Fletcher, Geoffrey P.

AbstractBackgroundMargins in transoral surgery for tonsil cancer can be limited by oropharyngeal wall thickness (OWT), but the normal range is not well established.MethodsIn 240 noncancer subjects, OWT was measured bilaterally in the vicinity of the tonsils with MRI. Statistical analysis was performed to assess for interaction of age, sex, location, and obesity.ResultsMean(SD) OWT measured 3.4(0.6) mm posteriorly, 3.7(2.0) mm between the styloglossus and stylopharyngeus, and 5.3(0.8) mm laterally. OWT was greater in men, correlated with obesity, decreased posteriorly and laterally in the 60–80 versus 40–59 year age groups, and increased when styloglossus/stylopharyngeus were closer. OWT was <5 mm in 36.7%–97.9% of locations, with the largest percentage below this threshold located posteriorly.ConclusionsOWT is frequently <5 mm, particularly in the posterior and intermuscular areas, suggesting that a smaller surgical margin may need to be accepted in transoral tonsil cancer surgery for anatomic reasons.

Objective: Evaluate prevalence and pattern of occipital pneumatization (OP). Patients: Individuals with imaging evidence of OP on computed tomography (CT). Intervention(s): High resolution CT scans of the temporal bone. Main Outcome Measure: The prevalence and pattern of OP on 1000 CT scans performed at a large academic healthcare system. Results: OP had a prevalence of 11.8% (n = 118) while occipital condyle pneumatization occurred in only 0.3%. Occipital air cells were right-sided in 27.1% (n = 32), left-sided in 51.7% (n = 61), and bilateral in 21.2% (n = 25), and OP was contiguous with the occipitomastoid suture. In cases of unilateral OP, the contralateral jugular foramen demonstrated relative enlargement ( p = 0.006), but a direct association could not be established. Conclusions: The occipital bone is an accessory site of skull base pneumatization in 11.8% of the population undergoing temporal bone CT, while air cell extension into the occipital condyle occurs more rarely. These occipital air cells have a left-sided predilection and are always in direct proximity to the occipitomastoid suture, suggesting developmental egress from the mastoid. OP is a normal variant and lacks features of craniocervical pneumatization, which is a rare disorder.