Comparison of the Outcome of Silicone Ahmed Glaucoma Valve Implantation with a Surface Area between 96 and 184 mm2 in Adult Eyes

PURPOSE: To compare the success rates, complications, and visual outcomes between silicone Ahmed glaucoma valve (AGV) implantation with 96 mm2 (FP8) or 184 mm2 (FP7) surface areas. METHODS: This study is a retrospective review of the records from 132 adult patients (134 eyes) that underwent silicone AGV implant surgery. Among them, the outcomes of 24 eyes from 24 patients with refractory glaucoma who underwent FP8 AGV implantation were compared with 76 eyes from 76 patients who underwent FP7 AGV implantation. Preoperative and postoperative data, including intraocular pressure (IOP), visual acuity, number of medications, and complications were compared between the 2 groups. RESULTS: There were no significant differences in baseline characteristics between the 2 groups (p > 0.05). The postoperative visual acuity of the patients in the FP8 group was better than that of the patients in the FP7 group in some early postoperative periods (p 0.05). Postoperative IOP was not significantly different between the 2 groups (p > 0.05) except for IOP on postoperative day 1 (11.42 mmHg for the FP7 group and 7.42 mmHg for the FP8 group; p = 0.031). There was no statistical difference in success rates, final IOP, number of medications, or complication rates between the 2 groups (p > 0.05). CONCLUSIONS: The FP7 and FP8 AGV implants showed no difference in terms of vision preservation, IOP reduction, and number of glaucoma medications required.

Comparison of 180degrees and 360degrees Selective Laser Trabeculoplasty

PURPOSE: To compare the effect and safety of two regimens of Selective Laser Trabeculoplasty (SLT), SLT on 180degrees of trabecular meshwork and SLT with 100 laser spots on 360degrees of trabecular meshwork in patients with primary open-angle glaucoma and ocular hypertension. METHODS: In a retrospective clinical study, the authors compared the pressure-lowering effects of SLT in two groups of patients; group 1 (83 patients) received SLT on 180degrees, group 2 (30 patients) on 360degrees of trabecular meshwork. The clinical outcome indicators included intraocular pressure (IOP) at one day, one week, one month, two months, three months and six months after SLT, and the anterior chamber reaction at post-laser one day. RESULTS: There was no statistically significant difference in the IOP reduction between these two regimens after six months. The anterior chamber reactions in the two groups were significantly different (group 1; 0.61 +/- 0.64, group 2; 1.25 +/- 0.83, p = 0.001). The success rate of group 2 (43.3%) was not different from that of group 1 (31.3%; p = 0.23). CONCLUSIONS: SLT on 180degrees of trabecular meshwork had a similar effect compared to that of SLT on 360degrees of trabecular meshwork in terms of IOP reduction. The authors of the present study suggest that 180degrees SLT is the safest procedure with regard to success rate and complications.

Surgical Treatment of Overhanging Bleb Using Indocyanin Green Dye

PURPOSE: To report a case of overhanging bleb excision using Indocyanin green (ICG) dye. CASE SUMMARY: A 71-year-old man visited our clinic complaining of a white corneal foreign body in his left eye. The patient underwent mitomycin-assisted trabeculectomy surgery 8 years prior. Slit lamp examination revealed a large overhanging bleb. Because of its large size, surgical excision using ICG dye was performed. After excision surgery, the IOP was well controlled and no anterior chamber inflammation was observed. Two months later, the IOP was still stable at 11 mm Hg and no recurrence of the overhanging bleb was found. CONCLUSIONS: ICG dye is useful in delineating between a functioning bleb and a non-functioning overhanging bleb. ICG dye-assisted bleb excision is a useful method for decreasing complications such as aqueous humor leakage and damage of the original bleb.

