Tarek A. Shazly

Neovascular Glaucoma: Etiology, Diagnosis and Prognosis

Neovascular glaucoma (NVG) is a severe form of glaucoma with devastating visual outcome attributed to new blood vessels obstructing aqueous humor outflow, usually secondary to widespread posterior segment ischemia. Invasion of the anterior chamber by a fibrovascular membrane initially obstructs aqueous outflow in an open-angle fashion and later contracts to produce secondary synechial angle-closure glaucoma. The full blown picture of NVG is characteristized by iris neovascularization, a closed anterior chamber angle, and extremely high intraocular pressure (IOP) with severe ocular pain and usually poor vision.

Long-term safety and efficacy of selective laser trabeculoplasty as primary therapy for the treatment of pseudoexfoliation glaucoma compared with primary open-angle glaucoma

Purpose To investigate the safety and efficacy of selective laser trabeculoplasty (SLT) to reduce intraocular pressure (IOP) in patients with pseudoexfoliation glaucoma (PXFG) compared with primary open-angle glaucoma (POAG). Design Non-randomized, prospective, clinical trial. Methods Nineteen eyes of 13 patients with POAG and 18 eyes of 13 patients with PXFG were treated with SLT. Patients were followed without antiglaucoma medications until additional medical, laser, or surgical intervention was initiated, at which time they were considered failures, had withdrawn from the study, or underwent a second SLT. Results The POAG and PXFG eyes showed similar reductions of IOP over the 49 months of follow-up. At 30 months of follow-up the POAG group showed a mean IOP of 17.6 ± 2.8 mmHg and a mean IOP reduction of 5.7 ± 2.1 mmHg; the PXFG group showed a mean IOP of 18.3 ± 4.7 and a mean IOP reduction of 5.3 ± 3.0 mmHg. Four eyes in the PXFG group and three eyes in the POAG group failed by 30 months. The cumulative probability of success was 74% for the PXFG group and 77% for the POAG group. Four PXFG eyes underwent a second SLT after 30 months of follow-up with a final IOP of 17.6 ± 2.8 mmHg. There were no serious adverse events. Conclusion SLT is a safe and effective method to lower IOP in patients with PXFG as initial glaucoma therapy. Both groups showed similar IOP reductions and failure rates.

Posner–Schlossman Glaucomatocyclitic Crisis

In 1948, Posner and Schlossman first reported glaucomatocyclitic crisis, an uncommon form of glaucoma characterized by recurrent unilateral episodes of markedly elevated intraocular pressure (IOP) with mild idiopathic anterior chamber inflammation. The exact etiology of glaucomatocyclitic crisis is not clear. Although it is typically a self-limited condition, some cases with advanced optic nerve cupping and associated visual field loss have been reported. Diagnosis of Posner-Schlossman syndrome is difficult, and it may mimic a variety of ocular disorders. Treatment of this syndrome is directed towards controlling the inflammation and associated IOP elevation.

Effect of prior cataract surgery on the long-term outcome of selective laser trabeculoplasty.

Objective: To determine if pseudophakia affects selective laser trabeculoplasty (SLT) intraocular pressure (IOP) lowering effect. Methods: A retrospective chart review was performed on 94 eyes of 75 consecutive patients who underwent SLT as primary treatment for ocular hypertension and primary open-angle glaucoma between 2002 and 2005 and completed at least 30 months follow up. Patients were excluded if they required additional glaucoma medications, laser, or ocular surgery during the follow-up period. Patients were categorized as phakics or pseudophakics. Independent-samples t-test was performed to compare the mean percentage of IOP reduction at 3, 6, 12, 18, and 30 months after SLT between the phakic and pseudophakic groups. Results: Seventy-six phakic and 18 pseudophakic eyes were included. IOP reduction in phakic group was 27.4% (2 week), 29.8% (3 months), 27.7% (9 months), 27.4% at (12 months) and 27.3% at (30 months). In pseudophakic patients, the mean IOP reduction was 19.8% (2 weeks), 26.5% (3 months), 23.2% (9 months), 22.5% (12 months), and 25.9% (30 months). An independent-sample t-test compared the percentage of IOP reduction between the phakic and pseudophakic groups and revealed higher percentage of IOP reduction in the phakic group at 2 weeks by 7.6% (P = 0.01). P value for difference was 0.34 (3 months), 0.25 (6 months), 0.18 (9 months), 0.12 (12 months), 0.36 (18 months), and 0.7 (30 months) after SLT. Conclusions: SLT response was delayed in pseudophakic compared to phakic patients, while the long-term effectiveness of SLT is the same in both groups.

