James H Merritt | PubMed Health

PubMed2003

Interpolated conjunctival pedicle flaps for the treatment of exposed glaucoma drainage devices.

OBJECTIVE: To describe an alternative method to repair exposed glaucoma drainage devices (GDDs) when conventional attempts have failed. METHODS: Four eyes, from 3 patients, with severe ocular surface disease were included in the study. All eyes had previously received a Baerveldt GDD for uncontrollable intraocular pressure and postoperatively had exposed GDDs. The conjunctival defects were unrepairable with a scleral patch or pericardium, conjunctival advancement, or a conjunctival patch graft. Two eyes had chemical burns, one eye had extensive scarring from multiple surgical procedures, and one patient had rheumatoid arthritis. Each patient provided informed consent, and was given the option of removing the GDD and undergoing diode cyclophotocoagulation or attempting to save the GDD by a conjunctival pedicle flap. An interpolated conjunctival pedicle flap was taken from the cul-de-sac (fornix). The conjunctiva and Tenon capsule were incised radially to the tube, rotated from the fornix at a 90 degrees angle, and sutured to the remaining healthy conjunctiva to cover the exposed tube. RESULTS: Postoperatively, all eyes had vascularized flaps that showed viable tissue. All eyes retained the GDDs, and the intraocular pressure has been under control during follow-up (7, 13, 25, and 27 months). CONCLUSION: Interpolated conjunctival pedicle flaps seem to be a viable alternative to repairing exposed GDDs when other methods are impractical or impossible.

Aged↗

PubMed2003

Radiofrequency fields and teratogenesis.

Experimental studies that sought teratologic effects or developmental abnormalities from exposure to radiofrequency electromagnetic fields (RFEMF) in the range 3 kHz-300 GHz are critically reviewed for their possible consequences on human health. Those studies were conducted on beetles, birds, rodents, and nonhuman primates. Collectively, those experimental studies indicate that teratologic effects can occur only from exposure levels that cause biologically detrimental increases in body temperature. No reliable experimental evidence was found for nonthermal teratologic effects; rodents, mouse fetuses, and perinatal mice are more susceptible to such effects than rats. The primary confirmed effect in rats at high RFEMF levels was initial weight deficits in fetuses and neonates that decreased with infant growth. More generally from findings with pregnant mammals, exposures at RFEMF levels far higher than those permitted under the IEEE human exposure guidelines are necessary to reach or exceed cited experimental thresholds for maternal temperature increases. Some results indicated that the levels necessary to cause such effects in pregnant mammals could exceed those lethal to the dams. In a behavioral study of squirrel monkeys, no effects were observed on usual dam-offspring interactions or EEGs, but unexpected deaths of a number of offspring had occurred. However, this finding was not confirmed in a study solely on infant death using a larger number of subjects for greater statistical validity. Also reviewed were epidemiologic studies of various human populations considered to have been chronically exposed to environmental levels of RFEMF. Early studies on the incidence of congenital anomalies yielded no credible evidence that chronic exposure of pregnant women or of fathers exposed to RFEMF from nearby sources at levels below those guidelines would cause any anomalies in their offspring. The findings of studies on pregnancy outcomes of female physiotherapists occupationally exposed while treating patients with RFEMF were mixed, but taken collectively, the findings were negative.

Abnormalities, Radiation-Induced↗