Search PubMed⌕ Search

Biomedical subjects

D R May

Publications and source records attributed to D R May.

At least 37 records · Page 2Linked to original sources

Results of 110 vitrectomies with a portable vitrectomy system.

We retrospectively evaluated the VITAC (vitreous-tissue aspiration cutter), a portable vitrectomy system with an end-cutting vitrectomy probe with a self-sharpening oscillating blade and a monoblock design, in 110 vitrectomy procedures, 34 performed at the University of California Davis Medical Center and 76 performed at the Eye and ENT Hospital in Shanghai, China. The indications for vitrectomy included penetrating injuries (22 eyes), intraocular foreign bodies (28 eyes), vitreous hemorrhages (18 eyes), cataracts (17 eyes), endophthalmitis (seven eyes), pupillary-block glaucoma (five eyes), bullous keratopathy (five eyes), aphakic penetrating keratoplasty (three eyes), pupillary membranes (two eyes), massive preretinal proliferation (one eye), and cystoid macular edema (one eye). Vitrectomy resulted in visual improvement in 19 of 34 eyes in the California series (56%) and in 60 of the 76 eyes in the Shanghai series (79%). This difference was attributable to the higher percentages of cases involving the posterior segment and vitreous hemorrhage in the California series. When results from both institutions were combined, surgery with the VITAC produced visual improvement in 79 of 110 cases (72%), comparable to the results obtained with other vitrectomy systems.

Eye Diseases↗

Effect of hypothermic perfusion on corneal endothelial morphology.

The effect of moderate in-vivo hypothermic perfusion on corneal endothelial integrity was studied in the cat. Eleven cats underwent in-vivo anterior chamber perfusion for 30 minutes with either normothermic (23 degrees C) or hypothermic (5 degrees C) perfusate. Corneas were then evaluated clinically (biomicroscopy), functionally (vital staining), and morphologically (scanning electron microscopy) for changes attributable to hypothermic perfusion. All 3 modes of evaluation suggested no difference in corneal endothelial integrity under the 2 experimental perfusion conditions. At the clinical and scanning electron microscope levels hypothermic perfusion does not show any effects on the corneal endothelium. Regional hypothermia is of theoretical and potential utility in procedures involving prolonged intraocular perfusion.

Animals↗

Ocular hypothermia: anterior chamber perfusion.

The anterior chambers of 27 rabbit eyes were perfused at constant pressure with room temperature (25 degrees C) or cooled (11 degrees C) balanced salt solution at constant flow rates of 4.8 ml/min or 8.5 ml/min. Intraocular temperature changes in the anterior chamber, anterior vitreous, mid vitreous, and posterior vitreous and on the retina surface were monitored with an intraocular thermocouple probe. Perfusion of the anterior chamber of the pigmented rabbit eye with cooled fluid significantly reduced the temperature of the anterior chamber and anterior vitreous and even that of the retina. Both an increase in the rate of perfusion and a lowering of the perfusion temperature enhanced the cooling effect. The observed decrease in temperatures returned to approximately normal 4 minutes following the cessation of perfusion.

Animals↗

Use of the temporary keratoprosthesis in the subacute management of massive ocular trauma.

The Landers-Foulks temporary operating keratoprosthesis was used in the treatment of a severe double perforating injury involving both the cornea and retina in a 12-year-old boy. The use of the keratoprosthesis permitted surgical intervention at the optimal time for successful treatment of the retina and vitreous, providing the patient with useful visual acuity. The temporary keratoprosthesis is an excellent device for the subacute management of massive ocular trauma involving both anterior and posterior segments.

Child↗

Aspergillus endophthalmitis in an intravenous drug user.

A 27-year-old male drug user administered methamphetamine hydrochloride solution intravenously (IV) from a storage vial. Within two weeks he was admitted with a fungal endophthalmitis of the right eye. A diagnostic and therapeutic vitrectomy was performed. Aspergillus fumigatus was cultured from the drug storage vial and the vitreous biopsy specimen. The endophthalmitis was not controlled by IV and intravitreal amphotericin B. Pathological examination revealed fungal abscesses in the vitreous and subretinal space.

Adult↗

An anterior segment 30 degree bent infusion needle.

The bend of an anterior segment 30 degree bent infusion needle allows for ease of positioning over the nose or brow during surgical procedures. This instrument is easily used in bimanual surgical techniques with standard vitrectomy probes. Infusion into the anterior chamber of the eye during anterior segment vitrectomy procedures has the advantage of maintaining the depth of the anterior chamber and preventing its collapse during surgery. This techniques is particularly useful in anterior membranectomy, capsulectomy, lensectomy, and other anterior segment procedures.

Anterior Chamber↗

Active central retinal artery embolization.

A 44-year-old white woman with metastatic breast carcinoma and ongoing showers of branch and central retinal artery emboli is presented. The patient had no ocular complaints and demonstrated no cumulative effect from the embolic material, the cause of which remained undetermined despite intensive systemic medical evaluation.

Adult↗

Cardiopulmonary arrest after retrobular block.

A 61-year-old woman experienced a cardiopulmonary arrest immediately after the retrobulbar injection of a mixture of 2 ml of 0.5% bupivacaine HCl, 2% mepivacaine HCl, and hyaluronidase. The patient was immediately resuscitated but remained unconscious for a total of 20 minutes. All neurologic deficits resolved completely over the two hours following the cardiopulmonary arrest and no adverse sequelae were noted. We assumed that this cardiopulmonary arrest was precipitated by the local anesthetic being transported via retrograde flow through the ophthalmic artery and then by antegrade flow through the internal carotid artery to the thalamus and other midbrain structures.

