The Short-term Effects of Artificial Tears on the Tear Film Assessed by a Novel High-Resolution Tear Film Imager: A Pilot Study

PURPOSE

The purpose of this study was to investigate the effects of artificial tears (AT) on the sublayers of the tear film assessed by a novel tear film imaging (TFI) device.

METHODS

The mucoaqueous layer thickness (MALT) and lipid layer thickness (LLT) of 198 images from 11 healthy participants, 9 of whom had meibomian gland disease, were prospectively measured before and after exposure to 3 different AT preparations (Refresh Plus; Retaine [RTA]; Systane Complete PF [SYS]), using a novel nanometer resolution TFI device (AdOM, Israel). Participants were assessed at baseline and at 1, 5, 10, 30, and 60 minutes after instilling 1 drop of AT during 3 sessions on separate days. Repeated-measures analysis of variances were used for comparisons with P < 0.05 considered significant.

RESULTS

For all ATs, the mean MALT was greatest 1 minute after drop instillation, with an increase of 67%, 55%, and 11% above the baseline for SYS, Refresh Plus, and RTA, respectively. The SYS formulation demonstrated the highest percentage increases in mean MALT and LLT at most postdrop time points. The MALT differences were significantly higher in the SYS than in the RTA (P = 0.014). After 60 minutes, no AT group demonstrated statistically significant changes in MALT or LLT compared with baseline.

CONCLUSIONS

We report, for the first time, the effects of AT on MALT and LLT using a high-resolution TFI. A substantial acute mean MALT increase occurs 1 minute after AT instillation with all agents tested, but there were clear differences in response and durability, suggesting the benefits of choosing specific AT according to the needs of each patient.

Choroidal Effusions after Glaucoma Drainage Implant Surgery: Risk Factors and Surgical Management

OBJECTIVE

To report the incidence of patients who developed choroidal effusions after glaucoma drainage implant (GDI) surgery and determine risk factors for and outcomes of surgical intervention.

DESIGN

Retrospective case series.

SUBJECTS

Medical records of 605 patients who underwent GDI surgery from January 1, 2017 to June 7, 2021 at New York University Langone Health and New York Eye and Ear Infirmary of Mount Sinai were reviewed.

METHODS

Preoperative, intraoperative, and postoperative clinical data were obtained. Multivariate logistic regression evaluated the factors associated with the need for surgical intervention. Patient records were analyzed for effusion resolution, intraocular pressure (IOP), visual acuity (VA), and complications across treatment modalities.

MAIN OUTCOME MEASURES

Incidence of choroidal effusion development and need for surgical intervention.

RESULTS

Choroidal effusions developed in 110 (18%) patients (110 eyes). Surgical intervention to drain the effusion or ligate the implant tube was performed in 19 (17%) patients. The average time to surgical intervention was 47.6 days. Among patients who developed postoperative effusions, risk factors for requiring surgical intervention included history of selective laser trabeculoplasty (SLT) (P = 0.004; odds ratio [OR], 14.4), prior GDI surgery (P = 0.04; OR 8.7), 350-mm2 Baerveldt glaucoma implant placement (P = 0.05; OR, 4.8), and anterior chamber shallowing (AC; P < 0.001; OR, 25.1) in the presence of effusions. The subgroup that required multiple surgeries for effusion resolution had a significantly lower mean IOP at the most recent follow-up compared with those who received medical management only (P < 0.001). A higher percentage of patients who required surgical intervention lost VA at the most recent follow-up compared with patients whose effusions resolved with conservative management (i.e., medical management, AC viscoelastic injection).

CONCLUSIONS

Choroidal effusions after GDI surgery resolved with conservative management in most patients. A history of SLT or GDI placement, implantation of a BGI-350, and the presence of a shallow chamber were risk factors for surgical intervention. Although interventions, such as surgical drainage are at times necessary, a better understanding of their impacts can help guide postoperative decisions. The risks and benefits of these procedures must be carefully considered in these high-risk eyes.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

“Persistence of Memory” – Multimodal imaging of delayed sympathetic ophthalmia

Purpose

To describe a case of late post-surgical sympathetic ophthalmia documented with multimodal imaging.

Observations

A 74-year-old male presented to the urgent care of the New York Eye and Ear Infirmary with blurry vision and discomfort in his left eye for three weeks. His vision was 20/50, with intraocular pressure of 13 mmHg, and slit lamp examination was significant for conjunctival congestion, 1+ anterior segment cell and flare, and diffuse keratic precipitates. His right eye was no light perception with a condensed hyphema, intraocular lens and inferonasal tube. His medical history included coronary artery bypass, prostate cancer, hyperlipidemia, and hypertension. His ocular history included blunt trauma to the right eye at age 11 with development of a traumatic macular hole and later rhegmatogenous retinal detachment at age 53, repaired with multiple vitreoretinal procedures. He developed glaucoma in the right eye and was treated with a tube shunt and ultimately transscleral cyclophotocoagulation (TSCPC) 7 years later, 13 years prior to his presentation of the left eye. Dilated fundus examination of his left eye revealed diffuse chorioretinal folds in the macula without any discrete chorioretinal lesions. Ultrasound of the right showed serous macular detachments with scleral thickening. Presumptive diagnosis of sympathetic ophthalmia was made and oral corticosteroid therapy was initiated. Subsequent SD-OCT and en-face OCT-A demonstrated Dalen-Fuchs nodules within the macula underlying areas of resolved serous detachment, after 6 weeks of oral steroids and initiation of immunomodulatory therapy (IMT).

