Clinical features distinguishing angle closure from pseudoplateau versus plateau iris.

PURPOSE: To evaluate clinical aspects of patients with the diagnosis of plateau iris (PI) or pseudoplateau iris (PPI) made by ultrasound biomicroscopy (UBM) in order to determine if there are any clinical factors that can help differentiate between these two entities. METHOD: A retrospective cohort of consecutive UBM patients with the diagnosis of PI or PPI. The diagnosis of PI was based on an anteriorly positioned ciliary body that abutted the peripheral iris, a narrow (<10 degrees) or closed angle for at least 180 degrees, and the anterior portion of the iris positioned anterior to scleral spur. The diagnosis of PPI was similar to plateau except that large or a cluster of small cysts had to be present in the iridociliary sulcus. RESULTS: There were a total of 76 patients (29% male), 21 with PPI and 55 with PI. Patients with PPI were more likely to be male (p = 0.005), slightly younger (51.5 (SD 10.7) vs 57.9 (10.2) p = 0.0190), have a "bumpy" peripheral iris appearance (p = 0.003), have greater trabecular meshwork pigmentation (2.0 (0.7) vs 1.3 (0.6) p = 0.004) and have fewer clock hours of gonioscopic angle closure versus plateau iris patients (5.1 (4.3) vs 9.2 (4.2) p = 0.0009). Spherical equivalent was not significantly different between groups (0.50D (1.69) PPI vs 1.33D (2.42) PI; p = 0.187). CONCLUSIONS: In patients being referred to a UBM clinic for evaluation of angle-closure mechanism, younger males with a bumpy peripheral iris have a higher likelihood of having a diagnosis of pseudoplateau iris. However, clinical factors do not appear to discriminate well between PPI and PI. UBM is extremely helpful in confirming underlying mechanism and guiding therapy.

Selective laser trabeculoplasty versus argon laser trabeculoplasty: results from a 1-year randomised clinical trial.

AIMS: To compare selective laser trabeculoplasty (SLT) and argon laser trabeculoplasty (ALT), in terms of intraocular pressure (IOP) lowering, in patients with open-angle glaucoma. METHODS: 176 eyes of 152 patients were enrolled in this study, 89 in the SLT and 87 in the ALT groups. Patients were randomised to receive either SLT or ALT treatment to 180 degrees of the trabecular meshwork. Patients were followed up to 12 months after treatment. The main outcome measured was IOP lowering at 12 months after treatment, compared between the SLT and ALT groups. RESULTS: No significant difference (p = 0.846) was found in mean decrease in IOP between the SLT (5.86 mm Hg) and ALT (6.04 mm Hg) groups at 1 year or at any other time points, nor were there any significant differences in the rate of early or late complications between the two groups. CONCLUSIONS: SLT is equivalent to ALT in terms of IOP lowering at 1 year, and is a safe and effective procedure for patients with open-angle glaucoma.

Baseline IOP predicts selective laser trabeculoplasty success at 1 year post-treatment: results from a randomised clinical trial.

BACKGROUND/AIMS: The efficacy and safety of selective laser trabeculoplasty (SLT) has been found to be equivalent to argon laser trabeculoplasty (ALT). Since SLT produces significantly less disturbance to the trabecular meshwork and is theoretically more repeatable than ALT, it has potential to replace ALT as the standard procedure to treat medically uncontrolled open angle glaucoma. This study's objective is to determine factors that predict successful SLT at 1 year post-treatment. METHODS: As part of a randomised clinical trial comparing the efficacy and safety of SLT to ALT, data on 72 SLT patients were collected, and successful SLT defined as having an SLT induced intraocular pressure (IOP) reduction of >or=20% at 1 year post-treatment follow up. RESULTS: 43 out of the 72 patients who had completed their 1 year follow up visit had an IOP reduction of >or=20% from baseline. No glaucoma risk factors studied predicted successful SLT. The amount of trabecular meshwork pigmentation was not a significant predictor. However, it was discovered that baseline IOP strongly predicted SLT success (odds ratio=1.16; p=0.0001). CONCLUSION: SLT success was significantly predicted by baseline IOP but not by age, sex, other glaucoma risk factors, type of open angle glaucoma, or by degree of trabecular meshwork pigmentation.

Trichiasis and disability in a trachoma-endemic area of Tanzania.

