A 60-year-old lady with previous hypertension was studied with PET in the acute (early recovery) phase of an otherwise typical episode of transient global amnesia (TGA). Follow-up over > 1 year was ...uneventful, and delayed CT scans and MRI showed no brain damage. No medical cause was disclosed despite extensive work-up. The PET study revealed a matched reduction in cerebral blood flow and oxygen consumption over the entire lateral frontal cortex on the right side, with an associated, less significant reduction in ipsilateral thalamic and lentiform nucleus metabolism, but sparing the hippocampal area. These changes, which had resolved at a repeat PET study 3 months later, suggest right prefrontal metabolic depression, possibly secondary to thalamic dysfunction, as the underlying mechanism for TGA in this case, consistent with the emerging involvement of the prefrontal cortex in strategies or control of memory traces retrieval. Thus, in analogy with permanent amnesia, TGA may be a core syndrome with several possible foci of dysfunction along the neuronal networks that subserve explicit memory. In the future, combined PET neuropsychological assessment in the acute stage of TGA may prove useful in defining distinct neuropsychological-topographical subtypes of this intriguing clinical entity.
The tokamak Tore Supra was initially designed to operate long pulses, though the control and data acquisition systems nevertheless had to be upgraded to effectively perform these long-duration ...pulses. Continuous data acquisition was required for controlling the thermal phenomena, and huge amounts of data had to be handled, especially with the development of video imaging for the safety of the actively cooled vessel. A distributed architecture had to be developed so that real-time feedback could be implemented to ensure safe operation and to optimize the long-duration plasma performance. This paper briefly describes the initial control and data acquisition system and then reviews the developments and enhancements that were made to perform long pulses in Tore Supra.
The tokamak Tore Supra was initially designed to operate long pulses, though the control and data acquisition systems nevertheless had to be upgraded to effectively perform these long-duration ...pulses. Continuous data acquisition was required for controlling the thermal phenomena, and huge amounts of data had to be handled, especially with the development of video imaging for the safety of the actively cooled vessel. A distributed architecture had to be developed so that real-time feedback could be implemented to ensure safe operation and to optimize the long-duration plasma performance. This paper briefly describes the initial control and data acquisition system and then reviews the developments and enhancements that were made to perform long pulses in Tore Supra.
To review the computed tomography (CT) imaging features of pulmonary nocardiosis (PN) at the time of initial presentation.
All patients from 1991 to 2008 with PN were identified (n=105). Patients ...without CT scan available at initial presentation were excluded (n=52). For the remaining 53 patients, standardized radiographic features were recorded. The patients were grouped by predisposing condition. Analysis includes descriptive summary statistics as well as associations among radiographic findings, associated findings, and host characteristics. Parametric and nonparametric statistical methods were used.
Median age of the patients was 52 years (range, 6 to 82 y). Some form of immunosuppression was present in 83% of the cases. Preexisting structural abnormalities of the lung were uncommon (bronchiectasis, 7; chronic obstructive pulmonary disease, 3). Twenty (38%) patients had interstitial opacities. Airspace disease was seen in 34 (64%) cases. Thirty (57%) cases revealed discrete nodules, 25 patients had 1 to 6 nodules (mean, 2), and 5 patients had fewer than 6 nodules, with the mean size of the largest nodule being 1.67 cm. Masses were seen in 11 patients (21%), 9 of whom had concomitant nodules. Cavitary lesions, including nodules, masses, or airspace disease, occurred in 40% of the cohort. Mediastinal lymphadenopathy was present in 8 (15%) patients. Fifteen patients (28%) had pleural effusions; the effusions were unilateral in 10 patients. Analysis of radiographic associations with patient groups found discrete nodules to be more often associated with immunosuppression compared with the nonimmunosuppressed group (66% vs. 11%; P=0.0067).
The CT presentation of PN is heterogeneous. Airspace disease appeared most frequently (in 64% of the cases), and nodules were present in 57% of the cases. Nocardiosis should be considered in the differential diagnosis of immunosuppressed patients with new nodules or masses.
To evaluate the performance of radiology residents in the interpretation of on-call, emergency "triple-rule-out" (TRO) computed tomographic (CT) studies in patients with acute chest pain.
The study ...was institutional review board-approved and Health Insurance Portability and Accountability Act compliant. Data from 617 on-call TRO studies were analyzed. Dedicated software enables subspecialty attendings to grade discrepancies in interpretation between preliminary trainee reports and their final interpretation as "unlikely to be significant" (minor discrepancies) or "likely to be significant" for patient management (major discrepancies). The frequency of minor, major and all discrepancies in resident's TRO interpretations was compared to 609 emergent non-electrocardiography (ECG)-synchronized chest CT studies using Pearson χ(2) test.
Minor discrepancies occurred more often in the TRO group (9.1% vs. 3.9%, P < .001), but there was no difference in the frequency of major discrepancies (2.1% vs. 2.8%, P = .55). Minor discrepancies in the TRO group most commonly resulted from missed extrathoracic findings with missed liver lesions being the most frequent. Major discrepancies mostly encompassed cardiac and extracardiac vascular findings but did not result in unnecessary interventions, significant immediate changes in management, or adverse patient outcomes.
On-call resident interpretation of TRO CT studies in patients with acute chest pain is congruent with final subspecialty attending interpretation in the overwhelming majority of cases. The rate of discrepancies likely to affect patient management in this domain is not different from emergent non-ECG-synchronized chest CT.
Four cases of Lemierre syndrome are reported in which metastatic abscesses resulted from septic thrombosis of the internal jugular vein secondary to bacterial pharyngitis. While chest radiographic ...findings were nonspecific, results of computed tomography (CT) of the thorax in each case were highly suggestive of septic pulmonary emboli. Internal jugular venous thrombosis was demonstrated at ultrasonography and contrast material-enhanced CT.
Computed tomography (CT) is the most common method of staging lung cancer. We have previously shown endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) to be highly accurate in staging ...patients with nonsmall cell lung cancer (NSCLC) who have enlarged mediastinal lymph nodes on CT scan. In this study we report the accuracy and yield of EUS-FNA in staging patients without enlarged mediastinal lymph nodes by CT.
Patients with NSCLC and CT scan showing no enlarged mediastinal lymph nodes (> 1 cm for all nodes except > 1.2 cm for subcarinal) in the mediastinum underwent EUS. Fine needle aspiration was performed on at least one lymph node, if present, in the upper mediastinum, aortopulmonary window, subcarinal, and periesophagus regions. Each specimen was evaluated with on-site cytopathology and confirmed with complete cytopathologic examination.
Sixty-nine patients without enlarged mediastinal lymph nodes were evaluated. Endoscopic ultrasound detected malignant mediastinal lymph nodes in 14 of 69 patients as well as other advanced (American Joint Committee on Cancer AJCC stage III/IV) in 3 others (1 left adrenal, and 2 with mediastinal invasion of tumor) for a total of 17 of 69 (25%, 95% confidence interval: 16% to 34%) patients. Eleven additional patients were found to have advanced disease by bronchoscopy (2), mediastinoscopy (2), and thoracotomy with mediastinal lymph node dissection (7). The sensitivity of EUS for advanced mediastinal disease was 61% (49% to 75%), and the specificity was 98% (95% to 100%).
Endoscopic ultrasound guided fine needle aspiration can detect advanced mediastinal disease and avoid unnecessary surgical exploration in almost one of four patients who have no evidence of mediastinal disease on CT scan. In addition to previously reported results in patients with enlarged lymph nodes on CT, these data suggest that all potentially operable patients with nonmetastatic NSCLC may benefit from EUS staging.
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