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Biomedical subjects

R Ritch

Publications and source records attributed to R Ritch.

At least 19 recordsLinked to original sources
PubMed1998

Late-onset bleb leaks after glaucoma filtering surgery.

OBJECTIVE: To determine the incidence of focal, late-onset, conjunctival bleb leaks after glaucoma filtering surgery. DESIGN: Prospective, cross-sectional analysis. SETTING: Tertiary care outpatient referral center. PATIENTS: Consecutive patients who underwent glaucoma filtering surgery prior to June 1996 presenting for evaluation from September 2,1996, through November 15,1996. Five hundred twenty-five eyes of 525 consecutive patients were enrolled in the study. INTERVENTION: Bleb height (elevated or flat), area (diffuse or localized), and wall thickness (thin, thick, or encapsulated) were classified. Each bleb was tested for focal leakage using a moistened fluorescein strip, cobalt blue illumination, and slit-lamp biomicroscopy. Diffuse transconjunctival aqueous flow did not qualify as a focal leak. MAIN OUTCOME MEASURE: Seidel-positive aqueous leakage. RESULTS: Bleb leakage occurred in 14 eyes following trabeculectomy (mitomycin C treatment, 10 eyes; 5-fluorouracil treatment, 3 eyes; no antifibrosis agent, 1 eye) and in 1 eye following combined cataract and glaucoma surgery with adjunctive mitomycin C therapy. Bleb leakage occurred more frequently in eyes that received mitomycin C (10 [3.7%] of 273 eyes) than 5-fluorouracil (3 [1.4%] of 213 eyes) or no antifibrosis agent (1 [2.6%] of 39 eyes), using Kaplan-Meier estimates (P=.008, log-rank test). Conjunctival blebs were significantly thinner after trabeculectomy with mitomycin C than with 5-fluorouracil (P=.001). Bleb wall thickness was greater following combined cataract and glaucoma surgery than following trabeculectomy alone (P=.008). Age (P=.84), sex (P=.68), race (P=.77), duration of mitomycin C exposure (P=.62), number of antiglaucoma medications (P=.16), and total 5-fluorouracil dose (P=.85) were not associated with late-onset leaks. CONCLUSIONS: The risk of late-onset focal bleb leakage increases following trabeculectomy with mitomycin C therapy. Late leakage after combined cataract and glaucoma surgery is infrequent.

Adolescent↗
PubMed1998

Angle-closure glaucoma associated with occult annular ciliary body detachment.

OBJECTIVE: To evaluate the role of annular ciliary body detachment in the development of postoperative angle-closure glaucoma. DESIGN: Case series. SETTING: Tertiary care glaucoma referral center. METHODS: High-resolution, anterior segment ultrasound biomicroscopy, ophthalmoscopy, and B-scan ultrasonography were performed on 6 eyes of 6 patients with a clinical diagnosis of postoperative malignant glaucoma. RESULTS: Each eye had an elevated intraocular pressure, a shallow anterior chamber, 1 or more patent iridectomies, and no ophthalmoscopic or B-scan ultrasound evidence of serous or hemorrhagic ciliochoroidal detachment. Ultrasound biomicroscopy revealed annular ciliary body detachment in each eye. In 4 eyes, observation with topical medical treatment was associated with deepening of the anterior chamber, reduced intraocular pressure, and resolution of the detachment. Drainage of the supraciliary fluid was performed in 2 eyes. CONCLUSION: Occult, annular, serous detachment of the ciliary body may cause postoperative angle-closure glaucoma. This entity is clinically indistinguishable from malignant glaucoma. Ultrasound biomicroscopy facilitates the diagnosis.

Aged↗
PubMed1998

The Glaucoma Symptom Scale. A brief index of glaucoma-specific symptoms.

