ABSTRACT
The Food and Drug Administration's approval of the excimer laser in 1995 heralded the age of laser refractive surgery in the United States. Since then, other advances in refractive surgery have spurred great public interest in and enthusiasm for these procedures. In this article, the authors review the major types of refractive surgery and discuss their indications, results, and complications.
Subject(s)
Laser Therapy/methods , Ophthalmologic Surgical Procedures , Refractive Surgical Procedures , Humans , Keratotomy, Radial/methods , Lasers, Excimer , Photorefractive KeratectomyABSTRACT
OBJECTIVE: To compare the effectiveness of limbus-based and fornix-based conjunctival flaps in fellow eyes of the same patients undergoing combined trabeculectomy with phacoemulsification. DESIGN: Prospective, nonrandomized comparative (fellow eye) study. PARTICIPANTS: Forty-four patients and 88 fellow eyes. INTERVENTION: Limbus-based conjunctival flap with phacotrabeculectomy was performed in one eye, and a fornix-based conjunctival flap with phacotrabeculectomy was performed in the fellow eyes of the same patients. The patients were followed up for a minimum of 1 year postoperatively for each eye. MAIN OUTCOME MEASURES: Preoperative and postoperative visual acuity, intraocular pressure, number of antiglaucoma medications, interventions, and complications were studied. RESULTS: At last follow-up visit, visual acuity improved to 20/40 or better in 88.6% of the limbus-based group and 79.6% of the fornix-based group. Preoperatively, the mean intraocular pressure in the limbus-based group was 21.4 +/- 4.8 mmHg on a mean of 2.4 +/- 1.2 glaucoma medications; in the fornix-based group, it was 21.4 +/- 4.3 mmHg on a mean of 2.3 +/- 1.1 medications. Mean intraocular pressure decreased to 15.3 +/- 3.3 mmHg (P < 0.01) on a mean of 0.2 +/- 0.5 glaucoma medications in the limbus-based group (P < 0.01). In the fornix-based group, mean intraocular pressure at last follow-up visit decreased to 15.3 +/- 4.7 mmHg (P < 0.01) on a mean of 0.2 +/- 0.5 medications (P < 0.01). Postoperative interventions and complications were not statistically different between the two groups. CONCLUSION: With phacotrabeculectomy, limbus-based and fornix-based conjunctival flaps are equally effective in improving visual acuity and lowering intraocular pressure. This variation in conjunctival flap orientation was equally effective in fellow eyes of the same patients, with no difference in postoperative complications or outcomes.
Subject(s)
Conjunctiva/surgery , Limbus Corneae/surgery , Phacoemulsification , Surgical Flaps , Trabeculectomy , Aged , Cataract/complications , Female , Follow-Up Studies , Glaucoma/complications , Glaucoma/surgery , Humans , Intraocular Pressure , Lens Implantation, Intraocular , Male , Polymethyl Methacrylate , Postoperative Complications , Prospective Studies , Treatment Outcome , Visual AcuityABSTRACT
Alkaline phosphatase, confined to myoepithelial cells and blood capillaries in rat submandibular salivary gland (SSG), may participate in the regulation of salivary flow. To determine whether the alkaline phosphatase of SSG has unique properties, comparative kinetic and inhibition studies on enzymes from SSG, intestine and kidney were performed. The Km values (at optimal pH for each tissue) of 0.34, 0.55 and 0.49 mM with p-nitrophenylphosphate for the enzymes from SSG, kidney and small intestine respectively were similar. However, in the presence of cadmium the Ki values of 0.08 and 0.12 microM for the enzymes from SSG and kidney respectively were different from the value of 1.86 microM for the enzyme from small intestine. Differences in Ki values suggest differences in biochemical properties between the enzyme from small intestine and that isolated from SSG or kidney.
Subject(s)
Acetates , Alkaline Phosphatase/metabolism , Cadmium/pharmacology , Submandibular Gland/enzymology , Alkaline Phosphatase/antagonists & inhibitors , Animals , Intestine, Small/enzymology , Kidney/enzymology , Kinetics , Male , Rats , Rats, Inbred Strains , Zinc/pharmacologyABSTRACT
Studies in several laboratories have shown that nutritional Zn deficiency in the rat causes a reduction in the activity of certain Zn-dependent enzymes in kidney, intestine, pancreas, etc. The present report deals with the effects of Zn-deficiency on submandibular gland of the rat. For the sake of comparison with previous studies, some assays on pancreas were included. Protein content, DNA, acid phosphatase, and acid protease activities were not affected in submandibular gland. Lactate dehydrogenase was unaffected in submandibular gland and showed increased activity in pancreas. Malate dehydrogenase was significantly decreased in both organs, the decrease being more marked in submandibular gland. Alkaline phosphatase activity in submandibular glands of control rats was about 10-fold higher than in pancreas. In the zinc-deficient rats, alkaline phosphatase was reduced to 59% of controls in the submandibular glands and to about 75% in pancreas. It is known from histochemical studies that in the submandibular gland this enzyme is confined to the myoepithelial cells. Recent studies attribute to salivary glands a role in the etiology of taste disturbances seen in clinical states of zinc deficiency. It is proposed that functional impairment of the myoepithelial cells might contribute to the disturbance of taste.