Hemangioma of the nasal vault: MR and CT features

Six patients with a history of epistaxis (five patients) or nasal obstruction (one patient) were found to have a capillary hemangioma of the nasal vault that involved one or more nasal turbinates. Four patients underwent computed tomographic (CT) examination; two of these also underwent magnetic resonance (MR) imaging. Four others underwent only MR imaging. At CT and MR, all of the lesions were well circumscribed and intensely enhancing, with contralateral deviation of the nasal septum. Remodeling of the surrounding bone was present in three patients. On T1-weighted MR images, the masses were intermediate in signal intensity. Varying degrees of T2 shortening were shown on T2-weighted MR images, with an appearance that suggested the presence of blood products surrounding an inner matrix of higher-signal-intensity tumor. Intense enhancement at CT and MR assisted differentiation of tumor from retained sinonasal secretions. In two patients, external carotid arteriography revealed small foci of pooling contrast material; in one of these patients, arteriovenous shunting was also present. Pathologic examination in all patients demonstrated capillary hemangiomas with varying degrees of fibrosis and hemosiderin deposition.     

The CT findings of acute thyroiditis and acute suppurative thyroiditis

Although acute thyroiditis often has a distinctive clinical presentation, this relatively uncommon entity can occasionally be confused with other inflammatory processes. In general, the earlier the diagnosis of acute thyroiditis is established, the lower is the frequency and severity of its attendant complications. Computed tomography (CT) is an extremely useful modality in establishing the diagnosis early because it can evaluate iodine content of the thyroid gland and provides more accurate mapping than ultrasound and nuclear medicine techniques. Three patients with acute thyroiditis--two with suppuration--are presented and the CT findings and clinical aspects of this disease are reviewed.     

Inflammatory pseudotumor of the maxillary sinus in a 15-year-old boy.

Inflammatory pseudotumor is a benign neoplasm composed of fibroblasts, histiocytes, and inflammatory cells. Its occurrence in the paranasal sinuses is rare. We report a case of a 15-year-old boy with a maxillary sinus inflammatory pseudotumor that simulated an aggressive neoplasm on CT scan.     

Central nodal necrosis and extracapsular neoplastic spread in cervical lymph nodes: MR imaging versus CT.

Computed tomographic (CT) scans and magnetic resonance (MR) images obtained in 24 patients with cervical lymphadenopathy were retrospectively and blindly evaluated by two readers for the presence of central nodal necrosis (CNN) and extracapsular nodal spread (ENS). The CT studies were all enhanced, and the MR images were obtained with short repetition time (TR)/echo time (TE), long TR/double echo, and enhanced short TR/TE fat-suppressed sequences. Each MR imaging sequence was interpreted separately and then collectively. Sixty lymph nodes were identified with CT. Sensitivity for CNN was 16%-67% with the unenhanced MR pulse sequences, 50% with enhanced sequences, and 83%-100% with CT. The most accurate reading of MR images for CNN was with the unenhanced T1-weighted and T2-weighted images (86%-87%); the accuracy of CT was 91%-96%. The accuracy of MR imaging for detecting ENS was maximal with T1-weighted images (78%-90%). Gadolinium-enhanced, fat-suppressed images did not improve accuracy in evaluating CNN or ENS. CT is currently more accurate than unenhanced or enhanced MR imaging in detecting CNN or ENS.     

Adenosquamous carcinoma of the facial bones,skull base,and calvaria: CT and MR manifestations.

A 62-year-old woman had proptosis of the right eye, decreased visual acuity of the left eye, and no other focal neurologic deficits. She had a grand mal seizure 1 month before admission. The CT and MR studies showed extensive bone destruction of the margins of the right orbit, the floor of the middle cranial fossa, the right cavernous sinus, and much of the calvaria. There was considerable dural disease and tumor in the right orbit, paranasal sinuses, and scalp, as well as mucoceles of the left ethmoidal sinus with desiccated secretions. The diagnosis was adenosquamous carcinoma, an aggressive tumor related to both squamous cell carcinoma and adenocarcinoma.     

Differentiation of subtypes B and E of human immunodeficiency virus type 1 by polymerase chain reaction using novel env gene primers

Novel sets of env gene PCR primers for distinguishing human immunodeficiency virus type 1 (HIV-1) subtypes B and E were designed. These primers anneal to different regions of the env gene and amplify DNA fragments of distinct sizes in a subtype-specific manner. Blood samples from 11 HIV-1 carriers in Thailand and 46 carriers in Japan were examined by PCR. The new env primers detected HIV-1 proviral DNA in 100% (11/11) and 88% (37/42) of the subtype B and E infection cases, respectively. The env primers also detected proviral DNA in saliva and breast milk samples in seven of 11 cases and two of three cases, respectively. The PCR subtyping results matched completely with those obtained by nucleotide sequencing of the env V3 region. The results suggest that the PCR using the env primers designed in this study may be an accurate and cost-effective method for differentiating subtypes B and E of HIV-1 in a large number of clinical samples. However, subtype E specific primer cross-react with subtype A, C, G, the new primer in this study is useful for regions in South East Asia where subtype E is predominant.