OBJECTIVE: To develop a brief symptom survey specific for persons with glaucoma, the Glaucoma Symptom Scale (GSS). DESIGN: Cross-sectional study of symptoms, functional impairment, and vision-targeted health-related quality of life among persons with glaucoma. PATIENTS: A sample of 147 persons with glaucoma among a broad range of treatment categories from 4 tertiary care glaucoma centers and 44 persons without eye disease enrolled from the same 4 centers. MAIN OUTCOME MEASURES: Participants completed a modified version of the Ocular Hypertension Treatment Study 10-item symptom checklist. Participants also completed 2 vision-specific measures, the National Eye Institute Visual Function Questionnaire and the VF-14. Participants underwent a clinical evaluation, including ocular and medical history, dilated ophthalmic examination, and Humphrey 24-2 automated visual field testing. RESULTS: The GSS has 2 underlying domains that demonstrate sufficient internal consistency reliability for between-group comparisons. The GSS discriminates well between persons with and without glaucoma. Additionally, tests of association with clinical markers of glaucoma severity support the clinical validity of the measure and tests of association with established vision-targeted measures provide evidence of construct validity. CONCLUSION: The simplicity, brevity, and psychometric properties of the GSS support its use in clinical practice and research to quantify symptoms in patients with glaucoma and to assist in investigations concerning the effect of glaucoma and treatments.

Cross-Sectional Studies↗
PubMed1998

Latanoprost treatment for glaucoma: effects of treating for 1 year and of switching from timolol. United States Latanoprost Study Group.

PURPOSE: To determine the efficacy and safety of latanoprost treatment for 1 year in glaucoma patients, and to evaluate the effects of switching from timolol to latanoprost therapy. METHODS: Latanoprost 0.005% was topically applied once daily without masking for 6 months in 223 patients with elevated intraocular pressure after previous treatment with latanoprost once daily or 0.5% timolol twice daily for 6 months in a multicenter, randomized, double-masked, parallel group study. RESULTS: Compared with baseline values before treatment, a significant (P < .0001) diurnal reduction in intraocular pressure of 6 to 8 mm Hg was maintained with minimal fluctuation for the duration of treatment. When treatment was switched from timolol to latanoprost, intraocular pressure was reduced by 1.5 +/- 0.3 mm Hg (mean +/- SEM; 8% change in intraocular pressure; 31% of the intraocular pressure reduction produced by timolol; P < .001) compared with the change in intraocular pressure in patients remaining on latanoprost therapy. Of the patients initially enrolled, 95% successfully completed treatment. There was a slight overall increase in conjunctival hyperemia in patients who switched from timolol to latanoprost, but no change in those who continued latanoprost. The timolol-induced reduction of resting heart rate returned to baseline levels after switching to latanoprost. Of the 247 patients treated with latanoprost during the masked and/or open-label studies, 12 (5%) demonstrated a definite (n = 4) or possible (n = 8) increase in iris pigmentation. CONCLUSIONS: Latanoprost is a well-tolerated ocular hypotensive agent that appears to be more effective than timolol in reducing intraocular pressure. The increase in iris pigmentation appears to be harmless but requires further investigation.

Adult↗
PubMed1998

High-resolution ultrasound biomicroscopy of the pars plana and peripheral retina.

OBJECTIVE: This study aimed to evaluate the ability and role of ultrasound biomicroscopy in imaging the peripheral retina, pars plana, and anterior choroid. DESIGN: The study design was a case series. PARTICIPANTS: Seventeen eyes of 17 patients with a variety of clinical diagnoses involving the anterior portion of the posterior segment were studied. INTERVENTION: High-frequency (50 MHz), high-resolution (50 microns) ultrasound biomicroscopy was performed. RESULTS: Ultrasound biomicroscopy was capable of imaging the peripheral retina, pars plana, and anterior choroid. Images had features consistent with known histopathology. Retinoschisis consisted of one thin hyper-reflective echo and could be differentiated from a retinal detachment, which was thicker and formed a bilayered echo. A choroidal effusion could be identified as an echolucent space within the suprachoroidea, whereas a choroidal hemorrhage was moderately echodense. Inflammatory diseases, such as a sarcoid granuloma, pars planitis, and Harada's disease, were characterized by different forms of uveal thickening. A ciliochoroidal nevus was internally hyporeflective and could be measured accurately and localized. CONCLUSIONS: Imaging of the peripheral retina, pars plana, and anterior choroid is possible with ultrasound biomicroscopy and may aid in the diagnosis and management of pathology involving this region.

