Search PubMed⌕ Search

Biomedical subjects

T Zeyen

Publications and source records attributed to T Zeyen.

At least 37 records · Page 2Linked to original sources
PubMed1999

Target pressures in glaucoma.

Despite exciting progress in the field of neuro-protection, lowering the intraocular pressure is still the only available option to treat glaucoma patients. The level to which the intraocular pressure should be lowered is different for each individual patient. The formula proposed to calculate the "target pressure" takes into account the pressure at which the glaucomatous damage presumably occurred (the "maximum pressure") and the risk of future damage. This target pressure should be re-evaluated periodically.

Aging↗
PubMed1999

Comparison of the effect of Healon vs. Viscoat on endothelial cell count after phacoemulsification and posterior chamber lens implantation.

To evaluate the protective effect of 1% sodium hyaluronate (Healon) vs. a mixture of 4% chondroitin sulfate and 3% sodium hyaluronate (Viscoat) on the central corneal endothelium during surgery, we prospectively examined 20 eyes of 20 patients who underwent clear corneal phacoemulsification and implantation of an intracapsular posterior chamber intraocular lens (PC-IOL) with either Healon (10 eyes) or a combined use of Viscoat and Healon (10 eyes) as viscoelastic material. We compared the central endothelial cell counts, recorded by specular microscopy, preoperatively and 6 weeks postoperatively. Our results suggest that Viscoat offers no significant better endothelial cell protection during phacoemulsification than Healon.

Adult↗
PubMed1998

Management of a cracked Acrysof intraocular lens during implantation. Case report.

The importance of a sufficiently large incision during soft intraocular lens (IOL) implantation is illustrated and highlighted by a single case study. In our patient, insufficient enlargement of the incision caused a crack in the optic of the Acrysof IOL. The IOL could, however, be left in place because of its excellent biocompatibility. Different management options are discussed.

Humans↗
PubMed1998

Conventional retinal detachment surgery: technique, complications and results.

A uniform conventional technique, modified by Dr. Zivojnovic, was performed on 104 consecutive patients with rhegmatogenous retinal detachments including pseudophakic eyes (23.1%) and cases with preoperative proliferative vitreoretinopathy (PVR) A-C2 (21.2%). A prospective study of 59 variables in 104 cases shows the risk factors influencing the results after a minimum follow-up (F.U.) according to multivariate analysis: preoperative detached macula, vitreous loss during previous cataract surgery and duration of detachment. The anatomic (94.2% reattachment after external surgery) and functional results (69.2% V.A. > or = 0.5) are discussed as well as the complications.

Cataract Extraction↗
PubMed1998

Costsaving in the operating room: the Procedure Pack.

The concept of the Procedure Pack is very relevant in this era of managed care. By collecting more items in one pack, the hidden costs will be reduced and the pack will become relatively cheaper than the sum of every item. This paper compares the price of the Procedure Pack with the price of the separate items used for routine phaco-emulsification. The Procedure Pack is 2% more expensive, but the benefits by reducing the hidden costs are substantial and will be analyzed.

Belgium↗
PubMed1998

Diode laser cyclophotocoagulation in refractory glaucoma.

A retrospective analysis was made of the first 19 eyes of 19 patients with intractable glaucoma treated with contact diode cyclophotocoagulation. We assessed intraocular pressure (IOP) and number of glaucoma medications. The mean follow-up was 4 months (range 1 to 11 months). Mean IOP's decreased from 31.7 +/- 14.6 pre-diode treatment to 23.7 +/- 16.9 mmHg at the last follow-up visit after treatment (p = 0.02). The mean number of medications required decreased from 1.9 before to 1.3 after treatment (p = 0.03). The study suggests that diode cyclophotocoagulation is an effective and safe procedure in eyes with refractory glaucoma.

Adult↗
PubMed1997

Interpretation of automated perimetry.

This paper discusses basic principles of visual field interpretation. Only the two most popular perimeters, the Octopus and the Humphrey Field Analyzer, were considered. Choices of tests and strategies, software to assist interpretation (with emphasis on glaucoma progression), and future trends in visual field testing are covered.

