Case-Control Study of Cephalometrics in Patients with Moyamoya

Negative Remodeling of Carotid Canal during Spontaneous Disease Progression in Moyamoya Disease

OBJECTIVE

This study was aimed to observe the changes in the carotid canal over time by measuring the carotid canal diameter longitudinally in adult patients with moyamoya disease in whom disease stage progressed spontaneously.

MATERIALS AND METHODS

Of 70 adult patients with moyamoya disease, 10 adult patients on 15 sides with spontaneous progression of the disease stage during conservative follow-up were included in this study. Other 10 moyamoya cases on 15 sides were selected as the controls without disease progression. All patients were followed up for at least 60 months after the progression of disease stage was confirmed. In addition, 5 patients who underwent microvascular decompression were included as healthy controls. The carotid canal diameter was measured with bone window CT and source images of TOF MR angiography at initial presentation, and then were serially monitored with the latter.

RESULTS

There was a significant correlation between the values obtained from CT and MRI (R²=0.992, P<0.001). The carotid canal diameter in moyamoya disease at initial presentation was 4.29±0.61 mm, being smaller than 5.20±0.51 mm in healthy controls (P<0.01). In response to disease progression, the carotid canal diameter started to decrease at 6 months after disease progression was confirmed, and reduced to about 85% of the original level during 60 months (P<0.01). However, the phenomenon was not observed in patients without disease progression.

CONCLUSIONS

The carotid canal diameter can decrease in response to disease progression even in adult moyamoya disease. "Negative" bone remodeling may play a key role in this unique phenomenon.