Surgical indication and technical considerations in the management of benign brain stem gliomas

Summary The treatment of brain stem gliomas has evolved over the last few decades, reflecting advances in imaging (MR), microsurgical techniques and biological understanding. The aim of this chapter is to provide a preoperative classification for intrinsic brain stem lesions that will predict histopathology and biological behavior from the clinical syndrome and the MR appearance. Such a classification system may help selecting children with brain stem tumors that can benefit from surgery. Technical considerations, potential surgical complications, and the ways to avoid them are discussed.     

The role of routine culture for tuberculosis during bronchoscopy in a nonendemic area: analysis of 300 cases and review of the literature

BACKGROUND: Many centers routinely culture bronchoscopy samples for mycobacteria, even when tuberculosis (TB) is not strongly suspected. The value of this practice is poorly defined in areas with a low prevalence of TB. METHODS: A retrospective observational study was conducted in tertiary care, university-affiliated medical center and included 300 consecutive patients who underwent a bronchoscopy examination. The findings for acid-fast bacillus (AFB) staining and culture were reviewed, and data on demographic characteristics, presenting symptoms, old TB, autoimmune status, and chest x-ray results were collected from the files. RESULTS: The study included 175 men (58%) and 125 women, with a mean age of 62 +/- 25 years. Eight cultures (2.67%) grew mycobacteria: 4 (1.33%) Mycobacterium tuberculosis and 4 (1.33%) nontuberculous mycobacteria (NTM). Thus, the incidence of TB was 4 of 300 (1.33%) patients. There were no cases of positive AFB smear or culture in patients with atelectasis, pulmonary mass, or hemoptysis with normal chest x-ray. One of the 22 patients (5%) with diffuse pulmonary nodules had active TB as did 3 of the 134 patients (2.24%) with pulmonary infiltrates. All 4 patients with NTM had pulmonary infiltrates. The use of a cost-effective diagnostic strategy in our series, wherein testing would have been ruled out for patients without a clinical suspicion of TB and radiologic findings of a pulmonary mass (n = 107, 35.6%), would have saved the system US $5350. CONCLUSION: The findings highlight the importance of an effective strategy for routine TB cultures during bronchoscopy in patients from nonendemic areas in whom TB is not suspected, especially those with pulmonary mass.     

Statin efficacy and safety for lipid modification in apparently healthy male military aircrew

INTRODUCTION: Military aircrew men represent an elite group of relatively young, fit, and healthy people. The effectiveness of statin treatment in reducing low-density lipoprotein cholesterol (LDL-C) according to the current National Cholesterol Education Program (NCEP) guidelines, its safety, and compliance in this group of people has not yet been determined. METHODS: We prospectively evaluated 84 military aircrew men (mean age 43 +/- 7 yr) with LDL-C above the current NCEP guidelines. The patients were divided into two groups according to their coronary risk factors: Group 1, LDL-C goal < 160 mg x dL(-1); Group 2, LDL-C goal < 130 mg dL(-1). All patients received statins in addition to therapeutic lifestyle changes and were followed for a mean of 3 +/- 1 yr according to a simple flow chart. Lipoprotein levels, liver function tests, creatinine phosphokinase, and subjective adverse reactions were checked periodically. RESULTS: LDL-C significantly declined by 32% (p < 0.0001) within the first month of treatment and 99% of subjects achieved their LDL-C goal within 114 +/-35 d from statin therapy initiation. The Framingham estimated 10-yr coronary risk showed a reduction at an average of 12 mo after statin therapy initiation from a baseline value of 6.54% to 3.95% (p = 0.003). No subjects were grounded or disqualified from duty, there were no cardiovascular events during follow-up, and compliance to therapy was high [82/84 (98%)]. DISCUSSION: Statin treatment in this highly select, relatively young group of aircrew men significantly and safely lowered LDL-C cholesterol levels.     

Case selection for apical surgery: a retrospective evaluation of associated factors and rational

Endodontic failures associated with poor quality of endodontics respond favorably to retreatment. Nevertheless, under certain clinical conditions, apicoectomy should be the preferred procedure. A retrospective survey of 200 roots that were referred for apical surgery revealed that 83% of the roots were inadequately obturated, including 8.5% with no root canal filling at all. In 49 of the roots in this group (24.5% of the referred cases) nonsurgical retreatment was judged by an endodontist as either impossible or improbable because it might jeopardize the root integrity. Retreatment should have been the preferred treatment modality for the rest of the group, provided that coronal restorations could be safely bypassed or removed. Posts were found in 63 of these teeth, however 35 of them were either short or loosely fitting and could safely be removed. The rest of the posts were longer than 5 mm, which might have presented a problem if their removal was attempted. In 45% of the 200 cases in the present study, surgical intervention was justified. The rest of the cases (55%) should have either been subjected to a follow-up (10.5%) or retreated nonsurgically by a skilled endodontist (44.5%). These results indicate that referring dentists may not appreciate the retreatment possibilities offered by modern endodontics, and they emphasize the need for a shift of concept: endodontists should be involved in the decision making before referring a patient to surgery.     

Task switching after cerebellar damage

The authors of this study investigated task switching following cerebellar damage. The study group consisted of 7 children and adolescents (M age=13.8 years) who underwent surgical removal of a benign posterior fossa tumor. They were tested at a sufficient interval after surgery (M lag=6.13 years) for restoration of normal cognitive skills and intelligence. Although all showed normal learning of the task compared with control participants, when rapid behavioral changes were required (short preparation time), they exhibited behavioral rigidity manifested by enhanced switching cost. These results are in line with another study on serial reaction time with the same patients (A. Berger et al., in press). They have important implications for our understanding of the cognitive sequelae of early cerebellar damage as well as the involvement of the cerebellum in task switching.     

Cancer detection from stained biopsies using high-speed spectral imaging

The escalating demand for diagnosing pathological biopsies requires the procedures to be expedited and automated. The existing imaging systems for measuring biopsies only measure color, and even though a lot of effort is invested in deep learning analysis, there are still serious challenges regarding the performance and validity of the data for the intended medical setting. We developed a system that rapidly acquires spectral images from biopsies, followed by spectral classification algorithms. The spectral information is remarkably more informative than the color information, and leads to very high accuracy in identifying cancer cells, as tested on tens of cancer cases. This was improved even more by using artificial intelligence algorithms that required a rather small training set, indicating the high level of information that exists in the spectral images. The most important spectral differences are observed in the nucleus and they are related to aneuploidy in tumor cells. Rapid spectral imaging measurement therefore can bridge the gap in the machine-aided diagnostics of whole biopsies, thus improving patient care, and expediting the treatment procedure.