Paul A. Sidoti

Intermediate-term Results of a Randomized Clinical Trial of the 350- versus- the 500-mm2 Baerveldt Implant

BACKGROUND The Baerveldt glaucoma implant is a large equatorial aqueous shunting device that is installed through a single-quadrant conjunctival incision. The intermediate-term results of a randomized study comparing the 350- and 500-mm2 Baerveldt implants are reported. METHODS Seventy-three patients with medically uncontrollable, nonneovascular glaucomas associated with aphakia, pseudophakia, or failed filters were enrolled in a randomized, prospective study comparing 350- and 500-mm2 Baerveldt implants. Surgical success was defined as 6 mmHg < or = final intraocular pressure < or = 21 mmHg without glaucoma reoperation or devastating complication. RESULTS Of patients with 350- and 500-mm2 implants, 93% and 88%, respectively, achieved surgical success (18-month life-table analysis, P = 0.93). The 500-mm2 implants afforded intraocular pressure control with significantly fewer medications (0.7 versus 1.3; P = 0.006). The postoperative visual acuities remained within one line of the preoperative visual acuities or improved in 62% and 66% of patients in the 350- and 500-mm2 groups, respectively (P = 0.93). Complication rates were statistically similar. The most frequent ones in the 350- and 500-mm2 groups, respectively, were serous choroidal effusion (16% and 32%), strabismus (16% and 19%), anterior uveitis (14% and 11%), and corneal or corneal graft edema (11% each). CONCLUSION The intermediate-term results of the 350- and 500-mm2 Baerveldt implants were statistically comparable with respect to surgical and visual outcomes, as well as complications, although the larger implant was associated with a higher rate of some complications. However, the 500-mm2 Baerveldt implant afforded intraocular pressure control with fewer medications than the 350-mm2 implant.

Experience with the Baerveldt Glaucoma Implant in Treating Neovascular Glaucoma

PURPOSE The authors present a retrospective study designed to assess the effectiveness of the Baerveldt glaucoma implant in controlling intraocular pressure (IOP) and maintaining visual function in eyes with neovascular glaucoma. METHODS The medical records of all 36 patients (36 eyes) who underwent Baerveldt glaucoma implantation for medically uncontrolled neovascular glaucoma between February 1991 and December 1992 were reviewed. RESULTS Eighteen patients received Model 350 implants, 16 received Model 500 implants, and 2 received Model 200 implants. The 12- and 18-month life-table success rates (success defined as 6 mmHg < or = final IOP < or = 21 mmHg without additional glaucoma surgery or devastating complication) were 79% and 56%, respectively. Visual acuity remained stable or improved in 10 (31%) patients. Postoperative complications included flat anterior chamber, serous choroidal detachment, and obstruction of the proximal tube tip with fibrovascular tissue, each of which occurred in four (11%) patients. Eleven (31%) patients lost light perception. There were no significant differences between the groups receiving the Model 350 and Model 500 implants with respect to life-table success rates, percentage of postoperative IOP reduction, or complication rates. Patients in the Model 500 implant group required significantly fewer antiglaucoma medications post-operatively, but also demonstrated a significantly greater mean visual acuity reduction. Better preoperative visual acuity and increased patient age were positively correlated with a successful outcome. CONCLUSIONS Baerveldt implantation is effective in controlling IOP elevation associated with neovascular glaucoma. Postoperative visual loss, despite adequate IOP control, is common. Young patient age and poorer preoperative visual acuity are significant predictors of surgical failure.

Bleb-related ocular infection in children after trabeculectomy with mitomycin C

OBJECTIVE The purpose of the study is to report the clinical course of bleb-related ocular infection in children after trabeculectomy with adjunctive mitomycin C. DESIGN The study design was a retrospective review of all patients with a diagnosis of bleb-related ocular infection after trabeculectomy with adjunctive mitomycin C. PARTICIPANTS Three children were identified in whom late postoperative bleb-related ocular infection developed. INTERVENTION Treatment consisted of vitreous biopsy with intravitreous antibiotic and corticosteroid injection and/or bleb culture with topical and intravenous antibiotic administration. MAIN OUTCOME MEASURES Visual acuity and intraocular pressure were measured. RESULTS Bleb-related ocular infection developed an average of 16.7 +/- 10.9 months after trabeculectomy (range, 4-23 months). The mean age at presentation was 7.0 +/- 2.6 years (range, 4-10 years). Vitreous cultures were positive for staphylococci in two cases. A bleb culture from the third case also grew staphylococcus. All of the children recovered their initial vision after treatment of infection. However, one lost six lines of vision after a subsequent retinal detachment. Additional glaucoma surgery was required in one patient. CONCLUSIONS Late bleb-related ocular infection may occur in children after trabeculectomy with mitomycin C and is characterized by abrupt onset, bleb infiltration, and rapid progression. Despite early preservation of vision after treatment of infection, significant late visual loss can occur.