Conclusions

Sympathetic ophthalmia may rarely present with very delayed onset, and TSCPC is an uncommon inciting event. These patients may develop serous detachment, choroidal folds and inflammatory nodules identifiable on exam and multimodal imaging, which can resolve when treated appropriately. OCT-A may provide utility in monitoring response to immunosuppressive treatment in these patients.

How glaucoma care changed for the better after the pandemic

PURPOSE OF REVIEW

The current article reviews enhancements to the delivery of glaucoma care that developed in response to the coronavirus disease 19 (COVID-19) pandemic and are likely to persist beyond its resolution.

RECENT FINDINGS

Literature from the review period (2020-2021) includes reports highlighting contributions of the ophthalmology community to global health during the pandemic. Glaucoma practices worldwide have instituted more robust infection control measures to mitigate severe acute respiratory syndrome coronavirus 2 transmission in the outpatient setting, and many of these modifications will endure in the post-COVID era. Operational adjustments have led to the provision of more efficient glaucoma care. A hybrid care model involving technician-based diagnostic testing and subsequent virtual consultation with a glaucoma specialist has evolved as a useful adjunct to traditional face-to-face encounters with patients.

SUMMARY

Glaucoma specialists, patients, and staff have adapted to a 'new normal' of glaucoma care delivery during the COVID-19 pandemic. Although innovation has propelled several improvements to glaucoma care during this global health crisis, significant barriers to more widespread implementation of teleglaucoma still exist. Whether, and in what capacity, the pandemic has permanently altered glaucoma practice patterns remains to be seen.

Open Conjunctival Approach for Sub-Tenon's Xen Gel Stent Placement and Bleb Morphology by Anterior Segment Optical Coherence Tomography

PRCIS

Sub-Tenon's implantation of the Xen Gel stent resulted in significant intraocular pressure (IOP) lowering along with a low rate of postoperative bleb needling, and a favorable bleb morphology on anterior segment optical coherence tomography (AS-OCT).

PURPOSE

The aim was to assess clinical outcomes and bleb morphology following sub-Tenon's implantation of the Xen Gel Stent.

METHODS

The medical records of patients who underwent sub-Tenon's Xen Gel Stent implantation with intraoperative mitomycin-C through an open conjunctival approach were reviewed. Postoperative IOP and number of glaucoma medications at 1, 3, 6, 9, and 12 months were assessed. Bleb morphology was analyzed at various timepoints using AS-OCT (Topcon DRI OCT version 1.1.1).

RESULTS

Twenty-six eyes were included in the study. Mean age was 69.4±8.0 years. Mean preoperative IOP was 28.1±7.8 mm Hg on an average of 3.5±0.9 glaucoma medications. Mean IOP at postoperative month 12 (n=23 eyes) was 12.9±4.0 mm Hg (P<0.01) on an average of 0.3±0.6 (P<0.01) glaucoma medications. Three eyes (12%) required postoperative needle revision. Bleb morphology in the early postoperative period (≤3 mo) was characterized by multiple small subconjunctival microcysts on AS-OCT. At the intermediate (6 to 12 mo) and long-term (>12 mo) timepoints, reduction in microcysts with multiple internal parallel layers of aqueous flow and a uniform pattern were more frequently noted. All functional blebs were characterized by the presence of a posterior episcleral fluid lake. Failed blebs showed absence of aqueous humor around the distal end of the microshunt.

CONCLUSION

Following an open conjunctival approach, sub-Tenon's placement of the Xen Gel Stent with significant IOP lowering was achieved. In eyes with good shunt function, bleb morphology by AS-OCT showed a posterior episcleral fluid lake similar to findings following trabeculectomy.

Glaucoma care during the coronavirus disease 2019 pandemic

PURPOSE OF REVIEW

The current article reviews the impact of the coronavirus disease 2019 (COVID-19) pandemic on the delivery of ophthalmic, and specifically, glaucoma care.

RECENT FINDINGS

Literature from the review period includes case series demonstrating the presence of severe acute respiratory syndrome coronavirus 2 RNA in the conjunctival secretions of patients with laboratory-confirmed COVID-19. The global ophthalmology community published reports outlining the enhanced infection control measures undertaken by different institutions around the world to mitigate transmission of the novel coronavirus. Telemedicine has been increasingly implemented in glaucoma practices to reduce in-office patient volume. New data regarding the efficacy and feasibility of tools for home monitoring of intraocular pressure, virtual visual field testing, and remote disc photography are reviewed.

SUMMARY

COVID-19 has posed a global public health threat due to the severity of its contagion and associated morbidity and mortality. Glaucoma specialists have responded to the pandemic with innovative modifications to reduce viral transmission and optimize patient and staff safety in the office and operating room. The role of teleglaucoma has expanded and will continue to evolve as remote diagnostic devices undergo further refinement and validation.