Effect of Central Corneal Thickness on the Long-Term Outcome of Selective Laser Trabeculoplasty as Primary Treatment for Ocular Hypertension and Primary Open-Angle Glaucoma

Purpose: To determine if central corneal thickness (CCT) impacts the intraocular pressure (IOP)-lowering effect of selective laser trabeculoplasty (SLT) in patients with ocular hypertension (OHT) and primary open-angle glaucoma (POAG). Methods: A retrospective chart review of consecutive patients, who underwent SLT as primary treatment for OHT and POAG, between 2002 and 2005, was performed. Partial correlation analysis was performed to correlate the CCT to the percentage of IOP reduction at 3 to 30 months after SLT. Independent samples t test was performed to compare mean percentage of IOP reduction in eyes with CCT less than 555 &mgr;m versus CCT 555 &mgr;m or greater. Results: Eighty eyes of 47 patients were identified. The partial correlation coefficient value between the CCT and percentage of IOP reduction after SLT at 3 months was −0.253 (P = 0.025), at 12 months it was −0.22 (P = 0.049), and at 30 months it was 0.301 (P = 0.007). Independent samples t test showed that the mean percentage of IOP reduction in eyes with thinner corneas (CCT < 555 &mgr;m) was greater than that in thicker corneas (CCT ≥ 555 &mgr;m) at 3-, 6-, 9-, 12-, and 30-month post-SLT (P < 0.05). Conclusions: In patients with POAG and OHT, percentage of IOP reduction after SLT was significantly greater in eyes with thinner corneas (CCT < 555 &mgr;m). These findings indicate that patients treated with SLT as primary therapy who had thinner corneas demonstrated better IOP control for at least 30 months after SLT.

Prevalence of Pseudoexfoliation Syndrome and Pseudoexfoliation Glaucoma in Upper Egypt

BackgroundPseudoexfoliation (PXF) is a recognized risk factor for developing cataract, glaucoma and lens dislocation. PXF is also associated with increased risk of complications during cataract surgery due to poor mydriasis and zonular weakness. The aim of this study is to report the prevalence of pseudoexfoliation among Upper Egyptians attending the ophthalmology clinic of Assiut University Hospital.MethodologyA retrospective, chart review study conducted in the period from February 2002 to August 2009. A total of 7738 patients aged 40 years or older attending the general ophthalmic clinics were included in this study. A detailed evaluation including ophthalmic and general history, slit lamp biomicroscopy, intraocular pressure measurement, gonioscopy and dilated eye examination were performed. Patients with pseudoexfoliative material on the anterior lens surface and ⁄ or the pupillary margin in either or both eyes were labeled as having PXF.ResultsOut of the 7738 patients included, three hundred twenty (4.14%) subjects had PXF. Mean age of PXF group was 68.15 years (SD 8.16, range 40-92 years). PXF was bilateral in 82.2% of cases. It was significantly associated with cataract, glaucoma and hearing loss. Of the PXF patients, 65% had cataract, 30.3% had glaucoma and 8.1% had hearing loss.ConclusionPseudoexfoliation appears to be a common disorder in older individuals in Upper Egypt.

Pediatric ocular injuries from airsoft toy guns.

