Frequency and clinical relevance of PET/CT incidentalomas.

RATIONALE AND OBJECTIVES: To assess the frequency of clinically significant incidental CT findings on PET/CT. MATERIALS AND METHODS: Reports of 345 cases of baseline standard skull base to thighs PET/CT exams done over the course of a 6 month period at an outpatient facility affiliated with a large tertiary care level 1 trauma medical center were retrospectively reviewed. Incidental CT findings were assigned a level of clinical significance on a scale of 1-5, from doubtful significance to very significant. CT findings already known from prior CT reports were not included. CT findings corresponding to PET findings were also excluded. A score of 3 or greater was considered significant and reportable. RESULTS: Out of 345 cases, 171 (50%) had a least one CT finding rated at or above a score of 3 on our scale of significance, while 96 (28%) were found to have at least one CT finding with score at or above 4, and 25 cases (7%) showed at least one CT finding rated 5. CONCLUSION: A substantial percentage of baseline PET/CT studies contain previously undiagnosed, significant incidental findings on the CT images.

Findings on MR sleep studies as biomarkers to predict outcome of genioglossus advancement in the treatment of obstructive sleep apnea in children and young adults.

OBJECTIVE: Genioglossus advancement, an operation to pull the tongue anteriorly, is a treatment of obstructive sleep apnea (OSA) secondary to glossoptosis. MRI predictors to identify which children will benefit from genioglossus advancement would be helpful for planning. We reviewed imaging findings on MR sleep studies as biomarkers to predict success or failure of genioglossus advancement in the treatment of OSA in children and young adults. MATERIALS AND METHODS: Twenty-eight patients who had undergone genioglossus advancement and preoperative MRI were identified. For each subject, genioglossus advancement, which was performed to treat OSA, was categorized as a success or failure on the basis of polysomnography and clinical criteria. Static and dynamic cine MR sequences were retrospectively evaluated for multiple parameters including measurements of the size of the tongue and of the bony confines of the supraglottic airway, the ratio of tongue size to bony confines size, static size and dynamic changes of the retroglossal airway, tonsil size, and soft palate thickness. Radiologists were blinded to the outcome of genioglossus advancement (i.e., success or failure category). Numeric biomarkers were compared in an analysis-of-covariance model adjusting for patient age. RESULTS: Genioglossus advancement was successful for the treatment of OSA in 17 patients and failed in 11 patients. The relative size of the tongue (tongue-bony confines ratio) was larger in patients with a successful surgical outcome than in those for whom the procedure failed (mean ratio, 0.51 vs 0.46; p = 0.023). Smaller adenoids were associated with a successful outcome (mean size of adenoids, 9.1 vs 12.4 mm; p = 0.049). No other biomarker-including absolute tongue size and airway size or dynamic airway motion-was significant. CONCLUSION: The relative (not absolute) tongue size and small size of the adenoid tonsils on MRI were predictors of success of genioglossus advancement for the treatment of glossoptosis causing OSA. These findings may be helpful in guiding surgical decision making in children with OSA.