Frequency and topography in monkey electroencephalogram during action observation: possible neural correlates of the mirror neuron system.

The observation of actions executed by others results in desynchronization of electroencephalogram (EEG) in the alpha and beta frequency bands recorded from the central regions in humans. On the other hand, mirror neurons, which are thought to be responsible for this effect, have been studied only in macaque monkeys, using single-cell recordings. Here, as a first step in a research programme aimed at understanding the parallels between human and monkey mirror neuron systems (MNS), we recorded EEG from the scalp of two monkeys during action observation. The monkeys were trained to fixate on the face of a human agent and subsequently to fixate on a target upon which the agent performed a grasping action. We found that action observation produced desynchronization in the 19-25 Hz band that was strongest over anterior and central electrodes. These results are in line with human data showing that specific frequency bands within the power spectrum of the ongoing EEG may be modulated by observation of actions and therefore might be a specific marker of MNS activity.

[Echography in gynecologic emergencies]. / L'ecografia nelle urgenze ginecologiche.

The authors report their experience with US in gynecologic emergencies through a retrospective study on 105 patients presenting with acute abdomen of suspected gynecologic nature. The series included 3 groups of patients: Group I: 59 patients all submitted to immediate surgery. The following pathologic conditions were observed: ectopic pregnancy (23 cases), torsion or hemorrhage from ovarian cysts (13 cases), pyosalpinx or tubo-ovarian abscess (9 cases), torsion of pedunculated uterine leiomyoma (7 cases), intraperitoneal bleeding from hemorrhagic corpus luteum (6 cases), hematocolpos and hematometra from imperforate hymen (3 cases). Two false positives, not included in this group, resulting from appendicular abscesses and misinterpreted as ovarian, were submitted to surgery in a gynecologic unit. Group II: 19 patients treated with medical therapy for the following conditions: torsion or hemorrhage from hyperstimulated ovary (10 cases), pyosalpinx or tubo-ovarian abscess (9 cases). Group III: 25 patients in whom neither US nor clinical examination revealed positive gynecologic findings. Both US and clinical follow-up were negative in these patients. The study was aimed at evaluating the role of US in identifying both lesion and peritoneal involvement, and in the diagnosis of nature. US proved a valuable tool in the first two diagnostic steps, allowing to confirm/dismiss active pathologic conditions, to indicate the medical/surgical treatment (immediate or delayed), to detect associated pathologies to study with further examinations. As for lesion nature, US alone proved poorly useful if not correlated with an accurate clinical history.

[Inflammatory aneurysms of the abdominal aorta: US and CT characteristics]. / Gli aneurismi infiammatori dell'aorta addominale. Caratteristiche US e TC.

The authors report their experience with US and CT in 31 cases of inflammatory aneurysms out of a study population of 200 patients with abdominal aortic aneurysms. The work started with a case that had not been diagnosed at US, either due to the operator's poor knowledge of this pathologic condition or because of improper examination technique. The authors stress the importance of a high-frequency probe and proper gain settings which are often necessary for a good visualization of the anterior aortic wall. The correct diagnosis of the inflammatory nature of the aneurysm has been assessed by US ever since, in all cases except for very obese and meteoric patients. In our series, US diagnostic accuracy was 78%, versus 33% reported in literature. US was not accurate in evaluating adjacent structures involvement within fibrous tissues (ureteral narrowing, caval narrowing)--which CT did. Neither US nor CT exhibited reliable diagnostic accuracy in demonstrating enteric involvement within fibrous tissues.

[Impact of high resolution computerized tomography on the clinical assessment of pulmonary interstitial diseases]. / Impatto della tomografia computerizzata ad alta risoluzione sull'inquadramento clinico delle interstiziopatie polmonari.

Our purpose is to define the morphological patterns of interstitial lung disease on CT and to evaluate the diagnostic impact of high-resolution technique (HRCT). Sixty-six consecutive patients with proven interstitial lung disease were considered in our study. The basic morphological patterns include: a) large reticular pattern (10-25 mm); b) small reticular pattern (2-3 mm); c) intermediate reticular pattern (5-10 mm) with cystic dilatation of distal airspaces; d) nodular pattern; e) high-density parenchymal areas. Topography of the involved areas (peripheral, middle and axial compartments), and lesion distribution with reference to the secondary pulmonary lobule (centrilobular, perilobular, panlobular, bronchovasal) are additional diagnostic criteria. The identification and correlation of these three parameters proved very useful in limiting the range of diagnostic possibilities to interstitial disease, obviously considering clinical data. In our series a correct CT diagnosis was obtained in 57 of 66 cases (86.36%). In 24 of them (36.34%) diagnosis corrected a previous erroneous or generic clinical suspicion. Our data suggest that HRCT is indicated in interstitial lund disease when neither clinical nor radiographic findings allow a specific diagnosis to be made.

[Computerized tomography in post-operative recurrence of bronchial carcinoma]. / La tomografia computerizzata nelle recidive post-chirurgiche di carcinoma bronchiale.

The authors describe the different types of postoperative carcinoma recurrences, as seen on CT examinations of the chest, in 38 patients who underwent different surgical procedures for bronchogenic carcinoma (12 pneumonectomies, 22 lobectomies, 2 segmentectomies, and 2 atypical resections). The recurrences were classified as follows: 1) recurrence in the bronchial stump; 2) lymph node enlargement; 3) recurrence in the thoracic wall; 4) recurrence in the residual lobe; 5) pleural effusion; 6) nodule in the contralateral lung. The CT findings, correlated with those from plain chest radiographs and clinical symptoms, indicate a higher incidence of recurrences in the hilar region, either in the bronchial stump or as node enlargement. In the discussion, the problems faced after total and subtotal resection are separately analyzed. While after pneumonectomy plain chest radiographs fail to demonstrate the recurrence in most cases, so that CT is nearly always mandatory, after subtotal resection the diagnostic accuracy of conventional radiology appears higher since the residual parenchyma offers good natural contrast. Nevertheless, after subtotal resection, greater difficulties arise at a deeper radiological analysis due to lobar reassessment, the features of which are to be known.

[Use of echography in pathology of the maxillary sinuses]. / L'impiego dell'ecografia nella patologia dei seni mascellari.

Sonography has recently gained attention as a non-invasive technique improving the diagnostic accuracy of conventional radiology as regards the pathologic conditions of the maxillary sinus. Eighty-two patients with various pathologies of the maxillary sinus--i.e. acute/chronic sinusitis, mucocele, mucopyocele, polyp, and carcinoma--were submitted to US after preliminary conventional radiographs and before CT and surgical treatment (both performed in selected cases only). US proved useful in detecting liquid exudate, mucosal hypertrophy, and lesions of the anterior wall, while it was not as accurate in detecting lesions of the posterior wall (unless fluid was present) and in establishing the nature of a solid lesion. The last two conditions are those where CT is mainly indicated.