Chul-Hoon Chang

Analysis of Failed Spinal Cord Stimulation Trials in the Treatment of Intractable Chronic Pain

OBJECTIVE The purpose of this study is to identify the factors affecting the failure of trials (<50% pain reduction in pain for trial period) to improve success rate of spinal cord stimulation (SCS) trial. METHODS A retrospective review of the failed trials (44 patients, 36.1%) among the patients (n=122) who underwent SCS trial between January 1990 and December 1998 was conducted. We reviewed the causes of failed trial stimulation, age, sex, etiology of pain, type of electrode, and third party support. RESULTS Of the 44 patients, 65.9% showed unacceptable pain relief in spite of sufficient paresthesia on the pain area with trial stimulation. Four of six patients felt insufficient paresthesia with stimulation had the lesions of the spinal cord. Seventy five percent of the patients experienced unpleasant or painful sensation during stimulation had allodynia dominant pain. Third-party involvement, sex, age and electrode type had no influence on the outcome. CONCLUSION We conclude that SCS trial is less effective for patients with neuropathic pain of cord lesions, postherpetic neuropathy or post-amputation state. Further, patients with allodynia dominant pain can feel unpleasant or painful during trial stimulation.

The Effect of Premorbid Demographic Factors on the Recovery of Neurocognitive Function in Traumatic Brain Injury Patients

OBJECTIVE Premorbid demographic backgrounds of injured individuals are likely to reflect more accurately the status of patients with traumatic brian injury (TBI) than clinical factors. However, the concrete study about the relationship between the demographic factors and neurocognitive function in TBI patients has not been reported. The object of this study was to evaluate the effect of premorbid demographic factors on the recovery of neurocognitive function following TBI. METHODS From July 1998 to February 2007, 293 patients (male: 228, female: 65) with a history of head injury, who had recovered from the acute phase, were selected from our hospital to include in this study. We analyzed the effect of premorbid demographic factors including age, sex, educational level and occupation on the recovery of neurocognitive function in each TBI subgroup as defined by Glasgow Coma Scale (GCS) score. Intelligence and memory are components of neurocognitive function, and the Korean Wechsler Intelligence Scale (K-WAIS) and the Korean memory assessment scale (K-MAS) were used in this study. The results were considered significant at p<0.05. RESULTS The higher level of education was a good prognostic factor for intelligence regardless of GCS score and younger age group showed a better result for memory with an exception of severe TBI group. In the severe TBI group, the meaningful effect of demographic factors was not noted by the cause of influence of severe brain injury. CONCLUSION The demographic factors used in this study may be helpful for predicting the precise prognosis and developing an appropriate rehabilitation program for TBI patients.

Peritumoral Brain Edema in Meningiomas : Correlation of Radiologic and Pathologic Features

OBJECTIVE The primary objective of this study was to perform a retrospective evaluation of the radiological and pathological features influencing the formation of peritumoral brain edema (PTBE) in meningiomas. METHODS The magnetic resonance imaging (MRI) and pathology data for 86 patients with meningiomas, who underwent surgery at our institution between September 2003 and March 2009, were examined. We evaluated predictive factors related to peritumoral edema including gender, tumor volume, shape of tumor margin, presence of arachnoid plane, the signal intensity (SI) of the tumor in T2-weighted image (T2WI), the WHO histological classification (GI, GII/GIII) and the Ki-67 antigen labeling index (LI). The edema-tumor volume ratio was calculated as the edema index (EI) and was used to evaluate peritumoral edema. RESULTS Gender (p=0.809) and pathological finding (p=0.084) were not statistically significantly associated with peritumoral edema by univariate analysis. Tumor volume was not correlated with the volume of peritumoral edema. By univariate analysis, three radiological features, and one pathological finding, were associated with PTBE of statistical significance: shape of tumor margin (p=0.001), presence of arachnoid plane (p=0.001), high SI of tumor in T2WI (p=0.001), and Ki-67 antigen LI (p=0.049). These results suggest that irregular tumor margins, hyperintensity in T2WI, absence of arachnoid plane on the MRI, and high Ki-67 LI can be important predictive factors that influence the formation of peritumoral edema in meningiomas. By multivariate analysis, only SI of the tumor in T2WI was statistically significantly associated with peritumoral edema. CONCLUSION Results of this study indicate that irregular tumor margin, hyperintensity in T2WI, absence of arachnoid plane on the MRI, and high Ki-67 LI may be important predictive factors influencing the formation of peritumoral edema in meningiomas.