The Effect of Phacoemulsification on Intraocular Pressure in Eyes with Preexisting Glaucoma Drainage Implants

PURPOSE

To study the effect of phacoemulsification on intraocular pressure (IOP) control in patients with preexisting glaucoma drainage implants (GDIs).

DESIGN

Retrospective, observational case series.

PARTICIPANTS

A total of 45 patients (51 eyes) with previously placed GDIs who underwent phacoemulsification between January 2013 and March 2018.

METHODS

The list of patients was obtained from billing records. Clinical data were retrieved from the corresponding electronic medical records.

MAIN OUTCOME MEASURES

Intraocular pressure, number of glaucoma medications before and after phacoemulsification (postoperative day 1, week 1, months 1, 3, 6, 12, 18, and 24), rate of failure (failure defined as IOP >18 mmHg and IOP increase >20% at 2 consecutive visits after month 1, need for additional glaucoma surgery, or loss of light perception vision), and postoperative complications.

RESULTS

Mean follow-up was 23.0 ± 11.1 months. The average interval between GDI surgery and phacoemulsification was 9.4 ± 6.7 months. An Ahmed glaucoma valve (AGV; New World Medical) was implanted in 12 eyes, a Baerveldt glaucoma implant (BGI; Johnson & Johnson Surgical Vision) was implanted in 36 eyes, and a Molteno (Molteno Ophthalmic Limited) glaucoma implant was implanted in 3 eyes. Before phacoemulsification, the mean IOP was 14.4 ± 4.4 mmHg on 2.1 ± 1.3 glaucoma medications. At postoperative month 24, the mean IOP was 12.6 ± 4.4 mmHg (n = 29, P = 0.519) on 2.0 ± 1.6 (P = 0.457) glaucoma medications. The reduction in IOP was significant only at postoperative week 1 (P = 0.031). The cumulative failure rate was 3.9% at 1 year and 11.8% at 2 years. The AGV group had a significantly higher mean IOP before phacoemulsification than the BGI group (P = 0.016). Analysis of covariance, taking the baseline IOP as a covariate, revealed no differences in postoperative IOP and number of glaucoma medications between groups, except for month 18 (1 patient in the BGI group had uncontrolled IOP requiring surgery). Postoperative complications included cystoid macular edema (10%), corneal decompensation (6%), and choroidal effusion (4%).

CONCLUSIONS

Phacoemulsification after GDI surgery resulted in a transient reduction in IOP at postoperative week 1. Patients with previously placed AGVs had similar postoperative outcomes compared with those with BGIs.

Virtual Ophthalmology: Telemedicine in a COVID-19 Era

Purpose

To discuss the effects of the severe acute respiratory syndrome coronavirus 2 betacoronavirus on ambulatory ophthalmology practices, the value proposition of telemedicine, teleophthalmology implementation methodologies, and the accelerated future of telemedicine.

Design

Review of the current telehealth landscape including usage, policies, and techniques for ambulatory practice integration.

Methods

We provide author-initiated review of recent trends in telehealth, governmental recommendations for health care delivery during the COVID-19 pandemic, and a PubMed Central query for telemedicine in ophthalmology or teleophthalmology. In addition, the authors' comprehensive experience in telemedicine design and implementation is provided.

Results

We provide a summary describing the present state of telehealth, teleophthalmology modeling, care delivery, and the proposed impact of telehealth surges on the future of ophthalmology practice.

Conclusion

Recent patient and provider interest in telemedicine, the relaxation of regulatory restrictions, increased remote care reimbursement, and ongoing social distancing practices compel many ophthalmologists to consider virtualizing services.

Genetic Architecture of Primary Open-Angle Glaucoma in Individuals of African Descent: The African Descent and Glaucoma Evaluation Study III

PURPOSE

To find genetic contributions to glaucoma in African Americans.

DESIGN

Cross-sectional, case-control study.

PARTICIPANTS

One thousand eight hundred seventy-five primary open-angle glaucoma (POAG) patients and 1709 controls, self-identified as being of African descent (AD), from the African Descent and Glaucoma Evaluation Study (ADAGES) III and Wake Forest School of Medicine.

METHODS

MegaChip genotypes were imputed to Thousand Genomes data. Association of single nucleotide polymorphisms (SNPs) with POAG and advanced POAG was tested by linear mixed model correcting for relatedness and population stratification. Genetic risk scores were tested by receiver operator characteristic curves (ROC-AUCs).

MAIN OUTCOME MEASURES

Primary open-angle glaucoma defined by visual field loss without other nonocular conditions (n = 1875). Advanced POAG was defined by age-based mean deviation of visual field (n = 946).

