PATCHING RETINAL BREAKS WITH HEALAFLOW IN 27-GAUGE VITRECTOMY FOR THE TREATMENT OF RHEGMATOGENOUS RETINAL DETACHMENT.

PURPOSE: To report the surgical outcomes of primary rhegmatogenous retinal detachment (RRD) repaired by 27-gauge pars plana vitrectomy combined with Healaflow patch and air tamponade. METHODS: In an initial vitro experiment, we observed and compared the dissolution and displacement of the dispersion spots of 0.05-mL Healaflow and sodium hyaluronate. We then performed a prospective, interventional cohort study on 38 eyes in 37 consecutive patients with primary rhegmatogenous retinal detachment. All eyes underwent pars plana vitrectomy combined with Healaflow patch and air tamponade; the postoperative period did not involve prone positioning. The primary and final anatomical attachment rate, best-corrected visual acuity, and intraoperative and postoperative complications were evaluated. RESULTS: In the in vitro experiment, the viscoelastic Healaflow remained adherent with no change in the size of the area; however, the control dissolved completely in the balance solution. The patient study included 16 women (43.2%) and 21 men (56.8%) (mean age, 59.5 ± 9.5 years; mean follow-up period, 8.9 ± 3.8 months). A single break was present in 21 (55.3%) and 2 to 5 breaks in 17 cases (44.8%). The macula was involved in 25 (65.8%) and attached in 13 cases (34.2%) intraoperatively. Initial reattachment was achieved in 37 (97.4%) and final reattachment in 38 cases (100%). In one case (2.6%), the macula redetached because of failure of the chorioretinal scar to develop around the treated break. Mean preoperative and postoperative best-corrected visual acuities were 1.02 ± 0.82 logarithm of the minimum angle of resolution (median Snellen acuity: 20/125, range: 20/20,000-20/20) and 0.23 ± 0.17 logarithm of the minimum angle of resolution (median Snellen acuity: 20/32, range: 20/100-20/20), respectively (P < 0.001). Intraocular pressure was elevated transiently in 28 eyes (73.7%). There were no other intraoperative complications or postoperative scleral incision leakage. CONCLUSION: A 27-gauge pars plana vitrectomy combined with Healaflow patch, and air tamponade results in a high reattachment rate in the treatment of rhegmatogenous retinal detachment. Thus, patients can benefit from early visual recovery and less complications.

Methyl parathion increases neuronal activities in the rat locus coeruleus.

Exposure to organophosphate insecticides induces undesirable behavioral changes in humans, including anxiety and irritability, depression, cognitive disturbances and sleep disorders. Little information currently exists concerning the neural mechanisms underlying such behavioral changes. The brain stem locus coeruleus (LC) could be a mediator of organophosphate insecticide-induced behavioral toxicities since it contains high levels of acetylcholinesterase and is involved in the regulation of the sleep-wake cycle, attention, arousal, memory, and pathological processes, including anxiety and depression. In the present study, using a multi-wire recording technique, we examined the effects of methyl parathion, a commonly used organophosphate insecticide, on the firing patterns of LC neurons in rats. Systemic administration of a single dose of methyl parathion (1 mg/kg, i.v.) increased the spontaneous firing rates of LC neurons by 240% but did not change the temporal relationships among the activities of multiple LC neurons. This dose of methyl parathion induced a 50% decrease in blood acetylcholinesterase activity and a 48% decrease in LC acetylcholinesterase activity. The methyl parathion-induced excitation of LC neurons was reversed by administration of atropine sulfate, a muscarinic receptor antagonist, indicating an involvement of muscarinic receptors. The methyl parathion-induced increase in LC neuronal activity returned to normal within 30 min while the blood acetylcholinesterase activity remained inhibited for over 1 h. These data indicate that methyl parathion treatment can elicit excitation of LC neurons. Such excitation could contribute to the neuronal basis of organophosphate insecticide-induced behavioral changes in human.