Device fixation in cochlear implantation: is bone anchoring necessary?

OBJECTIVES/HYPOTHESIS: To compare complication rates between patients whose cochlear implants were secured by a bony tie-down technique versus those secured by a periosteal tie-down technique. STUDY DESIGN: A retrospective review of 302 consecutive patients undergoing cochlear implantation (327 implants), including both adults and children, at a single institution by a single surgeon. METHODS: Cochlear implantation was performed in the standard fashion with bony securement of the device in the first subset of patients. The surgical technique was then modified to exclude the bony tie-down step in favor of a periosteally placed suture tie-down in the next subset of patients. The patient's medical records were then reviewed to determine complications, which were then compared between groups using chi(2) testing. RESULTS: The overall complication rate for the periosteally secured cochlear implant subset was 9.5%, with no significant difference noted when compared to the 12.2% overall complication rate seen with the bone-secured implants. Minor complication rates were 9.5% versus 8.1%, respectively, with major complications occurring in 0% versus 4.1% of periosteally secured versus bone-secured devices. There were no statistical differences between groups for major, minor, or any specific complications. There were no cases of device migration. CONCLUSIONS: Cochlear implant devices may be secured in place with periosteally anchored sutures in lieu of bone-anchored sutures without any significant increases in perioperative complications.

Gold laser tonsillectomy--a safe new method.

OBJECTIVES: To determine if Gold laser tonsillectomy is an acceptably safe method of removing tonsils by comparing its complication rates to other established methods, namely Coblation tonsillectomy and cold steel dissection tonsillectomy. STUDY DESIGN: A retrospective review of 748 consecutive patients, ages 2-18, undergoing tonsillectomy at a pediatric teaching institution. METHODS: Tonsillectomy with or without adenoidectomy was performed utilizing either the Gold laser (n=435), Coblation device (n=153), or by cold steel dissection (n=160) between August 2005 and August 2007. Hospital charts were then reviewed to determine the rates of post-tonsillectomy hemorrhage and dehydration requiring hospital admission. RESULTS: In the Gold laser group there were 7 bleeding events (1.61%) and 7 dehydration admissions (1.61%). The Coblation group had 9 bleeding events (5.88%) and 1 dehydration admission (0.65%). The cold steel group had 1 bleed (0.63%) and 2 dehydration admissions (1.25%). The hemorrhage rate associated with Gold laser tonsillectomy was statistically equivalent to cold steel dissection (p=0.3710) and significantly lower than in our Coblation control group (p=0.0286). CONCLUSIONS: Tonsillectomy by means of the Gold laser can be safely performed in the pediatric population.

Essential role of STAT3 in body weight and glucose homeostasis.

STAT3 is a ubiquitous transcription factor that is indispensable during early embryogenesis. To study the functions of STAT3 postnatally, we generated conditional STAT3-deficient mice. To that end, STAT3(lox/lox) mice were crossed with mice expressing Cre under the control of rat insulin II gene promoter (RIP-Cre mice). Immunohistochemical and Western blot analyses showed that STAT3 is deleted from beta cells in the islets of Langerhans. Genomic DNA PCR revealed that STAT3 deletion also occurred in the hypothalamus. Hypothalamic Cre expression was further confirmed by crossing RIP-Cre/STAT3(lox/lox) mice with the ROSA26 Cre reporter strain and staining for lacZ activity. Double immunohistochemical staining confirmed that deletion of STAT3 occurred in leptin receptor (OB-Rb isoform)-positive neurons. RIP-Cre/STAT3(lox/lox) mice are mildly hyperglycemic and hyperinsulinemic at the time of weaning, become hyperphagic immediately after weaning, and exhibit impaired glucose tolerance. Body weight, body fat, and mRNA and protein levels of leptin are all significantly increased in RIP-Cre/STAT3(lox/lox) mice. Administration of recombinant leptin by intracerebroventricular infusion failed to cause complete loss of body fat in RIP-Cre/STAT3(lox/lox) mice. Transplantation of wild-type islets into RIP-Cre/STAT3(lox/lox) mice also failed to decrease adiposity or to correct other abnormalities in these mice. These data thus suggest that loss of STAT3 in the hypothalamus caused by RIP-Cre action likely interferes with normal body weight homeostasis and glucose metabolism.