RESULTS

Eighteen million two hundred eighty-one thousand nine hundred twenty SNPs met imputation quality of r2 > 0.7 and minor allele frequency > 0.005. Association of a novel locus, EN04, was observed for advanced POAG (rs185815146 β, 0.36; standard error, 0.065; P < 3×10-8). For POAG, an AD signal was observed at the 9p21 European descent (ED) POAG signal (rs79721419; P < 6.5×10-5) independent of the previously observed 9p21 ED signal (rs2383204; P < 2.3×10-5) by conditional analyses. An association with POAG in FNDC3B (rs111698934; P < 3.9×10-5) was observed, not in linkage disequilibrium (LD) with the previously reported ED SNP. Additional previously identified loci associated with POAG in persons of AD were: 8q22, AFAP1, and TMC01. An AUC of 0.62 was observed with an unweighted genetic risk score comprising 11 SNPs in candidate genes. Two additional risk scores were studied by using a penalized matrix decomposition with cross-validation; risk scores of 50 and 400 SNPs were identified with ROC of AUC = 0.74 and AUC = 0.94, respectively.

CONCLUSIONS

A novel association with advanced POAG in the EN04 locus was identified putatively in persons of AD. In addition to this finding, this genome-wide association study in POAG patients of AD contributes to POAG genetics by identification of novel signals in prior loci (9p21), as well as advancing the fine mapping of regions because of shorter average LD (FNDC3B). Although not useful without confirmation and clinical trials, the use of genetic risk scores demonstrated that considerable AD-specific genetic information remains in these data.

The African Descent and Glaucoma Evaluation Study (ADAGES) III: Contribution of Genotype to Glaucoma Phenotype in African Americans: Study Design and Baseline Data

PURPOSE

To describe the study protocol and baseline characteristics of the African Descent and Glaucoma Evaluation Study (ADAGES) III.

DESIGN

Cross-sectional, case-control study.

PARTICIPANTS

Three thousand two hundred sixty-six glaucoma patients and control participants without glaucoma of African or European descent were recruited from 5 study centers in different regions of the United States.

METHODS

Individuals of African descent (AD) and European descent (ED) with primary open-angle glaucoma (POAG) and control participants completed a detailed demographic and medical history interview. Standardized height, weight, and blood pressure measurements were obtained. Saliva and blood samples to provide serum, plasma, DNA, and RNA were collected for standardized processing. Visual fields, stereoscopic disc photographs, and details of the ophthalmic examination were obtained and transferred to the University of California, San Diego, Data Coordinating Center for standardized processing and quality review.

MAIN OUTCOME MEASURES

Participant gender, age, race, body mass index, blood pressure, history of smoking and alcohol use in POAG patients and control participants were described. Ophthalmic measures included intraocular pressure, visual field mean deviation, central corneal thickness, glaucoma medication use, or past glaucoma surgery. Ocular conditions, including diabetic retinopathy, age-related macular degeneration, and past cataract surgery, were recorded.

RESULTS

The 3266 ADAGES III study participants in this report include 2146 AD POAG patients, 695 ED POAG patients, 198 AD control participants, and 227 ED control participants. The AD POAG patients and control participants were significantly younger (both, 67.4 years) than ED POAG patients and control participants (73.4 and 70.2 years, respectively). After adjusting for age, AD POAG patients had different phenotypic characteristics compared with ED POAG patients, including higher intraocular pressure, worse visual acuity and visual field mean deviation, and thinner corneas (all P < 0.001). Family history of glaucoma did not differ between AD and ED POAG patients.

CONCLUSIONS

With its large sample size, extensive specimen collection, and deep phenotyping of AD and ED glaucoma patients and control participants from different regions in the United States, the ADAGES III genomics study will address gaps in our knowledge of the genetics of POAG in this high-risk population.

Optical Coherence Tomography Angiography Analysis of Perfused Peripapillary Capillaries in Primary Open-Angle Glaucoma and Normal-Tension Glaucoma

Purpose

To compare perfused peripapillary capillary density in primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), and normal patients using optical coherence tomography angiography (OCT-A).

Methods

A retrospective review of POAG, NTG, and normal patients imaged with OCT-A was performed. En face OCT angiograms identifying peripapillary vessels were obtained using a spectral-domain OCT system (Avanti RTVue-XR). A custom image analysis approach identified perfused peripapillary capillaries, quantified perfused capillary density (PCD), and generated color-coded PCD maps for 3.5- and 4.5-mm-diameter scans. We compared PCD values, PCD maps, standard automated perimetry (Humphrey visual field [HVF]) parameters, and OCT retinal nerve fiber layer (RNFL) thickness analyses across all groups.

Results

Forty POAG, 26 NTG, and 26 normal patients were included. Annular PCD in POAG (34.24 ± 6.76%) and NTG (37.75 ± 3.52%) patients was significantly decreased compared to normal patients (42.99 ± 1.81%) in 4.5-mm scans (P < 0.01 and P < 0.01, respectively). Similar trends and statistical significances were seen in 3.5-mm scans. Linear regression analysis resulted in moderate correlations between annular PCD values and other glaucomatous parameters. Pearson coefficients comparing annular PCD from 4.5-mm scans in POAG and NTG groups to HVF mean deviation, HVF pattern standard deviation, and average RNFL thickness all showed statistical significance (P < 0.05). Color maps showed that POAG and NTG patients had a reduction of perfused capillaries that progressed in size when comparing early, moderate, and severe glaucoma groups.

Conclusions

Optical coherence tomography angiography can uniquely identify changes in peripapillary PCD in glaucoma patients. Optical coherence tomography angiography may offer insights into the pathophysiology of glaucomatous damage and risk factors for disease progression.

