Biomedical subjects

B Roesen

Publications and source records attributed to B Roesen.

5 recordsLinked to original sources

PubMed2000

Central corneal thickness determined with optical coherence tomography in various types of glaucoma.

AIMS: To evaluate central corneal thickness determined by optical coherence tomography (OCT) in various types of glaucoma, and its influence on intraocular pressure (IOP) measurement. METHODS: Central corneal thickness (CCT) was determined by using OCT in 167 subjects (167 eyes). 20 had primary open angle glaucoma (POAG), 42 had low tension glaucoma (LTG), 22 had ocular hypertension (OHT), 10 had primary angle closure glaucoma (AC), 24 had pseudoexfoliation glaucoma (PEX), 13 had pigmentary glaucoma (PIG), and 36 were normal. RESULTS: CCT was significantly higher in ocular hypertensive subjects (593 (SD 35) microm, p <0.0001) than in the controls (530 (32) microm), whereas patients with LTG (482 (28) microm, p < 0. 0001), PEX (493 (33) microm, p <0.0001), and POAG (512 (30) microm, p <0.05) showed significantly lower readings. There was no statistically significant difference between the controls and patients with PIG (510 (39) microm) and AC (539 (37) microm). CONCLUSIONS: Because of thinner CCT in patients with LTG, PEX, and POAG this may result in underestimation of IOP, whereas thicker corneas may lead to an overestimation of IOP in subjects with OH. By determining CCT with OCT, a new and precise technique to measure CCT, this study emphasises the need for a combined measurement of IOP and CCT in order to obtain exact IOP readings.

Aged↗

PubMed1999

[Secondary glaucoma in Paraguay. Etiology and incidence].

Glaucoma is the third-most-frequent cause of blindness in the world, with a total of 5.2 million blind people as a result of this disease; 80% live in developing countries. In Paraguay, after cataract it is the second-most-frequent-cause. Early detection of the risk factors and groups can help to avoid progress of this disease. Trauma, cataract and infectious uveitis represent special risks for developing secondary glaucoma, which is a more frequent cause of blindness in third-world countries than in industrialized nations. Until now there has been little data regarding the causes, disease course, and options for therapy. Therefore, secondary glaucoma was examined in Paraguay to obtain information on the situation in Latin America. The aim of the study was to explore the causes of secondary glaucoma for programs concerning prevention and therapy. From November 1996 to February 1997 patients with secondary glaucoma were examined at the University Hospital of Asunción, Paraguay. After the clinical examination the secondary glaucomas were classified. Patients with primary glaucoma were included in the same period of time as well in order to get the rate of secondary glaucoma. Altogether 293 patients were examined: 61 with secondary and 232 with primary glaucoma. The causes of secondary glaucoma in 73 eyes were: 20 (27%) with pseudoexfoliation glaucoma, 19 (26%) with post-traumatic glaucoma, 16 (22%) with neovascular glaucoma, 4 (5%) with lens-related glaucoma, 3 (4%) with glaucoma associated with ocular surgery, 2 (3%) with pigmentary and 2 (3%) with corticoid-induced glaucoma. A ratio of 4:1 primary glaucomas to secondary glaucomas was found. The development of special measures for prevention and early therapy is only possible if the causes of this severe disease are explored. The results of this study represent basic information and could help to introduce of prevention programs.

Adolescent↗

PubMed1998

[Choroid neovascularization in senile macular degeneration. 1 hear follow-up after radiotherapy].

UNLABELLED: Choroidal neovascularization (CNV) associated with age-related macular degeneration is the major cause of legal blindness in Europe and the USA in patients aged more than 65 years, but Chakravarthy et al. has reported that radiotherapy has a beneficial effect on visual acuity. METHODS: Since March 1996 we have treated 56 patients in cooperation with the Department of Radiotherapy at the Technical University in Munich. The total dose with external beam radiotherapy was 16 Gy in 8 fractions, delivered through an anterior oblique axis to spare the lens. Before the treatment and 3, 6 and 12 months after therapy, we performed a standardized visual acuity and contrast-sensitivity test (ETDRS, Pelli Robson Chard) and fluorescin angiography 6 and 12 months after therapy. RESULTS: Twenty-five angiograms showed well-defined CNV and 31 not well-defined CNV. Six months after the treatment 15 patients had stable visual acuity within one line. Twenty-seven patients had lost more than one line of visual acuity. There was no difference between well and not well defined CNV's. One year after treatment the visual acuity remained stable within one line in 4 patients, no patient had an increase of two lines or more and 17 patients lost more then 2 lines of vision. We saw no side effects other than sicca symptoms in 3 patients. CONCLUSION: In our opinion, these results do not show that radiation treatment has a real beneficial effect on visual acuity. Further randomized studies are needed to demonstrate the efficiency of this treatment for choroidal neovascularization in AMD.

