Search PubMed⌕ Search

Biomedical subjects

C Gore

Publications and source records attributed to C Gore.

11 recordsLinked to original sources
PubMed2000

Refractive lensectomy for hyperopia.

PURPOSE: The purpose of this study was to evaluate refractive lensectomy as a surgical procedure for the treatment of hyperopia. DESIGN: A retrospective noncomparative case series. PARTICIPANTS: Twenty-nine patients were included in the study. Fifty eyes underwent extraction of the crystalline lens and intraocular lens implantation. METHODS: Operations were performed by the same surgeon with the patient under general anesthetic. All lenses were removed by phacoemulsification with insertion of lens implants singly or as piggyback lenses. The Holladay2 formula was used to calculate lens powers. Results are compared with other methods of treating hyperopia. MAIN OUTCOME MEASURES: The main parameters assessed were safety, efficacy, predictability, stability, and complications. RESULTS: Eyes were divided into group A (n = 26), with an average preoperative spherical equivalent (SE) of +2.26 +/- 0.94, and group B (n = 24), with an average preoperative SE of +6.32 +/- 1.32. In group A, after refractive lensectomy, 80.7% had no change in best-corrected visual acuity (BCVA) or gained a line, whereas 11.5% lost one line; 88.5% had an uncorrected visual acuity (UCVA) of 20/40 or better, and 88.5% were within 1 diopter (D) of intended postoperative SE. In group B, 70.9% of eyes had no change or gained a line in BCVA, whereas 29.2% lost a line of BCVA; 62.5% had UCVA of 20/40 or better postoperatively, and 58.3% were within 1 D of the intended SE. In one eye the posterior capsule was breached intraoperatively. One eye had a symptomatic episode of cystoid macula edema that settled spontaneously. To date, seven eyes have required secondary refractive procedures, and three eyes have required yttrium-aluminum-garnet capsulotomy. CONCLUSIONS: In the presbyopic age group refractive lensectomy may be a realistic alternative to photorefractive keratectomy or laser in situ keratomileusis, with certain potential advantages.

Female↗
PubMed1999

Cataract development after implantation of the Staar Collamer posterior chamber phakic lens.

Implantation of a posterior chamber phakic intraocular lens is an effective refractive procedure with a good safety record in the short-term follow-ups reported in the literature. Cataract formation is a potential complication of the procedure. Two patients developed lens opacities in 3 eyes after the procedure was performed for myopic astigmatism. The possible causes are discussed. This is not a dangerous complication as cataract extraction is easily achieved if necessary. However, it is undesirable and further research is required to assess the long-term incidence, causes, and ways to prevent its occurrence.

Adult↗
PubMed1999

Fluorescence microscopy of mycobacteria in pleural effusions.

The diagnostic advantage of fluorescence microscopy (FM) of Papanicolaou-stained cytological specimens obtained by bronchoscopy has been described previously. This study was designed to evaluate the method's diagnostic benefit in cytological preparations of pleural effusions in cases of active pulmonary tuberculosis. In contrast to bronchial material there is no advantage in cytological evaluation of pleural effusions by FM.

Humans↗
PubMed1998

Staar Collamer posterior chamber phakic intraocular lens to correct myopia and hyperopia.

PURPOSE: To evaluate the efficacy, safety, stability, and predictability of implanting a collagen polymer (Staar Collamer), posterior chamber phakic intraocular lens (IOL) to correct myopia and hyperopia. SETTING: Centre for Advanced Refractive Eye Surgery at the BMI Alexandra Hospital, Cheadle, Manchester, United Kingdom. METHODS: A Staar Collamer posterior chamber phakic IOL was implanted in 25 eyes of 14 patients with a mean age of 37.9 years (range 20 to 50 years). Seven patients were men and seven, women. Sixteen were myopic and 9, hyperopic. Before treatment, each patient had a thorough evaluation including refractive, general, ocular, and social and personal histories. The examination included visual acuity, refraction, tonometry, topography, biometry, biomicroscopy, pupil size in dim illumination, and posterior segment evaluation by a vitreoretinal specialist. Patients were informed about the surgical process and expected outcome, their own expectations were discussed, and their consent to surgery was obtained. Surgical implantation was performed through a less than 3.0 mm clear corneal sutureless incision using brief general anesthesia on a day-case surgical basis. RESULTS: At 3 months postoperatively, all eyes had a significant increase in uncorrected visual acuity, allowing all but two patients (three eyes) to manage most activities without spectacles. Adjustment by incisional corneal surgery was planned for undercorrected myopic eyes (n = 3). Pupil block glaucoma and pigment deposits occurred in one patient each. CONCLUSION: In this short-term study, the posterior chamber phakic IOL was predictable, safe, and efficacious in the correction of myopic and hyperopic refractive errors, with good refractive stability. Long-term follow-up is required to validate that the absence of significant complications in most patients is a lasting phenomenon.

Adult↗
PubMed1998

Applying the Sports Medicine Australia pre-exercise screening procedures: who will be excluded?

