Long-Term Outcomes of Trabeculectomy in Korean Patients with Juvenile Open-Angle Glaucoma

PURPOSE: To evaluate the outcomes and prognostic factors of trabeculectomy with mitomycin C in Korean patients with juvenile open-angle glaucoma (JOAG). METHODS: A retrospective review was performed on 29 eyes with JOAG who had undergone trabeculectomy between January 2004 and January 2013. Intraocular pressure (IOP) and postoperative complications were monitored at 1 day preoperatively, at 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months postoperatively, and at final follow-up after postoperative 18 months. Surgical success was defined as a final IOP of <21 mm Hg or <80% of preoperative IOP, regardless of the use of anti-glaucoma medication. Prognostic factors for surgical success or failure were analyzed by the Cox proportional hazards model. RESULTS: Mean (+/- standard deviation) age at trabeculectomy was 24.6 (+/- 8.9) years, and mean follow-up period was 24.3 (+/- 20.8) months. The overall success rate was 82.8% at final follow-up. The Kaplan-Meier cumulative probabilities of surgical success were 100% at 1 year, 87.4% at 2 years, and 78.7% at 3 years postoperatively. The Cox proportional hazards model failed to determine any significant factors that were associated with surgical failure. The three most frequent postoperative complications were immediately postoperative hypotony (n = 19, 65.5%), hypotony maculopathy (n = 8, 27.6%), and encapsulated bleb (n = 8, 27.6%), most of which were resolved after a minor procedure or observation. Two of 8 eyes with encapsulated bleb required a second surgery. There were no vision-threatening severe complications. CONCLUSIONS: Trabeculectomy with MMC may be an effective treatment in Korean JOAG patients.

Leber's Hereditary Optic Neuropathy in a Patient Diagnosed With Normal Tension Glaucoma: A Case Report

PURPOSE: Leber's hereditary optic neuropathy (LHON) is caused by point mutations in mitochondrial DNA. The authors report a case of a middle-aged man with genetically confirmed LHON, combined with bilateral normal tension glaucoma (NTG). CASE SUMMARY: A 48-year-old man presented with complaints of decreased visual acuity in his left eye. His corrected visual acuity was 20/16 in the right eye and 20/63 in the left eye. The fundus photographs revealed a bilateral, superotemporal and inferotemporal retinal nerve fiber layer defect, corresponding to his visual field defect. The patient was diagnosed with bilateral NTG. After 2 months, the patient's corrected visual acuity in the left eye worsened to counting fingers and a central visual field defect was noticed in the Humphrey visual field test in the left eye. At 4 months after the initial visit, his corrected visual acuity in the right eye became 20/100, and the Goldmann visual field test demonstrated cecocentral scotoma. The fundus photographs showed a papillomacular bundle defect in his left eye. At 7 months after the initial visit, his visual acuity was hand movement in the right eye and a finger count in the left eye. A series of LHON gene mutation tests revealed a 11778 mitochondrial gene mutation, and the patient was diagnosed with LHON. CONCLUSIONS: Proper diagnosis of LHON might be disturbed by atypical manifestation of other optic nerve diseases, such as glaucoma. Therefore, suspecting LHON and checking for gene mutations as part of the work-up in patients with bilateral optic neuropathy is critical.

The Measurement of Flow Resistance in Drainage Implants Using Various Tube Ligation Methods

