Comprehensive radionuclide esophagogastrointestinal transit study: methodology, reference values, and initial clinical experience.

UNLABELLED: A radionuclide methodology and reference values have been developed for a single gastrointestinal transit study including esophageal transit, liquid and solid gastric emptying, and small- and large-bowel transit, using (111)In-diethylenetriaminepentaacetic acid (DTPA) with the standardized (99m)Tc-labeled solid meal. METHODS: Eighteen healthy subjects and 18 patients were investigated. The esophageal transit study was performed with 3.7 MBq (0.1 mCi) of (111)In-DTPA in 15 mL of water. A liquid-only 30-min gastric-emptying study followed, with ingestion of 3.7 MBq (0.1 mCi) of (111)In-DTPA in 300 mL of water. Then, a simultaneous solid-liquid emptying study was acquired after ingestion of a solid (99m)Tc-sulfur colloid-labeled meal and 7.4 MBq (0.2 mCi) of (111)In-DTPA in 120 mL of water. Images were acquired intermittently for 4 h. Additional (111)In images were acquired at 5 and 6 h to measure small-bowel transit, and at 24, 48, and 72 h for large-bowel transit. RESULTS: Reference values were determined for esophageal transit (transit time, percentage emptying at 10 s), liquid-only gastric emptying (emptying half-time), liquid and solid emptying in a dual-phase solid-liquid study (emptying half-time and percentage emptying at 1, 2, 3, and 4 h), small-bowel transit index (percentage transit to ileocecal valve at 6 h), and colonic transit (geometric center and percentage colonic emptying) at 24, 48, and 72 h. Results from the first 18 patients found abnormal transit in 72% (13/18); clinical management changed in 61% (11/18). CONCLUSION: We have developed a radionuclide methodology and derived reference values for a comprehensive gastrointestinal transit study using (111)In-DTPA with the standardized (99m)Tc-labeled solid meal. Our initial clinical experience suggests clinical value.

Value of imaging in head and neck tumors.

In this review, the value of imaging in the management of head and neck tumors is summarized. The many diverse tumors of the head and neck are grouped for purposes of staging and treatment. The groupings of malignancies consist of sinonasal, nasopharynx, salivary gland, oral cavity, oropharynx, hypopharynx, larynx, and thyroid tumors. The anatomy, rationale for choice of imaging modality, interpretation of acquired images, staging, treatment options, and posttherapy assessment are discussed.

Follow-up or Surveillance (18)F-FDG PET/CT and Survival Outcome in Lung Cancer Patients.

UNLABELLED: The value of performing follow-up PET/CT imaging more than 6 mo after the conclusion of therapy-either as a routine practice or because of clinically suspected recurrence-is not well established. The purpose of this study was to evaluate the added value of follow-up PET/CT to the clinical assessment and survival outcome of lung cancer patients. METHODS: This was a retrospective study of 261 biopsy-proven lung cancer patients at a single tertiary center. In total, 488 follow-up PET/CT scans done 6 or more months after the completion of initial treatment were included in this study. Median follow-up from the completion of primary treatment was 29.3 mo (range, 6.1-295.1 mo). Overall survival (OS) benefit was measured using Kaplan-Meier plots with a Mantel-Cox log-rank test. A multivariate Cox regression model was provided with clinical covariates. RESULTS: Of the 488 PET/CT scans, 281 were positive and 207 negative for recurrence. Overall median survival from the time of the PET/CT study was 48.5 mo. The median survival of PET-positive and PET-negative groups was 32.9 and 81.6 mo, respectively (P < 0.0001). A subgroup analysis demonstrated a similar difference in OS for 212 scans completed between 6 and 24 mo after treatment (P = 0.0004) and 276 scans completed after 24 mo (P = 0.0006). In the context of clinical assessment, PET/CT identified recurrence in 43.7% (107/245) of scans without prior clinical suspicion and ruled out recurrence in 15.2% (37/243) of scans with prior clinical suspicion. There was a significant difference in OS when grouped by clinical suspicion (P = 0.0112) or routine follow-up (P < 0.0001). In a multivariate Cox regression model, factors associated with OS were age (P < 0.0001) and PET/CT result (P = 0.0003). An age-stratified subgroup analysis demonstrated a significant difference in OS by PET scan result among patients younger than 60 y and between 60 and 70 y but not in those older than 70 y (P < 0.0001, P = 0.0004, and P = 0.8193, respectively). CONCLUSION: (18)F-FDG PET/CT performed for follow-up more than 6 mo after the completion of primary treatment adds value to clinical judgment and is a prognostic marker of OS in lung cancer patients, regardless of the timing of the follow-up scan, and especially in patients younger than 70 y.

Postoperative temporalis muscle atrophy and the use of electrocautery: a volumetric MRI comparison.

Postoperative temporalis muscle atrophy from injury to the neurovascular supply can cause significant cosmetic disfigurement, and avoidance of electrocautery use has become a common practice in minimizing this outcome. We attempted to quantify the effects of electrocautery on temporalis atrophy by retrospectively reviewing postoperative magnetic resonance images in patients having undergone an orbital frontal craniotomy. We reviewed medical records and compared volumetric measurements of the temporalis muscle in 25 patients using the contralateral temporalis muscle as an internal control. The mean size of the nonsurgical temporalis muscle was 24.6 cm(3) as compared with 23.6 cm(3) on the operated side. The difference of 1.0 cm(3) was not statistically significant (p = 0.32). The only postoperative atrophy noted visually on the magnetic resonance images developed in the posterior superior aspect of the temporalis muscle, behind the vertical incision of the temporalis muscle. In the small control group, with known injury to V3, the mean nonsurgical size was 27.7 cm(3), whereas it was 16.5 cm(3) on the contralateral surgical side. The difference of 11.2 cm(3) was statistically significant (p = 0.04). These findings suggest that the use of electrocautery to dissect the temporalis muscle does not significantly contribute to atrophy provided careful surgical technique is practiced.