CT halo sign: the spectrum of pulmonary diseases.

The CT halo sign indicates ground glass attenuation surrounding a pulmonary nodule on CT. Although it was initially proposed as an early, specific finding of invasive pulmonary aspergillosis, it can be caused by many other pathological conditions such as infection, neoplastic and inflammatory diseases. The halo of ground glass attenuation pathologically represents pulmonary haemorrhage, tumour infiltration, or non-haemorrhagic inflammatory processes. Although non-specific, this sign is important because the clinical setting and associated radiological features may give a clue to the differential diagnosis. In this review, we demonstrate the spectrum of pulmonary diseases showing the "CT halo sign" on thin-section CT and discuss their radiological and clinical features.

Idiopathic multilocular thymic cyst: CT features with clinical and histopathologic correlation.

OBJECTIVE: We performed this study to describe the CT features of idiopathic multilocular thymic cysts with clinical and histopathologic correlation. CONCLUSION: Multilocular thymic cysts typically manifest on CT as unilocular or multilocular cystic thymic masses, often with soft-tissue attenuation components. CT cannot be used to distinguish neoplastic from nonneoplastic soft-tissue components.

The "High-Riding" superior pericardial recess: CT findings.

OBJECTIVE. We recently observed patients in whom the superior pericardial recess extended cephalad ("high-riding") into the right paratracheal region. In these patients, differentiation from mediastinal lymphadenopathy or mass was difficult. The purpose of this study was to assess the prevalence and CT features of the high-riding superior pericardial recess. CONCLUSION. Narrow-collimation CT with multiplanar reformations was useful for confidently diagnosing a high-riding superior pericardial recess and for distinguishing it from pathologic lesions.

Esophageal tubular duplication complicated with intraluminal hematoma: a case report.

Esophageal tubular duplication is a rare congenital anomaly. We experienced a patient with esophageal tubular duplication who presented with a swallowing difficulty which was aggravated after a gastrofiberscopic examination. Preoperative diagnosis was intramural hematoma of the esophagus due to trauma caused by endoscopy. Surgical specimen revealed that hematoma was located within a duplicated lumen of the esophagus. The radiologic and endoscopic findings are discussed in correlation with its pathology.

Pneumocystis carinii pneumonia associated with a rapid reduction of cortisol level in a patient with ectopic ACTH syndrome treated by octreotide and ketoconazole.

A case is herein reported of pneumocystis carinii pneumonia in a 60-year-old female patient with ectopic production of ACTH at a position 2 cm superior to her right clavicle, revealed in an octreotide scan. Her extremely high plasma ACTH and cortisol levels (460 pg/ml and 80 microg/dl, respectively) were markedly decreased with the combined treatment of octreotide (300 microg/d) and ketoconazole (600 mg/d). As her serum cortisol concentration decreased, pneumocystis carinii pneumonia occurred on the third day of treatment. A secondary E. coli infection was superimposed and the patient died of disseminated intravascular coagulation and adult respiratory distress syndrome. This case suggests that primary prophylaxis for pneumocystis carinii infection should be initiated before cortisol lowering therapy, especially when the plasma cortisol concentration is excessively high, and that early adjunctive glucocorticoid therapy can reduce the acute mortality in patients with endogenous Cushing's syndrome and Pneumocystis carinii pneumonia. This case study would also like to point out that plasma ACTH and cortisol levels were decreased effectively by the combination of octreotide and ketoconazole in this instance of ectopic ACTH syndrome.

Mucormycosis of the central airways: CT findings in three patients.

Computed tomographic (CT) findings are described in three diabetic patients with central airways mucormycosis. The CT findings of the tracheobronchial mucormycosis include enhancing areas of mural thickening (n = 3), luminal narrowing (n = 3), intramural air (n = 3), low-attenuation nonenhancing bronchial wall thickening (n = 2), and bronchonodal fistula formation (n = 1). These CT features in a diabetic patient should raise a high index of suspicion for tracheobronchial mucormycosis, particularly when typical radiographic features of pulmonary tuberculosis are absent.

Tracheopathia osteoplastica simulating asthmatic symptoms. Diagnosis by bronchoscopy and computerized tomography.

Tracheopathia osteoplastica (TO) is a relatively rare benign disease of the trachea and major bronchi, characterized by cartilaginous and bony submucosal nodules covered by intact mucosa, which may cause narrowing and rigidity of the upper airways. The diagnosis of TO is rarely considered because of a lack of awareness of this entity, rather than the reported rare occurrence. We intend to report herein a case initially misinterpreted as bronchial asthma but later disclosed through computerized tomography (CT) and bronchoscopic biopsies as TO.

A case of aneurysm of the vein of Galen.

Aneurysm of the vein of Galen is a very rare disease. The authors present a case of secondary aneurysm of the vein of Galen which was confirmed by characteristic clinical symptoms, brain CT and angiographic findings. The patient was a 14-year-old right handed girl with intermittent headache, nausea, vomiting, dysphasia and gait disturbance. Neurologic examination revealed dysarthria, nasal voice, blurring of both margins of optic discs, truncal ataxia and dysdiadochokinesia. Sensory function was normal but right hemiparesis was seen. Roentgenogram of the skull revealed diffuse thinning of the calvarium, widening of sella turcica and erosion of clinoid processes. Computed tomogram of the brain showed dilatation of all ventricles and round hyperdense mass behind the third ventricle in the midline. The lesion was enhanced markedly and homogeneously. Left and right internal carotid angiograms showed arteriovenousmal-formation with drainage to the aneurysm of the vein of Galen.

Transcatheter renal arterial embolization with the mixture of ethanol and iodized oil (Lipiodol).

We induced experimental renal arterial embolization with the radiopaque solution of ethanol and iodized oil (Lipiodol) in 35 rabbits to evaluate the capability of the mixture to induce renal ablation. Serial renal angiography and plain abdominal radiography were performed immediately, one week and two weeks after embolization. Neither pure Lipiodol nor a 50% ethanol solution caused renal embolization. However, infusion of 50% and 75% ethanol-Lipiodol solutions resulted in embolization equal to that caused by absolute ethanol. The 50% ethanol-Lipiodol solution was so radiopaque that we could easily observe the embolization process during fluoroscopy. Renal arterial embolization with the 50% ethanol-Lipiodol solution was successful in three patients with hypernephroma. Our results suggest that a 50% ethanol-Lipiodol solution is radiopaque and an effective agent for renal arterial embolization.