Quantitative Analysis of Optic Disc Color

PURPOSE: To evaluate the reproducibility of ImageJ software in analyzing the color of the optic disc. METHODS: One hundred twelve normal participants (56 males and 56 females) were enrolled in this study. The image of the optic disc was taken using Kowa digital disc photo-graphy, and the gray scales of the nasal rim (NR), brightest cupping center (BCC) and largest inferior retinal vein (IRV) were calculated using histogram in ImageJ. Three different observers calculated the gray scales three separate times. Reproducibility was assessed using the interclass correlation coefficient (ICC). RESULTS: The mean age of the participants was 50.6 years old (range, 11 to 82 years). The mean gray scales of the nasal rim were 91.81, 94.91, and 93.24; those of the brightest cupping center were 174.84, 179.94, and 177.76; and those of the largest inferior retinal vein were 61.85, 53.48, and 56.73 for observers 1, 2, and 3, respectively. Inter-observer reproducibility for NR, BCC and IRV was considered good based upon ICC values of 0.944, 0.860, and 0.789 for observers 1, 2, and 3, respectively. Significant age-related differences between the values of the brightest cupping center were noted, and the gray scale score was decreased in the older participants (p < 0.001). CONCLUSIONS: The gray scale of the brightest cupping center diminished with age. ImageJ can be a useful objective tool with high reproducibility in the analysis of optic disc color.

Comparison of Outcome of Trabeculectomy With Mitomycin C and Ahmed Valve Implantation for Uveitic Glaucoma

PURPOSE: To assess and compare the clinical outcomes of primary trabeculectomy with mitomycin C and Ahmed valve implantation for secondary open-angle glaucoma following uveitis. METHODS: This study was conducted retrospectively on 30 eyes of 25 patients with open-angle glaucoma secondary to uveitis that had undergone trabeculectomy with mitomycin C and 33 eyes of 24 patients that had undergone Ahmed valve implantation. The clinical outcome indicators used in this study were intraocular pressure (IOP), number of anti-glaucoma agents, surgical success rate and occurrence of complications. RESULTS: Mean IOP and surgical success rate in patients who had undergone trabeculectomy with mitomycin C after a 12 month postoperative period were 14.0+/-8.2 mmHg and 76.7%, respectively, while those of patients with Ahmed valve implantation were 13.2+/-7.7 mmHg and 81.8%. The data did not show clinical significance. There was greater risk of surgical failure in patients at a younger age and/or with diabetes mellitus in cases of having gone through trabeculectomy with mitomycin C. CONCLUSIONS: Both trabeculectomy with mitomycon C and Ahmed valve implantation can be considered as primary surgical treatments for patients with open-angle glaucoma secondary to uveitis. However, trabeculectomy with mitomycin C should only be applied to a limited extent in patients that are young and/or have diabetes mellitus.

Concentration of Vascular Endothelial Growth Factor After Intracameral Bevacizumab Injection in Eyes With Neovascular Glaucoma

PURPOSE: To study the concentration of vascular endothelial growth factor (VEGF) in the aqueous humor before and after intracameral injection of bevacizumab in eyes with neovascular glaucoma, and to detect the duration of an anti-VEGF effect of bevacizumab in the anterior chamber. METHODS: In this prospective interventional case series, 1.25 mg of bevacizumab was injected into the anterior chamber of five eyes in five neovascular glaucoma patients. Aqueous humor samples were obtained just before intracameral injection of bevacizumab and two weeks after injection. The concentrations of VEGF in the aqueous humor were measured using ELISA. To investigate corneal endothelial damage after intrecameral bevacizumab injection, specular microscopy was performed before injection and two weeks after injection. Slit lamp photo and iris fluorescent angiography was performed to determine the regression of iris neovascularization. RESULTS: After injection, substantial regression of neovascularization or fluorescein leakage was seen in all treated eyes. The VEGF concentrations in the aqueous humor in eyes with NVG were 1181.8+/-1248.3 pg/mL before intracameral injection of bevacizumab. Two weeks after injection, the VEGF concentrations decreased to 33.2+/-12.2 pg/mL (p=0.04, Wilcoxon signed rank test). There were no significant changes in IOP or corneal endothelial cells. CONCLUSIONS: Intracameral bevacizumab injection can remarkably reduce iris neovascularization in neovascular glaucoma patients. VEGF levels were significantly decreased two weeks after injection and corneal toxicity was not observed during short term follow-up.

