Learning Curve Associated with Complications in Biportal Endoscopic Spinal Surgery: Challenges and Strategies

STUDY DESIGN: Descriptions of technical strategies to overcome pitfalls associated with early learning periods in biportal endoscopic spinal surgery (BESS). PURPOSE: To introduce BESS for lumbar spinal diseases (LSDs) and to inform certain challenges to be overcome in mastering the technique. OVERVIEW OF LITERATURE: BESS has shown superior benefits including excellent magnification, a wider range of view by dynamic handling of an endoscope and instruments. Clinical reports, however, have not yet been very revealing for its new introduction into minimally invasive spine surgery. METHODS: To evaluate the learning curve for BESS, the procedures for various LSDs by one surgeon were analyzed in the view of shortening of the operating times and reduction of complications. Reviewing of recorded procedures helped in finding the reasons and the implemented solutions. RESULTS: The 68 cases included 25 for lumbar disc herniation (LDH), 3 for revision for recurred LDH, 39 for lumbar spinal stenosis (LSS) and 1 for synovial cyst. The operation time for the total cases averaged 83.7±33.6 minutes. According to diagnosis, it was 68.2±23.7 minutes for LDH. After the 14th case of LDH, it was nearly constant and close to the average time. One level of LSS needed 110.4±34.4 minutes. Prolonged operation times even in some later cases of LSS were mainly from struggling against blurred vision due to epidural bleeding. There were 7 cases of complications (10.3%) including 2 cases of dural tear, 1 case of root injury, and 4 cases of incomplete decompression on postoperative magnetic resonance imaging. There was no case of symptomatic hematoma or wound infection. CONCLUSIONS: BESS seemed to have a relatively short learning curve period. The overall complication rate in early learning period was 10.3%. These could be avoided by magnified regional views on an endoscope and a clear surgical field by controlling epidural bleeding.

An Analysis of Early Complications after Percutaneous Vertebroplasty in Elderly People

With the growing interests in the treatment of osteoporosis. percutaneous Vertebroplasty aimed at stabilizing and preventing progressiv eosteoporotic vertebral compression fracture has been tried. We analyzed 60 cases of vertebroplasty for senile osteporotic vertebvral compression fractures performed from April to August, 1999 at Wooridul Spine Hospital. We observed dramatic pain relief in almost cases within 6~72 hours(mean, 36 hours). Mean value of the Visual Analogue Scale(VAS) decreased from 8.3 to 2.8 after the procudure. The Operative complications were as follows ; epidural leakage(70 levels). Paraparesis(2 cases), Paravertebral venous leakage, Intradiscal leakage, foraminal leakage transient hypotension and transient apnea. This procedure is relatively safe and effective treatment modality for osteoporotic compression fracture. But much attention is required in selection of the cases such as severe crushing fracture, suspicions cortical fracture of the endplate and bursting fracture. The viscosity of the material and avoidance of rapid injection were important in preventing complications.

Differential Effect of Genistein and Calphostin C on Phospholipase C Activation and Cell Proliferation in T98G Human Glioblastoma and Hs 683 Human Glioma Cells

Amajor role in sustaining tumors like gliomas has been attributed to growth factors. Many questions remain unanswered about how such external signals are transduced into a transformed phenotype. Growth factors such as PDGF and epidermal growth factor(EGF) activate PLC, and this activation requires the intrinsic tyrosine kinase activity of the growth factor receptor. There are only a few reports on PKC activity in astrocytoma cells, especially in human glioma cells. We focused on signal transduction of phospholipase C(PLC) and phospholipase D(PLD) in human glioma cells. In this study, using genistein and calphostin C, the regulation of PLC, PLD, and PKC was investigated. The results are as follows; 1) Genistein is a selective inhibitor of PDGF-induced PLC- and PLD activation in T98G glioblastoma cells but not in Hs 683 glioma cells. 2) Calphostin-C stimulates PLC and PLD, possibly through a PKC-independent pathway in both T98G and Hs 683 cells. 3) Both genistein and calphostin-C inhibit glioma cell proliferation, indicating that the pathway for activation of PLC and PLD is not relevant to the pathway of cell proliferation in glioma cells.

An Occult Fracture in a Ankylosing Spondylitis Patient

A61-year-old head-injured patient exhibited acute onset of paraplegia during hospital in-care. Review of radiographs showed an occult linear transverse fracture line between the T11 and T12 vertebrae. An MRI scan performed after paraplegia showed compression of the spinal cord by a bony fragment. This case report presents a rare but devastating complication of an occult fracture at the T-L junction in patient with ankylosing spondylitis which was considered less significant due to more severe head injury. Thorough clinical and roentgenographic examination of the entire vertebral column is recommended in patients with ankylosing spondylitis who have sustained injury. Even if minor spinal trauma occurs in such clinical setting, the condition should be managed as a spinal fracture with potentially serious neurologic complications.

Von Hippel-Lindau Disease Manifestating as Recurrent Cerebellar Hemangioblastoma: A Case Report

Cerebellar hemangioblastoma comprises 2% of all brain tumors and 7% 10% of all posterior fossa tumors. It can arise in isolation("sporadic cases") or as a major manifestation of von Hippel-Lindau(VHL) disease, a well known autosomal dominant inherited tumor syndrome. Only 5-30% of these tumors are due to VHL disease. However, cerebellar hemangioblastoma occurs in younger patients, is often multiple and recurrent, and has a poorer prognosis than sporadic cases. We present a case of a 26-year-old woman with a right cerebellar hemangioblastoma, which recurred from a left cerebellar hemangioblastoma resected four years previously. Further evaluation established the diagnosis of VHL disease by demonstrating a cystadenoma in the pancreas and an omental cyst. Recently, the von Hippel-Lindau disease gene has been identified as a tumor suppressor gene and has been mapped to the short arm of chromosome 3(3p 25-26). Its absence or a defect in its structure is responsible for predisposition to the disease.