OBJECTIVE: To measure limitations in the daily activities of village life associated with having trichiasis for individuals with and without visual acuity loss. METHODS: Men and women 40 years and older in 6 randomly chosen rural villages in the Kongwa district of Tanzania had visual acuity measured and were examined by an ophthalmologist. Subjects indicated the degree of difficulty with daily activities of village life and whether the difficulty was related, in any way, to vision. Limitations were scored using an indicator of "any difficulty" and using a 4-point scale ranging from "no difficulty" to "unable to do." Scores of individuals with and without trichiasis were compared separately for men and women. RESULTS: Among men, trichiasis was associated with excess functional limitation only for those with visual acuity loss (adjusted difference in proportion of tasks [AD] compared with men with neither trichiasis nor visual impairment, 0.35; 95% confidence interval [CI], 0.23-0.47). For women, trichiasis alone was limiting (AD, 0.15; 95% CI, 0.08-0.22) similarly to visual acuity loss alone (AD, 0.09; 95% CI 0.06-0.13), and the combination led to greater limitations (AD, 0.32; 95% CI, 0.26-0.39). CONCLUSION: The burden of trichiasis is likely greater than previously estimated, especially in women for whom trichiasis alone was disabling.

Prevalence of the different types of age-related cataract in an African population.

PURPOSE: To describe the prevalence of different types of cataract and their association with visual acuity in a Tanzanian population aged 40 years and older. METHODS: A prevalence survey for lens opacity, glaucoma, and visual impairment was carried out on all residents age 40 and older of six villages in Kongwa, Tanzania. One examiner graded the lens for presence of nuclear (NSC), posterior subcapsular (PSC), and cortical cataract (CC), using the new WHO Simplified Cataract Grading System. Visual acuity was measured in each eye, both presenting and best corrected, using an illiterate E chart. RESULTS: The proportion of eligible subjects participating was 90% (3268/3641). The prevalence of cataract was as follows: NSC, 15.6%; CC, 8.8%; and PSC, 1.9%. All types of cataract increased with age, from NSC, 1.7%; CC, 2.4%; and PSC, 0.4% for those aged 40 to 49 years to NSC, 59.2%; CC, 23.5%; and PSC, 5.9% for those aged 70 years and older (P < 0.0001 for all cataract types, chi(2) test for trend). Cataract prevalence was higher among women than men for NSC (P = 0.0001), but not for CC (P = 0.15) or PSC (P = 0.25), after adjusting for age. Prevalence rates of visual impairment (BCVA < 6/12), US blindness (< or = 6/60) and WHO blindness (< 6/120) for this population were 13.3%, 2.1%, and 1.3%, respectively. Older age and each of the major types of pure and mixed cataract were independently associated with worse vision in regression modeling. CONCLUSIONS: Unlike African-derived populations in Salisbury and Barbados, NSC rather than CC was most prevalent in this African population. The seeming lower prevalence of CC may to some extent be explained by different grading schemes, differential availability of cataract surgery, the younger mean age of the Tanzanian subjects, and a higher prevalence of NSC in this population.

An inventory of information on blindness and visual impairment in Canada.

BACKGROUND: Several health databases contain information on blindness and visual impairment in Canada. Such databases may permit studies of the outcomes, predictors, economic costs and meta-analysis of ocular health problems and visual disability. In this paper we summarize the existing public health information on blindness and visual impairment in Canada. METHODS: A systematic search was performed to find the information in three areas: health administrative databases, health surveys and registries. Both literature searching and Internet searching were performed. The institutions were notified by email or telephone that information pertaining to vision and blindness was desired. When necessary, we visited the institution to obtain the information. RESULTS: Health administrative databases contain information on a wide cross-section of diagnoses but are usually limited in detail and seldom provide longitudinal information. Health surveys have a limited amount of systematic information on vision-related questions and rely exclusively on self-reporting. Registries exist on a wide range of visual topics. The Canadian National Institute for the Blind (CNIB) has the most comprehensive registry. INTERPRETATION: This is the first attempt at summarizing all the public health information on blindness and visual impairment in Canada. The present population-based ocular information has numerous shortcomings. More comprehensive validation of large registries, such as that of the CNIB, is needed to provide the foundation for a longitudinal ocular surveillance system. Such a system could guide research on risk factors and the effect of treatment, economic analyses, and public policy for ocular research and service allocation.

