A novel pancreatic model: the snip method of pancreatic isolation for in vitro study.

We aimed to devise a method of preparing the pancreas for in vitro study that would provide tissue that is viable and functional for 24 h, with preservation of integral functional cell-membrane structures. Pancreata of NIH Swiss mice were excised, gently insufflated with media, and carefully snipped into portions of < 0.5 mm. Snips were incubated in cell culture for 0, 8, 24, and 48 h, with viability measured by 3-[4,5-dimethylthiazol-2-yl]-2,3-diphenyltetrazolium bromide (MTT) assay and amylase production quantified after stimulation with cerulein. Recombinant tumor necrosis factor-alpha (TNF-alpha) was added to cell culture, and apoptosis demonstrated by Hoechst staining at 0, 24, and 48 h. At 0, 8, and 24 h, pancreatic snips were determined to be viable by MTT assay. They also were functional with intact cell-membrane apparatuses at these same time points, as evidenced by amylase production in response to a cholecystokinin analogue. We were able to induce apoptosis with TNF-alpha ligand in these pancreatic snips in support of viability and overall cellular function. We conclude that the snip method provides an effective in vitro pancreatic model. Acinar cells are viable and functional for > or = 24 h, with evidence that their cell-surface receptors are preserved in their operational state.

Dislocation of Binkhorst four-loop lens implant.

A consecutive series of 1,093 Binkhorst four-loop lens implantations was used to examine the problem of dislocation of implants used in intracapsular cataract extractions; emphasis of the study was on the need for suture fixation. Transiridectomy suture fixation was used in 497 procedures, no suture was used in 403 procedures, and a simple iris suture technique was used in 193 procedures. Although the transiridectomy suture fixation procedure had the lowest percentage of dislocations, the iris suture technique is considered safer. Suture fixation is recommended for Binkhorst four-loop implants used in intracapsular cataract extractions.

Lens implantation, miosis, and glaucoma.

In a series of 1,079 patients, average age 76.3 years, 48 eyes required an iridoplasty for chronic miosis and, of these, visual acuity was 6/12 (20/40) or better postoperatively in 89.6% (43). In those patients with glaucoma, the control of intraocular pressure was the same or better than post-operative levels in 83.3% (15) of patients. Lens implantation was not contraindicated in the miotic patient if adequate iris surgery was performed before both cataract extraction and implant insertion. When there was concomitant glaucoma, lens implantation was likewise not contraindicated if the glaucoma was well controlled.

Pars plana vitrectomy as a primary treatment for acute bacterial endophthalmitis.

We successfully treated six patients with culture-proven acute bacterial endophthalmitis by a combination of emergency pars plana vitrectomy and the instillation of intravitreal antibiotics. All six patients regained satisfactory vision.

A comparison of 500 Binkhorst implants with 500 routine intracapsular cataract extractions.

We compared 500 Binkhorst lens implants with 500 routine intracapsular cataract extractions. The two groups consisted of consecutive cases matched according to surgeons, surgical technique, time interval of the study, and ocular status. The results of visual acuity were comparable in the two groups; 89.0% of the implant group and 85.4% of the routine intracapsular group achieved 6/12 (20/40) or better visual acuity. The rate of complications in each group was comparable except in the case of corneal edema, which was higher in the implant group (1.2%) than in the routine intracapsular group (0.4%). The rate of clinically significant cystoid macular edema was higher in the routine intracapsular group (2.2%) than in the implant group (1.4%).

Pars plana vitrectomy for complications of intraocular lens implantation.

Several clinical situations have been presented in which pars plana vitrectomy has proven beneficial in the treatment of vitreous complications of lens implantation. Removal of the central opacity and enlargement of the pupil are essential to improve vision, relieve pupillary block and achieve an adequate view of the retina. Pars plana vitrectomy offers a method for the controlled removal of membrane, vitreous and iris tissues without unnecessary distortion of anterior segment anatomy.

Lens implantation surgery in the second eye.

In a series of 730 patients who underwent lens implant surgery, 44 (6%) had bilateral implants. Eighty-eight percent of these patients had at least one year's interval between operations and 50% more than two years. Surgery on the first eye resulted in vision of 20/40 or better in 86% of patients. Eighty-three percent of patients were 20/40 or better in the second eye following surgery. The principal cause of vision less than 20/40 was senile macular degeneration. Follow-up observation ranged from 4-96 months. Conservative criteria are advised for bilateral implant surgery, with an appropriate interval between operations considering the increased complexity of the implant procedure.

Bimanual, bipolar intraocular diathermy.

We performed bimanual, bipolar intraocular diathermy by using a No. 22 disposable needle and a vitrectomy instrument. The technique required a smaller wound than unimanual bipolar cautery and was combined with membrane peeling techniques. The bipolar technique limited the extent of coagulation effects better than unipolar diathermy methods.

A chin-operated switch for motorized three-axis microscopic movement.

A chin-operated switch was developed to permit control of motorized operating microscope movement simultaneously along three axes. It permits use of both feet to operate surgical modalities, decreases microscope positioning time, and decreases needless hand movements.

Mechanical syringe drive for vitreous surgery.

A mechanical syringe drive permits one-handed, precise control of the suction force at the time of vitrectomy, is autoclavable, utilizes disposable syringes, and can be operated by surgeon or assistant.