Adolescent↗
PubMed1998

Novel trabecular meshwork inducible glucocorticoid response mutation in an eight-generation juvenile-onset primary open-angle glaucoma pedigree.

OBJECTIVE: This study aimed to update a large kindred with juvenile-onset primary open-angle glaucoma (POAG) first described in 1940 and to identify the underlying genetic cause of the disease. DESIGN: Molecular genetic study of a single kindred, including clinical examination, retrospective review of clinical and family history records, linkage analysis, and mutation screening. PARTICIPANTS: The retrospective review included 957 members of a single large family. The linkage study included 40 members of 1 branch of the family in which juvenile-onset POAG is segregating in an autosomal-dominant pattern. Mutation screening included 15 at-risk family members with juvenile-onset POAG, probands of 40 families with adult-onset POAG, probands of 11 additional unrelated juvenile-onset POAG families, and 43 unrelated normal control subjects. INTERVENTION: Clinical and family history records were obtained, ophthalmologic examinations were performed, and blood samples were drawn for use in genotyping. MAIN OUTCOME MEASURES: Allele sizes of microsatellite repeat genetic markers from the vicinity of the GLC1A glaucoma gene on chromosome 1q were assigned based on size fractionation of DNA fragments generated by polymerase chain reaction (PCR). Linkage was established by the method of lod scores. Mutations were identified by determination of the DNA sequence of PCR products amplified from the trabecular meshwork inducible glucocorticoid response (TIGR) gene. Glaucoma status for purposes of linkage and mutation analysis was based on a combination of ophthalmologic examination, clinical records, family history, and previously published information. For some individuals reported in the pedigree, but not included in the genotyping studies, less information was available as presented in the text and tables. RESULTS: Autosomal-dominant POAG was confirmed or reported for 78 members of an 8-generation family. Linkage analysis showed significant evidence for linkage of juvenile-onset POAG in one branch of the family to D1S452 (maximum lod score of 6.42 at a recombination fraction of 0.00) and other markers in the vicinity of the GLC1A gene on chromosome 1q. Screening of the TIGR gene identified a mutation that results in substitution of asparagine for isoleucine at codon 477 near the carboxyterminal end of the protein. CONCLUSIONS: The authors' findings strongly suggest that the juvenile-onset POAG locus in this family is the GLC1A locus and that the underlying cause of the disease is the IIe477Asn TIGR mutation that cosegregates with juvenile-onset POAG in one branch of this large family. Lack of samples from deceased individuals prevented the authors from determining whether reported adult-onset cases in this family could also be attributed to the IIe477Asn TIGR mutation. Absence of the IIe477Asn TIGR mutation from other juvenile- and adult-onset POAG families implies that this TIGR mutation is not a common cause of glaucoma.

Adolescent↗
PubMed1998

Ultrasound biomicroscopic localization and evaluation of intraocular foreign bodies.

PURPOSE: To evaluate the ultrasound biomicroscopic appearance of anterior segment foreign bodies under clinical and experimental conditions. METHODS: Ultrasound biomicroscopy was performed on 4 eyes of 4 patients referred for evaluation of anterior segment trauma and known or suspected intraocular foreign body. Imaging of wood, aluminum, concrete, and glass foreign bodies was performed in the anterior chamber of a human cadaver eye. RESULTS: Ultrasound biomicroscopy verified the location of a foreign body in two patients and identified occult foreign bodies in two others. Under clinical and experimental conditions, intraocular aluminum and glass produced comet tail artifacts. Under experimental conditions intraocular wood and concrete produced shadowing artifacts. CONCLUSION: Ultrasound biomicroscopy provides useful information in the evaluation of known and occult anterior segment foreign bodies. Ultrasound patterns of shadowing and comet tail may help differentiate foreign body materials.

Adolescent↗
PubMed1998

[Family history of glaucoma and risk factors in pigmentary glaucoma. A new clinical study].

