Biomedical subjects

B J T Vote

Publications and source records attributed to B J T Vote.

3 recordsLinked to original sources

PubMed2004

The evaluation of a humidifying device for vitreoretinal surgery.

AIM: To study the feasibility of humidifying air during vitreoretinal surgery and measure the water content of air before and after intraocular transit. METHODS: The absolute water content of air was measured in a series of six eyes undergoing fluid-air exchange during macular hole surgery. Infrared absorption spectroscopy was used to determine the water content of the air infusing and exiting each eye. After baseline measurements for each eye were recorded, a second fluid-air exchange was performed and the effect of humidifying the air infusion was documented. The humidifying device used in this study was a prototype adapted from a commercially available respiratory humidifier and enables humidified air to be delivered at a controlled temperature. RESULTS: The water content of air increased following intraocular transit, implying dehydration occurs from the intraocular surfaces. For a standard airline infusion the mean increase in water content of air egressing from an eye was 13.4 mg/l. Humidifying the air reduced the rate of water loss by nearly 90%. CONCLUSIONS: Significant water losses can occur from eyes undergoing fluid-air exchange. Humidifying the infused air can substantially reduce the dehydrating effect during an air exchange. This outcome may have a beneficial effect in reducing cataract formation and visual field defects associated with macular hole surgery.

Air↗

PubMed2002

Humidity devices in vitreoretinal surgery.

PURPOSE: To assess a humidity device used in vitreoretinal surgery. METHODS: Infrared absorption spectroscopy analysis of absolute water content (absolute humidity) was determined for a typical vitreoretinal air infusion line with and without the humidifying device. A variety of experimental laboratory conditions were utilized and designed to mimic those found in the operating room. The effect on physical parameters, such as flow rates and resistance to flow, were also determined. RESULTS: While large bore infusion (LBI) lines had a negligible effect on flow rate and resistance to flow (reduction in infusion pressure), the standard 20 G infusion line (SI) reduced flow rate and infusion pressure by approximately 25%. When used together, the humidifying device and SI reduced flow rate and infusion pressure by one third. The humidifying device was found to add 6.5 mg/L water content to the air infusion line system. Typical operating room (OR) air contains 9.5 mg/L water content, and 43.876 mg/L water content is required to saturate air at body temperature. CONCLUSION: To eliminate dehydration as a cause of intraocular morbidity, one must first saturate the infused air. If the visual field defects and other complications are eliminated, this would be good evidence for saturating infused air. As infusion pressure (flow rate) influences dehydration rate, unless saturated air is used, infusion pressure cannot be considered an independent variable in the analysis of field defects.

Body Temperature↗

PubMed2002

Anti-inflammatory fibrosis suppression in threatened trabeculectomy bleb failure produces good long term control of intraocular pressure without risk of sight threatening complications.

AIMS: To determine the long term outcome of systemic anti-inflammatory fibrosis suppression in cases of threatened trabeculectomy bleb failure in open angle glaucoma. METHODS: This prospective non-comparative case series followed 77 eyes of 63 patients which showed signs of threatened early bleb failure and were treated with oral anti-inflammatory fibrosis suppression of prednisone, a non-steroidal anti-inflammatory agent, and colchicine taken for a mean period of 6 weeks, in addition to standard postoperative topical treatment, for a mean follow up of 6 years. RESULTS: Trabeculectomy with anti-inflammatory fibrosis suppression controlled the IOP at < or =21 mm Hg with a probability of 0.91 (95% CI: 0.81 to 1.0) at 8 years and 0.89 (95% CI: 0.56 to 1.1) at 12 years. There were no reported cases of endophthalmitis, hypotonous maculopathy, late bleb leak, or serious systemic side effects. CONCLUSION: Anti-inflammatory fibrosis suppression provided good control of bleb fibrosis without risk of sight threatening complications in a patient group at high risk of bleb failure.

Adult↗