Long term results of glaucoma surgery among participants in an east African population survey.

AIM: To evaluate the long term results of glaucoma surgery among people in East Africa. METHODS: Participants in a population based survey of eye disease prevalence were offered glaucoma surgery using standardised criteria. Either surgical iridectomy or trabeculectomy was carried out as indicated by a medical officer or by one of two ophthalmologists. Trabeculectomy methods included releasable sutures and mitomycin C in the majority of eyes. Subjects were examined during the first week and 2 months after surgery. Nearly 3 years later, re-examination was carried out in those who were still resident in the region. RESULTS: Among 46 people who were offered iridectomy, trabeculectomy, or combined cataract extraction/lens implant/trabeculectomy, 21 people underwent surgery (46%). Of the 21, 19 were re-examined at 3 years (90%), including 16/18 eyes after trabeculectomy. Among these, intraocular pressure (IOP) declined from 29.9 (SD 9.4) mm Hg to 14.7 (5.9) mm Hg, with 16 of 18 eyes (89%) achieving a reduction > 25%. Hypotony maculopathy, late bleb leak, and late endophthalmitis were not detected. Visually significant cataract developed in 5/15 re-examined eyes that underwent trabeculectomy alone (33%), possibly associated with pre-existing cataract and diagnosis of angle closure glaucoma, but not with mitomycin C use. CONCLUSIONS: Nearly half of those with glaucoma among residents of rural African villages accepted the offer of surgical therapy. While technical success was achieved at satisfactory levels, the development of cataract must be considered an important issue for application of glaucoma surgical therapy programmes.

Prevalence of glaucoma in a rural East African population.

PURPOSE: To determine the prevalence of glaucoma in an adult population in rural central Tanzania. METHODS: Six villages were randomly selected from eligible villages in the Kongwa district, and all residents more than 40 years of age were enumerated and invited to a comprehensive eye examination including presenting visual acuity, refraction, automated 40-point Dicon (San Diego, CA) suprathreshold screening field test, Tono-Pen (Bio-Rad, Inc., Boston, MA) intraocular pressure (IOP) measurement, and standardized examination by an ophthalmologist of anterior segment, optic nerve head, and retina after pupil dilation. Gonioscopy and Glaucoma-Scope (Ophthalmic Imaging Systems, Sacramento, CA) optic disc imaging were performed on those with IOP higher than 23 mm Hg and cup-to-disc ratio (c/d) more than 0.6 and on a 20% random sample of participants. RESULTS: Of 3641 eligible persons, 3268 (90%) underwent ophthalmic examination. The prevalence of glaucoma of all types was 4.16% (95% confidence interval [CI] = 3.5, 4.9%). Primary open-angle glaucoma (OAG) was diagnosed in 3.1% (95% CI = 2.5, 3.8%), primary angle-closure glaucoma (ACG) in 0.59% (95% CI = 0.35, 0.91%), and other forms of glaucoma in 0.49%. The prevalence of glaucoma was found to be sensitive to changes in the diagnostic criteria. CONCLUSIONS: The high prevalence of OAG in this group was similar to that of African-derived persons in the United States but less than in African-Caribbean populations. ACG was more prevalent in east Africans than suggested by anecdotal reports.

Multicentric epithelioid angiosarcoma of the bone. Pitfalls in clinical and morphological diagnosis.

Epithelioid angiosarcoma of the bone represents a challenging diagnosis by bone marrow biopsy. We present a case of a multicentric high grade angiosarcoma of the bone with epithelioid features. On the basis of the clinical presentation, the radiological findings, and the appearance of loosely clustered tumor cells detected in the initial bone marrow biopsy, the main differential diagnoses considered were a poorly differentiated non-secretory multiple myeloma and metastatic carcinoma. Subsequent morphologic, immunohistochemical and electron microscopic examination of tissue samples clarified the nature of the tumor as epithelioid angiosarcoma. We discuss potential pitfalls in clinical and morphological diagnosis. The strong reactivity of the tumor cells with the nonspecific but ubiquitous mesenchymal marker vimentin in similar cases should direct early attention to the rare malignant bone tumor, epithelioid angiosarcoma, with subsequent confirmation of this diagnosis with specific immunohistochemical endothelial cell markers and/or electron microscopy.