Automation↗
PubMed1996

Comparison of methods to evaluate the optic nerve head and nerve fiber layer for glaucomatous change.

PURPOSE: To compare the rates of optic nerve damage in early human glaucoma as measured by four methods to evaluate change in the optic nerve and nerve fiber layer. METHODS: Four techniques were used to detect progressive glaucomatous damage in a prospective, longitudinal study: (1) qualitative evaluation of stereoscopic color optic disk photographs, (2) qualitative evaluation of monochromatic nerve fiber layer photographs, (3) manual stereoplanimetric measurements of disk rim area, and (4) computerized measurement of peripapillary nerve fiber layer height. One eye of each patient with glaucoma or ocular hypertension was evaluated at the beginning and end of a follow-up period of not less than one year. The rates of structural change measured by these techniques and the rate of visual field change measured with threshold automated perimetry were determined. RESULTS: We followed up 193 patients for a mean (+/- S.D.) of 3.3 +/- 1.0 years (range, one to six years). Twenty-nine (15%) of 193 eyes progressed by qualitative optic disk evaluation, 14 (7.2%) of 193 eyes progressed by qualitative nerve fiber layer evaluation, seven (3.6%) of 193 eyes progressed by stereoplanimetry, and 24 (13.2%) of 182 eyes progressed by measurement of nerve fiber layer height. Visual field deterioration was detected in 12 (5.2%) of 193 patients and correlated best with qualitative optic disk and nerve fiber layer evaluations. Evaluation by stereoplanimetry and nerve fiber layer height measurement detected change in eyes with primarily diffuse structural damage, a pattern not well detected by qualitative methods. CONCLUSION: Both qualitative and quantitative methods of optic disk and nerve fiber layer evaluation contribute to the identification of progressive damage, depending on the stage of disease and the characteristics of optic nerve cupping.

Aged↗
PubMed1995

Reliability of the Nidek NT-1000 non contact tonometer.

In this prospective study, we compared the intraocular pressure (IOP) readings of 100 patients measured with the Goldmann applanation tonometer and the Nidek NT-1000 pneumotonometer. The correlation coefficient between the Goldmann and Nidek readings was 0.86. On the average the pneumotonometer overestimated the intraocular pressure with 0.43 mm Hg. The Nidek NT-1000 non contact tonometer can be used for screening purposes provided an appropriately low IOP value is used to indicate the need for further assessment with the Goldman applanation tonometer.

Adult↗
PubMed1994

Treatment of traumatic optic neuropathy, a case report.

We report a case of post-traumatic optic neuropathy in which visual improvement, documented with visual evoked potentials (VEP), occurred after administration of a corticoid megadose. The presentation of a single case does not allow to extrapolate conclusions about the efficacy of the steroid treatment, but serves as an illustration for a controversial problem as the management of post-traumatic optic neuropathy.

Adult↗
PubMed1993

An evaluation of clusters in the glaucomatous visual field.

We used a statistical cluster analysis to analyze patterns of loss in 76 visual fields with typical glaucomatous defects to identify natural groupings of test locations in the visual field. Eleven clusters in the Octopus Program G1 (Interzeag, Inc., Northboro, Massachusetts) visual field were thus defined. In a separate population of 70 early glaucomatous and 70 age-matched normal visual fields, the local mean defects within these clusters and the global mean defect were calculated to assess their relative abilities to discriminate between the two groups. The 11 clustered mean defects collectively had a sensitivity of 90% and a specificity of 93%; the global mean defect had a sensitivity of 81% and a specificity of 91%. Additionally, we examined the long-term fluctuation clusters of test locations compared to the long-term fluctuation of individual test locations. Four hundred ten visual fields of 93 clinically stable eyes of 67 patients with glaucoma, as well as 210 visual fields of 105 eyes of 105 normal subjects were studied. In the stable glaucoma group, mean fluctuation of clustered test locations was 3.5 dB2, and mean fluctuation of individual test locations was 7.0 dB2. In the normal group, the respective values were 0.6 dB2 and 1.8 dB2. Cluster analysis was effective in detecting localized loss and in dampening long-term fluctuation. We studied the use of clusters in distinguishing normal from glaucomatous as well as stable from deteriorating visual fields.