Scleral fistula closure at the time of glaucoma drainage device tube repositioning: a novel technique

Repositioning a glaucoma drainage device tube from the anterior chamber to the ciliary sulcus or pars plana can be a challenging procedure owing to the difficulty in obtaining tight closure of the original limbal fistula. Failure to achieve watertight and airtight closure of the fistula can result in substantial difficulty in completing other key portions of the surgery and may lead to postoperative hypotony and associated complications. A novel technique using a Tutoplast scleral plug, polyglactin sutures, and, in certain cases, fibrin tissue sealant to close a limbal fistula at the time of glaucoma drainage device tube repositioning is described. This technique can be replicated with ease and provides a tight seal so that other concurrent surgical procedures can safely be completed and postoperative hypotony is avoided.

Laser tube ligature release following aqueous shunt implantation in young children

The implantation of non-valved aqueous shunting devices in children is often complicated by intraocular pressure elevation in the early postoperative period, during which time the tube is closed with a temporary suture ligature to avoid hypotony. Release of a polyglactin suture ligature using conventional laser lysis is not possible in young children in the clinic setting. The authors describe a minimally invasive technique using a portable green diode (532-nm) laser delivered through a standard endoprobe and a Hoskins laser suture lysis lens to disrupt a polyglactin suture ligature following pars plana aqueous shunt implantation in a young child.

Sequential glaucoma implants in refractory glaucoma

PURPOSE

To evaluate the efficacy of a second glaucoma implant in eyes with prior glaucoma implant surgery and inadequate intraocular pressure (IOP) control.

DESIGN

Retrospective observational cohort study.

METHODS

Patients undergoing a second glaucoma implant surgery from 1996 to 2008 were included. Outcome measures included visual acuity, IOP, glaucoma medication use, and complications. Success was defined as IOP < 21 mm Hg (criterion 1) and IOP < 17 mm Hg (criterion 2), with at least 25% reduction in IOP and no prolonged hypotony.

RESULTS

Forty-three eyes (43 patients) had a mean follow-up of 32.6 +/- 21.6 months. Life-table analysis demonstrated success rates of 93%, 89%, and 83% using criterion 1 and 83%, 75%, and 75% using criterion 2 at 1, 2, and 3 years, respectively. At last follow-up, mean IOP (13.6 +/- 4.6 vs 24.7 +/- 7.5 mm Hg; P < .001) and mean number of medications (1.4 +/- 1.2 vs 3.9 +/- 1.2; P < .001) were lower following the second implant. There was no difference in preoperative and most recent logarithm of the minimal angle of resolution (logMAR) visual acuities (0.86 +/- 0.13 vs 1.1 +/- 0.13; P = .07). The most frequently used second implants were similar in percentage IOP reduction (Baerveldt implant, 45 +/- 19%; Ahmed valve, 40 +/- 18%; P = .4).

CONCLUSIONS

A second glaucoma implant may effectively lower IOP in eyes with refractory glaucoma.

Outcomes of Inferonasal Baerveldt Glaucoma Drainage Implant Surgery

PURPOSE

To determine the outcomes of inferonasal Baerveldt glaucoma implant (BGI) surgery.

PATIENTS AND METHODS

A retrospective, non-comparative case series of 182 eyes of 182 patients who underwent inferonasal placement of a Baerveldt glaucoma implant. The main outcome measures included intraocular pressure, number of glaucoma medications, best corrected visual acuity, and complications.

RESULTS

Patients were followed for an average (+/- SD) of 19 +/- 15 months. Median Snellen visual acuity was unchanged at last follow-up. Intraocular pressure was reduced from a mean (+/- SD) of 28.6 +/- 11.5 mm Hg preoperatively to 13.4 +/- 5.7 mm Hg at most recent follow-up (P < 0.001). The number of antiglaucoma medications was reduced from a mean (+/- SD) of 2.7 +/- 1.3 preoperatively to 1.1 +/- 1.1 at most recent follow-up. Nineteen eyes met our criteria for failure, yielding a cumulative percent survival of 92% at 12 months, 88% at 24 months, and 77% at 44 months. The most common complications were hyphema (14 eyes, 8%), choroidal effusion (12 eyes, 7%), and corneal decompensation (19 eyes, 10%). Endophthalmitis and diplopia occurred rarely (1 eye, <1%; 3 eyes, 2%, respectively).

CONCLUSIONS

Inferonasal Baerveldt glaucoma implant placement appears to be a safe and effective surgical option that may be helpful in certain clinical situations.

Management of refractory glaucoma in childhood

Glaucoma in children is characterized by marked intraocular pressure (IOP) elevation with resultant atrophy of the optic nerve and loss of retinal ganglion cells. In very young children, secondary expansion of the globe with damage to anterior segment structures, such as the cornea and zonule, often occurs. Permanent, severe visual dysfunction may result from optic nerve damage as well as from amblyopia arising from anisometropia and corneal opacification. The treatment of childhood glaucoma often involves surgery. Goniotomy and trabeculotomy remain the first line surgical procedures for open-angle glaucoma in children. Trabeculectomy with adjunctive antifibrosis therapy, aqueous shunt surgery, and cyclodestructive procedures are undertaken when angle surgery fails to control the IOP or is unlikely to succeed. The choice of surgical procedure is individualized according to factors such as the age of the patient, the specific type of glaucoma, the number of prior surgical procedures, and the visual potential of the eye. Achieving and maintaining an adequate IOP to prevent progressive optic nerve damage, avoiding complications, and preserving vision are the goals that must be considered in deciding on a surgical plan.