Delayed Suprachoroidal Hemorrhage After Ahmed Valve Implantation for Neovascular Glaucoma

PURPOSE: To report the case of delayed suprachoroidal hemorrhage after Ahmed valve implantation in a neovascular glaucoma (NVG) patient. CASE SUMMARY: A 74-years-old male visited the hospital with ocular pain in the left eye. He had a history of vitrectomy and Intraocular lens (IOL) scleral fixation due to trauma in the left eye. NVG was diagnosed and Ahmed valve was implanted in his left eye. Three days later, hypotony occurred with all quadrant choroidal detachment. Next day, raised intraocular pressure (IOP) was checked and anterior chamber was flat on slit lamp examination. Vitreous hemorrhage and suprachoroidal hemorrhage were suspected. We performed anterior chamber formation with viscoelastics. The anterior chamber became deeper and hemorrhage gradually decreased. A month later, the patient visited us with severe ocular pain. Raised IOP and shallow anterior chamber due to moderate hyphema and anteriorly placed IOL were found. Retinal detachment was suspected on B-scan. Vitrectomy, IOL removal, silicone oil insertion, and Ahmed valve removal were performed. CONCLUSIONS: We report we experienced one patient of delayed suprachoroidal hemorrhage after Ahmed valve implantation and he had poor prognosis.

Comparison of Safety and Efficacy Between Silicone and Polypropylene Ahmed Glaucoma Valves

PURPOSE: To compare the safety and efficacy of polypropylene and silicone Ahmed glaucoma valves (AGVs). METHODS: The medical records of 62 consecutive refractory glaucoma patients who had undergone AGV implantion from March 2003 to December 2005 were reviewed retrospectively. Among the 62 patients, 32 patients underwent polypropylene AGV implantation (group P) and the other 30 patients underwent silicone AGV implantation (group S). Postoperative IOP, the complication rate, and the success rate were compared between the two groups. RESULTS: The life-table success rates for the group P were 81.3% at 6 months and 71.2% at 12 months, and the success rates for the group S were 89.9% at 6 months and 78.6% at 12 months, showing no significant difference between the two groups. Complications, including non-tube-related complications, were observed more frequently in the group S, but there was no significant difference between the two groups. CONCLUSIONS: The silicone AGV can reduce IOP effectively but may be associated with non-tube-related complications.

Transforming Growth Factor-beta Levels in Human Aqueous Humor of Glaucomatous, Diabetic and Uveitic Eyes

PURPOSE: Transforming growth factor-beta2 is known to be present at elevated levels in the aqueous humor of patients with primary open angle glaucoma (POAG) and diabetes but not in uveitis-related secondary glaucoma. We investigated total TGF-beta2 levels and levels of the active form of TGF-beta2 in the aqueous humor of eyes with different types of glaucoma. METHODS: The concentration of the total and active form of TGF-beta2 was measured in 63 patients with primary open angle glaucoma, neovascular glaucoma complicated with diabetes (NVG), and secondary open angle glaucoma complicated with uveitis (SOAG) using a double antibody 'sandwich-indirect' ELISA method. RESULTS: The levels of total TGF-beta2 in the aqueous samples of POAG, NVG, and SOAG were elevated. The levels of active TGF-beta2 in the aqueous samples of POAG, and NVG were also elevated, whereas the level of active TGF-beta2 was within the normal range in the aqueous samples of SOAG. CONCLUSIONS: These results suggest that the level of TGF-beta2 may play a role in the pathology of various types of glaucoma.

The Comparison of Intraocular Pressure Elevation after Intravitreal Injection of Different Concentration of Triamcinolone Acetonide

PURPOSE: The purpose of this study was to compare the effects of intravitreal injections of 4 mg or 8 mg triamcinolone acetonide(TA) on intraocular pressure (IOP) in macular edema. METHODS: This was a retrospective study conducted by reviewing follow-up records for the eyes of 60 patients with macular edema 6 months receiving a intravitreal TA injection. Two groups, A and B, who had received TA injections of either 4 or 8 mg, respectively, were compared. RESULTS: The average pre-injection IOP for group A was 12.8+/-2.6 mmHg, and the average post-injection IOP at 1 day, 1 week, 1 month, 3 months, and 6 months was 15.0+/-2.7, 14.6+/-3.2, 15.3+/-3.5, 15.8+/-4.0, and 14.4+/-2.8 mmHg, respectively. The average pre-injection IOP for group B was 12.5+/-2.4 mmHg, and the average post-injection IOP at 1 day, 1 week, 1 month, 3 months, and 6 months was 14.9+/-2.9, 14.3+/-3.0, 14.7+/-3.2, 15.2+/-4.4, and 14.5+/-4.5 mmHg, respectively. The difference in IOP elevation between the two groups was not statistically significant (p>0.05). CONCLUSIONS: There was no statistically significant difference between a 4 mg or 8 mg intravitreal TA injection with respect to IOP elevation.

