PubMed Health⌕ Search

Biomedical subjects

S C Gieser

Publications and source records attributed to S C Gieser.

15 recordsLinked to original sources
PubMed1996

Blindness and visual impairment in western Bulgaria.

The Sofia Eye Survey was a population-based blindness and visual impairment survey of 6,275 randomly selected men and women from the Sofia district and Sofia city in western Bulgaria. A complete house-to-house census on all adults over age 40 years was performed, and visual acuity performed on 98%. We referred 171 subjects for a complete dilated ophthalmologic examination because the pinhole vision in the better eye was 6/18 or worse. Trained ophthalmologists refracted all referred subjects and then examined them with a slit lamp and ophthalmoscopy to determine the cause of visual loss. The rate of blindness (defined as vision in the better eye worse than 3/60) in this population was 0.49% and the rate of visual impairment (6/18 to 3/60 in the better eye) was 0.83%. The leading cause of both blindness and visual impairment was cataract. These data from the first community-based survey of blindness in Eastern Europe suggest that the rates of blindness and visual impairment are similar to those reported from other developed countries.

Adult↗
PubMed1995

Molteno implant surgery for advanced glaucoma.

PURPOSE: The use of adjunctive antimitotics with conventional filtering surgery appears to have decreased the need for Molteno implants in glaucomas with a poor prognosis. We review the current status, results and complications of Molteno implants. METHODS: Review of the literature and practical experience from two university departments of ophthalmology. RESULTS: Improvements in the design and surgical techniques for Molteno implants have decreased the incidence of over filtration, but this and other complications continue to pose problems. Increased success rates may be possible if antimitotics are used with Molteno implants. CONCLUSION: Molteno implants continue to be an option when conventional filtration with or without antimitotics has failed; they continue to be regarded as a last resort for filtration. The use of antimitotics to increase the success rate of Molteno implants is not proven, but merits further investigation.

Conjunctiva↗
PubMed1994

Synthesis of the literature on visual acuity and complications following cataract extraction with intraocular lens implantation. Cataract Patient Outcome Research Team.

OBJECTIVE: To better define the effectiveness and risks of modern cataract surgery. DESIGN: Meta-analysis (formal systematic identification, selection, review, and synthesis) of published literature. PATIENTS: Patients described in 90 studies published between 1979 and 1991 that addressed visual acuity (n = 17,390 eyes) or complications (n = 68,316 eyes) following standard extracapsular cataract extraction with posterior chamber intraocular lens implantation, phaco-emulsification with posterior chamber intraocular lens implantation, or intracapsular cataract extraction with flexible anterior chamber intraocular lens implantation. MAIN OUTCOME MEASURES: The proportion of eyes with postoperative Snellen visual acuity of 20/40 or better and the proportion of eyes with each of 18 complications. RESULTS: The pooled percentage of eyes (weighted by sample size) with postoperative visual acuity of 20/40 or better was 95.5% (95% confidence interval [CI], 95.1% to 95.9%) among eyes without preexisting ocular comorbidity and 89.7% (95% CI, 89.3% to 90.2%) for all eyes. The pooled percentage of eyes experiencing complications (weighted by sample size and, when pertinent, by quality score of the individual studies but not adjusted for variation in duration of follow-up) ranged from 0.13% for endophthalmitis to 19.7% for posterior capsule opacification. Pooled proportions of eyes with other complications were as follows: bullous keratopathy, 0.3%; intraocular lens malposition/dislocation, 1.1%; clinically apparent cystoid macular edema, 1.5%; and retinal detachment, 0.7%. Pooled results for postoperative Snellen visual acuity and most complications were similar for surgery performed via phacoemulsification vs standard extracapsular cataract extraction, although comparisons of the outcomes between these procedures should be interpreted with caution. CONCLUSIONS: The published literature indicates that modern cataract surgery yields excellent visual acuity and, although not free of complications, is a very safe procedure regardless of the extraction technique used.

Aged↗
PubMed1994

Ophthalmology in Bulgaria.

Bulgaria faces a marked shortage of ophthalmic resources. There are over 600 ophthalmologists for this Balkan nation of 8.9 million, giving Bulgaria a ratio of ophthalmologists to overall population that is similar to that of the United States; however, less than 20% of these ophthalmologists perform surgery. No formal residency or fellowship training programs exist in the country. Ophthalmic textbooks and journals are written predominantly in Russian and are in short supply. Pharmaceutical supplies are extremely limited. The leading cause of blindness in Bulgaria is cataracts that have not been treated surgically. Most cataracts are removed with intracapsular extraction. However, in the major cities, extracapsular cataract extraction with implantation of intraocular lenses is available.

Blindness↗
PubMed1993

Incidence of complications following 5-fluorouracil with trabeculectomies.

To investigate the incidence of complications reportedly caused by the use of 5-fluorouracil (5-FU) in glaucoma filtering surgery, we performed trabeculectomy with 5-FU on 57 eyes of 56 patients with advanced glaucoma. The mean preoperative intraocular pressure was 34.8 mm Hg. The most frequent complication encountered was superficial punctate keratopathy (26%), followed by shallowing of the anterior chamber (12%), choroidal detachment (9%), and flap retraction (7%). We, however, did not encounter any cases of confluent corneal epithelial defect, subepithelial scarring, or striate melanokeratosis which are usually described with the use of 5-FU. With a mean follow-up of 7.1 months, an intraocular pressure less than 16 mm Hg without hypotensive therapy were achieved in 73.7% of cases, and less than 21 mm Hg without hypotensive therapy in 86%. Considering the low incidence of complications and the high success rate, we recommend the use of 5-FU in routine glaucoma filtering surgery.

