Limbus- versus fornix-based conjunctival flaps in combined phacoemulsification and mitomycin C trabeculectomy surgery.

PURPOSE: The authors compared the effectiveness of limbus- and fornix-based conjunctival flaps in patients undergoing combined phacoemulsification, intraocular lens implantation, and mitomycin C trabeculectomy. METHODS: The authors conducted a retrospective review of the records of 52 consecutive eyes of 45 patients who underwent combined surgery with limbus- and fornix-based conjunctival flaps. All surgery was by done by one surgeon on predominantly white patients in a suburban glaucoma subspecialty practice. Seven patients had both limbus- and fornix-based surgery, permitting fellow eye comparisons in these patients. All patients had at least 6 months and a median of 17 months follow-up. None of the eyes that were operated on had undergone intraocular surgery previously. RESULTS: No clinically significant difference in postoperative pressure reduction, bleb survival, or visual acuity was seen between the fornix- and limbus-based groups. Results in the fellow eye comparison subgroups were similar. The mean intraocular pressure decreased from 20.4 mmHg before surgery to a mean of 12.4 mmHg at the last follow-up visit. Forty-seven (90.3%) of 52 eyes had a final best-corrected visual acuity of 20/ 40 or better. Forty eyes (76.9%) no longer needed antiglaucoma medications at the end of follow-up. Five eyes had intraoperative posterior capsule rupture; all of these occurred in the limbus-based group. Shallow serous choroidal effusions were more common in the fornix-based group, but none were clinically significant. No difference in postoperative astigmatism between the limbus- or fornix-based group was seen. Intraoperative pupilloplasty, synechialysis, or postoperative neodymium:YAG capsulotomy had no appreciable effect on final intraocular pressure or bleb survival. Endophthalmitis, aqueous misdirection, or hypotony maculopathy did not develop in any patient. CONCLUSION: The effectiveness of limbus- and fornix-based conjunctival flaps appears to be similar. The limbus-based technique may result in a higher incidence of posterior capsular rupture, but the safety of limbus- and fornix-based flaps is otherwise similar. Combined phacoemulsification and mitomycin C trabeculectomy appears to be safe and effective for treating selected patients with coexisting glaucoma and cataract.

Diminishment of respiratory sinus arrhythmia foreshadows doxorubicin-induced cardiomyopathy.

BACKGROUND: The development of a microcomputer-based device permits quick, simple, and noninvasive quantification of the respiratory sinus arrhythmia (RSA) during quiet breathing. METHODS AND RESULTS: We prospectively and serially measured the radionuclide left ventricular ejection fraction and the RSA amplitude in 34 cancer patients receiving up to nine monthly bolus treatments with doxorubicin hydrochloride (60 mg/m2). Of the eight patients who ultimately developed symptomatic doxorubicin-induced congestive heart failure, seven (87.5%) demonstrated a significant decline in RSA amplitude; five of 26 subjects without clinical symptoms of cardiotoxicity (19.2%) showed a similar RSA amplitude decline. On average, significant RSA amplitude decline occurred 3 months before the last planned doxorubicin dose in patients destined to develop clinical congestive heart failure. CONCLUSION: Overall, RSA amplitude abnormality proved to be a more specific predictor of clinically significant congestive heart failure than did serial resting radionuclide ejection fractions.

Sinusoidal fetal heart rate pattern during breathing is related to the respiratory sinus arrhythmia: a case report.

The sinusoidal fetal heart rate pattern is a phenomenon of elusive pathophysiologic features and uncertain clinical significance. We present a case of sinusoidal fetal heart rate that occurred in association with fetal breathing. The degree and type of synchrony between the sinusoidal fetal heart rate and breathing movements suggest that the sinusoidal fetal heart rate and the respiratory sinus arrhythmia are related phenomena.

Circadian rhythm and seasonal dependence in the toxicological response of mice to epirubicin.

Compared to doxorubicin, equimolar epirubicin toxicity is reduced by about 50% by the epimerization of a hydrogen and hydroxyl group at the 4' position of the anthracycline sugar moiety. The circadian timing of doxorubicin administration markedly affects its lethal and sub-lethal bone marrow and gut toxicities in mice, as well as the severity of its clinical toxicity. We tested whether the timing of administration of equitoxic epirubicin doses similarly affected the toxicological response in female CD2F1 mice. A large and highly reproducible effect of the circadian stage of administration was documented with best drug tolerance occurring during the first half of the daily rest (light) span of the animals. In addition to this circadian rhythm, a significant seasonal effect was found with significantly fewer deaths occurring after epirubicin was given in the Summer, as compared to the Winter. Safest circadian timing for epirubicin is statistically significantly earlier in the day than for doxorubicin, while their seasonal patterns are quite similar.

Methylene blue protects intestinal mucosa from free radical-mediated sublethal radiation damage.

Susceptibility of the intestine to radiation damage is a primary reason for the failure of external beam radiation to cure intra-abdominal cancer. High-dose irradiation causes intestinal denudation, fluid loss, and resultant shock. Simple and effective methods for protecting the intestine from irradiation damage are not available. Many biological effects of ionizing irradiation are caused by free radical intermediates. We have previously reported that many of the toxicities of doxorubicin, a classic free radical generating anticancer agent, are blocked by methylene blue pretreatment. We have now found that pretreatment with methylene blue protects rats from intestinal damage, as measured histologically and by quantitative stool blood determinations. Whereas the exact mechanisms of this protection remain elusive, we believe this method of modulating the therapeutic index of ionizing radiation deserves additional preclinical and clinical study.