Changes in Axial Length Following Trabeculectomy and Ahmed Glaucoma Valve Implantation

PURPOSE: This study examines the changes in axial length after trabeculectomy and Ahmed glaucoma valve implantation surgery. METHODS: In the forty three eyes of the 42 patients who had the uncontrolled glaucoma, 22 eyes of 21 patients having trabeculectomy and 21 eyes of 21 patients having Ahmed glaucoma valve implantation from October 2004 to September 2005 at Kim's Eye Hospital were analyzed prospectively. These patients had IOP and axial length measurements preoperatively, at 1 week, 1 month, and 3 months after surgery and refractive power measurements preoperatively, at 3 months after surgery. Axial length was measured by IOL Master(R). RESULTS: There was a statistically significant reduction in IOP after 3 months of 26.6+/-11.2 mmHg overall, 22.4+/-8.4 mmHg following trabeculectomy, and 30.9+/-12.3 mmHg after Ahmed glaucoma valve implatation (p<0.001). There was a statistically significant reduction in axial length after 3 months of -0.24+/-0.10 mm overall, -0.21+/-0.1 mm after trabeculectomy and -0.28+/-0.1 mm after Ahmed glaucoma valve implantation. CONCLUSIONS: There was a statistically significant decrease in axial length after both trabeculectomy and Ahmed glaucoma valve implantation. We must consider the influence of axial length change on refraction in planning combined glaucoma and cataract surgery or future IOL implantation.

Neovascular Glaucoma: Diode Laser Trans-Scleral Cyclophotocoaculation Versus Ahmed Glaucoma Valve Implant

PURPOSE: To retrospectively study the clinical outcomes of diode laser trans-scleral cyclophotocoagulation and Ahmed glaucoma valve implant in eyes with neovascular glaucoma. METHODS: We reviewed the medical records of patients who had undergone diode laser trans-scleral cyclophotocoagulation (group 1) and Ahmed glaucoma valve implant (group 2) with a follow-up period of 6 months or longer. The treatments were carried out to control high intraocular pressure (IOP) and ocular pain in the patients with visual acuity less than hand motions. RESULTS: Group 2 had a significantly lower IOP during the first postoperative month. The cumulative probability of success was higher in group 2 than group 1 throughout the follow-up period. The postoperative complications in most cases were transient and improved with conservative management in both groups. However, 3 cases in group 1 required evisceration secondary to phthisis. Subjective relief of ocular pain was higher in group 2. CONCLUSIONS: The Ahmed glaucoma valve implant group showed a higher success rate and fewer serious complications than the diode laser trans-scleral cyclophotocoagulation group in patients with high IOP and ocular pain with poor visual acuity. Diode laser trans-scleral cyclophotocoagulation may be considered in patients with poor general health.

Ahmed Valve Implantation Using Scleral Tunneling

PURPOSE: To assess the usefulness of Ahmed valve implantation using scleral tunneling. METHODS: Thirty-four eyes of 34 patients with refractory glaucoma who had not responded to medical treatment nor previous glaucoma surgery was given Ahmed valve implantation using scleral tunneling and were enrolled in the study with a minimum follow-up of six months. RESULTS: The mean follow-up period was 7.7 +/- 2.8 months (6~24 months). The mean preoperative IOP was 47.6 +/- 6.9 (25~70) mmHg and the mean postoperative IOP at six months was 18.7 +/- 9.8 (4~31) mmHg. The postoperative success rate was 73.5% and 73.3% at six and eighteen months, respectively, and was not affected by sex, preoperative diagnosis, or preoperative IOP. The postoperative complications were hyphema (4 eyes), choroidal detachment (3 eyes), and immediate hypotony (3 eyes). CONCLUSIONS: Ahmed valve implantation using scleral tunneling is useful, especially when patch graft is not available. The success rate was comparable with other traditional methods such as patch graft and scleral flap.