Glaucoma drainage tube kink after pars plana insertion

PURPOSE

To describe focal obstruction of drainage tubes by kinking at the scleral entry site after pars plana insertion.

METHODS

Case study.

RESULTS

Three eyes of three patients underwent uncomplicated placement of a Baerveldt implant into the vitreous cavity at the time of pars plana vitrectomy. Intraocular pressure remained increased after the procedure without evidence of flow. Surgical exploration and modification of the tube placement resulted in immediate intraocular pressure reduction. Compression of the tube at the scleral entry site was confirmed intraoperatively in all eyes by ultrasound biomicroscopy.

CONCLUSION

Kinking of the tube at its scleral entry site should be recognized as a possible cause of increased intraocular pressure without bleb formation after pars plana insertion of a glaucoma drainage implant.

Pars plana tube insertion of glaucoma drainage implants and penetrating keratoplasty in patients with coexisting glaucoma and corneal disease

PURPOSE

To determine the efficacy and associated complications of glaucoma drainage implant (GDI) surgery with pars plana tube insertion and penetrating keratoplasty (PK) in eyes with glaucoma and corneal disease.

DESIGN

Retrospective, interventional case series.

PARTICIPANTS

All patients who underwent both GDI surgery with pars plana tube insertion and PK before September 1997 were included.

METHODS

The medical records of 34 consecutive patients (34 eyes) who had undergone GDI (Baerveldt, Pharmacia & Upjohn, Kalamazoo, MI; Molteno, IOP INC:, Costa Mesa, CA; Krupin, Hood Laboratories, Pembroke, MA; or Ahmed, New World Medical, Rancho Cucamonga, CA) insertion before, concurrent with, or after PK were reviewed retrospectively. All corneal grafts were clear before GDI surgery for patients who underwent glaucoma surgery after PK. Outcomes were evaluated using Kaplan-Meier life-table analysis.

MAIN OUTCOME MEASURES

Clinical outcome assessment included corneal graft clarity, intraocular pressure (IOP), visual acuity, and identification of complications.

RESULTS

Mean follow-up after completion of both GDI surgery and PK was 12.1 +/- 8.4 months (range, 0-31.8 months). Twelve- and 24-month life-table rates for complete success after both GDI and PK were 63% and 33%, respectively. Twelve- and 24-month life-table success rates for IOP control and corneal graft clarity were 85% and 62%, and 64% and 41%, respectively. Final postoperative visual acuity was the same as or better than (> or =2 Snellen lines) the preoperative level in 29 patients (85%). One or more posterior segment complications occurred in 15 (44%) patients.

CONCLUSIONS

Pars plana tube insertion of GDIs is a reasonable option for patients who have undergone PK or in whom PK is anticipated, despite the need for a complete pars plana vitrectomy. Although complications related to limbal tube placement are avoided, the incidence of posterior segment complications may be higher for pars plana insertion. The potential for enhanced corneal graft survival with pars plana versus anterior segment tube placement warrants further investigation.

Trabeculectomy with mitomycin-C in the treatment of pediatric glaucomas

PURPOSE

To evaluate the effectiveness and safety of trabeculectomy with mitomycin-C (MMC) in the management of childhood glaucomas.

DESIGN

Retrospective, noncomparative case series.

PARTICIPANTS

All patients less than 18 years of age who underwent trabeculectomy with MMC from June 1991 through October 1997 were included.

METHODS

The medical records of 29 consecutive patients (29 eyes) were reviewed. Data collected during routine patient follow-up were analyzed. Surgical outcome was evaluated using Kaplan-Meier life-table analysis.

MAIN OUTCOME MEASURES

Clinical outcome assessment included intraocular pressure (IOP) control, visual acuity, and identification of complications. Successful IOP control was defined as 5 mmHg < or = final IOP < or = 21 mmHg, with or without antiglaucoma medications and without further glaucoma surgery or loss of light perception. Outcomes for the group of patients with primary infantile glaucoma were compared with those for the group with secondary glaucomas.

RESULTS

Mean patient age was 6.4 +/- 4.4 years (range, 0.2-15.3 years). A variety of primary and secondary glaucomas were represented. Mitomycin-C (0.5 mg/ml) on a surgical sponge was applied to the episcleral surface for an average of 3.8 +/- 1.0 minutes (range, 1.5-5.0 minutes). Mean follow-up time for patients categorized as successes was 25.1 +/- 16.0 months (range, 5.5-59.7 months). The 12-, 24-, and 36-month life-table success rates for IOP control were 82%, 59%, and 59% respectively. There was no difference between the primary infantile glaucoma group and the secondary glaucoma group with respect to length of follow-up, rate of successful IOP control, and incidence of complications. Five patients (17%) experienced late bleb-related infection (BRI) at an average of 27.9 +/- 18.1 months (range, 5.4-55.5 months) after surgery. Other complications included hyphema, retinal detachment, late-onset bleb leak, flat anterior chamber, chronic hypotony, decompression retinopathy, suture abscess, and phthisis.

