Operating environment for awake brain surgery - Choice of tests.

INTRODUCTION: The indication for awake brain surgery depends on a prerequisite, i.e. recognition that the brain area concerned is truly eloquent, and identification of one or more functions that must be preserved. These functions are determined preoperatively in collaboration with the patient, and neuropsychological tests considered to be the most relevant are performed in the operating room according to each team's technical preferences. OPERATING ENVIRONMENT: The neurosurgeon must choose transfer equipment considered to be relevant. Although a minimal technological environment is an option, a surgical team with great human wealth is essential, composed of specialized personnel with complementary skills. CHOICE AND IMPLEMENTATION OF INTRAOPERATIVE TESTS: The choice of intraoperative tests, which can be relatively simple for certain primary functions, can be much more difficult for high-level cognitive functions. No consensus has been reached concerning these tests, which must therefore be selected on an individual basis. Intraoperative testing must be based on preoperative multidisciplinary decisions made jointly by the neurosurgeon, neurologist, speech therapist and neuropsychologist. CONCLUSIONS: Numerous operating tools and technology transfers are available for neurosurgical teams performing awake brain surgery but none - or very few - of them constitutes a mandatory prerequisite. In contrast, the transition from the concept of eloquent brain area to that of brain functions that must be preserved requires highly skilled multidisciplinary human resources. This goal will be more likely achieved in centers highly specialized in functional oncological neurosurgery.

Study of accessory deep peroneal nerve motor conduction in a population of healthy subjects.

AIM OF THE STUDY: The short extensor muscle of the toes (extensor digitorum brevis) is innervated by the deep peroneal nerve (DPN) but can also receive innervation from an accessory deep peroneal nerve (ADPN), a branch of the superficial peroneal nerve (SPN). PATIENTS AND METHODS: We conducted a systematic electrophysiological study of the DPN and ADPN in 200 healthy subjects (400 legs). RESULTS: We found the presence of an ADPN in 13.5% of the subjects (8.5% of the legs). On average, ADPN amplitudes and motor potential areas were one-fifth of those for the corresponding DPN. Without this systematic search, most of the ADPN would not have been detected. Comparative study of electrophysiological parameters in patients with and without ADPN showed a significantly higher (P<0.0001) DPN motor potential area ratio (distal/proximal ratio) in subjects without an ADPN. CONCLUSION: Even though electrophysiological identification of the ADPN is generally not easy (in simple DPN motor conduction studies), the nerve can sometimes be clinically symptomatic (ankle pain). Evaluation of the DPN motor potential area ratio (distal/proximal ratio) heightens the detection of ADPN.

[Muscular metastasis]. / Les métastases des muscles striés.

INTRODUCTION: Neoplasia is quite rare in myology. For unknown reasons, muscular metastasis are rarely described in cancer. METHOD: Our work was a retrospective study with analysis of the medical literature and the presentation of one case of muscular metastasis revealed by a limitation of mouth opening in a 58-year-old Caucasian man (metastatic infiltration of the right pterygoid muscle secondary to a poorly differentiated adenocarcinoma of the lower third of the esophagus). RESULTS: In addition to our case, we found 174 cases of cancer with muscular metastasis. Most of cases were observed in males (male/female ratio=2/1). The mean age at onset was 58.5 years (range: 13-89 years). The muscular metastasis were rarely found before the diagnosis of cancer (only in 37%), and usually appeared during disease progression, with other (extramuscular) metastases in 60% of cases. Prognosis was poor with less than 2.5% survival beyond 72 months. In most cases, muscular metastasis presented as a unique (78%), painful (61%) and palpable (63%) muscular mass, even if other asymptomatic muscular metastasis could be present. The mean localization of muscular metastasis was the lower limbs (46%), particularly in the proximal part (38% of all the muscular metastasis). The most frequent cancers were localized in lung, urinary tract, digestive tract and genital tract. When the muscular biopsy showed an "adenocarcinoma", in men the primitive cancers were localized in the digestive tract (35%), kidney (20%), and lung (18%) and in women, the genital tract and breast (23.5%). When the muscular biopsy showed a "squamous-cell carcinoma", in men the primitive cancers were localized in the lung (81%) and in women the cervix (64%). CONCLUSION: These results highlight the importance of searching for muscular metastasis in patients with a focal, painful and palpable muscular mass. The muscular biopsy and immunohistochemical data can be helpful in identifying the primary cancer.