Clinical Evaluation of Recurrence Rate of Pterygium Operation according to Mitomycin C Concentration

PURPOSE: The authors compared the recurrence rate and complications of primary pterygium operation with respect to mitomycin C concentration. METHODS: Four hundred twenty three eyes with primary pterygium underwent surgery using the bared sclera method. One hundred nineteen eyes randomly chosen were treated with 0.02% mitomycin C (Group I) twice a day for 5days, 138 eyes were treated with 0.01% mitomycin C (Group II), and 166 eyes were treated with 0.005% mitomycin C (Group III). RESULTS: During the mean follow-up period of 6 months, the overall recurrence rate was 14.7% (62 eyes). Recurrence rates in each group : 8.4% (10 eyes) in Group I , 13.7% (19 eyes) in Group II , and 19.9% (33eyes) in Group III . Complications seen in Group I were corneal abrasion (1 eye), symblepharon (1 eye), and postoperative corneal scar (1 eye). Complications seen in Group II were symblepharon (1 eye), and postoperative corneal opacity (2 eye) and seen in Group III were symblepharon (1 eye), and postoperative corneal opacity (1 eye). We conclude that a higher concentration of mitomycin C (0.2 mg/ml) reduces the recurrence rate of pterygium. CONCLUSIONS: We recommend the use of mitomycin C concentration of 0.02% twice a day for 5days to lower the recurrence rate and complications after excision of primary pterygium

A Case of Phthiriasis Palpebrarum in Children

The majority of the crab louse is found in pubic hairs, but some of them will colonize axillary hairs, eyelashes, eyebrows and occasionally scalp hairs. In children crab louse may colonize the eyelashes and scalp hairs. The authors found a crab louse, Phthirus pubis and their nits on the eyelashes and scalp hiars of 25-months-old female who complained of foreign body and itching sensation of her right upper lid. Treatment is accomplished by careful mechanical removal of the louse and nits followed by the epilation and application of antibiotic eyedrops or ointments. We report a case of Phthiriasis palpebrarum in children.

Laser Suture Lysis after Trabeculectomy

We studied the efficacy of laser suture lysis in the promotion of filtration and bleb formation during the early postoperative period after trabeculectomy. Laser suture lysis was performed on thirty-two eyes of thirty patients considered overtight scleral flap suture among patients who underwent trabeculectomy with mitomycin-C, using an argon laser and a Hoskins lens. Patients were entered into the study if, after ocular massage, the intraocular pressure(IOP) was greater than our target pressure(8-12mmHg) 48 Hours after surgery, deep quiet anterior chamber, weak or no bleb formation, no bleb leakage, and a patent internal ostium on gonioscopy. Intraocular pressure measured within 5 minutes of lysis and gentle ocular massage was employed if there was no sopontaneous bleb formation. A further suture was lysed if at this stage there was still no bleb associated with a high IOP. Suture lysis was successful in all cases in the early postoperativy period. The mean IOP before lysis was 22.1mmHg and after serial lysis 9.8mmHg. Complications were noted with laser suture lysis: shallowing of anterior chamber, ocular hypotony, sunconjunctival hemorrhage, hyphema and cataract. All resolved with appropriate management. Laser suture lysis is a safe, effective, and non-invasive method, It can avoid surgical manipulation and increase long term success rate of trabeculectomy.

The Clinical Evaluation of Pars Plana Vitrectomy in various Ocular Disease

We reviewed the hospital records of 104 consecutive eyes in 101 patients who underwent pars plana vitrectomy at Presbyterian Medical Center from January 1993 to December 1995 and studied the postoperative visual acuity and postoperative complications. Possible indications for pars plana vitrectomy were follows: complications of proliferative diabetic retinopathy (30.7%),complications of other types of proliferative retinopathy except proliferative diabetic retinopathy(25.0%),complications of anterior segment surgeries (14.4%), complex retinal detachments(8.7%), intraocular inflammations and uveitis (8.7%), macular diseases (6.7%), and complications of ocular trauma (5.8%), Regarding postoperative final visual acuity, 53 eyes(51.0%) were improved, 30eyes(28.8%) were stabilized, 21eyes(20.2%) were worsened. Intraoperative or postopertive cataract, retinal breaks or retinal detachment were most frequent complications. We expected that pars plana vitrectomy might be indicated in various ocular diseases containing proliferative diabetic retinopathy.