Risk factors for pain and nausea following retinal and vitreous surgery under conscious sedation.

BACKGROUND: There have been no studies examining risk factors for pain and nausea during the first day after posterior segment surgery. We performed a study to identify significant risk factors for the development of pain and nausea during the first 24 hours after outpatient vitrectomy or scleral buckle surgery. METHODS: A total of 257 consecutive patients who underwent vitrectomy (192 patients), scleral buckling (57 patients) or combined vitrectomy-scleral buckling (8 patients) between July 1 and Dec. 31, 1995, were enrolled in this prospective study. The patients' age, sex and ethnicity, the duration of the procedure and the intraoperative use of minor tranquillizers, hypnotic agents, narcotic analgesics or major tranquillizers were recorded. Each patient rated his or her postoperative pain and nausea on two separate 100-mm lines. The left end of the line represented no pain (or nausea) whatsoever, and the right end of the line represented severe pain (or nausea). The distance of the recorded point from the origin of the line was used as the outcome measure for pain and nausea. All the data were analysed statistically by means of logistic regression analysis and descriptive statistics. RESULTS: The median pain scores were 1.0 for the patients who underwent vitrectomy, 47.0 for those who underwent scleral buckling and 35.0 for those who underwent combined vitrectomy-scleral buckling. The median nausea scores were 14.5, 45.0 and 55.5 respectively. The only variable that was identified as a predictor of postoperative pain or nausea was the intraoperative use of narcotic analgesics: in the vitrectomy group, postoperative nausea occurred almost three times as often among patients who received these agents as among those who did not (odds ratio 2.6, p = 0.00). INTERPRETATION: The identification of the intraoperative use of narcotic analgesics as a risk factor for nausea in the first 24 hours after outpatient vitrectomy suggests that, when possible, these agents should be avoided during surgery.

Surgical removal of subretinal hemorrhage and choroidal neovascular membranes in acute hemorrhagic age-related macular degeneration.

The visual prognosis in patients with age-related macular degeneration in whom an acute extensive subretinal hemorrhage develops involving the centre of the fovea is extremely poor. We report our results in seven consecutive patients with acute hemorrhagic age-related macular degeneration who underwent pars plana vitrectomy with internal drainage of blood lying beneath the retina and the retinal pigment epithelium. In three of the patients subretinal choroidal neovascular membranes were also removed. Five patients, including three of the four who underwent surgery within 2 weeks of the onset of symptoms, had improved vision following surgery, in one patient choroidal neovascularization recurred, and one patient experienced no change in vision. The best results were obtained in the four patients who did not undergo deliberate dissection of choroidal neovascular membranes.

The structure of the developing chick retinal pigment epithelium revealed by high resolution scanning electron microscopy.

The retinal pigment epithelium (RPE) in the developing eye of chick embryos has been studied during the early stages of development by high resolution scanning electron microscopy (HRSEM). Specimen preparation techniques which involve removal of the cytoplasmic matrix permitted visualization of organelles and other subcellular structures within RPE cells in detail and in three dimensional (3-D) stereo HRSEM. Using this technique, we were able to examine changes in melanosome structures during development and demonstrate that pigmentation in the RPE was present by day 4 of development. RPE plasma cell membranes showed extensive folding of the apical portion of the membrane closest to the developing neural retina by day 9. Examination of RPE photoreceptor junction revealed photoreceptor inner segments by day 6 and an outer segment by day 9. Mitochondria in the RPE were found to contain tubular cristae only. The ultra-structure in 3-D of the Golgi apparatus, smooth and rough endoplasmic reticulum, lysosomes and nuclear chromatin of the RPE, and Bruch's layer was revealed by the HRSEM method.

Abnormalities of the optic fundus.

Common abnormalities of the optic fundus are illustrated in this article. The authors provide brief clinical descriptions and discuss a test used to screen for a shallow anterior chamber of the eye before dilating the pupil.

Preretinal membranectomy in idiopathic preretinal macular fibrosis.

Idiopathic preretinal macular fibrosis (PMF) rarely causes progressive loss of vision. In 5 of 350 cases in which vision did markedly diminish, pars plana vitrectomy and membranectomy proved to be a useful surgical method of correcting the visual loss. There was an apparent recurrence of PMF in two of the five cases.

Papilledema without peripheral neuropathy in a patient taking perhexiline maleate.

Perhexiline maleate is an agent currently under investigation in Canada that is used for angina unresponsive to other treatment. This paper describes a possible side effect previously unreported--papilledema not associated with peripheral neuropathy.

Vitreous and retinal surgery in pseudophakia.

We review scleral buckling and vitrectomy procedures in thirteen pseudophakic eyes. Pre-operative difficulties in visualizing the fundi were few. Despite operative complications due to the implant, 90% of the retinas were reattached. Late complications involving particularly the anterior segment in both the buckling and vitrectomy groups caused the poor visual results.

Eccentric serous choroidopathy: a case report.

A patient presented with a serous detachment of the retina outside the macular region in one eye and three years later a similar detachment in the fellow eye. The clinical findings were otherwise identical to those seen in patients with idiopathic central serous choroidopathy. Idiopathic eccentric serous choroidopathy is probably a variant of idiopathic central serous choroidopathy. Its occurrence may be implications in understanding the pathogenesis of the latter condition.

Computed axial tomography localization of intra-orbital foreign body.

Conventional radiographs in a patient with an intra-orbital foreign body showed that it was close to the back of the globe. Computed axial tomography showed that it lay beside a swollen and probably lacerated optic nerve. The advantages of CT scanning in the investigation of intra-orbital foreign bodies are outlined.

Laser iridotomy in post-traumatic and post-surgical pupillary block: a report of five cases.

In five cases of aphakic pupillary block after trauma or surgery we found laser iridotomy to be a simple, effective, non-invasive alternative to operation in relieving pupillary block where medical management had failed.

Intra-operative hyphema: a complication of retinal detachment surgery with the Choyce pseudo-phakos.

During retinal reattachment surgery in an eye with a Choyce pseudo-phakos a large hyphema developed. The probable mechanism was rupture of blood vessels in the angle of the anterior chamber during drainage of sub-retinal fluid as all the eye structures collapsed around the rigid pseudo-phakos.