The use of multiple time point dynamic positron emission tomography/computed tomography in patients with oral/head and neck cancer does not predictably identify metastatic cervical lymph nodes.

PURPOSE: To determine whether the time course of 18-fluorine fluorodeoxyglucose (18F-FDG) activity in multiple consecutively obtained 18F-FDG positron emission tomography (PET)/computed tomography (CT) scans predictably identifies metastatic cervical adenopathy in patients with oral/head and neck cancer. It is hypothesized that the activity will increase significantly over time only in those lymph nodes harboring metastatic cancer. PATIENTS AND METHODS: A prospective cohort study was performed whereby patients with oral/head and neck cancer underwent consecutive imaging at 9 time points with PET/CT from 60 to 115 minutes after injection with (18)F-FDG. The primary predictor variable was the status of the lymph nodes based on dynamic PET/CT imaging. Metastatic lymph nodes were defined as those that showed an increase greater than or equal to 10% over the baseline standard uptake values. The primary outcome variable was the pathologic status of the lymph node. RESULTS: A total of 2,237 lymph nodes were evaluated histopathologically in the 83 neck dissections that were performed in 74 patients. A total of 119 lymph nodes were noted to have hypermetabolic activity on the 90-minute (static) portion of the study and were able to be assessed by time points. When we compared the PET/CT time point (dynamic) data with the histopathologic analysis of the lymph nodes, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 60.3%, 70.5%, 66.0%, 65.2%, and 65.5%, respectively. CONCLUSIONS: The use of dynamic PET/CT imaging does not permit the ablative surgeon to depend only on the results of the PET/CT study to determine which patients will benefit from neck dissection. As such, we maintain that surgeons should continue to rely on clinical judgment and maintain a low threshold for executing neck dissection in patients with oral/head and neck cancer, including those patients with N0 neck designations.

Effect of spinal segment variants on numbering vertebral levels at lumbar MR imaging.

PURPOSE: To verify iliolumbar ligament (ILL) location, to evaluate magnetic resonance (MR) imaging morphologic features for detecting lumbosacral transitional vertebrae (TVs) (LSTVs), and to determine whether transitional situations are associated with anomalous vertebral numbering. MATERIALS AND METHODS: Investigational review board approval was obtained for this HIPAA-compliant retrospective study. A review of 147 subjects was performed by using spine radiography as the reference standard to determine total and segmental vertebral count and transitional anatomy. Thoracolumbar TVs (TLTVs) and LSTVs were identified. The lumbosacral intervertebral disk angle (LSIVDA), defined as the angle between the endplates, was measured, S1-2 disk morphology was rated according to the classification by O'Driscoll et al, and the ILL level was determined from MR images. Statistical analysis was performed by using χ(2) tests for dichotomous and ordinal variables and the t test for continuous variables. RESULTS: An anomalous total number of vertebrae were present in 12 (8.2%) of 147 subjects. The ILL was identified in 126 (85.7%) of 147 subjects and was present at L5 in 122 (96.8%) subjects; the remaining four (3.2%) subjects had an anomalous total number of vertebrae. A complete S1-2 intervertebral disk was associated with LSTVs (P = .004); however, LSIVDA was not (P = .2). TLTVs were present in six (4.1%) and LSTVs were present in 22 (15.0%) of 147 subjects. Both were present in four (2.7%) subjects. The presence of a TLTV was associated with a higher incidence of a concomitant LSTV and vice versa (P < .001; odds ratio [OR], 13.7; 95% confidence interval [CI]: 2.7, 68.4]). A TLTV was not associated with an anomalous total number of vertebrae (P = .46), but an LSTV was (P < .001; OR, 7.4; 95% CI: 2.2, 24.8). CONCLUSION: The ILL denotes the lowest lumbar vertebra, which does not always represent L5. A well-formed, complete S1-2 intervertebral disk is associated with LSTVs, but alteration in LSIVDA is not. LSTVs are associated with anomalous vertebral numbering.

Imaging of the paranasal sinuses and in-office CT.

Since the introduction of functional endoscopic sinus surgery (FESS) in the United States in 1985, the information gained from imaging has proved imperative in understanding regional morphology and guidance of surgical procedures. More than 20 years later, the importance of imaging continues to be the anatomic detail afforded by this technology, the roadmap it provides in planning the surgery, and the morphologic detail it provides in recurrent disease. The latest development in CT technology, cone beam CT instrumentation, may change the way imaging of the nasal cavity and paranasal sinuses is performed in the future. These topics are discussed in this article.