Sphenoid Ridge in Trisomy 21: A CT-Based Morphometric Evaluation

To examine variations in the morphology of the sphenoid ridge (SR) between individuals with trisomy 21 (T21) and healthy controls.

The work included computed tomography scans from 45 patients with T21 (mean age: 9.40±3.87 y) and 45 healthy controls (mean age: 8.56±4.87 y). Measurements were taken for SR in terms of its length (LSR), angle (ASR), lateral tip width (WL), and midline width (WML). ASR was categorized as follows: Type A for values >130 degrees, Type B for values between 110 and 130 degrees, and Type C for values <110 degrees.

In the T21 group, LSR, ASR, WL, and WML were measured as 40.07±3.83 mm, 119.58±10.08 degrees, 2.65±0.90 mm, and 9.09±2.45 mm, respectively. In controls, LSR, ASR, WL, and WML were measured as 42.28±4.26 mm, 122.50±8.67 degrees, 2.62±0.80 mm, and 7.95±2.08 mm, respectively. LSR (P<0.001) and ASR (P=0.039) were found to be smaller in individuals with T21 compared with the control group. WML was greater in T21 than controls (P=0.019), but WL was statistically similar in both groups (P=0.812). The comparison of ASR configurations between the T21 group (types A: 8.9%, B: 76.7%, and C: 14.4%) and the control group (types A: 17.8%, B: 72.2%, and C: 10%) indicated no significant association between T21 and this classification (P=0.173).

LSR and ASR could correspond to anterior fossa width and middle fossa depth, respectively. As a result, patients with T21 tend to have a narrower anterior fossa and a shallow middle fossa.