changes at the anterior chamber angle during Valsalva manoeuver, in eyes having primary angle closure (PAC) and a patent laser peripheral iridotomy. METHODS: Twenty-three eyes of 23 consecutive patients underwent a recording of applanation tonometry, measurement of the anterior chamber angle recess, angle opening distance, iris thickness, anterior chamber depth, and pupil size on ultrasound biomicroscopy before and during the Valsalva maneuver. The Valsalva manoeuver was standardized to a pressure of 40 mmHg for 15 s, using a manometer. RESULTS: The mean baseline intraocular pressure changed from 18.86+3.79 to 26.73+4.73 mmHg during Valsalva, (P<0.0001). The anterior chamber angle recess narrowed from 16.62+6.24 to 6.5+4.02 degrees (P<0.0001). There was a significant increase in the thickness of the ciliary body from 0.92+0.25 to 1.17+0.31 mm (P=0.0006) and in the iris thickness from 0.47+0.17 to 0.57+0.11 mm (P=0.007). A significant increase in pupillary diameter (P=0.008) and a decrease in the angle opening distance (P<0.0001) also occurred during Valsalva, whereas there was no significant change in the anterior chamber depth (P=0.056). The angle recess during Valsalva had a positive correlation with the baseline anterior chamber angle (r=0.41, P=0.05) and a negative correlation with the ciliary body thickness (r=-0.52, P=0.046). CONCLUSIONS: The induction of Valsalva maneuver in day-to-day activities can lead to significant anterior segment angle shallowing and can lead to progression from the PAC stage to primary angle closure glaucoma in such predisposed eyes. The presence of a patent laser iridotomy may not prevent irido trabecular apposition during the Valsalva maneuver.

Evaluation of efficacy and safety of daunorubicin in glaucoma filtering surgery.

PURPOSE: To evaluate the intraocular pressure (IOP)-lowering effect and ocular side effects of daunorubicin (DNR) in drug-modulated trabeculectomy. METHODS: A prospective pilot study was conducted in which 21 Asian patients of Indian origin with high risk factors for failure of trabeculectomy were recruited. An approval from research ethics committee and an informed consent from every patient included in the study were obtained. DNR, an antimetabolite with known antifibroblastic action was used intraoperatively. A limbus-based conjunctival flap followed by conventional trabeculectomy was performed in all eyes. During trabeculectomy, a cellulose sponge soaked in 0.2 mg/ml DNR was applied for 3 min at the proposed site of trabeculectomy before preparation of the partial thickness scleral flap. A regular follow-up was carried out for 1 year where parameters including visual acuity, IOP by applanation tonometry, and slit lamp examination were performed on each visit. An IOP of 21 mmHg or less was taken as criteria for success. RESULTS: Following DNR trabeculectomy, the IOP was lowered from baseline preoperative value of 36.19+/-5.9 to 16.05+/-2.52 mmHg at the end of 1 year. Success rate of 81% (17 out of 21 patients) was noted. None of the patients developed corneal epithelial toxicity, hypotony maculopathy, or choroidal detachment. CONCLUSION: The authors feel that intraoperative daunorubicin is safe and effective in lowering IOP in high-risk surgical cases of glaucoma. However, a much larger cohort study over a considerable number of years will eventually demonstrate its safety.

Corneal topographic response to intraocular pressure reduction in patients with vernal keratoconjunctivitis and steroid-induced glaucoma.

PURPOSE: To study the corneal topographic response to IOP reduction in vernal keratoconjunctivitis (VKC) with steroid-induced glaucoma. METHODS: A total of 42 eyes of 21 patients with VKC and steroid-induced glaucoma (Group I) and 66 eyes of 33 patients with VKC without glaucoma (Group II) underwent an evaluation by Orbscan topography. In eyes with glaucoma, the IOP was controlled medically and the corneal topography was repeated at 3 months to evaluate effect on corneal parameters. RESULTS: The mean baseline IOP was 36.40+/-13.08 mmHg in Group I, 14.67+/-4.62 mmHg in Group II (P<0.0001). The IOP after treatment at 3 months follow-up was 15.00+/-5.41 mmHg in Group I (P<0.0001). In Group I, the mean maximum Sim K decreased from 44.86+/-3.21 D to 43.87+/-2.62 D (P=0.031) and mean posterior corneal elevation decreased from 64.9+/-22.36 microm to 35.7+/-28.91 microm at 3 months after reduction of IOP (P=0.001). There was a significant positive correlation between the reduction in the IOP and the decrease in the posterior corneal elevation (r=0.664, P=0.001). CONCLUSION: Eyes with VKC with and without glaucoma have similar corneal topography. Increased IOP associated with steroid-induced glaucoma and VKC may contribute to an increase in the corneal curvature and posterior corneal elevation. These changes may be reversed by a reduction in the IOP with medical therapy.