PURPOSE To report ocular injuries caused by airsoft guns in children. METHODS A retrospective chart review of pediatric patients who sustained ocular injuries related to airsoft guns between November 2005 and December 2007. Place of trauma, presenting symptoms and signs, surgical interventions performed, and final visual outcome were reviewed. RESULTS Thirty-two patients with a mean age of 8.8 ± 4.0 years (range: 1.5 to 18 years) were examined; 28 were boys (87.5%). Presenting visual acuity ranged from hand motions to 20/20 and could not be assessed in 2 patients. Hyphema was a common finding that was present in 24 cases, corneal abrasions were present in 10 cases, and raised intraocular pressure was present in 7 cases. Seven patients presented with traumatic cataract, and two had iridodialysis. Immediate surgical intervention was performed in 7 patients and 7 patients were scheduled for elective surgery. The patients presented after an average of 1.9 ± 1.9 days (range: 4 hours to 6 days) after the injury. Average follow-up was 18 days (range: 7 days to 5 months). Final visual acuity was 20/200 or worse in 5 patients, 20/40 or better in 23 patients, and could not be assessed in 2 cases. CONCLUSION Airsoft guns can cause a variety of serious injuries, sometimes necessitating operative intervention. The long-term morbidity from some of these injuries is significant. Airsoft guns are capable of inflicting serious and permanent ocular damage.

Autoimmune Basis of Glaucoma

Glaucoma is one of the leading causes of blindness worldwide. The current view of glaucoma is that it is a multifactorial disease. Elevated IOP is a recognized etiologic factor which can trigger initial damage through biomechanical and ischemic injury to the retinal ganglion cells. However, elevated intraocular pressure cannot be entirely responsible for the development of glaucoma. Accumulating evidence suggests that abnormal immunity may be contributing to the glaucomatous optic neuropathy. Autoimmunity may be responsible for initiating or exacerbating glaucoma. This review provides an evaluation of the potential role of autoimmunity in some patients with glaucoma.

Comparison of Intraocular Pressure-Lowering Effect of Every Night Versus Every Other Night Dosing of Bimatoprost 0.03%

PURPOSE To compare intraocular pressure (IOP) reduction profiles of bimatoprost 0.03% administered every other night (QOD-HS) compared with every night (QHS) in patients with primary open angle glaucoma and pseudoexfoliation glaucoma. METHODS A retrospective chart review of 68 eyes of 45 consecutive patients who were switched from QHS to QOD-HS bimatoprost due to intolerable conjunctival hyperemia between May 2005 and May 2008. IOP in the morning (AM) and afternoon (PM) of the next day after administration (day 1) and the day after (day 2) on QOD-HS regimen was compared with IOP in the AM and PM when they were on QHS regimen, 4-6 weeks after switching to QOD-HS. RESULTS Mean IOPs on QHS bimatoprost were 15.9±3.4 mm Hg in the AM and 15.5±2.7 mm Hg in the PM, whereas mean IOPs on QOD-HS were 14±2 mm Hg (AM) and 14.2±2.5 mm Hg (PM) on day 1, and 14.7±2.6 mm Hg (AM) and 14.4±2.4 mm Hg (PM) on day 2 after administration. Differences between IOP fluctuation on QHS and QOD-HS days 1 and 2, respectively, were not significant (P=0.87 and 0.94). CONCLUSION Every other night dosing of bimatoprost was effective in controlling IOP in this select group of patients with primary open angle glaucoma and pseudoexfoliation glaucoma who had troublesome side effects on bimatoprost 0.03% QHS regimen, and may be considered as an alternative to every day treatment.

Intraoperative Optical Coherence Tomography-assisted Descemet Stripping Automated Endothelial Keratoplasty for Anterior Chamber Fibrous Ingrowth

Purpose: Here, we present the first reported case of intraoperative optical coherence tomography (OCT)-assisted Descemet membrane stripping automated endothelial keratoplasty (DSAEK) in a patient with anterior segment fibrous ingrowth. Methods: A 61-year-old woman with corneal edema and chronic angle-closure glaucoma secondary to fibrous ingrowth after 2 glaucoma shunt device implantations underwent dissection and removal of anterior chamber fibrous ingrowth and DSAEK. The surgical techniques using intraoperative OCT and outcome are described. Results: Intraoperative OCT provided a clear dissection plane of the fibrous membranes in the anterior chamber and view of their relation to the iris and corneal endothelium, despite an opacified cornea. The placement of the donor lenticule and absence of interface fluid were also verified intraoperatively. The postoperative course was uncomplicated with satisfactory outcome. Conclusions: We conclude that intraoperative OCT is a useful tool during DSAEK surgery, particularly in complicated cases such as anterior segment fibrous ingrowth and significant corneal edema.