Evaluation of CT Changes in the Head and Neck After Cancer Treatment: Development of a Measurement Tool.

BACKGROUND: The late effect continuum of lymphedema and fibrosis (LEF) affects more than 70% of patients after treatment for head and neck cancer (HNC). LEF is associated with symptom burden and decreased function and quality of life. Although surveillance imaging is common posttreatment, objective assessment of soft tissues is not, likely due to the lack of objective evaluation methods and understanding of the significance of LEF. We undertook the development of a tool to measure LEF using CT scans in HNC patients. METHODS AND RESULTS: We developed a CT measurement tool assessing sites of soft tissue damage secondary to tumor, surgery, or radiation. The tool was applied to pre- and posttreatment CT scans for 10 HNC patients. The data were reviewed, and the initial tool was modified. Ten additional patients' scans were assessed using the revised tool. The tool was modified further after data review by an expert panel and was then applied to scans from all 20 patients. The final tool included 11 items as follows: grading of fat stranding at 6 sites (axial reconstruction images, scale 0-2), measurement of epiglottic thickness (sagittal images, scale mm), and measurement of prevertebral soft tissue thickness at C3 (sagittal images, scale mm). A total of 176 CT scans were evaluated from 20 patients (range 4-14 examinations/patient). Preliminary data demonstrated face validity. CONCLUSIONS: The final LEF assessment tool (CT-LEFAT) provides a standardized method for assessing critical sites that are involved by LEF. Studies to assess reliability and validity are ongoing.

The effects of methamphetamine on core body temperature in the rat--part 1: chronic treatment and ambient temperature.

RATIONALE: Stimulants such as methamphetamine (METH) alter core temperature in a manner that is dependent on ambient temperature and that shows tolerance after chronic use. Our objectives were to (1) determine whether tolerance to METH-induced hyperthermia was a consequence of neurotoxicity to dopamine or serotonin and (2) determine the relationship between ambient temperature and chronic treatment on the METH-induced temperature response. MATERIALS AND METHODS: Rats were treated with 1.0, 5.0, or 10.0 mg/kg METH at 24 degrees C (experiment 1) or treated with 5.0 mg/kg METH at 20 degrees C, 24 degrees C, or 28 degrees C (experiment 2). Treatment occurred for 12 days, and temperature measurements were made once per minute telemetrically during 7-h sessions in computer-regulated environments. RESULTS: Peak increases in core temperature occurred at 60 min post-treatment for the 1.0 and 10.0 mg/kg doses, and at 180 min for the 5.0 mg/kg dose. Tolerance-like effects were seen with chronic 5.0 (mixed results) and 10.0 mg/kg METH in the absence of dopamine or serotonin depletions measured 2 weeks after the completion of treatment. After 5.0 mg/kg METH, variations in ambient temperature resulted in an early flexible change in core temperature (phase 1) (hyperthermia at 28 degrees and hypothermia at 20 degrees ) and a later inflexible hyperthermia (phase 2). CONCLUSIONS: The results suggest that (1) the peak effect of different doses of METH occurs at different times (24 degrees ), (2) the diminished temperature response with chronic METH treatment was not associated with long-term dopamine and serotonin depletions, and (3) a two-phase temperature response to METH may reflect two independent mechanisms.