Adult↗
PubMed1993

Wolfram syndrome: a clinical study of two cases.

Two unrelated patients with two different images of Wolfram (or 'DIDMOAD') syndrome are presented: a 19-year old woman suffering from all the important features of this syndrome, and a 38-year old man showing two major characteristics but several minor abnormalities. This syndrome should be considered in young diabetic patients with unexplained visual loss or with polyuria and polydipsia in the presence of adequate blood sugar control. An early diagnosis is important to prevent unnecessary diagnostic investigations.

Adult↗
PubMed1993

Comparisons of methods to detect glaucomatous optic nerve damage.

PURPOSE: Various techniques of optic disc and nerve fiber layer evaluation may be used to detect structural glaucomatous damage. The authors compared several qualitative and quantitative methods to determine their relative sensitivities and specificities to detect the presence of glaucomatous visual field loss. METHODS: Fifty-one healthy eyes, 169 ocular hypertensive eyes with normal visual fields, and 132 glaucomatous eyes with early visual field defects were evaluated with qualitative and quantitative measures of structural damage to the optic nerve and nerve fiber layer. Qualitative evaluations were performed by three experienced masked observers who independently graded stereoscopic color disc and monochromatic nerve fiber layer photographs. Quantitative measurements of disc rim area and nerve fiber layer height were made with digitized image analysis of videographic images. Manual planimetric measurements of disc rim area were made from enlarged prints of stereoscopic optic disc photographs. Diagnostic precision was defined as the total proportion of correct diagnoses for the presence or absence of visual field loss. RESULTS: The diagnostic precision of results of a quantitative disc examination (81%) was greater than those of a qualitative nerve fiber layer examination (75%). Quantitative nerve fiber height measurement had the highest sensitivity rate (73%) and results of the qualitative disc examination had the highest specificity rate (87%) of the methods tested. CONCLUSION: The diagnostic precision of disc evaluation was superior to other methods, including nerve fiber layer examination, in correctly determining the presence of structural glaucomatous damage at the early visual field loss stage.

Adult↗
PubMed1993

How useful are scrapings in the treatment of corneal ulcers?

We retrospectively reviewed the records of patients, hospitalised in our department from january 1989 through january 1993, with the diagnosis of corneal ulcer. The medical records were analyzed and the information computed, with emphasis on the modalities of prelevation, and the response to treatment. Direct inoculation of scrapings on media and an initial treatment with a combination of fortified antibiotics have proven to be effective over the past several years.

Adolescent↗
PubMed1993

Fungal endophthalmitis: a report of two cases.

Two patients with fungal endophthalmitis are presented. The first patient developed delayed-onset pseudophakic endophthalmitis. Candida glabrata was cultured from anterior chamber fluid. The second patient presented with a corneal ulcer and endophthalmitis. Candida albicans was isolated from the corneal scraping. The clinical features of these infections and specific treatment options are discussed.

Adult↗
PubMed1992

Blindness following paranasal sinus surgery: a report of two cases.

Two cases of blindness following paranasal sinus surgery are presented. The first patient, a 38-year old man, developed a delayed massive haemorrhage, after bilateral sphenoethmoidectomy. This hemorrhage could be stopped by electric cauterisation under endoscopical control. During this reintervention the patient developed total blindness of his right eye, and a restriction of the inferotemporal left visual field. The second patient, a 10-year old girl, developed, after bilateral spheno-ethmoidectomy for isolated sphenoiditis, total blindness of the left eye and paralysis of the ipsilateral extraocular muscles. According to the literature, blindness secondary to paranasal surgery is mainly due to retrobulbar hemorrhage. In the first case blindness was due to a direct cauterisation of the optic nerve, after perforation of the lamina papyracea. In the second case, blindness was probably due to a hemorrhage in the orbital apex.

Adult↗