Quantitative evaluation of headache severity before and after endoscopic transsphenoidal surgery for pituitary adenoma.

OBJECT The relationship between headaches, pituitary adenomas, and surgical treatment of pituitary adenomas remains unclear. The authors assessed the severity and predictors of self-reported headaches in patients referred for surgery of pituitary adenomas and evaluated the impact of endoscopic transsphenoidal surgery on headache severity and quality of life (QOL). METHODS In this prospective study, 79 patients with pituitary adenomas underwent endoscopic transsphenoidal resection and completed the Headache Impact Test (HIT-6) and the 36-Item Short Form Health Survey (SF-36) QOL questionnaire preoperatively and at 6 weeks and 6 months postoperatively. RESULTS Preoperatively, 49.4% of patients had mild headache severity, 13.9% had moderate severity, 13.9% had substantial severity, and 22.8% had intense severity. Younger age and hormone-producing tumors predisposed greater headache severity, while tumor volume, suprasellar extension, chiasmal compression, and cavernous sinus invasion of the pituitary tumors did not. Preoperative headache severity was found to be significantly associated with reduced scores across all SF-36 QOL dimensions and most significantly associated with mental health. By 6 months postoperatively, headache severity was reduced in a significant proportion of patients. Of the 40 patients with headaches causing an impact on daily living (moderate, substantial, or intense headache), 70% had improvement of at least 1 category on HIT-6 by 6 months postoperatively, while headache worsened in 7.6% of patients. The best predictors of headache response to surgery included younger age, poor preoperative SF-36 mental health score, and hormone-producing microadenoma. CONCLUSIONS The results of this study confirm that surgery can significantly improve headaches in patients with pituitary adenomas by 6 months postoperatively, particularly in younger patients whose preoperative QOL is impacted. A larger multicenter study is underway to evaluate the long-term effect of surgery on headaches in this patient group.

The relationship between naming reaction time and functional MRI parameters in Broca's area.

We examined the correlation between behavioural reaction time and functional imaging parameters of the blood oxygenated level dependent (BOLD) response in Broca's Area during a word identification task, and whether the correlation [Magnetic Resonance Imaging 22 (2004) 451-455] varies as a function of four stimulus types: regular words (REGs) (e.g., hint), irregular words (IRRs) (e.g., pint), nonwords (NWs) (e.g., bint), and pseudohomophones (PHs) (e.g., pynt). Participants named letter strings aloud during a functional magnetic resonance imaging study. Naming reaction times were recorded during regular gaps in image acquisition, and BOLD parameters were extracted via a Tikhonov regularized BOLD analysis technique. The results revealed that only PH reaction times were correlated with BOLD width, providing evidence that Broca's area supports phonetic decoding accompanied with phonological lexical access. In addition, we advanced the development of equation-based models of cognitive behaviour and neurophysiology, whereby we showed that the relationship of mathematical independence that exists for predicting REG accuracy, given IRR and NW or PH naming accuracy, was present for naming reaction time, BOLD width, BOLD time to peak, and BOLD intensity. Therefore, we provide converging behavioural and neuroanatomical evidence for a mathematically independent relationship between sight vocabulary and phonetic decoding systems, consistent with a dual-route model of reading.

Tumor promotion by caspase-resistant retinoblastoma protein.

The retinoblastoma (RB) protein regulates cell proliferation and cell death. RB is cleaved by caspase during apoptosis. A mutation of the caspase-cleavage site in the RB C terminus has been made in the mouse Rb-1 locus; the resulting Rb-MI mice are resistant to endotoxin-induced apoptosis in the intestine. The Rb-MI mice do not exhibit increased tumor incidence, because the MI mutation does not disrupt the Rb tumor suppressor function. In this study, we show that Rb-MI can promote the formation of colonic adenomas in the p53-null genetic background. Consistent with this tumor phenotype, Rb-MI reduces colorectal epithelial apoptosis and ulceration caused by dextran sulfate sodium. By contrast, Rb-MI does not affect the lymphoma phenotype of p53-null mice, in keeping with its inability to protect thymocytes and splenocytes from apoptosis. The Rb-MI protein is expressed and phosphorylated in the tumors, thereby inactivating its growth suppression function. These results suggest that RB tumor suppressor function, i.e., inhibition of proliferation, is inactivated by phosphorylation, whereas RB tumor promoting function, i.e., inhibition of apoptosis, is inactivated by caspase cleavage.