T1 signal hyperintensity in the sellar region: spectrum of findings.

T1 signal hyperintensity is a common finding at magnetic resonance imaging of the sellar region. However, this signal intensity pattern has different sources, and its significance depends on the clinical context. Normal variations in sellar T1 signal hyperintensity are related to vasopressin storage in the neurohypophysis, the presence of bone marrow in normal and variant anatomic structures, hyperactive hormone secretion in the anterior pituitary lobe (eg, in newborns and pregnant or lactating women), and flow artifacts and magnetic susceptibility effects. Pathologic variations in T1 signal hyperintensity may be related to clotting of blood (in hemorrhagic pituitary adenoma, pituitary apoplexy, Sheehan syndrome, or thrombosed aneurysm) or the presence of a high concentration of protein (Rathke cleft cyst, craniopharyngioma, or mucocele), fat (lipoma, dermoid cyst, lipomatous meningioma), calcification (craniopharyngioma, chondroma, chordoma), or a paramagnetic substance (manganese, melanin). After treatment, T1 signal hyperintensity may result from the presence of materials used for surgical packing (gelatin sponge, fat); from compression of the cavernous sinus and reduction of the venous flow, caused by overpacking of the operative bed; or from hormone hypersecretion by a remnant of normal tissue in the anterior lobe of the pituitary gland.

Foramen tympanicum, or foramen of Huschke: pathologic cases and anatomic CT study.

BACKGROUND AND PURPOSE: A persistent foramen tympanicum, or foramen of Huschke, is an anatomic variation of the tympanic portion of the temporal bone due to a defect in normal ossification in the first 5 years of life. The foramen is located at the anteroinferior aspect of the external auditory canal (EAC), posteromedial to the temporomandibular joint (TMJ). We sought to define its prevalence, location, and size on high-resolution spiral CT (HRCT). METHODS: We prospectively examined 102 consecutive HRCT studies of the temporal bone (204 ears). HRCT was performed by using 120 kV, 400 mAs, an ultra-high-resolution filter, 0.6-mm section thickness, 0.3-mm section increment, 728 x 728 matrix, and 160-mm field of view. We noted the size and location of the foramen tympanicum relative to the tympanic membrane and calculated its prevalence. Patients with focally decreased tympanic bone thickness of <1 mm at the anteroinferior EAC (between the 3- and 6-o'clock positions) were considered separately. RESULTS: We found a foramen tympanicum was found in six (4.6%) of 130 ears. Mean axial diameter was 4.2 mm, and mean sagittal diameter was 3.6 mm. Focally reduced bone thickness in the same location was found in 45 (35%) ears, with a female preponderance (P = .003). CONCLUSION: HRCT is sensitive for detection of the foramen tympanicum because of its thin sections, high spatial resolution, and multiplanar capabilities. Awareness of this anatomic entity may be useful in evaluating patients with transient otorrhea in whom no otologic cause (e.g., ear infection, TMJ disease) is identified.

A rare expression of neural crest disorders: an intrasphenoidal development of the anterior pituitary gland.

Congenital abnormalities of the pituitary gland are rare and may be associated with midline cranial, orbital, and facial anomalies and with hormonal insufficiency. Here we report a case of asymptomatic, abnormal migration of the adenohypophysis. The normally developed adenohypophysis was located in the sphenoid bone and developed on the intersphenoidal septum, extending from the superior pharyngeal wall to the floor of the sella turcica (craniopharyngeal canal). The abnormal migration of the pituitary gland was isolated without hormonal deficit, brain, or facial developmental anomalies.

Wegener granulomatosis involving the pterygopalatine fossa: an unusual case of trigeminal neuropathy.

We report on a case of Wegener granulomatosis in the pterygopalatine fossa that was associated with trigeminal neuropathy. MR and CT examinations were useful in depicting the extent of the lesion and suggesting a perineural spread. Diagnosis was confirmed with positive serum assay findings for the presence of cytoplasmic antineutrophil cytoplasm antibody.

Granular cell tumor of the palate: a case report.

Granular cell tumor (GCT) is an infrequent benign neoplasm, which Abrikosoff accurately described in 1926. GCT probably has a neural crest cell origin. We present the clinical and imaging findings in a 45-year-old woman with a GCT involving the palate. CT and MR imaging revealed perineural tumor spread along the greater and lesser palatine nerves. We emphasize the peculiarity of the palatine location and the perineural spread of GCTs.

Massive calcium pyrophosphate dihydrate crystal deposition disease: a cause of pain of the temporomandibular joint.

Calcium pyrophosphate dihydrate deposition (CPDD) disease is a disorder that occasionally affects the temporomandibular joint (TMJ) and temporal bone, causing pain (66.6% of cases), swelling (50%), trismus (36.8%), and hearing loss (22.2%). Diagnosis of CPDD is challenging because clinical symptoms and imaging features are not characteristic and may mimic a chondrosarcoma. When the diagnosis of CPDD of the TMJ is under consideration, conventional radiographs of the wrist or the knee may contribute to the final diagnosis. Imaging features of CPDD are discussed with a review of the literature.

[A palate tumor revealed by pain]. / Une tumeur du palais révélée par des douleurs.

A 41-year-old female presented in April 1996 with a tumor of the hard palate revealed by increasing left palate pain. Adenoid cystic carcinoma was suspected on clinical and imaging data. Two limited surgical procedures showed a tumor histologically made of small lobules of granular cells, PAS positive and expressing S100 protein, infiltrating some medullary spaces of the palatine bone, consistent with a granular-cell tumour. Pain recurred in the territory of the maxillary branch of the left trigeminal nerve (V2). Imaging showed a tumor of the origin of V2-extending through the foramen rotondum. Two radical interventions in September and in October 2000 showed an infiltrating tumor of the V2 and palatine mucosa, with the same histology. There was no immuno-staining for p53, and less than 5% of nuclei expressed Ki67. Malignant Abrikossof tumors are exceptional, morphologically difficult to differentiate from benign ones, only metastasis proving malignancy. Tumor size above 5 cm, recurrence and infiltrative character are considered pejorative. The value of p53 and Ki67 expression remains controversial. We discuss our observation according to these criteria.

Septic thrombosis of the transverse and sigmoid sinuses: imaging findings.

The purpose of this study was to evaluate the contribution of magnetic resonance imaging (MRI) to the diagnosis of septic thrombosis of transverse and sigmoid sinuses to analyze the different steps of the diagnosis and to identify the origin of the difficulties in diagnosis. This retrospective study included eight patients aged 53-81 years (mean age: 61.9 years) with proven or highly probable septic thrombosis of transverse and sigmoid sinuses. All patients underwent a pre- and post-contrast enhancement brain CT scans and MRI. MR venogram (n=4) and HRCT of the temporal bone were performed when diagnosis was under discussion. After admission, the delay in diagnosis of lateral sinus thrombosis ranged from 8 to 60 days, with an average of 27 days (SD: +/-12.8). The delay in diagnosis was mainly due to non focused CT scans (6/8) or MR images performed at the initial presentation and absence of systematic radiological reading of the related fatty spaces and of skull base in bone windows (3/8). Diagnosis of septic origin of the thrombosis is of great importance, as it completely modifies the therapeutic planning of the patients. However, it remains a difficult challenge due to its lack of suggestive neurological or otolaryngologic symptoms.