Comparison of ultrasound biomicroscopic parameters after laser iridotomy in eyes with primary angle closure and primary angle closure glaucoma.

PURPOSE: To study changes in anterior segment morphology after laser peripheral iridotomy (LPI) in primary angle closure (PAC) and primary angle closure glaucoma (PACG) using ultrasound biomicroscopy (UBM). METHODS: Ninety-three eyes of 93 patients underwent anterior segment evaluation including gonioscopy, disc evaluation with + 90D lens, applanation intraocular pressure, and standard achromatic perimetry. UBM was performed before and 2 weeks after Nd:YAG LPI to measure the trabecular-iris angle (TIA), the angle-opening distance (AOD 250/500), and the central anterior chamber depth (ACD). RESULTS: The superior TIA widened from a mean of 7.54+/-3.15 to 15.66+/-6.69 degrees (P=0.0001), the inferior TIA increased from a mean of 9.0+/-4.7 to 15.9+/-6.8 degrees (P=0.0001) after LPI in PAC. In PACG, the mean superior angle changed from 4.55+/-2.5 to 6.12+/-3.8 degrees (P=0.4) and the inferior angle increased from 4.75+/-2.0 to 7.9+/-3.7 degrees (P=0.1). The mean ACD increased from 2.19+/-0.36 to 2.30+/-0.36 mm in PAC group (P=0.0003), with no significant change seen in the PACG group (1.79+/-0.32 vs 1.82+/-0.33 mm, P=0.13). CONCLUSION: LPI leads to a widening of the anterior chamber angle and a deepening of the anterior chamber in eyes with PAC. It does not significantly change any anterior segment parameters in eyes with PACG.

An evaluation of the darkroom prone provocative test in family members of primary angle closure glaucoma patients.

PURPOSE: To compare ocular biometric parameters with darkroom prone provocative test (DRPPT) in family members of primary angle closure glaucoma (PACG) patients. METHODS: One hundred and forty-nine family members of 46 PACG patients underwent ocular examination included slit lamp biomicroscopy, gonioscopy, fundus examination using +90 D lens, Goldmann applanation tonometry, darkroom prone provocative test, perimetry on Humphrey's field analyzer II and optic disc evaluation using HRT II. Ultrasonic ocular biometry and the DRPPT were then performed. IOP>or=8 mmHg rise from baseline with iridocorneal touch was considered as a positive test. RESULTS: Of the 149 family members examined, 55 (36.9%) were found to have PACG. Forty (72.7%) of these had subacute PACG and 15 (27.3%) were found to have chronic PACG. Thirty-nine (70.3%) of the affected members showed a positive DRPPT. Mean anterior chamber depth (ACD) was 2.03+/-0.3, 2.3+/-0.4, 2.7+/-0.3 mm (P=0.0001) and mean lens thickness was 4.41+/-0.39, 3.99+/-0.5, 3.93+/-0.4 mm (P=0.0001) in DRPPT positives, borderlines and negatives respectively. ROC curve (ACD) plotted showed cutoff value of 2.07 mm (sensitivity 88.57%) for screening. CONCLUSION: Anterior chamber is shallowest, lens is thickest and axial length is shortest in affected and DRPPT positive, family members of PACG patients.

Comparative evaluation of diode laser trabeculoplasty vs frequency doubled Nd : YAG laser trabeculoplasty in primary open angle glaucoma.

AIMS: To evaluate the efficacy of diode laser trabeculoplasty (DLT) and frequency doubled Nd : YAG laser trabeculoplasty (YLT) in primary open angle glaucoma (POAG). METHODS: A total of 52 eyes of 35 patients with POAG were included. In all, 25 eyes underwent DLT (Group I) and 27 eyes underwent YLT (Group II). IOP, gonioscopy and visual fields were evaluated before and 3, 6, and 9 months and 1 year after the laser. An IOP<21 mmHg without medications or a decrease in the number of glaucoma medications with no progression of disc and field changes was considered a success. RESULTS: The mean age of patients in Group I was 57.72+/-8.1 years and the patients in Group II had a mean age of 59.85+/-7.76 years. The mean prelaser IOP was 24.93+/-1.49 mmHg and 25.36+/-1.57 mmHg. The mean IOP after DLT at 12 months follow-up was 18.0+/-0.93 mmHg and after YLT was 18.6+/-1.52 mmHg. The reduction of IOP was statistically significant in both the groups at 3, 6, 9, and 12 months (P<0.001), however there was no significant difference between the two groups. Success rates in both groups were similar, 92% in Group I and 92.6% in Group II. CONCLUSIONS: DLT and Fd YLT are equally effective in controlling IOP in eyes with POAG.