Subarachnoid Hemorrhage with Negative Baseline Digital Subtraction Angiography: Is Repeat Digital Subtraction Angiography Necessary?

Introduction Patients with negative initial digital subtraction angiography (DSA) are at significant risk for re-bleeding, which can lead to severe disability and death. The purpose of this study was to evaluate the necessity of repeat DSA in subgroups of patients with subarachnoid hemorrhage (SAH) with negative initial DSA. Methods A total of 904 spontaneous SAH patients were admitted to our department between May 2005 and May 2012. Twenty eight patients were selected for inclusion in this study because repeated DSA performed due to the etiology of the SAH could not be demonstrated on the initial DSA. According to the SAH pattern on initial computed tomography scans, patients were divided into perimesencephalic nonaneurysmal SAH (PN-SAH) and non PN-SAH (NPN-SAH) groups. Repeat DSA was performed in all patients, and two of these patients underwent a third DSA. Results Of the 904 patients, 28 patients (3.1%) had no vascular abnormality on initial DSA. Sixteen PN-SAH patients underwent a repeat DSA; however, no aneurysms were found. In contrast, 12 patients with NPN-SAH underwent repeat DSA, with detection of two cerebral aneurysms. Overall, the false-negative rate of the initial DSA was 7.1% (2/28 patients). No significant differences in false-negative results on initial DSA were observed between the PN-SAH and NPN-SAH groups. Conclusion In the line with the results of the current study, we should be highly suspicious of patients with a nonaneurysmal SAH, especially those with a NPN-SAH pattern. In order to reduce the morbidity and mortality resulting from a misdiagnosis, repeat DSA is necessary, and exclusion of an aneurysm is important.

Cerebellar Pilocytic Astrocytomas with Spontaneous Intratumoral Hemorrhage in Adult

Cerebellar pilocytic astrocytomas (PAs) are benign gliomas predominantly found in the pediatric population. Intracranial hemorrhages are extremely rare in initial presentations of cerebellar PAs. There are no reports in the medical literature of adult cerebellar PA cases presenting with intratumoral hemorrhage. We report 2 cases of adult cerebellar pilocytic astrocytomas with intratumoral hemorrhage. The first case is a 37-year-old woman presenting with severe headache, nausea, and vomitting. Computed tomography demonstrated an acute hemorrhage adjacent to the right cerebellar hemisphere and hydrocephalus. Magnetic resonance imaging (MRI) revealed a cerebellar vermian tumor with the hemorrhage as a mixed isointense area in the T2-weighted image, and as a mixed hyperintense area in the contrast-enhanced T1-weighted image. The second case is a 53-year-old man presenting with headache for 3 weeks. MRI revealed a cerebellar hemispheric tumor with the hemorrhage as a mixed hyperintense area. It had a cystic mass with a heterogeneous enhanced mural nodule in the gadolinium-enhanced T1-weighted image and a fluid-fluid level within the cyst in the T2-weighted image. Both of them underwent radical resections of their respective lesions. Histological examination of the specimens revealed typical astrocytoma, including a hemorrhagic portion. Both patients recovered postoperatively and continue to do well at present. The medical literature on hemorrhagic cerebellar PAs is also reviewed.

Cardiac troponin I elevation in patients with aneurysmal subarachnoid hemorrhage.

OBJECTIVE Cardiac dysfunction after aneurysmal subarachnoid hemorrhage (SAH) is associated with elevation of serum cardiac troponin I (cTnI) levels. Elevation of cTnI predicts cardiopulmonary and neurological complications, and poor outcome. METHODS We retrospectively reviewed the medical and radiologic records of 114 (male : 30, female : 84) patients who developed aneurysmal SAH between January 2006 and June 2007 and had no history of previous cardiac problems. We evaluated their electrocardiography and cTnI level, which had been measured at admission. A cTnI level above 0.5 microg/L was defined as an indicator of cardiac injury following SAH. We examined various clinical factors for their association with cTnI elevation and analyzed data using chi-square test, t-test and logistic regression test with SPSS version 12.0. The results were considered significant at p < 0.05. RESULTS THE FOLLOWING PARAMETERS SHOWS A CORRELATION WITH CTNI ELEVATION : higher Hunt-Hess (H-H) grade (p = 0.000), poor Glasgow Outcome Scale (GOS) score (p = 0.000), profound pulmonary complication (p = 0.043), higher heart rate during initial three days following SAH (p = 0.029), ruptured aneurysm on communicating segment of internal carotid artery (p = 0.025), incidence of vasospasm (p = 0.421), and duration of hyperdynamic therapy for vasospasm (p = 0.292). A significant determinants for outcome were cTnI elevation (p = 0.046) and H-H grade (p = 0.000) in a multivariate study. CONCLUSION A cTnI is a good indicator for cardiopulmonary and neurologic complications and outcome following SAH. Consideration of variable clinical factors that related with cTnI elevation may be useful tactics for treatment of SAH and concomitant complications.