PURPOSE: To evaluate the flow resistance though the tube in a glaucoma drainage implant using various tube ligation methods. METHODS: To measure the flow resistance, the following tube ligation methods were designed and tested: Type 1: no ligation of Ahmed valve tube. Type 2: ligation of Ahmed valve tube with 8-0 Vicryl. Type 3: ligation of Molteno tube and a 6-0 Vicryl as an intra-luminal stent with 8-0 Vicryl. Type 4: ligation of Ahmed valve tube and three strands of 8-0 nylon as extra-luminal stents with 8-0 Vicryl. Type 5: ligation of Ahmed valve tube and a 6-0 Prolene as an extra-luminal stent with 8-0 Vicryl followed by removal of the Prolene for partial ligation. RESULTS: The pressure was maintained under 0.143 mm Hg in type 1. In type 2, the pressure increased to 6.688 mm Hg and dropped to approximately 6.384 mm Hg. In type 3, the pressure was maintained at 5.396 mm Hg which decreased to 3.572 mm Hg after stent removal. In type 4, the pressure was maintained at 5.700 mm Hg which dropped to 5.472 mm Hg after the 1st stent removal, to 5.016 mm Hg after the 2nd stent removal and to 4.180 mm Hg after the 3rd stent removal. In type 5, the pressure increased to 6.384 mm Hg and decreased to 5.624 mm Hg. CONCLUSIONS: The tube ligation along with extra-luminal stents followed by staged removal may provide prevention of hypotony and staged control of intraocular pressure after a glaucoma implant operation.

Change in Angle Parameters Measured by Anterior Segment Optical Coherence Tomography after Laser Peripheral Iridotomy Alone versus Laser Peripheral Iridotomy and Argon Laser Peripheral Iridoplasty

PURPOSE: To compare the changes in angle parameters after laser peripheral iridotomy (LPI) alone versus LPI and ALPI (argon laser peripheral iridoplasty) in primary angle closure patients by using anterior segment optical coherence tomography (AS-OCT). METHODS: A total of 25 eyes from 17 patients with narrow angles were enrolled in this present study. Eleven eyes in the LPI treatment group and 14 eyes in the LPI and ALPI combined treatment group were evaluated using AS-OCT. The anterior chamber depth (ACD), angle opening distance at 500 microm (AOD 500) and 750 microm (AOD 750), angle recess area at 500 microm (ARA 500) and 750 microm (ARA 750), trabecular-iris space area at 500 microm (TISA 500) and 750 microm (TISA 750), trabecular-iris angle (TIA) were measured. The pre- and post-treatment parameters were compared in each group. The parameter changes after laser treatment were also compared. RESULTS: AOD 500, AOD 750, ARA 500, ARA 750, TISA 500 and TISA 750 except ACD significantly increased following LPI treatment (p = 0.013, p = 0.010, p = 0.008, p = 0.003, p = 0.006, p = 0.003, p = 0.013, respectively, Wilcoxon signed rank test) and LPI and ALPI combined therapy (p = 0.001, p = 0.001, p = 0.001, p = 0.001, p = 0.001, p = 0.001, p = 0.001, respectively, Wilcoxon signed rank test). The AOD 500 difference, TISA 500 difference, and TISA 750 difference were significantly greater after LPI and ALPI combined therapy than after LPI treatment alone (p = 0.112, p = 0.147, p = 0.049, p = 0.037, respectively, Mann-Whitney U-test). CONCLUSIONS: The results from the present study showed LPI alone or LPI and ALPI combined therapy significantly widened the anterior chamber angle and combined therapy showed greater effect than LPI alone.

The Clinical Usefulness of the Hong's Grading Method

PURPOSE: To compare the Hong's grading method, utilized for slit-lamp grading of the mid-peripheral angle, with other conventional grading methods. Actual angle was measured by ultrasound biomicroscopy (UBM) for comparison. METHODS: Fifteen eyes with narrow angles and eighteen eyes with wide angles were studied. The average age of thirty-three subjects was 46.8+/-19.2, and the male to female ratio was 1:3.7. The mid-peripheral angle was graded by Hong's, van Herick's and Spaeth's grading system. The actual anterior chamber angle was evaluated by UBM and the correlation between each grading system and actual angle was investigated. RESULTS: The results from the Hong's grading (r=0.802, R2=0.643, p<0.01), Spaeth's grading (r=0.728, R2=0.530, p<0.01) and van Herick's grading (r=0.618, R2=0.382, p<0.01) methods correlated significantly with the actual angles. CONCLUSIONS: The Hong's grading method was an easy and effective tool to evaluate anterior chamber angle. In addition, the results of the Hong's grading method were closer to the actual angle than the other methods.