Anesthetics, Local↗

Treatment of neovascular glaucoma with transscleral panretinal cryotherapy.

Transscleral panretinal cryotherapy was used to treat six eyes with neovascular glaucoma. The media of each involved eye were sufficiently cloudy at the time of treatment to prevent adequate panretinal photocoagulation. A checkerboard pattern of eight 2.5-mm cryotherapy applications was placed in each quadrant. Five of the eyes were also treated with 180 degrees of cyclocryotherapy. Within 72 hours of treatment, the intraocular pressure in each eye returned to a controllable level. The iris neovascularization in each eye regressed or totally disappeared within six weeks.

Aged↗

Central retinal artery occlusion following cosmetic blepharoplasty.

A case is presented of a 70-year-old white male who underwent a bilateral cosmetic lower lid blepharoplasty with fat removal. He subsequently developed a right orbital haemorrhage which resulted in the occlusion of the central retinal artery. The patient had no light perception with his right eye for approximately 1 hour, but vision was eventually restored to 20/20 after emergency therapeutic measures. There are many possible causes of visual loss following blepharoplasty, with orbital haemorrhage being the most common. Visual loss secondary to blepharoplasty can be prevented in the preoperative, intraoperative, and postoperative phases of surgery. Blindness as a complication of cosmetic blepharoplasty can be reversible if recognised early and treated appropriately. These facts must be kept in mind by all surgeons who perform blepharoplasties.

Aged↗

Xenon arc panretinal photocoagulation for central retinal vein occlusion: a randomised prospective study.

Thirty-three patients with central vein occlusion were evaluated for the effects of scatter xenon arc panretinal photocoagulation. Thirty-four eyes (2 eyes of 1 patient) were randomly divided into a treatment (15 eyes) and a nontreatment group (19 eyes). The average follow-up per eye has been 29 months. The visual prognosis was not significantly better in either group. There was no difference in the development of fundus neovascularisation between groups. None of the patients in the treated group developed rubeosis or neovascular glaucoma. Two patients in the nontreatment group initially had rubeosis and 3 developed it after entry. All 5 involved eyes developed neovascular glaucoma. A significantly greater amount of central retinal capillary drop-out was present in the untreated eyes that developed rubeosis than those untreated eyes which did not. The eyes in the treated group had a similar range of capillary drop-out area, but none of these eyes developed rubeosis or neovascular glaucoma. Panretinal photocoagulation prevented the development of rubeosis and neovascular glaucoma in susceptible eyes.

Adult↗

Metastatic Peptostreptococcus intermedius endophthalmitis after a dental procedure.

A 46-year-old man developed symptoms of a chronic progressive uveitis in his right eye approximately one week after a dental procedure. The patient's intraocular inflammation was not diminished by massive treatment with topical and systemic corticosteroid therapy or intravenously administered adrenocorticotropic hormone. The inflammatory process progressed to an overt endophthalmitis during a period of three weeks and the eye eventually required evisceration. A pure culture of Peptostreptococcus intermedius was isolated from the eye. The most likely source of this organism was hematologic transport following a dental procedure.

Bacterial Infections↗

Endophthalmitis caused by Propionibacterium acnes.

We treated a man who developed endopthalmitis six weeks after a seemingly minor injury. Cultures were positive for Propionibacterium acnes, an anerobic, Gram-positive rod that is a normal inhabitant of the conjunctiva but is rarely a cause of endophthalmitis. The patient underwent vitrectomy and lensectomy with intravitreal injection of antibiotics followed by systemic cephalothin and prednisone. Clinical and visual improvement was rapid.

Actinomycetales Infections↗

Intraocular gentamicin as intraoperative prophylaxis in South India eye camps.

The incidence of bacterial endophthalmitis has been 3-6% after cataract extraction in the eye camps of South India from 1961-75. During this time 50 791 cases were operated using systemic and topical chloramphenicol prophylaxis. This study evaluated the prophylactic intracameral injection of 50 microng of gentamicin in eye camp cataract extractions. Only 6 of 1626 patients treated with intracameral gentamicin at operation developed bacterial endophthalmitis, an incidence of 0-37%.

Bacterial Infections↗

Penetration of gentamicin into the aphakic eye.

The penetration of gentamicin is compared in the aphakic and phakic rabbit eye. Phakic and aphakic rabbits were treated with gentamicin by topical, subconjunctival, and intramuscular routes separately and in combination. These routes of therapy also were evaluated in aphakic eyes with experimentally induced endophthalmitis. The levels of gentamicin were, for the most part, higher in the aphakic, as opposed to the phakic eyes. Combination therapy produced higher levels in the noninfected than in the infected eyes. Aqueous levels were generally bactericidal by topical and subconjunctival routes. Levels in the vitreous by the routes of therapy employed in this study were at best inhibitory for the more virulent organisms.

Administration, Topical↗

Endophthalmitis after vitrectomy.

A 29-year-old white man with growth-onset diabetes developed fulminant endophthalmitis after vitreous lavage. The only significant symptom was severe pain 36 hours after surgery. The endophthalmitis rapidly became more severe. Despite systemic antibiotics, therapeutic vitrectomy and lensectomy, followed by the intraocular injection of antibiotics 48 hours postoperatively, the eye was lost.

Adult↗