Cubital Tunnel Syndrome, Associated With Synovial Chondromatosis

A 62-year-old female patient suffered from numbness and resting pain in the right ring and little fingers for 3 years. We confirmed cubital tunnel syndrome with electrodiagnostic study and performed the operation. We found seven firm consistent nodules, compressing the overlying the ulnar nerve, proximal to the medial epicondyle in the operation field. Histological finding showed synovial chondromatosis. We report a rare case of a patient with cubital tunnel syndrome caused by synovial chondromatosis.

Laparoscopic Treatment of Ventriculoperitoneal Shunt Complication Caused by Distal Catheter Isolation Inside the Falciform Ligament.

BACKGROUND A ventriculoperitoneal shunt is a widely recognized treatment that we use to treat hydrocephalus. In ones lifetime, there is a high possibility of being diagnosed with shunt dysfunction. Occasionally, complications caused by the distal catheter located in the intra-abdominal cavity may occur. CASE DESCRIPTION In this case, after undergoing shunt surgery, the patients distal catheter had not moved and was fixed in 1 place. Therefore, we used abdominal computed tomography and discovered the presence of a pseudocyst where the distal catheter was located. Through laparoscopic-assisted surgery performed by the department of general surgery, we discovered that the distal catheter entered into the falciform ligament and caused it to expand, creating a cyst. The fascia of the falciform ligament was dissected using a harmonic scalpel. Cerebrospinal fluid and the distal catheter were noted. Afterwards, the distal catheter was placed into the peritoneal cavity. After surgery, the patient was discharged without any complications. CONCLUSIONS Although this is an unusual circumstance, there have been reports of some cases in which the ventriculoperitoneal shunt distal catheter entered the falciform ligament. Therefore, one must pay close attention during the operation. In addition, when treatment is necessary, laparoscopic-assisted surgery might serve as an effective diagnostic and therapeutic modality.

Superficial Temporal Artery Pseudoaneurysm Treated with Manual Compression Alone

Traumatic pseudoaneurysm of the superficial temporal artery (STA) is an uncommon lesion and resection of the lesion is the treatment of choice. Three patients with traumatic pseudoaneurysm of the STA treated with only manual compression of the lesions were examined for this study. We report on an effective and safe minimally invasive technique for treatment of traumatic pseudoaneurysm of the STA.

Effect of Discontinuation of Anticoagulation in Patients with Intracranial Hemorrhage at High Thromboembolic Risk

Objective There was no abundance of data on the use of anticoagulant in patients with previous high risk of thromboembolic conditions under a newly developed intracranial hemorrhage in Korean society. The purpose of this study was to evaluate the safety of discontinuance and suggest the proper time period for discontinuance of anticoagulant among these patients. Methods We reviewed the medical records of 19 patients who took anticoagulant because of thromboembolic problems and were admitted to our department with newly developed anticoagulation associated intracranial hemorrhage (AAICH), and stopped taking medicine due to concern of rebleeding from January 2008 to December 2012. Analysis of the incidence of thromboembolic complications and proper withdrawal time of anticoagulant was performed using the Kaplan-Meier method. Results Our patients showed high risk for thromboembolic complication. The CHA2DS2-VASc score ranged from two to five. Thromboembolic complication occurred in eight (42.1%) out of 19 patients without restarting anticoagulant since the initial hemorrhage. Among them, three patients (37.5%) died from direct thromboembolic complications. Mean time to outbreak of thromboembolic complication was 21.38±14.89 days (range, 8-56 days). The probability of thromboembolic complications at 7, 14, and 30 days since cessation of anticoagulation was 0.00, 10.53, and 38.49%, respectively. Conclusion Short term discontinuance of anticoagulant within seven days in patients with AAICH who are at high embolic risk (CHA2DS2-VASc score >2) appears to be relatively safe in Korean people. However, prolonged cessation (more than seven days) may result in increased incidence of catastrophic thromboembolic complications.