Use of intraoperative ultrasound for localizing tumors and determining the extent of resection: a comparative study with magnetic resonance imaging.

A prospective study of 70 patients with intraparenchymal brain lesions (36 gliomas and 34 metastases) was performed to evaluate the efficacy of intraoperative ultrasound (IOUS) in localizing and defining the borders of tumors and in assessing the extent of their resection. Eighteen of the 36 glioma patients had no previous therapy. All of these 18 tumors were well localized by IOUS; margins were well defined in 15 and moderately defined in three. The extent of resection was well defined on IOUS in all 18 patients, as confirmed by measurements taken on postoperative magnetic resonance (MR) images (p = 0.90). The remaining 18 patients with gliomas had undergone previous surgery and/or radiation therapy; five had recurrent tumors and 13 had radiation-induced changes. The extent of resection of the recurrent tumors was well defined in all but one patient, as confirmed by postoperative MR imaging. The extent of resection was poorly defined in all 13 patients whose pathology showed radiation effects. All 34 metastatic lesions were well localized and had well-defined margins. In addition, IOUS accurately determined the extent of resection in all cases, the results were confirmed with postoperative MR imaging. In conclusion, IOUS is not only helpful in localizing and defining the margins of gliomas and metastatic brain lesions, it also accurately determines the extent of resection, as confirmed by postoperative MR imaging. This assessment does not apply, however when the lesion is due primarily to radiation effect.

Tobacco, alcohol, and illicit drug use among Mexican-American and non-Hispanic white high school students.

This study examined the prevalence, age of initiation, and pattern of substance use among 1,617 Mexican-American and non-Hispanic White high school students residing within the same geographic community. Ethnic differences were present for current smoking, having used alcohol in the past month, "heavy drinking" per occasion, and ever used marijuana. Age of initiation of substance use and the pattern of use was similar for the two ethnic groups. Future research needs to determine if the progression of initiation represents a sequence of initiation, identify factors that influence movement along the sequence, and determine if there are ethnic differences.

Colorectal carcinoma and brain metastasis: distribution, treatment, and survival.

BACKGROUND: Brain metastasis from colorectal cancer is rare. The present study reports the nature of this disease and analyzes factors correlated with survival in patients harboring such disease. PATIENTS AND METHODS: One hundred patients diagnosed between 1980 and 1994 with metastatic brain tumors secondary to colorectal adenocarcinoma were retrospectively reviewed. Of these patients, 36 underwent surgery, 57 underwent radiotherapy alone, and the remaining seven received steroids. RESULTS: The most common primary sites were the sigmoid colon and rectum (65%). Brain metastases with concomitant liver and/or lung metastases were seen more frequently than brain metastases alone. The median interval between the diagnosis of primary cancer and the diagnosis of brain metastasis was 26 months (95% confidence interval = 22-30). The median survival time after the diagnosis of brain metastasis was 1 month for patients who received only steroids, 3 months for those who received radiotherapy (p = 0.1), and 9 months for those who underwent surgery (p < 0.0001). The extent of noncerebral systemic disease was not correlated with survival (p > 0.05), but early onset of brain metastasis was significantly associated with poor prognosis (p = 0.04). CONCLUSION: Surgical removal of colorectal metastatic brain lesions results in significantly increased survival time, regardless of the status of the noncerebral systemic disease.

Reliability and validity of computer-assisted estimates of Tanner-Whitehouse skeletal maturity (CASAS): comparison with the manual method.

Three observers rated 57 X-rays from normal healthy children in Project HeartBeat! twice each by CASAS, the computer-assisted version of the TW2 RUS bone age method. Differences between duplicates of individual bone ratings which reached or exceeded 1.0 unit (or 1 stage) were 5% within observer and 8% between observers for CASAS, and 17 and 33%, respectively, for the unassisted MANUAL method. In children followed longitudinally, CASAS scores increased much more steadily than MANUAL scores, largely because the bones were rated, in the former system, on a continuous rather than a discrete-integer scale. We conclude that CASAS is a more reliable and probably a more valid estimator of skeletal maturity than the MANUAL version of the TW2 RUS method.