Incontinence & Female Urology & Neurourology(구연) (NP-047) Urological outcome of untethering surgery for patients of occult spina bifida whose initial symptom developed in adulthood 연세대학교 의과대학 비뇨의학교실 손희서,김장환 Introduction and Objective : Most of spina bifida are diagnosed early in life. However, even in the modern era of advanced medicine, some rare cases of occult spina bifida (OSB) are missed in early detection, and go well until their adulthood without any neuro-urological symptom (named, adult onset tethered cord syndrome (AOTCS)). Little is known on the prognosis of AOTCS. We have investigated the impact of untethering surgery and symptom duration on the urodynamic disorder in AOTCS. Materials and Methods : OSB patients whose initial symptom had developed in adulthood were evaluated. Preoperative (Pre-Op) urodynamic studies were performed just before untethering. Postoperative (Post-Op) urodynamic studies were performed at least three months after untethering. Pre and Post-Op urodynamic parameters and duration of symptom was analyzed using Spearman Rank correlation test and Wilcoxon Signed Rank test. Results : 26 patients (male 9, female 17) were evaluated. The median age at symptom onset was 34.9 (18.0~54.7), the median age at untethering was 42.0 (18.4~67.2). The median time interval between symptom onset and untethering was 29.9 (1.1~249.4) months. There was no significant correlation between symptom duration and Pre-Op urodynamic parameters; bladder compliance (BC) (rho=-.118, P=0.566), maximum cystometric capacity (MCC) (rho=.037, P=0.859), detrusor pressure (Pdet) at end-filling (rho=.095, P=0.645), and post-void residual urine volume (PVR) per MCC (rho=.208, P=0.308). For 18 patients, Post-Op urodynamic studies were performed at median period of 31.3 (3.2~124.8) months after untethering. On analysis of Pre and Post-Op urodynamic parameters, significant correlation was observed in BC (rho=.614, P=0.007), Pdet at end-filling (rho=.484, P=0.042), and PVR/MCC (rho=.592, P=0.010). However, there was no correlation in MCC (rho=.271, P=0.276). There was no significant change in BC (P=0.777), MCC (P=0.112), Pdet at end-filling (P=0.979) after untethering. Conclusion : In patients with OSB whose initial symptom developed in adulthood, the duration of symptom had not significant impact on the urodynamic parameters at initial diagnosis. As there was significant correlation of urodynamic parameters before and after surgery, without significant difference, untethering might not be beneficial in correcting the urodynamic disorder of AOTCS. keywords : Adult, Spina Bifida Occulta, urodynamics