Combined Modality Therapy↗
PubMed1993

Releasable suture technique for trabeculectomy.

We studied the effect of the releasable suture technique on immediate postoperative intraocular pressure (IOP). Nine eyes of nine patients with glaucoma had trabeculectomy with a releasable suture. In the six eyes that did not receive antimitotics, the suture was released by the fifth postoperative day; in the others suture release was delayed up to the fourteenth day. Of the nine patients, one had an acceptable postoperative IOP and did not need suture release; in another the suture broke and could not be released. In the remaining seven patients, the difference between the pre-release and post-release IOP was statistically significant (p < 0.001). The complications of this technique include failed suture release, subconjunctival hematoma and a distinctive "windshield wiper" keratopathy.

Corneal Diseases↗
PubMed1991

Assessment of potential contrast sensitivity. Part I: Preoperative prediction of contrast sensitivity following intraocular lens implantation.

Preoperative contrast sensitivity functions (CSFs) were determined for 15 cataract patients using laser-generated patterns that effectively bypassed the optical components of the eye. These functions were compared with postoperative CSFs determined using traditional methods by transmission through the optics of the eye. Accurate prediction of postoperative contrast sensitivity occurred in 91% of the cases (ten of 11) for patients with preoperative visual acuity of 20/200 or better and in 67% of all the cases (ten of 15). Prediction failures occurred when the laser interferometer was not able to penetrate the cataract or when postoperative complications occurred. These results suggest that preoperative measurement of laser interferometric CSF is a useful predictor of postoperative CSF for patients with mild to moderate cataracts that can be bypassed by the laser and with better than 20/200 preoperative visual acuity. The problem of assessment when lens opacity is advanced is addressed in Part II.

Aged↗
PubMed1991

Assessment of contrast sensitivity. Part II: The relationship between objective lens opacity and laser interferometric contrast sensitivity in the cataract patient.

The laser interferometer can effectively bypass the optics of the eye and measure retinal function in patients with immature cataracts. However, it is not known how much laser interferometric measurements are impaired by cataract density. In this study we compared objective lens opacity using the IntraOptics opacity lensmeter with contrast sensitivity (CS) measured by a Randwal He-Ne laser interferometer. Comparison of lens opacity with CS in the cataract population revealed an inverse linear relationship between objective lens opacity and retinal contrast sensitivity. Separation by cataract type showed correlation coefficients as high as -0.91 for nuclear sclerotic predominant cataracts and as low as no significant correlation for posterior subcapsular predominant cataracts. Comparisons of before and after implantation surgery contrast sensitivities (as measured by the laser interferometer) with preoperative lens opacities (as measured by the IntraOptics opacity lensmeter) quantified the extent to which laser interferometric measurements underestimated potential retinal function. We found that for all cataracts, other than posterior subcapsular predominant cataracts, potential contrast sensitivity (in decibels) was underestimated by about 0.2 to 0.3 times the opacity measured by this technique.

Adult↗
PubMed1988

Hemangiopericytoma of the ciliary body.

A 60-year-old woman had a ciliary body tumor that resembled an amelanotic malignant melanoma by clinical examination. The magnetic resonance imaging scan correlated with the clinical diagnosis. Because of apparent rapid growth, her eye was enucleated. However, histopathologic examination revealed a highly vascularized, spindle-cell tumor harboring immunoreactive actin and vimentin. Electron microscopy further supported the diagnosis of hemangiopericytoma with smooth-muscle differentiation. To our knowledge, this is the first report of a hemangiopericytoma of the ciliary body.

Ciliary Body↗
PubMed1985

Phthisis bulbi after intraocular lens implantation in a child.

A 4-year-old boy with trisomy 21 and a congenital cataract underwent cataract extraction and implantation of an iris-supported intraocular lens (IOL). Four years later the implant dislocated anteriorly and had to be removed. Now, 11 years postoperatively, the eye is blind, painful and shrunken. IOL implantation in infants and children is theoretically justified to preserve vision, reduce amblyopia and preserve fusion. The use of modern posterior chamber IOLs, especially when implanted in the lens capsular bag (if technically feasible), could reduce the risk of complications. However, until further data are accumulated, a conservative approach is warranted.

Blindness↗
PubMedDate not supplied

Melanocytoma: nomenclature, pathogenesis, natural history and treatment.

A melanocytoma (magnocellular nevus) is a benign pigmented tumor that may arise wherever uveal melanocytes are present. The most commonly observed site is on or adjacent to the optic nerve head. In the past this tumor was frequently misdiagnosed as a malignant melanoma and many unnecessary enucleations were carried out. Its clinical features are now well recognized and, fortunately, specimens of melanocytomas are rarely received in ocular pathology laboratories today. A review of the literature concerning this tumor is presented, with special reference to the changing concepts in nomenclature, pathogenesis, natural history, and treatment that have evolved in the past one hundred years. We also define the clinical and histopathological features of this tumor.

Cell Transformation, Neoplastic↗