CONCLUSIONS

Trabeculectomy with MMC may be useful in the management of childhood glaucomas in which goniotomy, trabeculotomy, or both have failed. However, the high incidence of BRI in this series over an extended follow-up interval dictates caution in using MMC as an adjunct in pediatric trabeculectomy.

Trabeculectomy with intraoperative 5-fluorouracil

BACKGROUND AND OBJECTIVE

To investigate the outcome and complication rates of trabeculectomy following the combined use of intraoperative, topical 5-fluorouracil (5-FU) and low-dose, postoperative subconjunctival 5-FU injections.

PATIENTS AND METHODS

Forty-one eyes of 41 patients with advanced, medically uncontrolled glaucoma underwent trabeculectomy with intraoperative episcleral application of 5-FU (50 mg/ml for 5 minutes). A variable number of subconjunctival 5-FU injections were administered postoperatively at the discretion of the operating surgeon.

RESULTS

Six-, 12-, and 15-month life-table success rates (5 mm Hg < or = intraocular pressure [IOP < or = 21 mm Hg) were 100%, 97%, and 83%, respectively. Mean postoperative IOP was 12.1 +/- 4.3 mm Hg. An average of 2.2 +/- 1.6 (range 0 to 7) supplemental subconjunctival 5-FU injections were administered postoperatively. Corneal epithelial erosions developed in 7 (17%) of the eyes. Five of 7 patients who underwent subsequent surgical procedures maintained successful control of IOP at an average of 11.0 +/- 4.8 (range 5 to 16) months after the secondary surgery.

CONCLUSION

Trabeculectomy with intraoperative 5-FU is effective in controlling IOP while possibly minimizing the need for frequent postoperative injections and the occurrence of corneal epitheliopathy.

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.

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.

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.

Laser suture lysis after mitomycin 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), Fisher's 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.

Tissue plasminogen activator and glaucoma drainage implants

PURPOSE

The tube lumen of a glaucoma drainage implant is prone to occlusion by a blood or fibrin clot due to its small caliber, relatively low flow rate, and the plasmoid nature of the aqueous humor passing through it in the early postoperative period. The use of tissue plasminogen activator in the management of drainage tube obstruction is described herein.

METHODS

Two cases of drainage tube obstruction in patients with neovascular glaucoma treated with an intracameral injection of tissue plasminogen activator are reported.

RESULTS

Resolution of tube obstruction following tissue plasminogen activator administration with spontaneous lowering of the intraocular pressure and bleb formation was achieved in both cases. Differentiation of tube obstruction from other causes of elevated intraocular pressure following installation of glaucoma drainage devices is discussed.

CONCLUSION

The intracameral injection of tissue plasminogen activator may relieve drainage tube obstruction secondary to a blood or fibrin clot, even in the absence of any visible clot covering the proximal tube ostium or within the anterior chamber portion of the tube. This approach should be considered, in selected cases, prior to more invasive surgical revision.

Echographic evaluation of primary cysts of the iris pigment epithelium

PURPOSE

Primary cysts of the iris pigment epithelium frequently appear to be focal elevations of the peripheral iris. To differentiate them from other anterior segment tumors requires the ability to assess the distribution, tissue characteristics, and progression of such lesions, which we accomplished by using anterior segment echography.

METHODS

We reviewed the medical records of 49 consecutive patients referred to the Doheny Eye Institute for echographic evaluation of focal bulging of the peripheral iris. Echography of the anterior segment was performed on each patient by using an immersion technique. Clinical examination was also performed on 20 (41%) patients at the time of initial examination.

RESULTS

We identified 52 iris pigment epithelial cysts in 52 eyes of the 49 patients studied. All lesions were single, localized to the posterior iris surface, and demonstrated a well-circumscribed, echolucent structure on B-scan echography. Average maximal sagittal thickness was 1.6 +/- 0.4 mm. Cysts were most frequently located in the inferotemporal quadrant (31%). Minimal increase in size or regression of lesions was noted in the nine patients (ten eyes) for whom follow-up echographic examinations were available.

CONCLUSIONS

Primary iris pigment epithelial cysts possess characteristic features with regard to location, size, and internal structure, which can be accurately documented with echography. Clinically evident lesions tend to be between 1 and 4 mm in maximum sagittal thickness, conform to the contour of posterior chamber structures without distortion, produce anterior bulging of the peripheral iris, are preferentially located in the inferotemporal quadrant, and demonstrate limited potential for growth.

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.

Experience with the baerveldt implant in young patients with complicated glaucomas

PURPOSE

Previous studies have suggested that glaucoma shunt implantation may be useful in the management of glaucoma in young patients in whom goniotomy and/or trabeculotomy have failed or are inappropriate. Herein, we describe our initial experience with Baerveldt implantation in young patients with complicated glaucomas.

METHODS

Charts of all patients with glaucoma who were under 21 years of age, and who underwent Baerveldt implantation between March 1, 1991 and March 1, 1993 with at least a 6-month follow-up (30 eyes of 30 patients) were reviewed retrospectively.

