Superficial temporal artery injury and delayed post-cranioplasty infection.

OBJECTIVE: Complications after cranioplasty after decompressive craniectomy (DC) have been reported to be as high as 40%. The superficial temporal artery (STA) is at substantial risk for injury in standard reverse question-mark incisions that are typically used for unilateral DC. The authors hypothesize that STA injury during craniectomy predisposes patients to post-cranioplasty surgical site infection (SSI) and/or wound complication. METHODS: A retrospective study of all patients at a single institution who underwent cranioplasty after decompressive craniectomy and who underwent imaging of the head (computed tomography angiogram, magnetic resonance imaging with intravenous contrast, or diagnostic cerebral angiography) for any indication between the two procedures was undertaken. The degree of STA injury was classified and univariate statistics were used to compare groups. RESULTS: Fifty-four patients met inclusion criteria. Thirty-three patients (61%) had evidence of complete or partial STA injury on pre-cranioplasty imaging. Nine patients (16.7%) developed either an SSI or wound complication after cranioplasty and, among these, four (7.4%) experienced delayed (>2 weeks from cranioplasty) complications. Seven of 9 patients required surgical debridement and cranioplasty explant. There was a stepwise but non-significant increase in post-cranioplasty SSI (STA present: 10%, STA partial injury: 17%, STA complete injury: 24%, P=0.53) and delayed post-cranioplasty SSI (STA present: 0%, STA partial injury: 8%, STA complete injury: 14%, P=0.26). CONCLUSIONS: There is a notable but statistically non-significant trend toward increased rates of SSI in patients with complete or partial STA injury during craniectomy.

Oxidation of controlled low-temperature vacuum dehydrated and freeze-dried beef and pork.

Processes of freeze-drying and controlled low-temperature vacuum dehydration were used for drying beef and pork. The drying-time of controlled low-temperature vacuum dehydration was less than that of freeze-drying. Monolayer moisture contents and surface areas of freeze-dried products were higher than those of products dried by controlled lowtemperature vacuum dehydration. The contents of myoglobin decreased and lipid oxidation increased during storage, and more marked effects were seen at higher storage temperatures. Myoglobin degradation in freeze-dried beef and pork was greater than in samples dried by controlled low-temperature vacuum dehydration.

Prostaglandin E2 does not inhibit metamorphosis of tadpole tails in tissue culture.

Tadpoles excrete prostaglandin E2 (PGE2) in oral mucus and at the same time trap food particles on oral mucus during feeding. Wassersug (1986) suggested that orally excreted and then ingested PGE2 might inhibit premature metamorphosis in anurans. We have tested to see whether PGE2 inhibits thyroid hormone-induced metamorphosis of tadpole tails in tissue culture. It does not. It is still possible that an endocrinologically active component of oral mucus plays a regulatory role in metamorphosis, but it may not act directly on tail tissue or it may not even be PGE2.