[Risk Factors for Predicting the Need for Additional Surgery for Symptomatic Adjacent Segment Disease after Minimally Invasive Surgery-Transforaminal Lumbar Interbody Fusion].

PURPOSE: To determine the incidence of and risk factors for symptomatic adjacent segment disease(SASD)requiring additional surgery in patients previously treated with minimally invasive surgery-transforaminal lumbar interbody fusion(MIS-TLIF)for degenerative lumbar disease. MATERIALS AND METHODS: A series of 467 consecutive patients who had undergone MIS-TLIF of one or two segments to treat degenerative lumbar disease was identified. The mean age of the patients at the time of the index operation was 67.7 years and the mean follow-up period was 33.2 months(range, 6.0-110.1 months). The incidence rate of SASD surgeries was calculated using the Kaplan-Meier method. The log-rank test and Cox regression analysis were used for risk factor analysis based on age, sex, number of fused segments, presence of laminectomy adjacent to index fusion, and L1 plumb line. RESULTS: The overall incidence rate of SASD requiring additional surgery was 2.8%. Kaplan-Meier analysis predicted a disease-free rate of adjacent segments in 94.3% of the patients at 4 years and in 90.8% of the patients at 8 years after the index operation. In the analysis of risk factors, a negative L1 plumb line was associated with a 5.6 times higher incidence of SASD requiring additional surgery than that associated with a positive L1 plumb line(p=0.0096). There was no significant difference in the survival rates based on age, sex, number of fused segments, and concomitant laminectomy to adjacent segment. CONCLUSION: Approximately 9.2% of the patients were predicted to undergo additional surgery for treating SASD within 8 years of MIS-TLIF. In this study, presence of a negative L1 plumb line indicated higher incidence of additional SASD associated surgeries than that shown by a positive L1 plumb line. Therefore, surgeons should carefully consider this factor while performing MIS-TLIF.

A Case of Aneurysmal Subarachnoid Hemorrhage with Middle Cerebral Artery Aplasia at 30 Weeks of Pregnancy.

Objective: We report a case of subarachnoid hemorrhage (SAH) that occurred at 30 weeks of pregnancy and was treated by coil embolization in a woman with middle cerebral artery (MCA) aplasia. Case Presentation: A 40-year-old woman who was 30 weeks pregnant presented to the emergency department with a half-day history of headache and nausea. She had sudden onset headache and her symptom did not improve. There was no neurological deficit. Head CT at the referring hospital revealed SAH. The fetal state was stable. There was no sign of threatened premature delivery. Head MRA revealed aplasia of the left MCA and aneurysm with a daughter sac at the A1 segment of the anterior cerebral artery (ACA). Head DSA revealed that the A1 aneurysm with a daughter sac arose from the anomalous collateral artery leading to a plexiform network. The diagnosis was SAH due to rupture of an A1 aneurysm. Performance of less invasive coil embolization seemed to be possible and was carried out under general anesthesia. The operation was completed after placing one coil and confirming that most of the aneurysmal dome was embolized, including the daughter sac. There was no cerebral vasospasm and no obvious neurological deficit. Antiplatelet drugs were only required for 10 days after the operation. Pregnancy was stable and the patient delivered a baby by cesarean section at 38 weeks of pregnancy. Conclusion: A rare case of aneurysmal SAH in a pregnant woman with MCA aplasia was successfully treated by endovascular surgery.