Adjunctive chemotherapy with Mitomycin C (MMC) has been used in an attempt to modulate the wound healing response in glaucoma filtration surgery. A consecutive series of 20 eyes from 18 patients undergoing trabeculectomy with MMC intraoperatively was studied. Sixteen cases were considered high risk regarding surgical success and 4 patients with low tension glaucoma (LTG) required lower intraocular pressure (IOP) to prevent further visual field loss. Surgical technique involved the use of a limbal-based conjunctival flap and MMC 0.2 mg/ml applied via a sponge (under the scleral flap) to both scleral and conjunctival surfaces for 5 minutes. The mean follow-up period was 12.7 months (range 3-24). There were 17 successful eyes. Of these, 14 are high pressure glaucoma eyes with a mean pre-operative IOP of 30.9 +/- 10.9 mmHg and a mean postoperative IOP of 15.3 +/- 5.2 mmHg (p = 0.001). The remainder of the successful cases include 4 patients with LTG with a mean preoperative IOP of 17.8 +/- 0.5 mmHg and a mean postoperative IOP of 6.8 +/- 0.7 mmHg (p = 0.001). Serious complications included chronic repeated bleb leaks (n = 2) and scleral necrosis (n = 2). There was one case of hypotonous maculopathy. These results are comparable with those of other studies. Despite a relatively low dose of MMC serious side-effects were encountered. Management of these complications is described, and how these effects may be prevented by altering scleral exposure to MMC. In addition a possible explanation for the serious side-effects of MMC-treated trabeculectomies is presented.

Adult↗

PubMed1995

Measurement of ocular blood flow velocity using colour Doppler imaging in low tension glaucoma.

The purpose of this study was to compare the velocity of blood flow and vascular resistance measured by colour Doppler imaging in the ophthalmic and central retinal arteries in 34 eyes of 34 patients (mean age 68.1 years) with low tension glaucoma (LTG) and 17 eyes of 17 age-matched normal controls (mean age 65.2 years). The Acuson 128 machine (using a 7.5 MHz probe) was used to measure peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistive index (RI). The EDV of the ophthalmic artery (OA) in the LTG was significantly (p = 0.04) less than in the normal control group. There was a significant (p = 0.02) increase in the vascular RI of both the OA and central retinal artery in the LTG group compared with the normal controls. The OA RI increased with age (r = 0.61, p = 0.0001), and the OA EDV decreased with age (r = -0.50, p = 0.003), in the LTG group but not in the normal control group. The results suggest an increased resistance to blood flow in the ophthalmic and central retinal arteries of LTG patients.

Aged↗

PubMed1995

Use of tissue culture models to study environmental-genetic interactions relevant to neurodegenerative diseases.

1. Clonal cell lines, primary cultured neurones and transgenic animals expressing mutant genes linked to familial forms of neurodegenerative diseases provide models in which to examine the interaction between expression of a predisposing gene and exposure to neurotoxic chemicals. Methods of establishing these models are reviewed. 2. Mutations in the gene encoding Cu/Zn-superoxide dismutase (SOD-1) have been identified in cases of familial amyotrophic lateral sclerosis linked to chromosome 21. We report that in clonal lines of PC12 cells, the cytotoxicity of a glutathione-depleting epoxide, styrene oxide, varied with SOD activity in a manner similar to that previously demonstrated for redox cycling chemicals. These preliminary data suggest that either low or high SOD-1 activities may be associated with greater toxicity of a variety of neurotoxic chemicals and their metabolites.

Amyotrophic Lateral Sclerosis↗

PubMed1995

Automated perimetry in glaucoma--room for improvement?

Explore the source record for details and available documents.

Glaucoma↗

PubMed1995

Effect of temporal frequency and contrast on peripheral grating resolution.

We measured resolution at 10 degrees in the inferior temporal retina using horizontal and vertical gratings of different contrasts which modulated in time at temporal frequencies from 0 to 40 Hz. Since peripheral grating resolution is directly related to the sampling density of retinal ganglion cells this allowed us to observe changes in responding ganglion cell density as the stimulus properties changed to selectively stimulate magnocellular pathway cells (M cells) instead of parvocellular pathway cells (P cells). At all contrasts there was no decline in resolution performance up to 10 Hz, after which resolution deteriorated significantly, this effect being greater at lower contrasts. The predicted psychophysical resolution limit for M cells calculated from the anatomical data of Dacey indicates that resolution for high temporal frequency (30 Hz) or low contrast (5%) stimuli is too good to be mediated by M cells alone and there is still significant P cell stimulation by these stimuli.

Contrast Sensitivity↗

PubMed1995

Factors affecting non-attendance in an ophthalmic outpatient department.

The object of the study was to establish the non-attendance rates in an ophthalmic outpatient department and any non-attendance patterns that may be useful in managing future outpatient resources. A detailed retrospective survey of monthly non-attendance rates was carried out in the outpatient department of a dedicated eye hospital over a 1 year period looking at differences in non-attendance between morning and afternoon clinics and new and review patients. A total of 43,004 scheduled outpatient appointments predominantly from the suburban population of the Merseyside region were made at St Paul's Eye Hospital from the 1 February 1990 to 31 January 1991. Five thousand four hundred and twenty-four appointments were missed giving an overall non-attendance rate of 12.6%. Non-attendance rates for morning and afternoon appointments were 12.0% and 13.0%, respectively: and for new and review patients, 11.9% and 12.8%, respectively. Logistic regression analysis showed that patients with afternoon appointments were on average 1.10 times more likely to non-attend than morning patients (P = 0.002), and that review patients were 1.09 times more likely to non-attend than new patients (P = 0.04). In order to maximize outpatient department efficiency, a reduction in non-attendance is essential. Establishing patterns for non-attendance provides us with a framework around which we can plan measures to compensate for outpatient non-attendance.

England↗

PubMed1995

Supratentorial haemangioblastoma not associated with Von Hippel Lindau complex or polycythaemia: case report and literature review.

Solitary or multiple supratentorial haemangioblastomas are rare and may be associated with Von Hippel Lindau complex (VHLC), polycythaemia or a family history of VHLC. An extensive review of the literature (1902-1992) has revealed 112 cases. They account for 2-8% of all haemangioblastomas and are commonly intraparenchymatous (86.8%) and infrequently intraventricular (6.6%). However, a meningeal location 5.6%) is extremely rare. Only one case of a solitary leptomeningeal haemangioblastoma has previously been reported and this was associated with a family and personal history of VHLC, cerebellar haemangioblastoma and renal carcinoma. We report a solitary solid left parietal leptomeningeal haemangioblastoma mimicking a meningioma or a secondary deposit on computed tomography in a 72-year-old male. There were no manifestations of or a family history of VHLC or polycythaemia.

Aged↗

PubMed1994