Utility values among glaucoma patients: an impact on the quality of life.

AIM: To ascertain utility values and associated quality of life with different severity and duration of glaucoma among Indian patients. METHODS: Utility values of 105 consecutive patients with primary glaucoma of at least 12 months' duration were evaluated in a cross sectional study. Utility values were ascertained in five groups using both the time-trade off and standard gamble methods: group 1 (best corrected visual acuity in the better eye of 6/9 or better), group 2 (best corrected visual acuity in the better eye of 6/18 to 6/12), group 3 (best corrected visual acuity in the better eye of 6/36 to6/24), group 4 (best corrected visual acuity in the better eye of 3/60 to 6/60), and group 5 (best corrected visual acuity in the better eye of 3/60 or worse). RESULTS: The mean utility value for the glaucoma group as a whole was 0.64 (SD 0.69; 95% confidence interval (CI), 0.58 to 0.70) with the time-trade off method and 0.86 (SD 1.00; 95% CI, 0.81 to 0.90) with the standard gamble method for a gamble of death and 0.97 (SD 1.00; 95% CI, 0.94 to 0.99) for a gamble of blindness. The mean utility results by the time-trade off method were as follows: group 1 = 0.66, group 2 = 0.66, group 3 = 0.62, group 4 = 0.55, and group 5 = 0.61. The utility value was much lower (0.46) in those with no formal education or only primary education compared to those with postgraduate education (0.75) (p = 0.038). Those patients with glaucoma of less than 5 years' duration had a utility score of 0.62 while those with glaucoma for more than 10 years had a score of 0.74 (p = 0.40). CONCLUSIONS: Visual acuity loss occurring secondary to glaucoma is associated with a substantial decrease in patient utility value (and quality of life) in a developing country like India. The utility value is directly dependent on the degree of visual acuity loss associated with the disease and educational status and not on the duration of disease, the number of medications, or the visual field indices.

Entropion uveae: early sphincter atrophy, signposting primary angle closure glaucoma?

PURPOSE: An easily recognized clinical marker for early changes of primary angle closure glaucoma (PACG) or eyes predisposed to angle closure is important so that timely laser iridotomy can prevent morbidity. Pupillary ruff changes, specifically appearance of entropion uveae (EU), are frequent in eyes with PACG. METHODS: Pupillary ruff was examined under magnification and EU, if present, was graded and correlated with gonioscopic grading and presence of peripheral anterior synechiae (PAS) in consecutive patients with primary open angle glaucoma (POAG), non-glaucomatous controls, and PACG of the subacute, acute, chronic symptomatic, and creeping angle closure glaucoma subgroups. RESULTS: No POAG eye had an abnormal pupillary ruff. A total of 86.7% of subacute PACG eyes and all eyes with acute and chronic PACG showed some grade of EU. Iridocorneal synechiae were more significantly correlated with EU than goniosynechiae (p<0.001). Meridian of iridocorneal but not iridotrabecular synechiae could be correlated with the meridian of EU. In age-matched patients EU was only present in eyes with steep iris configuration, with significant correlation with narrow angles and goniosynechiae. In the detection of PACG the presence of EU Grade I was 94.9% sensitive and 98.2% specific for PACG eyes compared to the gonioscopic picture of angle closure in occludable angles. Its positive predictive value was 91.4%. CONCLUSIONS: EU shows significant correlation with narrow angles, steep iris configuration, and PAS. Kinking of radial iris arteries during angle closure probably causes temporary ischemia, especially of end arteries supplying area of the pupil and sphincter pupillae. EU emerges as an easily observed, objective marker for PACG.

Peak pressures: crossover study of timolol and latanoprost.

