Biomedical subjects

S D Potash

Publications and source records attributed to S D Potash.

6 recordsLinked to original sources

PubMed1994

Ultrasound biomicroscopy in pigment dispersion syndrome.

PURPOSE: To examine the positional relations of the iris, lens, ciliary processes, and zonules in eyes with the pigment dispersion syndrome (PDS). METHODS: High-resolution, anterior segment ultrasound biomicroscopy was performed on 16 untreated eyes of 11 patients with PDS. Scanning was repeated on four eyes after miotic treatment and four eyes after laser iridotomy. RESULTS: Mid-peripheral iris concavity could be demonstrated in 56%, irido-zonular contact in 25%, and irido-ciliary process contact in 75% of untreated eyes with PDS. Repeat scanning after laser iridotomy or pilocarpine therapy showed resolution of the iris concavity and irido-zonular contact in all eyes receiving these therapies. Irido-ciliary process contact persisted in some eyes. CONCLUSION: The authors' findings demonstrate the structural relations among the iris, lens, zonules, and ciliary processes in vivo that characterize the PDS. Miotic therapy and laser iridotomy eliminate the iris concavity in all patients with this finding, supporting the hypothesis of reverse pupillary block. Irido-ciliary process contact may be another mechanism causing release of pigment. This issue merits further clinical and histologic study.

Adolescent↗

PubMed1994

Measurement of ultrasound biomicroscopy images: intraobserver and interobserver reliability.

PURPOSE: To evaluate intraobserver and interobserver reproducibility of measurement of images obtained during ultrasound biomicroscopy. METHODS: Four anterior segment images of four normal patients were obtained by a single examiner. The measurements of three independent observers were compared to assess interobserver reproducibility in quantifying the images. Thirteen different anterior segment parameters were measured by each observer on each image. Intraobserver and interobserver reproducibility of measurement were assessed by calculating the coefficient of variation for each individual observer and by using the F test to detect a difference among observers. RESULTS: Intraobserver reproducibility was high. Interobserver reproducibility for the measured parameters varied considerably and was affected by subjective interpretation of visualized anatomic landmarks. CONCLUSIONS: The optimal parameters for quantitative ultrasound biomicroscopy require refinement. Measurements of alterable parameters are best measured presently by a single observer. Ultrasound biomicroscopy has the potential to elucidate anatomic relationships underlying much anterior segment disease, but caution in interpreting quantitative differences is warranted.

Anterior Eye Segment↗

PubMed1994

A new lens for argon laser suture lysis.

Argon laser suture lysis is a valuable adjunct for regulating intraocular pressure and establishing a filtration bleb in the early postoperative period after trabeculectomy. We have developed a lens that provides excellent compression of the conjunctiva, an improved view of scleral flap sutures, and effortless retraction of the upper lid.

Argon↗

PubMed1993

Ocular hypotony and choroidal effusion following bleb needling.

A choroidal effusion, hypotony, and a shallow anterior chamber developed in a patient following a transconjunctival needling revision of an encapsulated filtering bleb. While choroidal effusions occur frequently following filtration surgery, to our knowledge, this complication has not been previously reported following a filtering bleb needle revision.

Choroid Diseases↗

PubMed1988

Enhancement of the ocular hypotensive effect of acetazolamide by diflunisal.

We studied the effect of diflunisal on intraocular pressure in patients with glaucoma who were receiving maximally tolerated therapy. Diflunisal therapy, 500 mg twice daily, was started in 48 patients for one week. No changes were made in their regular antiglaucoma medications. Intraocular pressure was reduced an additional 3.8 +/- 3.1 mm Hg (+/- S.D.) in the acetazolamide-treated patients (P less than .0001) and 1.6 +/- 1.5 mm Hg in methazolamide-treated patients (P less than .02), while no significant reduction in intraocular pressure was found in patients receiving topical medications alone. In 15 acetazolamide-treated patients, total plasma concentrations of acetazolamide after diflunisal therapy were significantly higher than the prediflunisal levels, suggesting a modest decrease in renal excretion. In seven acetazolamide-treated patients, free plasma concentrations of acetazolamide were found to increase 5.6-fold after diflunisal therapy. We concluded that diflunisal potentiated the ocular hypotensive effect of acetazolamide by increasing its free plasma level.

Acetazolamide↗

PubMed1988

Asymptomatic physiologic hyperdeviation in peripheral gaze.

Asymptomatic hyperdeviation (HD) in peripheral gaze may be caused by muscle paresis, restrictive orbital diseases, cranial neuropathy, or skew deviation. The authors suspected that this finding was often physiologic and therefore examined 61 normal subjects with the Maddox rod. Forty-seven of 61 patients (77%) showed an HD of 2 prism diopters (PD) or greater in any field of gaze; 22 of these 47 patients (47%) showed an isolated left HD in right upgaze and right HD in left upgaze; an additional 15 of the 47 patients (32%) had either a right HD in left upgaze or a left HD in right upgaze. In only one patient was a vertical phoria evident in primary gaze. Ninety-four percent noted vertical diplopia where the deviation was found. In 40 of 47 patients (85%), a "V" pattern of less than 15 PD was detected. No HD in primary gaze on head tilt was elicited in those tested. Awareness of this highly prevalent physiologic HD, which follows the pattern of primary overaction of the inferior oblique muscle, may ward off erroneous neurologic diagnoses.

Adult↗