Association of vertebral end plate fracture with pediatric lumbar intervertebral disk herniation: value of CT and MR imaging.

A retrospective review of the radiologic findings in 31 patients less than 21 years old who underwent laminotomy for lumbar disk herniation revealed six cases of associated avulsion fracture of the vertebral end plate, a prevalence of 19%. All fractures were found in the 14-17-year-old subgroup (six of 19), a prevalence of 32%. In four patients, plain radiographs did not reveal the fracture. Computed tomographic (CT) findings were diagnostic in all six cases. Magnetic resonance (MR) images, obtained in three patients, demonstrated the avulsed cortical fragment and what are assumed to be the attached Sharpey fibers. On sagittal MR images, these structures had a configuration with the appearance of a "Y" or "7". Four of these six patients underwent bilateral laminotomies. The need for more extensive surgical resection may not be apparent at plain radiography or myelography but can be predicted with CT and MR imaging.

CT-guided thermocouple placement for hyperthermia treatment.

There is a well-documented synergistic cytotoxic effect when heat is combined with ionizing radiation. An integral component of hyperthermia treatments is the placement of thermocouple probes used for thermal dosimetry. With the surge in interest in the clinical use of hyperthermia, our department is performing an increasing number of thermocouple placements under computed tomographic (CT) guidance. We describe our technique for CT-guided thermocouple placement with two different systems: a trocar introduction system and a peel-away needle introduction system. We discuss the rationale for thermocouple placement, our early experience with this technique, and some potential complications.