Aged↗

PubMed1995

[Perimetry with a glaucoma-specific test grid. A clinical study with the GG program].

UNLABELLED: The GG program pattern of the Humphrey Field Analyzer includes the 76 test points of the 30-2 program and an additional 52 test points in a glaucoma-specific distribution. In 18 test points in the nasal step area beyond 30 degrees the threshold is also determined. The findings obtained with the GG program and the 30-2 program were investigated by means of three questions: (1) Do the additional test points increase the sensitivity in ocular hypertension and glaucoma in stage I? For this purpose 41 eyes of 41 patients were examined. (2) Is the new grid useful for the determination of form and size of scotomas? For this purpose 46 eyes of 46 patients were examined. (3) What information is gained from a new asymmetry index, the glaucoma hemifield index (GHI), evaluated on the retinal threshold sensitivity of the GG program grid? To evaluate the information gained, the GHI of the test points in program 30-2 was compared to the GHI of the GG program in 11 eyes of 11 healthy persons, 21 eyes of 21 patients with ocular hypertension, and 32 eyes of 32 patients with primary open-angle glaucoma, stage I and II. RESULTS: (1) In ocular hypertension and glaucoma stage I, the higher grid density of the GG program leads to a higher sensitivity in comparison to program 30-2. (2) In the 46 eyes with scotomas in stages II-IV, the condensed grid allowed better assessment of form and size of them. Ninety-one percent of the eyes with glaucoma stage II-IV showed nasal scotomas out of 30 degrees excentricity, which were now detected with the GG program. (3) The GHI of program 30-2 and the GG program showed no significant difference in retinal threshold sensitivity in glaucoma stage I. The asymmetry of the visual field loss in glaucoma stage II with localized scotomas can be detected significantly better with the GHI of the GG program. At the beginning of visual field loss with diffuse sensitivity loss, the grid density of program 30-2 seems to be sufficient. In stage II with localized scotomas, the higher grid density of the GG program yield more information for the detection of hemifield asymmetries. After examination with the 30-2 program it seems to be useful to examine the 52 additional test points and combine these two with the print-out from the GG program.

Adult↗

PubMed1991

[Sensitivity of noise field campimetry as a screening method for glaucoma].

The glaucoma patient can perceive his or her visual field loss subjectively with snow field campimetry with the Tübingen electronic campimeter (TEC). The sensitivity of this new method of examination for glaucoma has not previously been evaluated. We were interested in finding whether absolute and relative scotomas could be detected with such high probability that snow field campimetry could be used as a screening method for the early detection of glaucoma. Analysis of the severity of scotoma is not possible, so that snow field perimetry can indeed by regarded as a screening procedure. A total of 76 eyes of 76 patients with glaucoma and stage I-IV visual field loss and 20 eyes of 20 patients with ocular hypertension were examined with threshold determining static perimetry (Octopus or Humphrey perimeter) and with the snow field of the TEC in controlled conditions. A qualitative comparison was drawn to evaluate how often a pathologic or normal finding was confirmed by snow field campimetry: of the 76 eyes affected by scotoma, 65 eyes (85.5%) showed pathologic findings consistent with the result of snow field campimetry, and 11 eyes showed normal findings. The visual field loss was 63.6% for glaucomatous visual field loss stage I: 90.9% for glaucomatous visual field loss stage II, and 95% for visual field loss stages III and IV. For 16 of the 20 eyes with ocular hypertensions normal findings were reported with snow field campimetry. Snow field campimetry is suitable for use as a quick screening procedure, but only for absolute glaucomatous scotomas.

Adult↗