RESULTS

The patients' ages ranged from 2 months to 20 years (mean, 6.6 +/- 6.4 years) with follow-up of 6-25 months (mean, 15.0 +/- 6.3 months). Intraocular pressure (IOP) was reduced from a preoperative range of 17-78 mm Hg (mean, 35.5 +/- 13.1 mm Hg) to a range of 6-22 mm Hg (mean, 13.5 +/- 4.2 mm Hg) postoperatively. Six- and 12-month life-table success rates (6 +/- IOP +/- 21 without additional glaucoma surgery or devastating complication) were 93% and 86%, respectively.

CONCLUSION

Baerveldt implantation is a useful approach to the treatment of glaucoma in young patients with complicated glaucomas.

Delayed-onset pneumococcal endophthalmitis after mitomycin-C trabeculectomy: association with cryptic nasolacrimal obstruction

PURPOSE

Delayed-onset endophthalmitis is a well-recognized complication of glaucoma filtering surgery, but, to our knowledge, no previous reports have associated this entity with occult nasolacrimal duct obstruction.

METHODS

A 16-month-old girl developed endophthalmitis 1 month after a mitomycin-C trabeculectomy for congenital glaucoma. A diagnostic pars plana vitrectomy, anterior chamber paracentesis, and injection of intravitreal antibiotics were performed.

RESULTS

Streptococcus pneumoniae was cultured from the aqueous and vitreous samples. Gradual clearing of the infection was achieved with systemic, intravitreal, and topical antibiotic therapy. Examination following resolution of the infection revealed complete obstruction of the ipsilateral nasolacrimal duct.

CONCLUSIONS

The high incidence of Streptococcus pneumoniae as the causative organism in delayed-onset endophthalmitis following glaucoma filtering surgery may be related, in part, to preexisting lacrimal outflow obstruction. Careful preoperative evaluation with attention to lacrimal outflow disorders is imperative prior to glaucoma filtering surgery, especially in children.

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.

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.

Aqueous tube shunt to a preexisting 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.

Epithelial ingrowth and glaucoma drainage implants

BACKGROUND

The authors report four cases of conjunctival epithelial invasion into the fibrous capsule surrounding a Baerveldt glaucoma implant. All cases were associated with concurrent or recent prior scleral buckling surgery.

METHODS

Three patients had postoperative conjunctival wound leaks, one in the immediate postoperative period and the other two at 9 and 17 days postoperatively after release of the tube ligature. In the fourth patient, a fistulous tract developed over the implant after a first-stage insertion. Histopathologic confirmation of subconjunctival epithelialization was obtained in two of these patients.

RESULTS

Surgical revision was performed in all patients. Excision and debridement of all epithelium-lined subconjunctival tissues and extensive bipolar cautery were used in the three patients with wound leaks. Implant removal also was performed in one of these. Fistulectomy and bipolar cautery were used in the fourth patient. No recurrent wound leaks or other adverse sequelae were noted.

CONCLUSIONS

Epithelial invasion of the subconjunctival space and inner bleb wall after implantation of glaucoma drainage devices can lead to breakdown of the conjunctival wound and persistent aqueous leak. Prior or concurrent scleral buckling surgery may predispose to this occurrence. Surgical revision involving epithelial debridement, cautery, and meticulous wound closure, with or without implant removal, has been used successfully in the management of this complication.

Glaucoma drainage implants

Glaucoma drainage implants provide a useful option in the management of complicated glaucomas for which the risk of failure of conventional filtering surgery is high. The basic design of these devices is similar; a silicone tube shunts aqueous humor from the anterior chamber to a fibrous capsule surrounding a synthetic plate or band positioned at the equatorial region of the globe. The capsule serves as a reservoir for aqueous drainage. Drainage implants have been used in the treatment of various refractory glaucomas, including those associated with aphakia and pseudophakia, prior unsuccessful filtering surgery, anterior segment neovascularization, trauma, youth, uveitis, epithelial downgrowth, iridocorneal endothelial syndrome, vitreoretinal disorders, and penetrating keratoplasty. Modifications in implant design and surgical technique have been developed to limit the occurrence of postoperative complications such as hypotony and its related sequelae, and strabismus.

Ocular findings in Treacher Collins syndrome

We examined 14 patients from nine families referred with the diagnosis of Treacher Collins syndrome. We noted seven significant ocular findings including the following: a subnormal horizontal palpebral fissure length and inferomedial displacement of the lateral canthus in primary gaze; further medial displacement (4.0 mm or more) of the lateral canthus with resultant shortening of the horizontal fissure length on forced eyelid closure (fissure narrowing sign); partial-thickness eyelid colobomata localized to the nasal one half to two thirds of the lower eyelids; bilateral absence of the inferior lacrimal puncta; bilateral blepharoptosis; inferior displacement of the palpebral fissures; and regular astigmatism without any consistent orientation of the axis of astigmatism relative to the lower eyelid defects, blepharoptosis, or lateral canthus. The fissure narrowing sign correlates with known anatomic deficiencies in the Treacher Collins syndrome and may prove valuable in confirming the diagnosis in patients who lack certain typical features.