Recently Sports Medicine Australia (SMA) and the Australian Association for Exercise and Sport Science (AAESS) developed guidelines for pre-exercise screening and supervision of fitness testing, based on the American College of Sports Medicine (ACSM) system. The procedure involves classifying individuals into one of three risk groups (apparently healthy, at higher risk, with known disease). Using data collected in a 1992 survey of 2298 Australian adults aged 18-78 years conducted by the Department of the Arts, Sport, the Environment and Territories (DASET), we calculated the percentage of the general population falling within each risk group and therefore exclusion rates (ie the proportion of subjects who, it is recommended, would require medical clearance prior to exercise or exercise testing). The analysis of data found that between 43-73% of males and 44-61% of females would require clearance. A cost analysis suggests that a rigorous application of the SMA-AAESS guidelines would cost between $250 million and $1.2 billion each year. On the basis of the results, suggestions for reviewing the guidelines have been proposed.

Adult↗
PubMed1998

Altitude training at 2690m does not increase total haemoglobin mass or sea level VO2max in world champion track cyclists.

Haemoglobin mass (Hb mass), maximum oxygen consumption (VO2max), simulated 4000 m individual pursuit cycling performance (IP4000), and haematological markers of red blood cell (RBC) turnover were measured in 8 male cyclists before and after (A) 31 d of altitude training at 2690 m. The dependent variables were measured serially after altitude on d A3-4, A8-9 and A20-21. There was no significant change in Hb mass over the course of the study and VO2max at d A9 was significantly lower than the baseline value (79.3 +/- 0.7 versus 81.4 +/- 0.6 ml x kg(-1) x min(-1), respectively). No increase in Hb mass or VO2max was probably due to initial values being close to the natural physiological limit with little scope for further change. When the IP4000 was analysed as a function of the best score on any of the three test days after altitude training there was a 4% improvement that was not reflected in a corresponding change in VO2max or Hb mass. RBC creatine concentration was significantly reduced after altitude training, suggesting a decrease in the average age of the RBC population. However, measurement of reticulocyte number and serum concentrations of erythropoietin, haptoglobin and bilirubin before and after altitude provided no evidence of increased RBC turnover. The data suggest that for these elite cyclists any benefit of altitude training was not from changes in VO2max or Hb mass, although this does not exclude the possibility of improved anaerobic capacity.

Adult↗
PubMed1986

Reticular elicitation of hippocampal slow waves: common effects of some anxiolytic drugs.

Anxiolytic drugs share many of the common behavioural effects of septal and hippocampal lesions in animals. Gray attributes this to changes which the anxiolytics produce in septal generation of hippocampal rhythmical slow activity. However, lesions of the dorsal ascending noradrenergic bundle reproduce this electrophysiological effect of the anxiolytics while only reproducing part of the behavioural profile of the anxiolytics. The present paper reports what appears to be a second common effect of anxiolytic drugs on the generation of hippocampal slow waves which could underlie their behavioural effects. Freely moving rats, previously implanted with electrodes, received high frequency electrical stimulation of the midbrain reticular formation to elicit hippocampal rhythmic slow activity. The frequency of the slow waves produced increased linearly with increasing stimulation intensity as has been reported previously. A barbiturate (amylobarbitone, 15 mg/kg, i.p.) and three benzodiazepines (chlordiazepoxide, 5 mg/kg; diazepam, 5 mg/kg; alprazolam, 1 mg/kg) all decreased the slope of the voltage-frequency function and decreased overall frequency of slow waves produced. Two antipsychotic drugs (haloperidol, 0.2 mg/kg; chlorpromazine, 2 mg/kg) produced similar behavioural sedation to the anxiolytics but did not decrease either the slope of the voltage-frequency function nor the overall frequency of slow waves. The results show that these barbiturates and benzodiazepines produce a common reduction in the frequency of hippocampal rhythmical slow activity. Given the importance attached to slow waves in current theories of hippocampal function, it is possible that this electrophysiological effect could have some relation to the behavioural effects of these anxiolytic drugs. If the effect can be shown to generalize to other classes of anxiolytic drug it could reflect changes in the substrate for the common effects of anxiolytic drugs on behaviour.

Amobarbital↗
PubMedDate not supplied

Overcorrected radial keratotomy treated with posterior chamber phakic intraocular lens and laser thermal keratoplasty.

PURPOSE: Modern refractive surgery is effective in a large majority of cases in achieving a good first time result. Some attempts at correction, however, are less successful and require subsequent revision. METHODS: A case of secondary hyperopic astigmatism (+0.75 +1.50 x 45 degrees) is reported in a patient who had undergone radial keratotomy for myopia of -6.00 +0.75 x 90 degrees, 8 years previously. Preoperative uncorrected visual acuity was 20/120 improving to 20/20 with correction. Further refractive procedures were performed including arcuate keratotomy, posterior chamber phakic intraocular lens implantation and laser thermal keratoplasty to improve the uncorrected visual result. RESULTS: Final uncorrected visual acuity was 20/40, spectacle-corrected visual acuity was 20/20 with a manifest refraction of +0.50 +1.00 x 40 degrees. CONCLUSIONS: This case demonstrates how the consecutive application of several procedures can successfully refine an initially unsatisfactory refractive result. The potential for reduced predictability and additional complications with each procedure should not be forgotten.

Adult↗