Pericardial patch grafts in glaucoma implant surgery.

Purpose: The authors determine the safety and effectiveness of pericardial patch grafts in glaucoma implant surgery.Methods: A retrospective chart review was conducted on all patients who underwent a glaucoma implant procedure with the use of a pericardial patch graft to cover the subconjunctival portion of the tube at The New York Eye and Ear Infirmary between September 1, 1995 and June 30, 1996. Charts were assessed for evidence of delle formation, graft rejection, graft-related infection, graft thinning, or tube erosion.Results: Forty-four eyes of 44 patients were enrolled. Mean follow-up was 10.2 ± 4.0 months (range, 2.3 to 18.6 months). Infection, tube erosion, graft rejection, and graft-related inflammation did not occur. Five eyes were noted to have asymptomatic thinning of the patch without evidence of tube erosion.Conclusions: Preserved human cadaveric pericardial patch grafts appear to be well-tolerated for use with glaucoma drainage devices. As with other grafting material, potential for graft thinning is possible and further long-term experience is needed.

Krupin Disk Implantation for Complicated Glaucomas

BACKGROUND The Krupin Eye Valve with Disk (Krupin disk) is a glaucoma shunt that incorporates a slit valve intended to minimize early postoperative hypotony. METHODS The medical records of all patients who have undergone Krupin disk implantation at the Doheny Eye Institute between July 1990 and December 1992 (25 eyes of 25 patients) were reviewed. RESULTS Intraocular pressure (IOP) was reduced from a mean of 36.1 +/- 11.5 mmHg to 15.3 +/- 7.5 mmHg at follow-up intervals of 4 to 19 months (mean, 13.2 months). On the first postoperative day, IOPs ranged from 0 to 40 mmHg. In two eyes (8%), the IOP was less than 6 mmHg, and in five eyes (20%) the IOP was more than 21 mmHg. Serous choroidal effusion and/or choroidal hemorrhage occurred in seven patients (28%). Six- and 12-month life-table success rates (6 < or = IOP < or = 21 mmHg) were 84% and 66%, respectively. CONCLUSION The Krupin disk lowers IOP in most patients; however, the presence of a slit valve does not eliminate either early postoperative hypotony with its attendant complications or early IOP spikes.

Laser Suture Lysis after Mitomycm C Trabeculectomy

PURPOSE To evaluate the timing, efficacy, and complications of laser suture lysis (LSL) after mitomycin C trabeculectomy in patients with glaucoma at high risk for failure of filtering surgery. METHODS The authors retrospectively reviewed the charts of 62 consecutive patients who underwent a total of 66 sessions of LSL after trabeculectomy with mitomycin C. RESULTS The interval from surgery to LSL ranged from 2 to 65 days (mean +/- standard deviation, 17.9 +/- 14.9 days). The average intraocular pressure (IOP) reduction after LSL was 11.9 +/- 8.9 mmHg (range, 3-40 mmHg). A longer interval to LSL was correlated with a lesser degree of pressure reduction (P=0.0004, Wilcoxon rank-sum test). After LSL, hypotony developed in 13 (21%) patients (IOP < 6 mmHg on 2 consecutive measurements at least 24 hours apart). This resolved spontaneously after 7 to 304 days (104.1 +/- 109.1 days) in 12 (92%) of the 13 patients. Life-table success rates (success defined as 6 mmHg </= final IOP </= 21 mmHg) for the hypotony and no hypotony groups were 100% and 86% (at 6 months) and 96% and 86% (at 12 months), respectively. The final visual acuity worsened in a significantly greater percentage of patients in the hypotony group (46%) compared with the no-hypotony group (18%) (P = 0.06), Fishers exact test). CONCLUSIONS Laser suture lysis is safe and effective in augmenting aqueous filtration after mitomycin C trabeculectomy. A longer time interval between surgery and LSL may result in both a lesser degree of IOP reduction and a lower incidence of subsequent hypotony.

