Inter-Racial, Gender and Aging Influences in the Length of Anterior Commissure-Posterior Commissure Line

OBJECTIVE: The length of anterior-posterior commissure (AC-PC) in racial groups, age, gender of patients with deep brain stimulation (DBS) and pallidotomy were investigated. METHODS: From January 1996 to December 2003, 211 patients were treated with DBS and pallidotomy. There were 160 (76%) Caucasians, 35 (17%) Hispanics, 12 (5%) Asians and 4 Blacks (2%). There were 88 males and 52 females in DBS-surgery group and 44 males, 27 females in pallidotomy group. Mean age was 58 year-old. There were 19 males and 19 females and mean age was 54.7 years in the control group. Measurements were made on MRI and @Target software. RESULTS: The average AC-PC distance was 24.89 mm (range 32 to 19), which increased with aging until 75 years old in Caucasian and also increased with aging in Hispanic, but the AC-PC distance peaked at 45 years old in Hispanic. The order of AC-PC distance were 25.2+/-2 mm in Caucasian, 24.6+/-2.24 mm in Asian, 24.53 mm in Black, 23.6+/-1.98 mm in Hispanic. The average AC-PC distance in all groups was 24.22 mm in female who was mean age of 56.35, 25.28 mm in male who was mean age of 60.19 and 24.5+/-2 mm in control group that was excluded because of the difference of thickness of slice. According to multiple regression analysis, the AC-PC distance was significantly correlated with age, race, and gender. CONCLUSION: The AC-PC distance is significantly correlated with age, gender, and race. The atlas of functional stereotaxis would be depended on the variation of indivisual brain that can influenced by aging, gender, and race.

Shift of the Brain during Functional Neurosurgery

OBJECTIVE: The study investigates the extent of brain shift and its effect on the accuracy of the stereotaxic procedure. METHODS: Thirty-five patients underwent 40stereotactic procedures between June 2002 and March 2004. There were 26 males, mean age 59years old. There were 34procedures for Parkinson's disease, 2 for essential tremor, 3 for cerebral palsy, 1 for dystonia. Patients were divided in four groups based on postoperative pneumocephalus: under 5cc (9 procedures), between 5~10cc (13procedures), between 10~15cc (11procedures) and more than 15cc (7procedures). The coordinates of the anterior commissure(AC), posterior commissure(PC), and target were defined in pre-and intraoperative magnetic resonance image scans and the amount of air volume was measured with @Target (BrainLab, Heimstetten, Germany). RESULTS: The mean AC-PC was 26.5mm for patients with less than 5cc, 26.9mm for 5~10cc, 25.8mm for 10~15cc and 26.2mm for more than 15cc. The length of AC-PC line and coordinates of AC, PC was also not statistically different, Euclidean distance as well as delta x, delta y, delta z of AC, PC, and target were also not statistically different among the groups (p<0.1). There was a variance in target of 0.7~7.6mm, Euclidean distance of 2.5mm, related to electrophysiology but not to brain-shift. CONCLUSION: The amount of air accumulated in the intracranial space and compressing the cortical surface has no effect on the localization of subcortical stereotactic target and landmarks.

Bilateral Pallidotomy for Dystonia with Glutaric Aciduria Type 1

Glutaric aciduria type 1 is an inborn error of lysine, hydroxylysine, and tryptophan metabolism caused by deficiency of glutaryl-coenzyme A dehydrogenase. The disease often appears in infancy with encephalopathy episode that results in acute basal ganglia and white matter degeneration. The majority of patients develop a dystonic-dyskinetic syndrome. This reports 6year-old boy who had been done previous gastrostomy due to swallowing difficulty underwent bilateral pallidotomy with intraoperative electromyography(EMG) monitoring for disabling dystonia. Intraoperative EMG was used to assess stimulation thresholds required for capsular responses and muscle tone. Surface EMG electrodes were placed on the face and cricopharyngeal muscles. Exact target were directly modified according to MRI-visualized anatomy. EMG response was consistently seen prior to visual observation of muscle activity. The surgery improved dystonic symptoms without swallowing difficulty.