PURPOSE: To compare the diurnal efficacy and action on peak intraocular pressures (IOP) of 0.005% latanoprost and 0.5% timolol as primary therapy in 60 eyes having dark brown irides with primary open angle glaucoma (POAG). METHODS: A prospective, comparative, observer-masked, crossover, interventional trial including the mean of both eyes of 30 patients with POAG who were randomly started on either latanoprost once daily or timolol twice daily. Three months after treatment with one drug, the second drug was substituted. A masked observer carried out diurnal assessments of IOP before the start of therapy and at 3 and 7 months. The fourth month was the washout period for the first drug. RESULTS: The average baseline IOP was 23.36 +/- 2.14 mm Hg, which was reduced by 8.8 +/- 2.2 mmHg with latanoprost (p < 0.01) and by 6.75 +/- 1.9 mm Hg with timolol (p = 0.01). The reduction was greater for latanoprost (p < 0.005). The average peak IOP at baseline was 27.6 +/- 2.22 mmHg. The effective fall in IOP at the time of new peaks in subsequent diurnal recordings of IOP compared to the baseline diurnal curve was 8.9 mm Hg with latanoprost (p < 0.005) and 5.77 mm Hg with timolol (p < 0.01). This difference in IOP reduction between the two drugs was statistically significant (p < 0.01). Latanoprost had a lower efficacy in peak IOP reduction in eyes with evening peak of IOP than in those with morning peak (p < 0.005). The efficacy of timolol was lower overall compared to latanoprost, but was similar in all circadian rhythms. The shift in timing of IOP peak was greater with latanoprost compared to timolol (4.34 hours vs -0.72 hours, p < .01). A total of 90% of patients on latanoprost and 33.3% on timolol achieved a reduction of > 30% in baseline mean IOP. The average of the trough IOP recorded in each of the individual baseline IOP curves was 19.05 +/- 2.05 mm Hg. CONCLUSIONS: Greater mean and peak IOP reduction was achieved with latanoprost compared to timolol. Dampening of the circadian rhythm was better with latanoprost. Latanoprost appears to be more effective than timolol at all points in time with greater efficacy in eyes with morning peaks compared to evening peaks.

Correlation between confocal scanning laser ophthalmoscopy and scanning laser polarimetry in open angle glaucoma.

PURPOSE: To correlate the findings of confocal scanning laser ophthalmoscopy and scanning laser polarimetry in diagnosed cases of glaucoma with established visual field defects. METHODS: A total of 53 diagnosed cases of primary open angle glaucoma that had at least two recorded of IOP more than 21 mm Hg on Goldmann applanation tonometry, open angles on gonioscopy and glaucomatous visual field defects on automated perimetry, were examined by confocal scanning laser ophthalmoscopy (HRT-II) and scanning laser polarimetry (GDx-NFA), in random order. RESULTS: The number on GDx advanced analysis had a significant (p < 0.05) correlation with the rim area (r = -0.279; p = 0.043), cup area (r = 0.311; p = 0.023) and the vertical cup: disc ratio (r = 0.376; p = 0.006). The correlation between HRT-II stereometric parameters and GDx advanced analysis parameters was significant (p < 0.05) for more parameters targeting the inferior pole of the disc than the superior pole. Numerically, the worst values of GDx parameters were associated with a worse result on Moorfields regression analysis, but there was poor agreement between the diagnostic labels like within or outside normal limits as obtained on GDx and HRT-II. CONCLUSIONS: Nerve fiber loss as detected on GDx correlates well with topographic optic nerve head changes as measured with the HRT-II. However, automated diagnosis on the two machines showed poor agreement.

Cumulative effect of risk factors on short-term surgical success of mitomycin augmented trabeculectomy.

CONTEXT: Risk factors for failure of trabeculectomy may have a cumulative effect on the outcome. AIMS: To study the effect of preoperative ocular risk factors on the surgical outcome of trabeculectomy augmented with 2 commonly used doses of Mitomycin C. SETTINGS AND DESIGN: In a prospective cohort study, cases were recruited over an 18 month period. 92 eyes of 83 patients with one to three known risk factors for failure of trabeculectomy underwent Mitomycin-C (MMC) augmented trabeculectomy. METHODS AND MATERIAL: Trabeculectomy was done with a randomly chosen MMC dose of 0.2 mg/ml or 0.4 mg/ml. All cases were followed up for a period of at least 3 months. Surgical success was defined as the lowering of intraocular pressure (IOP) below 21 mmHg during the follow up period. STATISTICAL ANALYSIS USED: Chi square test, paired t test, odds ratio, effect size. RESULTS: Eyes with two or three risk factors (out of aphakic glaucoma, failed trabeculectomy, neovascular glaucoma, post uveitic glaucoma, traumatic glaucoma, adherent leucoma, juvenile glaucoma, prolonged medical therapy, steroid induced glaucoma, post penetrating keratoplasty glaucoma and developmental glaucoma) had a significantly poorer surgical success rate (88% and 78%) than eyes with one risk factor (100%). 0.4 mg/ml MMC used sub-sclerally had a statistically similar effect on lowering the IOP as 0.2 mg/ml in all groups. The rate of complications was significantly higher in the 0.4 mg/ml subgroup. CONCLUSIONS: The presence of more than one preoperative ocular risk factor, affects the surgical success of MMC augmented trabeculectomy in high-risk cases. Because of the significantly higher rate of complications with the higher dose of MMC, this should be used sparingly, only in cases with more than two risk factors.

