Nasoalveolar cyst is a rare nonodontogenic cyst arising in the nasoalar region of the face. In this case, a 39-year-old female had a nontender, fluctuant, soft, round, and bluish lesion in the right anterior gingiva of the right maxilla. Panoramic and magnetic resonance imaging examinatioins were performed. No abnormality was evident on the radiograph. The lesion was hypointense signal intensit...

MRI protocol Optimal characterization of musculoskeletal tumors at MRI involves certain basic requirements. High-resolution, small-field-of-view axial T1-weighted spin-echo and fatsuppressed T2-weighted fast (turbo) spin-echo images should be obtained through the entire tumor. T1-weighted images are critical in showing the presence of fat or hemorrhage within a mass; distinguishing normal marro...

Primary AT/RT is a rare highly malignant tumor of the CNS, usually occurring in children younger than 5 years of age. The objective of this study was to characterize the CT and MR imaging findings in a series of 5 adult patients with pathologically proved AT/RT. All 5 AT/RTs were supratentorial. In 2 patients who underwent nonenhanced CT, the tumors appeared isoattenuated, and 1 of the 2 tumors...

MR images of 14 patients with pyogenic and three patients with tuberculous infectious spondylitis were studied to develop criteria for diagnosis. T1-weighted scans, 800/20 (TR/TE), were obtained in 17 patients and T2-weighted scans, greater than 2000/30,80, were obtained in 14. In seven patients, T2*-weighted scans (gradient-recalled acquisition into steady state, 25/15/5-7 degrees [TR/TE/flip ...

Images acquired using the TrueFISP technique (true fast imaging with steady-state precession) are generally believed to exhibit T(2)/T(1)-weighting. In this study, it is demonstrated that with the widely used half-flip-angle preparation scheme, approaching the steady state requires a time length comparable to the scan time such that the transient-state response may dominate the TrueFISP image c...

OBJECTIVE: Spiral Projection Imaging (SPI) is a versatile, fast 3D data acquisition. Data are sampled on 2D spiral planes that are rotated to fill a sphere in k-space (figure 1). The spiral basis of SPI provides flow insensitivity. Furthermore, it has been shown that SPI allows for six degrees of motion correction similar to that used in PROPELLER. SPI requires far fewer excitations than a line...

To compare conventional and fat suppression MR imaging in their ability to detect head and neck lesions, we prospectively studied 17 patients with head and neck tumors and one normal volunteer. Five patients had benign tumors (one mixed cell tumor, one hemangioma, one lipoma, and two plexiform neurofibromas), 10 had malignant tumors (six squamous cell carcinomas, two minor salivary gland carcin...

BACKGROUND The proper diagnosis and management of patients after surgery for pituitary tumors are of great importance in clinical practice. The purpose of this study was to investigate the magnetic resonance features of the postoperative sella with fast spin echo T2-weighted imaging and to evaluate the benefits of this sequence compared to the classically performed contrast-enhanced T1-weighted...

Neurilemmoma of the oculomotor nerve is rare and infrequently presents as an orbital mass. We report a neurilemmoma arising from the cavernous sinus with its major part extending into the orbit. The Antoni A part of the neurilemmoma showed intermediate signal intensity in both T1- and T2-weighted MR images and exhibited postcontrast enhancement. The Antoni B part revealed hypointensity on T1-we...