BACKGROUND: Whether a family history of glaucoma (FHG) in patients with pigmentary glaucoma (PG) is a prognostical indicator, is unknown. Therefore the aim of this study was to evaluate the influence of FHG on the severity of the disease in PG and pigment dispersion syndrome (PDS). Furthermore risk factors in PG and PDS were evaluated. METHODS: The findings of 207 patients with PG and PDS, who were able to give information about FHG, were evaluated (149 PG, 43 PDS with ocular hypertension (OH), 15 PDS without OH). RESULTS: Significance of FHG: FHG was found in 39.1%, and in one third of the patients more than one relative had the disease. FHG was found in PG not more frequent than in PDS. Pigmentary glaucomas in advanced stages of the disease did not have a higher incidence of FHG than patients in beginning stages. Out of 207 patients with PG and PDS 71% were male and 29% female (p < 0.001). In patients with FHG the share of men was 64.2% and not significantly different to the group without FHG with 75.4%. The sex distribution in parents and grandparents having a glaucomatous disease was 1:1. RISK FACTORS: The pf1p4nts with and without FHG in PDS with and without OH, PG, and within the different stages of visual field loss, showed no significant differences in risk factors, for example in maximum intraocular pressure, refraction and cup-disc ratio. Myopia: Patients with PG had a significantly higher myopia than patients with PDS (p < 0.01). The higher the myopia, the earlier the disease was diagnosed (p = 0.008). Krukenberg spindle: During miotic therapy the Krukenberg spindle decreased in the upper half of the cornea. Time of diagnosis: PG was diagnosed at a higher age compared to PDS. CONCLUSION: FHG does not influence the severity of the disease in PG. Family history of glaucoma is a risk factor in patients with PG, but no prognostical indicator. Patients with FHG do not have primarily larger cup-disc ratios than patients without FHG. Myopia is a risk factor.

Adolescent↗
PubMed1998

Peripapillary nerve fiber layer thickness measurement reproducibility using scanning laser polarimetry.

PURPOSE: The authors assess the reproducibility of retinal nerve fiber layer (RNFL) thickness measurements using scanning laser polarimetry. METHODS: The right eyes of five healthy individuals were scanned by two trained operators (S.T.H., H.I.) using the Nerve Fiber Analyzer II (Laser Diagnostic Technologies, Inc., San Diego, CA, U.S.A.). Each participant was scanned six consecutive times per session for five sessions carried out over separate days within a two-week period. Intra- and interoperator measurement reproducibility was assessed. RESULTS: Intraoperator reproducibility was high. Mean coefficients of variation for total RNFL thickness measurements were 4.48 +/- 1.76% and 4.92 +/- 2.32% for operators 1 and 2, respectively. Interoperator reproducibility was high (p = 0.20-0.93) if a single ellipse was applied to the images of both examiners. However, measurement reproducibility worsened if each operator created his own measurement ellipse (p < or = 0.05 for 3 out of 5 participants). CONCLUSION: Interoperator error in image analysis can be minimized by using a single ellipse for the baseline and all subsequent scans even if subsequent scans are acquired by different operators.

Adult↗
PubMed1998

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.

Adolescent↗
PubMed1998

Late hypotony after cataract extraction due to a scleral fistula: a technique for surgical correction.

The authors report the use of a surgical procedure for the correction of a scleral fistula in a patient with late hypotony after cataract surgery. Trephination of necrotic tissue lining the scleral fistula with a double scleral patch technique was performed. Four months later, the patient's vision had improved to 20/40, with improvement of the macular folds and an intraocular pressure of 10 mm Hg. The authors conclude that the use of a double-patching technique is effective in the repair of scleral fistulas. The technique allows one to avoid more risky repair procedures that involve a greater area of tissue excision.

Aged↗
PubMed1998

Reproducibility of retinal thickness measurements in normal eyes using optical coherence tomography.

