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J T Wald

Publications and source records attributed to J T Wald.

6 recordsLinked to original sources
PubMed2006

Percutaneous sacroplasty using CT fluoroscopy.

Sacral insufficiency fractures frequently cause significant pain and limit activities of daily living in patients with osteoporosis. Percutaneous vertebroplasty is a common procedure to alleviate the pain associated with thoracic and lumbar vertebral compression fractures. The sacral percutaneous vertebroplasty procedure (sacroplasty) has recently been introduced as an alternative to medical management of osteoporotic sacral insufficiency fractures. We describe our CT fluoroscopy technique in performing percutaneous sacroplasty.

Administration, Cutaneous↗
PubMed2006

A modified vertebroplasty approach for spine biopsies.

There are various techniques available for percutaneous biopsy of suspected diskitis/osteomyelitis. Our technique has evolved as our experience with percutaneous vertebroplasty has grown. By using a transpedicular approach, we angle a bone biopsy needle in an exaggerated caudocranial trajectory to allow eventual access across the disk space above. This approach permits sampling of the disk space, as well as both adjacent vertebral endplates. We describe our percutaneous modified vertebroplasty approach for biopsy of suspected diskitis/osteomyelitis.

Aged↗
PubMed2001

Combined oligodendroglioma/pleomorphic xanthoastrocytoma: a probable collision tumor: case report.

OBJECTIVE AND IMPORTANCE: We report the first case of combined oligodendroglioma and pleomorphic xanthoastrocytoma. CLINICAL PRESENTATION: A female college student and competitive cross-country runner presented to the Mayo Clinic at age 18 years with complaints of progressive headache and visual disturbances. Neuroimaging revealed a heavily calcified left parieto-occipital mass with focal enhancement and remodeling of the overlying calvarium. INTERVENTION: A histological examination of the nearly gross total resection specimen disclosed a low-grade oligodendroglioma discretely abutting a superficially situated focus of pleomorphic xanthoastrocytoma. Ten months thereafter, a recurrence was suspected on the basis of the detection of a new focus of nodular enhancement. This lesion stabilized after radiation therapy, and the patient is well, without apparent residual disease 2.8 years after surgery. CONCLUSION: This unique neoplasm is presumed to represent a collision tumor, its biological behavior being similar to that of oligodendroglioma alone. However, the possibility of an unusual, mixed oligoastrocytoma with pleomorphic xanthoastrocytoma as the astrocytic component cannot be excluded entirely. Potentially, both components have the capacity for recurrence and anaplastic transformation.

Adolescent↗
PubMed2001

Carotid artery: elliptic centric contrast-enhanced MR angiography compared with conventional angiography.

PURPOSE: To determine the accuracy of elliptic centric contrast material-enhanced magnetic resonance (MR) angiography by using conventional angiography as the reference standard. MATERIALS AND METHODS: Fifty patients were examined prospectively with contrast-enhanced MR angiography and conventional angiography. The two examinations were performed within 1 week of each other. Two patients underwent conventional angiography of only one carotid artery, which yielded 98 arteries for comparison. RESULTS: With conventional angiography as the reference standard and by using a 70% threshold for internal carotid arterial diameter stenosis, maximum intensity projection (MIP) images had a sensitivity of 93.3%, specificity of 85.1%, and accuracy of 87.6%, whereas reformatted transverse source images had a sensitivity of 83.3%, specificity of 97.0%, and accuracy of 92.8%. Interobserver variability for conventional angiograms was 0.97, for MIP images was 0.91, and for source images was 0.90. The contrast-enhanced MR angiographic technique had a sensitivity of 88.9% and specificity of 58.1% for the presence of irregularity and/or ulceration. All 50 examinations were triggered appropriately so that minimal or no venous signal intensity was depicted. CONCLUSION: Contrast-enhanced elliptic centric three-dimensional MR angiography offers high-spatial-resolution, venous-suppressed images of the carotid arteries that appear to be adequate to replace conventional angiography in most patients examined prior to carotid endarterectomy.

Aged↗
PubMed1998

Arterial phase carotid and vertebral artery imaging in 3D contrast-enhanced MR angiography by combining fluoroscopic triggering with an elliptical centric acquisition order.

Arterial-phase three-dimensional (3D) contrast-enhanced MR angiograms of the carotid and vertebral arteries from their origins through the carotid bifurcations were obtained in 20 patients using acquisition times over 30 sec by using an MR fluoroscopy-triggered pulse sequence with elliptical centric view order. The typical pixel size was 0.8 mm (x) x 1.6 mm (y) x 1.5 mm (z), and 32-48 coronal slices were acquired. The fluoroscopic monitoring of bolus arrival was effective in 18 of the 20 cases; two failures were attributed directly to a poor choice of RF coil. To exploit peak arterial-to-venous contrast, the central 3D views were acquired first in the most compact time period possible for the given TR. For the 18 successfully triggered cases, arterial-phase 3D images were obtained with excellent venous suppression as demonstrated by an average internal jugular vein to common carotid signal enhancement ratio of only 0.05 +/- 0.04.

Adolescent↗