Explore the vast range of titles available.

Solitary pulmonary nodule (SPN, intraparenchymal lung mass <3 cm) is often a diagnostic challenge. This study was performed to evaluate the diagnostic accuracy of( 18)F-fluorodeoxyglucose positron emission tomography (FDG PET) in radiologically indeterminate SPN < or =10 mm on spiral CT. Between August 1997 and March 2001, we identified all patients with radiologically indeterminate SPNs < or =10 mm who were referred for FDG PET imaging at the VU University Medical Centre. All PET scans were retrospectively reviewed by an experienced nuclear medicine physician. PET was considered positive in cases with at least moderately enhanced focal uptake, and otherwise as negative. Lesions were considered benign on the basis of histology, no growth during 1.5 years or disappearance within at least 6 months. Thirty-five patients with 36 SPNs < or =10 mm in diameter at clinical presentation were identified (one patient had two metachronous lesions). In 13 of 14 malignant nodules and in two of 22 benign nodules, diagnosis was confirmed by histology. Prevalence of malignancy was 39%. PET imaging correctly identified 30 of 36 small lesions. One lesion proved to be false negative on PET (CT: 10 mm), and in five lesions, PET scans proved to be false positive. Specificity was 77% (17/22; 95% CI: 0.55-0.92), sensitivity 93% (13/14; 95% CI: 0.66-1.0), positive predictive value 72% (13/18; 95% CI: 0.46-0.90) and negative predictive value 94% (17/18; 95% CI: 0.73-1.0). This retrospective study suggests that FDG PET imaging could be a useful tool in differentiating benign from malignant SPNs < or =10 mm in diameter at clinical presentation. Such results may help in the design of larger prospective trials with structured clinical work-up.

The ability of conventional CT scans and fiberoptic bronchoscopy to localize and properly stage radiographically occult lung cancer (ROLC) in the major airways is limited. High-resolution CT (HRCT) scanning and autofluorescence bronchoscopy (AFB) may improve the assessment of ROLC before the most appropriate therapy can be considered. We prospectively studied 23 patients with ROLC, who were referred for intraluminal bronchoscopic treatment (IBT) with curative intent. Additional staging with HRCT and AFB was performed prior to treatment. Twenty patients were men, 9 patients had first primary cancers, and 14 patients had second primary cancers or synchronous cancers. HRCT scanning showed that 19 patients (83%) had no visible tumor or enlarged lymph nodes. With AFB, only 6 of the 19 patients (32%) proved to have tumors ≤ 1 cm2 with visible distal margins. They were treated with IBT. In the remaining 13 patients, abnormal fluorescence indicated more extensive tumor infiltration than could be seen with conventional bronchoscopy alone. Six patients underwent radical surgery for stage T1–2N0 (n = 5) and stage T2N1 (n = 1) tumors. Specimens showed that tumors were indeed more invasive than initially expected. The remaining seven patients technically did not have operable conditions, so they were treated with external irradiation (n = 4) and IBT (n = 3). The range for the time of follow-up for all patients has been 4 to 58 months (median, 40 months). The follow-up data underscore the correlation between accurate tumor staging and survival. Our data showed that 70% of patients presenting with ROLC had a more advanced cancer than that initially diagnosed, which precludes IBT with curative intent. Additional staging with HRCT and AFB enabled better classification of true occult cancers. Our approach enabled the choice of the most appropriate therapy for each individual patient with ROLC.

High-end enterprise storage has traditionally consisted of monolithic systems with customized hardware, multiple redundant components and paths, and no single point of failure. Distributed storage systems realized through networked storage nodes offer several advantages over monolithic systems such as lower cost and increased scalability. In order to achieve reliability goals associated with enterprise-class storage systems, redundancy will have to be distributed across the collection of nodes to tolerate both node and drive failures. In this paper, we present alternatives for distributing this redundancy, and models to determine the reliability of such systems. We specify a reliability target and determine the configurations that meet this target. Further, we perform sensitivity analyses, where selected parameters are varied to observe their effect on reliability.

Idiopathic spontaneous pneumothorax (SP) is the result of leakage of air from the lung parenchyma through a ruptured visceral pleura into the pleural cavity. This rupture is thought to be caused by an increased pressure difference between parenchymal airspace and pleural cavity. We hypothesize that rather peripheral airway inflammation leads to obstruction with check valve phenomena and by that to airtrapping in the lung parenchyma, which precedes spontaneous pneumothorax. University hospital. Forty-one matched healthy volunteers (21 smokers and 20 nonsmokers), and 41 patients with SP (21 patients with and 20 patients without bullae) underwent spirometrically controlled high-resolution CT density measurements with automatic contour tracing at 10% and at 90% of vital capacity. Patients with SP showed lower mean lung density (MLD) values and higher percentages of Hounsfield units (HU) below − 900 HU (pixel index [PI]) compared to the healthy volunteers on expiratory scans. This enhanced airtrapping phenomenon is seen in both the SP lung (MLD, p = 002; PI, p = 0.01) and the contralateral lung (MLD, p = 0.009; PI, p = 0.05) compared to the control subjects. The difference with control subjects is independent of smoking behavior and bullae. Peripheral airway obstruction with airtrapping was found, and it is supposed to play an important role in the pathogenesis of spontaneous pneumothorax.