Ultrasound Biomicroscopy in Anterior Ocular Trauma

BACKGROUND AND OBJECTIVE The authors investigated the role of ultrasound biomicroscopy after ocular trauma. PATIENTS AND METHODS Ultrasound biomicroscopy was performed in six eyes of six patients at the New York Eye and Ear Infirmary after a variety of traumatic ocular injuries. RESULTS Eyes with angle recession, iridodialysis, cyclodialysis, hyphema, an intraocular foreign body, scleral laceration, and subluxed crystalline lens were imaged without complication. Ultrasound biomicroscopy aided in the diagnosis when visualization was limited by media opacities or distorted anterior segment anatomy. CONCLUSION Ultrasound biomicroscopy is a safe and effective adjunctive tool for the clinical assessment and management of ocular trauma, especially when visualization is limited and multiple traumatic injuries are involved.

Suprachoroidal Hemorrhage after Molteno Implantation

PURPOSE The objective of this study is to identify the rate and the associated risk factors for suprachoroidal hemorrhage (SCH) after Molteno drain implantation. METHODS Data from the Molteno pilot study and single versus double-plate Molteno study were reviewed retrospectively for the occurrence of SCH. Follow-up intervals, demographic variables, ocular data, and medical history were collected. RESULTS SCH occurred in 6% of the patients enrolled in the Molteno studies; all cases were delayed and none were intraoperative. Significantly associated factors in a multiple logistic regression for SCH were the extent of intraocular pressure (IOP) drop after surgery, the post-operative IOP, a diagnosis of angleclosure glaucoma, and possibly the number of prior surgeries as well. Eyes with SCH did significantly less well in terms of visual acuity outcomes and were more likely to have inadequately controlled IOP. CONCLUSIONS This study suggests that SCH occurs at the same frequency after Molteno implantation as after filtering surgery with antimetabolite use and that eyes with SCH do less well.

Aqueous Tube Shunt to a Pre-existing Episcleral Encircling Element in the Treatment of Complicated Glaucomas

PURPOSE The treatment of glaucoma after scleral buckling surgery is often problematic. The authors investigated a series of patients in whom a silicone tube was implanted to shunt aqueous from the anterior segment to the fibrous capsule surrounding a previously placed silicone episcleral encircling element. METHODS Thirteen patients were retrospectively reviewed. In each patient, a silicone tube was inserted through a small incision into the fibrous capsule overlying the scleral explant. In most patients, no attempt was made to secure the distal end of the tube to the silicone band. The proximal end of the tube was inserted into the eye via a needle track. RESULTS Successful control of intraocular pressure (IOP) (6 mm Hg < or = final IOP or < 21 mmHg with or without medication) was ultimately achieved in 11 (85%) of 13 patients (3 of the successful patients underwent one or more surgical revisions to relieve obstruction of the proximal and/or distal tube opening). Follow-up in these patients ranged from 8 to 49 months (mean +/- standard deviation, 21.7 +/- 14.1 months). The final postoperative visual acuities were within one line of the preoperative visual acuities or had improved in 11 (85%) patients. Complications included serous choroidal detachment (3 patients; 23%), conjunctival wound leak (2 patients; 15%), hyphema (1 patient; 8%), and tube obstruction by lens, iris, vitreous, or episcleral fibrous tissue (4 patients; 31%). CONCLUSION Aqueous tube shunt to a pre-existing episcleral encircling element is useful in treating complicated glaucomas after scleral buckling surgery. Fibrous obstruction of the external tube opening is a frequent complication in the early postoperative period, but it may be relieved by surgical revision.

Angle closure after Boston keratoprosthesis.

Purpose:To evaluate changes in the anterior chamber angle after Boston keratoprosthesis (KPro) placement. Patients/Methods:Ten patients were serially imaged with anterior segment optical coherence tomography after Boston KPro surgery. Angles were judged to be open or closed in the horizontal axis. Results:Seven of 10 patients had open angles before KPro placement. Within 4 months, 4 of 7 patients developed angle closure. Contact between the iris and the backplate was seen in 3 of these patients. Two of the 4 eyes demonstrated progressive angle closure. Intraocular pressure was elevated in 3 patients postoperatively due to the obstruction of a glaucoma drainage device tube (1 eye) and angle closure (2 eyes). Conclusions:After Boston KPro surgery, patients must be carefully monitored for the onset or progression of glaucoma. Progressive angle closure can occur after placement of a Boston KPro and may be seen in conjunction with irido-backplate touch.