Improvement of Orbitofrontal Cortex Function Associated with Blephrospasm Symptom Remission.

OBJECTIVE

To determine whether orbitofrontal cortex (OFC) function improves with blepharospasm (BSP) symptom remission using a verbal fluency task and near-infrared spectroscopy (NIRS).

METHODS

Nineteen BSP patients and 9 healthy controls (HCs) matched by gender and education were examined using NIRS. The BSP patients were divided into 2 groups based on the onset or remission of BSP symptoms. A covariance analysis was conducted to analyze the differences among the 3 groups to avoid the influence of different ages. The least significant difference was used to process the post hoc test.

RESULTS

The hemoglobin concentration and cerebral blood flow of the bilateral orbitofrontal area (channels 27, 31, 34, 37, and 39) were not significantly different between the BSP remission and HC groups (p > 0.05); however, both groups were significantly increased compared with the BSP onset group (BSP remission group vs. BSP onset group: p = 0.003, p = 0.018, p = 0.013, p = 0.001, and p = 0.011, respectively; BSP remission group vs. BSP onset group: p = 0.037, p = 0.044, p = 0.023, p = 0.016, and p = 0.025, respectively).

CONCLUSION

This is the first investigation to control for symptom stages in BSP patients examined via NIRS. Cognitive ability and OFC function improve with BSP symptom remission. Thus, the OFC may be inter-connected with motor and cognitive symptoms in BSP.