BACKGROUND AND OBJECTIVE: To determine the reproducibility of retinal thickness measurements in normal eyes using optical coherence tomography (OCT). PATIENTS AND METHODS: Multiple 3.20-mm vertical cross-sectional images through the center of fixation of consecutive patients with normal results on ocular examinations were obtained. Each image was divided into seven 320-micron segments. Regional retinal thicknesses for each section were measured using both the manually assisted (requiring observer localization of reflectivity peaks) and the automated modes (observer-independent measurement) of the computer software. RESULTS: Eighteen right eyes were studied. The mean coefficient of variation was less than 10% for all locations using the manually assisted method (average standard deviation less than 17 microns [range 9 to 16 microns]). The automated method was less reliable, with a coefficient of variation greater than 10% for locations within 500 microns of fixation. Automated measurements at fixation were the least reproducible because of poor internal limiting membrane reflectivity. CONCLUSION: OCT is capable of reproducible measurement of retinal thickness in normal eyes. Computer-driven, automated measurement of retinal thickness within 500 microns of fixation needs to be refined and its reproducibility reassessed in this region.

Adult↗
PubMed1998

Factors affecting image acquisition during scanning laser polarimetry.

BACKGROUND AND OBJECTIVE: To illustrate artifacts that may be encountered during measurement of the peripapillary retinal nerve fiber layer (RNFL) using scanning laser polarimetry (SLP). PATIENTS AND METHODS: A total of 426 patients with a variety of ocular diagnoses underwent RNFL measurements using SLP from June 1996 to April 1997. Scanning was performed by two operators whose reproducibility of measurements had been previously validated. Images were selected to illustrate clinical features that adversely affected measurement of the thickness of the RNFL. RESULTS: Image acquisition was difficult in eyes with corneal grafts or edema, keratic precipitates, anterior uveitis, posterior subcapsular cataract, vitreous opacity, peripapillary atrophy, posterior staphyloma, and high axial myopia. These scans resulted in poor clinical correlation with visual field tests and optic nerve examination, poor reproducibility of images, and unreadable images. CONCLUSION: Anterior and posterior segment pathologies, particularly those localized to the cornea and lens, may produce spurious RNFL measurements and should be carefully considered prior to clinical decision making.

Aged↗
PubMed1997

Identification of a gene that causes primary open angle glaucoma.

Glaucoma is a major cause of blindness and is characterized by progressive degeneration of the optic nerve and is usually associated with elevated intraocular pressure. Analyses of sequence tagged site (STS) content and haplotype sharing between families affected with chromosome 1q-linked open angle glaucoma (GLC1A) were used to prioritize candidate genes for mutation screening. A gene encoding a trabecular meshwork protein (TIGR) mapped to the narrowest disease interval by STS content and radiation hybrid mapping. Thirteen glaucoma patients were found to have one of three mutations in this gene (3.9 percent of the population studied). One of these mutations was also found in a control individual (0.2 percent). Identification of these mutations will aid in early diagnosis, which is essential for optimal application of existing therapies.

Base Sequence↗
PubMed1997

Isolation and culture of iris pigment epithelium from iridectomy specimens of eyes with and without exfoliation syndrome.

OBJECTIVE: To culture iris pigment epithelium (IPE) from surgical iridectomy specimens of eyes with and without exfoliation syndrome. METHODS: The IPE was treated to obtain a single cell suspension. Cells were cultured in Ham F12 nutrient mixture, which was supplemented with 30% fetal bovine serum, 50-micrograms/mL [corrected] gentamicin, and 2-mmol/L glutamine. After confluence, the cells were detached using a 0.125% trypsin-0.01% edetic acid solution, resuspended, diluted, and subcultured. The IPE from primary cultures and subcultures was studied by transmission electron microscopy. Immunocytochemical staining was performed. RESULTS: In the primary cultures of IPE from patients with exfoliation syndrome, curved, cross-banded, fine fibrils (diameter, 10-15 nm; periodicity, 10-14 nm) were found on the cell surface. Thicker fibrils (diameter, 24-48 nm; periodicity, 24-36 nm) were found external to the fine fibrils. Subcultures contained mainly fine fibrils. The IPE cells stained positively with anticytokeratin, S100 protein, and vimentin antibodies. CONCLUSION: Iris pigment epithelium can be successfully cultured from eyes with exfoliation syndrome. Studying the production of exfoliation material in vitro should provide information about the pathogenesis of exfoliation syndrome and about the nature of the exfoliation material. The cultivation of normal IPE from surgical specimens provides a source for the study of the growth regulation and pharmacophysiology of IPE in vitro.

Adolescent↗