Magnetic resonance (MR) imaging in the open- and closed-mouth positions is the method of choice for visualizing the temporomandibular joint (TMJ). To analyze the TMJ in response to various degrees of mouth opening, the authors constructed a hydraulic incremental jaw opener. This apparatus enables obtaining of reproducible and stable positions of TMJ articulation. With modified gradient pulse sequences, the technique yields good spatial resolution of joint anatomy, including that of the articular disk. The application of a cine program allows cinematographic display of TMJ motion, which in conjunction with static open- and closed-mouth views can be useful in the diagnosis of TMJ dysfunction. The authors used the incremental jaw opener to examine the disk-condyle complex at each open-mouth position, with particular attention to extreme open-mouth positions.

Equipment Design↗

PubMedDate not supplied

Three-dimensional MR reconstruction images of skull base tumors.

Forty-eight patients with skull base tumors were evaluated prospectively with T1-weighted spin-echo two-dimensional (2D) magnetic resonance (MR) sequences, a three-dimensional (3D) MR TurboFLASH (fast low-angle shot) sequence, and a 3D reconstruction window technique. All patients underwent surgery with histopathologic correlation, and the three MR imaging techniques were compared to assess representation of tumor margins and the topographic relationship of tumor to surrounding tissue and adjacent vasculature. The best results were obtained with standard 2D spin-echo sequences after administration of the paramagnetic contrast agent gadopentetate dimeglumine. The 2D MR sequences gave the highest contrast-to-noise ratios, with decreasing values for 3D sequences and 3D reconstructions, respectively. Nevertheless, 3D MR imaging, by virtue of its good representation of adjacent structures, aided surgeons in planning surgical intervention. This study presents the technical features of 3D imaging of the skull base, the choices involved in its implementation, and its potential clinical applications.

Brain Neoplasms↗

PubMedDate not supplied

MRI in pre- and postoperative assessment of tracheal stenosis due to pulmonary artery sling.

OBJECTIVE: To evaluate the potential of MRI in the assessment of tracheal stenosis due to tracheal or vascular malformations, 45 children with severe respiratory distress were examined prospectively during a period of 1 year. Five of these children had tracheal stenosis due to a sling left pulmonary artery (SLPA). MATERIALS AND METHODS: Magnetic resonance examinations of the anesthetized children were performed with a 1.5 T Siemens MR imager using electrocardiographically gated T1-weighted SE sequences in transverse and sagittal slice orientations. Slice thickness was 3 mm and each sequence was repeated after shifting the slice position by 1 mm. Monitoring during the examinations included ECG, oscillatory blood pressure, respiratory rate, and oxygen concentration. Magnetic resonance findings were compared with esophagography, selective pulmonary angiography, bronchoscopy, Doppler sonography, and surgery. All examinations were repeated after surgical therapy to assess the improvement in tracheal stenoses and the patency of the ligated and reimplanted left pulmonary arteries. RESULTS: Magnetic resonance imaging clearly revealed the course of the SLPA and its topographic relationship to the trachea as well as the coexistence of cardiovascular and tracheobronchial or esophageal malformations. The degree and length of tracheal stenoses, which were measured in the pre- and postoperative axial slices and graphically displayed, as well as the angles of the right and left main stem bronchi, could be accurately determined. CONCLUSION: Magnetic resonance imaging in combination with bronchoscopy yielded the necessary and sufficient information for diagnosis and aided the surgeon in planning operative strategy and in postoperative follow-up.

Angiography↗

PubMedDate not supplied

The application of the sepharose bead immunofluorescence test for the detection of allergen-specific IgE and IgG antibodies in pollinosis.

A new application of the Sepharose bead immunofluorescence test for detection of allergen-specific IgE and IgG antibodies is described. Allergen extracts of four different grass pollens were coupled to CNBr-activated Sepharose 4B. Twenty normal and allergic sera were incubated with the allergen-coupled beads, washed and incubated with fluorescence-conjugated anti-gamma E and G globulins. After washing and staining with 0.5% trypan blue, the percentage of fluorescent beads was detected by fluorescence microscopy. In the IgG/anti IgG system, the smallest amount of IgG demonstrated was 20ng/ml; in the IgE/anti-IgE system it was 40ng/ml. Independent examination of tests gave a mean difference between observations of 4.1%. Reproducibility was also very good (var. coeff = 18%). The number of beads stained with IgE correlated well with intensity of skin reactions to the same extracts (r = 0.64; p = 5 x 10-7), the percentage of IgG stained beads being independent of skin reactivity. The Sepharose-IgE test allowed clear distinction between allergic and normal sera (p = 4 x 10-7), while the Sepharose IgG test did not distinguish between them at the time of diagnosis. However, the number of beads stained with IgG significantly increased in patients undergoing immunotherapy (p = 3.8 x 10-3). The Sepharose bead immunofluorescence test requires a very small amount of materials, is highly sensitive and easy to handle. It may be valuable in the "in vitro" diagnosis of grass pollen allergy and useful in evaluating immunotherapy.

Allergens↗

PubMedDate not supplied

CT of the "Tegernsee Giant": juvenile gigantism and polyostotic fibrous dysplasia.

We report the radiological findings in the unusual case of the Bavarian "Tegernsee Giant." With conventional radiography, CT, and histologic examination, we succeeded in diagnosing two disorders: The Tegernsee Giant suffered from (a) juvenile gigantism caused by a growth hormone-secreting tumor of the pituitary gland and (b) a polyostotic form of fibrous dysplasia of the skull and multiple bones particularly on the left side of the body.

Adult↗

PubMedDate not supplied

Third cranial nerve palsy caused by gummatous neurosyphilis: MR findings.

The clinical and MR findings in an unusual case of gummatous neurosyphilis are reported. A 44-year-old woman suffering from diplopia and right-sided headaches was admitted. Physical examination and routine laboratory parameters were normal except for a third-nerve palsy. MR images revealed a contrast-enhancing lesion of the upper brain stem and third cranial nerve. Differential diagnosis included neuroma of the third cranial nerve, as well as neurosarcoidosis and other inflammatory processes. Serologic tests and lumbar puncture revealed the presence of active syphilis. After intravenous treatment with penicillin G, follow-up MR examinations showed diminishing size of the lesion with its complete resolution within 3 months.

Adult↗