Detection of noncalcified pulmonary nodules on low-dose MDCT: comparison of the sensitivity of two CAD systems by using a double reference standard.

PURPOSE: This study compared the sensitivity of two commercial computer-aided detection (CAD) systems in identifying noncalcified pulmonary nodules on low-dose multidetector computed tomography (MDCT) scans by using a double reference standard. MATERIALS AND METHODS: Three chest low-dose MDCT scans of patients who had undergone lung cancer screening were retrospectively analysed using two distinct commercial CAD systems: LungCAD VC10A, Siemens Medical Solutions (CAD1) and LungVCAR, GE Healthcare (CAD2). The exact location of each finding suggested by each system was recorded by an independent reader according to spatial coordinates (x, y, z). Two panels of experienced thoracic radiologists from two different institutions independently established two reference standards (RS1, RS2) by identifying the true positive findings with spatial coordinates without using CAD. Sensitivity of the two CAD systems, defined by lesionlevel analysis, was tested and sensitivities compared. RESULTS: RS1 identified 34 noncalcified pulmonary nodules, whereas RS2 identified 54. The total number of findings detected by the two CAD systems was 684. CAD1 correctly identified 13/34 nodules (sensitivity 38%) for RS1 and 17/54 (sensitivity 30%) for RS2, whereas CAD2 correctly identified 11/34 nodules (sensitivity 35%) for RS1 and 13/54 (sensitivity 23%) for RS2. Comparison between the two CAD systems did not show a statistically significant difference in terms of sensitivity (p<0.05) for both RS1 (p=0.42) and RS2 (p=0.33). CONCLUSIONS: The two commercial CAD systems had similar sensitivity in detecting noncalcified pulmonary nodules on low-dose MDCT of the chest.

Central nervous system tuberculosis in non-HIV-positive children: a single-center, 6 year experience.

PURPOSE: The aim of this paper is to describe the imaging features of central nervous system (CNS) tuberculosis on computed tomography (CT) and magnetic resonance imaging (MRI) studies in non-HIV-positive children. MATERIALS AND METHODS: A retrospective descriptive evaluation was conducted on imaging studies obtained from ten children admitted to our hospital over a 6-year period who fulfilled criteria for a diagnosis of CNS tuberculosis. Data were collected with regard to patients' clinical, laboratory and demographic characteristics, as well as results of radiological investigation. RESULTS: We studied ten children, of whom five were boys and five were girls and whose mean age was 4 (range 7 months to 16) years. Neuroradiological findings on the first imaging study were basal meningeal enhancement (100%), hydrocephalus (70%), infarcts (90%), tuberculomas (40%) and cranial nerve involvement (20%). Follow-up studies revealed basal meningeal enhancement, hydrocephalus, and infarcts in all patients, tuberculomas in 70% and cranial nerve involvement in 50%. Only one patient showed a pattern of miliary tuberculosis. CONCLUSIONS: CNS tuberculosis is still an important cause of childhood morbidity and mortality even in nonimmunosuppressed children. Because prompt diagnosis results in earlier treatment, it is crucial to be aware of tuberculous meningitis and its complications at imaging, especially because of the impact on patients' prognosis.

Parapharyngeal neuroglial heterotopia in Pierre Robin sequence: MR imaging findings.

Heterotopic neuroglial tissue is a rare lesion, occurring more frequently in the nasal cavities. Other rare locations are the orbit, the scalp, the palate, the pharynx, the parapharyngeal space and the lungs. They are usually detected occasionally because they are often asymptomatic, but sometimes they might present with dyspnoea, feeding difficulty, snorting and nasal flaring. Respiratory symptoms occur when heterotopic neuroglial tissue is located in the parapharyngeal space. We report a case of an infant affected by Pierre Robin sequence (PRS) who was admitted to our Institution for a worsening respiratory distress that was not explainable only by PRS.

Cryptogenic haemoptysis in smokers: angiography and results of embolisation in 35 patients.

The aim of the present study was to describe angiographic findings and embolisation results in smokers with haemoptysis. We retrospectively reviewed the clinical data and angiographic findings from 35 patients with smoking-related bronchopulmonary disease and no associated comorbidity, who were referred for embolisation for mild (n = 6), moderate (n = 14) and severe (n = 15) haemoptysis. Spirometric classification subdivided our population into: 16 patients with chronic bronchitis but no airflow limitation; and 19 patients with chronic obstructive pulmonary disease (COPD) (stage I: n = 12; stage II: n = 5; stage III: n = 2). Bronchoscopy depicted focal submucosal vascular abnormalities in three patients and only endobronchial inflammation in 32 (91%) patients. Bronchial artery angiography revealed moderate (n = 18) or severe (n = 10) hypervascularisation in 28 (80%) patients, and normal vascularisation in seven (20%). No statistically significant difference was observed between the angiographic findings and the severity of COPD, tobacco consumption or the amount of bleeding. Cessation of bleeding was obtained by embolisation in 29 out of the 34 technically successful procedures (85%), requiring surgery in three out of five patients with recurrence. Follow-up (mean duration 7 yrs) demonstrated no recurrence of bleeding in 32 (94%) out of 34 patients and excluded late endobronchial malignancy. Smokers with various stages of COPD severity may suffer from haemoptysis that is efficiently treatable by endovascular treatment.