Purpose The aim of the study was to assess the interobserver variability in chest computed tomography (CT) and whole body 2-deoxy-2-[ 18 F]fluoro- d -glucose positron emission tomography (FDG-PET) screening for distant metastases in head and neck squamous cell carcinoma (HNSCC) patients. Procedure Chest CT and whole body FDG-PET of 69 HNSCC patients with high-risk factors who underwent screening for distant metastases were analyzed. All scans were independently read by two experienced radiologists or nuclear physicians who were blinded to the other examinations and follow-up results. Results A kappa of 0.516 was found for assessment of size on CT. Kappa values for origin and susceptibility of 0.406 and 0.512 for CT and 0.834 and 0.939 for PET were found, respectively. The overall conclusions had a kappa of 0.517–0.634 for CT and 0.820–1.000 for PET. Conclusions In screening for distant metastases in HNSCC patients with high-risk factors, chest CT readings had a reasonable to substantial agreement, while PET readings showed an almost perfect agreement. These findings suggest that for optimal assessment in clinical practice, PET most often can be scored by one observer, but CT should probably more often be scored by different observers in consensus or combined with PET.

Nonseminomatous germ cell tumor of the testis stage I will relapse in approximately 30% of patients in the first year after orchidectomy. We report a 19-year-old patient on active surveillance who presented with a retroperitoneal lymph node enlargement suggestive of metastatic disease more than 1 year after the initial diagnosis of embryonal carcinoma stage IB. Complete resection of the lymph node was performed and showed the presence of mature teratoma. Our patient had an unusual case of metastasis formation of benign histology of a previously removed highly malignant primary tumor confined to the testis.

To evaluate the extent to whichhigh-resolution CT (HRCT) can predict the clinical outcome ofbronchoscopic treatment with curative intent in patients withintraluminal typical bronchial carcinoid tumors. An observational study. Bronchoscopy unit and radiology department of a universityhospital. Eighteenpatients with intraluminal typical bronchial carcinoid tumors in theabsence of nodal and distant disease were treated with bronchoscopicelectrocautery or Nd-YAG laser as an alternative to surgical resection.Prior to treatment, HRCT was performed. In 10patients, HRCT showed no peribronchial tumor extension, and 9 of thesepatients were found to be tumor free after bronchoscopic treatment. Sofar during follow-up, none of these patients has had a recurrence ofthe tumor. The median duration of follow-up was 33 months (range, 13 to68 months). In five patients, HRCT showed signs of peribronchial tumorextension. In three of these patients, specimens taken from biopsiesperformed after bronchoscopic treatment showed residual tumors, andsalvage surgery was carried out. In three patients, HRCT was unable toassess peribronchial tumor extension: in two because of insufficientconnective tissue contrast between the hilar structures and in onepatient because of suboptimal scan technique. HRCT findings were complementary but notconclusive in patients with intraluminal typical bronchial carcinoidtumors treated with bronchoscopic therapy. However, in a category ofpatients in whom HRCT showed strictly intraluminal tumors, bronchoscopic resection as an alternative for surgical resection seemsjustified.

The added value of 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) scanning as a function of pretest risk assessment in indeterminate pulmonary nodules is still unclear. To obtain an external validation of the prediction model according to Swensen and colleagues, and to quantify the potential added value of FDG-PET scanning as a function of its operating characteristics in relation to this prediction model, in a population of patients with radiologically indeterminate pulmonary nodules. Between August 1997 and March 2001, all patients with an indeterminate solitary pulmonary nodule who had been referred for FDG-PET scanning were retrospectively identified from the database of the PET center at the VU University Medical Center. One hundred six patients were eligible for the study, and 61 patients (57%) proved to have malignant nodules. The goodness-of-fit statistic for the model (according to Swensen) indicated that the observed proportion of malignancies did not differ from the predicted proportion (p = 0.46). PET scan results, which were classified using the 4-point intensity scale reading, yielded an area under the evaluated receiver operating characteristic curve of 0.88 (95% confidence interval [CI], 0.77 to 0.91). The estimated difference of 0.095 (95% CI, −0.003 to 0.193) between the PET scan results classified using the 4-point intensity scale reading and the area under the curve (AUC) from the Swensen prediction was not significant (p = 0.058). The PET scan results, when added to the predicted probability calculated by the Swensen model, improves the AUC by 13.6% (95% CI, 6 to 21; p = 0.0003). The clinical prediction model of Swensen et al was proven to have external validity. However, especially in the lower range of its estimates, the model may underestimate the actual probability of malignancy. The combination of visually read FDG-PET scans and pretest factors appears to yield the best accuracy.

This chapter explains accountability frameworks within the UN system and examines in more detail the three components of such a framework within and across various UNDS organizations. It provides a globally accepted set of objectives and against which to measure progress and impact. In 2011, the UN Joint Inspection Unit (JIU) issued a report that summarized concisely the key components of any accountability framework within the context of the UN system. All UN organizations certainly had the key components of internal controls and some of the complaints and response mechanisms; but there was little evidence of any formal and meaningful political covenants with member states at that time. These seven elements are: internal audit; external audit and the UN Board of Auditors; audit and oversight committees; evaluation; the Joint Inspection Unit; risk management; and ethics and financial disclosure. Audit and oversight committees are relatively recent elements for the UN’s governance and accountability.