Biomedical subjects

M A Van der Karr

Publications and source records attributed to M A Van der Karr.

3 recordsLinked to original sources

PubMed1996

Combined cataract and glaucoma procedures using temporal cataract surgery.

PURPOSE: To evaluate whether separating the procedures in a combined procedure by performing a temporal cataract incision and superior trabeculectomy induces the lower astigmatism of a temporal cataract incision without sacrificing intraocular pressure (IOP) control. SETTING: EyeSight Associates, Warner Robins, Georgia. METHODS: This study evaluated 50 consecutive eyes receiving a superior cataract incision with a superonasal trabeculectomy and 65 eyes receiving a temporal cataract incision with a superonasal trabeculectomy. RESULTS: After 3 months, a substantially greater proportion of temporal incision cases had controlled IOP without medication. A substantially higher proportion in the superior incision group had uncontrolled IOP at each time period. Mean surgically induced cylinder was higher in the superior incision group at every time period. The superior group had early with-the-rule mean induced cylinder that decayed to against-the-rule, with a mean induced cylinder with keratometry at the final available visit (more than 3 months) of -1.01 diopter (D). The temporal group started with a negligible induced cylinder (-0.13 D) that drifted slightly with the rule to a final mean induced cylinder of +0.49 D. At the last visit, 31% in the superior incision group and 57% in the temporal incision group had an uncorrected visual acuity of 20/40 or better, and 72% and 94%, respectively, had a best corrected acuity of 20/40 or better. CONCLUSION: Separating the cataract and glaucoma procedures frees the surgeon to use newer astigmatically neutral techniques for the cataract incision.

Aged↗

PubMed1994

Excimer laser phototherapeutic keratectomy for treatment of recurrent corneal erosion.

Two patients with a history of frequent recurrent corneal erosion for whom standard medical therapy was determined ineffective had phototherapeutic keratectomy (PTK) with an excimer laser. Before treatment, one patient had four episodes in a six-month period; the other had ten to 20 recurrences with four serious episodes in a seven-month period. After PTK, neither patient had a recurrence after 18 months follow-up. Subjectively, both patients felt the treated area healed faster than previous abrasions. Vision, refraction, keratometry, and corneal thickness measurements appeared unaffected by the treatment.

Adult↗

PubMed1992

Effect of small incision intraocular lens surgery on postoperative inflammation and astigmatism. A study of the AMO SI-18NB small incision lens.

A single center, single surgeon, randomized, prospective clinical trial was performed comparing the effectiveness of small (3.5 mm to 4.0 mm) incision intraocular lens surgery and a larger (6.0 mm) incision in improving uncorrected visual acuity and reducing post-operative inflammation and surgically induced astigmatism. One hundred twelve eligible unilateral cases were randomized to receive a 3.5 mm to 4.0 mm incision with implantation of an Allergan Medical Optics three-piece SI-18NB silicone lens (56 cases) or a 6.0 mm incision with implantation of a three-piece biconvex poly(methyl methacrylate) lens (56 cases). At one day after surgery, significantly (P less than .01) more patients with 3.5 mm incisions had 20/40 or better uncorrected visual acuity than patients with 6.0 mm incisions (45% vs 20%). Forty percent of patients with 6.0 mm incisions vs 14% of patients with 3.5 mm incisions had visual acuities of 20/100 or worse. At one day after surgery, the larger incision group had significantly higher (P less than .01) mean keratometric cylinder (2.28 diopters vs 1.28 diopters in the small incision group). The two groups were comparable by three months. Laser flare/cell meter measurements were taken for each group but showed no significant differences in mean flare or cell measurements between the groups.

Aged↗