Role of argon laser trabeculoplasty as primary and secondary therapy in open angle glaucoma in Indian patients.

AIMS: To study the efficacy of argon laser trabeculoplasty (ALT) as a primary and secondary therapy in Indian patients with primary open angle glaucoma (POAG). METHODS: ALT was performed as a primary therapy in 40 eyes of 21 patients newly diagnosed with POAG (group I) and as a secondary therapy in 39 eyes of 21 patients who had been taking topical antiglaucoma medications for more than 1 year. The best corrected visual acuity, baseline intraocular pressure (IOP), diurnal variation of IOP, anterior chamber angles, and visual fields were the various parameters evaluated before and after performing ALT. Follow up visits were scheduled at 24 hours, 1 week, 1 month, 3 months, 6 months, and 1 year after the surgery. The patients were recalled at the end of 5 years for the final follow up examination. Success of ALT was defined as IOP

The trabecular meshwork in acute and chronic angle closure glaucoma.

PURPOSE: To determine the effect of acute and chronic primary angle closure glaucoma (PACG) on the trabecular meshwork. METHODS: Trabecular specimens of 16 consecutive patients with primary angle closure glaucoma (PACG)--6 acute PACG eyes, and 10 chronic PACG eyes without an acute attack--were studied by light and electron microscopy. RESULTS: Acute PACG: The trabecular meshwork revealed a generalised oedema and an accumulation of pigment in the widened trabecular spaces and Schlemm's canal. Attenuated trabecular endothelial cells appeared to be devoid of subcellular components. Chronic PACG: In chronic PACG eyes the trabecular architecture had lost its regular arrangement, with fewer and narrower trabecular spaces and fusion of the trabecular beams in areas. There were numerous electron-dense bodies in the trabecular tissues, both within the trabecular beams and in the extracellular spaces, which had a banded fibrillar structure. An overall loss of endothelial cells was noted; the remaining cells were crowded together and were polymorphic. Melanin pigment was present both within the stroma and in the endothelial cells. CONCLUSIONS: Pigment accumulation in the trabecular spaces and within the cells and a noninflammatory degeneration appeared to be the primary changes in the trabecular meshwork after acute angle closure glaucoma. In chronic PACG eyes, there was evidence of loss of endothelial cells and reactive repair processes. These changes were present in areas away from visible peripheral anterior synechiae. A gonioscopic evaluation of the extent of peripheral anterior synechiae alone may not reflect the extent of trabecular meshwork damage in acute and chronic PACG. Patients experiencing an acute attack of PACG require a long-term follow up, because the intraocular pressure (IOP) may rise later, due to ongoing changes compromising the outflow facility, or due to the effects of aging in the trabecular meshwork.

Assessing the role of subconjunctival versus intrascleral application of mitomycin C in high-risk trabeculectomies.

PURPOSE: To compare the efficacy and safety of subconjunctival and intrascleral applications of mitomycin C (MMC) in trabeculectomy for high-risk glaucomas. METHODOLOGY: A randomized prospective clinical study was conducted on 41 consecutive eyes with a high risk of glaucoma surgery failure. Patients were randomized to trabeculectomy and application of subconjunctival MMC or to trabeculectomy and application of intrascleral MMC. MMC solution 0.2 mg/ml was applied for 3 minutes under the conjunctival flap overlying the proposed site of trabeculectomy in Group I (n=21), or intrasclerally under the superficial scleral flap in Group II (n=20) RESULTS: After a follow-up of one year, the intraocular pressure (IOP) decreased from a mean basal IOP of 33.0 +/- 8.4 mm Hg to 12.56 +/- 2.54 mm Hg in Group I and from 30.9 +/- 6.6 mm Hg to 11.6 +/- 2.21 mm Hg in Group II. The IOP was 6-21 mmHg, without medication, in 90.5 % of the eyes in Group I and 75 % of the eyes Group II. Ocular hypotony, hypotony maculopathy, choroidal detachment and a shallow anterior chamber were more frequent with the intrascleral application of MMC during trabeculectomy, but the difference was not statistically significant. The overall success of the surgery at one year, i.e., achieving an IOP of 6-21 mmHg and a stable vision, (reduction in visual acuity of < or = 2 lines), was 90.5% in Group I and 75 % in Group II. CONCLUSION: No significant difference was seen in overall success or complication between subconjunctival and intrascleral application of MMC-augmented trabeculectomies in glaucomatous eyes at high risk of surgical failure.