Dong Jun Lim

Radiologic Assessment of Subsidence in Stand-Alone Cervical Polyetheretherketone (PEEK) Cage

OBJECTIVEnAim of study was to find a proper method for assessing subsidence using a radiologic measurement following anterior cervical discectomy and fusion (ACDF) with stand-alone polyetheretherketone (PEEK), Solistrade mark cage.nnnMETHODSnForty-two patients who underwent ACDF with Solistrade mark cage were selected. With a minimum follow-up of 6 months, the retrospective investigation was conducted for 37 levels in 32 patients. Mean follow-up period was 18.9 months. Total intervertebral height (TIH) of two fused vertebral bodies was measured on digital radiographs with built-in software. Degree of subsidence (DeltaTIH) was reflected by the difference between the immediate postoperative and follow-up TIH. Change of postoperative disc space height (CT-MRDeltaTIH) was reflected by the difference between TIH of the preoperative mid-sagittal 2D CT and that of the preoperative mid-sagittal T1-weighted MRI.nnnRESULTSnCompared to preoperative findings, postoperative disc height was increased in all cases and subsidence was observed only in 3 cases. For comparison of subsidence and non-subsidence group, TIH and CT-MRDeltaTIH of each group were analyzed. There was no statistically significant difference in TIH and CT-MRDeltaTIH between each group at 4 and 8 weeks, but a difference was observed at the last follow-up TIH (p=0.0497).nnnCONCLUSIONnACDF with Solistrade mark cage was associated with relatively good radiologic long-term results. Fusion was achieved in 94.5% and subsidence occurred in 8.1% by the radiologic assessment. Statistical analysis reveals that the subsidence seen later than 8 weeks after surgery and the development of subsidence does not correlate statistically with the change of the postoperative disc space height.

Risk factors of delayed surgical evacuation for initially nonoperative acute subdural hematomas following mild head injury

BackgroundAlthough the majority of patients with minimal acute subdural hematomas (aSDHs) can be managed conservatively, some require delayed aSDH evacuation due to hematoma enlargement. This study was designed to determine the risk factors associated with delayed hematoma enlargement leading to surgery in patients with aSDHs who did not initially require surgical intervention.MethodsFrom 2002 to 2012, 98 patients were treated for nonoperative aSDHs following mild head injury (Glasgow Coma Scale scores of 13–15). The outcome variables were radiographic evidence of SDH enlargement on serially obtained computed tomography (CT) images and later surgical evacuation. Univariate and multivariate analyses were applied to both the demographic and initial radiographic features to identify risk factors for SDH progression and surgery.ResultsOverall, 64 patients (65xa0%) revealed minimal SDH or spontaneous hematoma resolution (conservative group) with conservative management at their last follow-up CT scan. The remaining 34 patients (35xa0%) received delayed hematoma evacuation (delayed surgery group) a median of 17xa0days after the head trauma. There were no significant differences between the two groups for baseline characteristics, including age, injury type, degree of brain atrophy, prior history of antithrombotic drugs, and coagulopathy. The presence of cerebral contusions and subarachnoid hemorrhages was more common in the conservative group (pu2009=u20090.003 and pu2009=u20090.003, respectively). On multivariate analysis, hematoma volume (pu2009=u20090.01, odds ratio [OR]u2009=u20091.094, 95xa0% confidence interval [CI]u2009=u20091.021–1.173) and degree of midline shift (pu2009=u20090.01, ORu2009=u20091.433, 95xa0% CIu2009=u20091.088–1.888) on the initial CT scan were independently associated with delayed hematoma evacuation.ConclusionsA critical proportion of patients with minimal aSDHs occurring after mild head injury can progress over several weeks and require hematoma evacuation. Especially patients with a large initial SDH volume and accompanying midline shift require careful monitoring of hematoma progression.

Biomechanical study of lumbar spinal arthroplasty with a semi-constrained artificial disc (activ L) in the human cadaveric spine.

OBJECTIVEnThe goal of this study was to evaluate the biomechanical features of human cadaveric spines implanted with the Activ L prosthesis.nnnMETHODSnFive cadaveric human lumbosacral spines (L2-S2) were tested for different motion modes, i.e. extension and flexion, right and left lateral bending and rotation. Baseline measurements of the range of motion (ROM), disc pressure (DP), and facet strain (FS) were performed in six modes of motion by applying loads up to 8 Nm, with a loading rate of 0.3 Nm/second. A constant 400 N axial follower preload was applied throughout the loading. After the Activ L was implanted at the L4-L5 disc space, measurements were repeated in the same manner.nnnRESULTSnThe Activ L arthroplasty showed statistically significant decrease of ROM during rotation, increase of ROM during flexion and lateral bending at the operative segment and increase of ROM at the inferior segment during flexion. The DP of the superior disc of the operative site was comparable to those of intact spine and the DP of the inferior disc decreased in all motion modes, but these were not statistically significant. For FS, statistically significant decrease was detected at the operative facet during flexion and at the inferior facet during rotation.nnnCONCLUSIONnIn vitro physiologic preload setting, the Activ L arthroplasty showed less restoration of ROM at the operative and adjacent levels as compared with intact spine. However, results of this study revealed that there are several possible theoretical useful results to reduce the incidence of adjacent segment disease.

Risk of Stroke with Temporary Arterial Occlusion in Patients Undergoing Craniotomy for Cerebral Aneurysm

OBJECTIVEnThis study was performed to elucidate the technical and patient-specific risk factors for postoperative ischemia in patients undergoing temporary arterial occlusion (TAO) during the surgical repair of their aneurysms.nnnMETHODSnEighty-nine consecutive patients in whom TAO was performed during surgical repair of an aneurysm were retrospectively analyzed. The demographics of the patients were analyzed with respect to age, Hunt and Hess grade on admission, Fisher grade of hemorrhage, aneurysm characteristics, timing of surgery, duration of temporary occlusion, and number of temporary occlusive episodes. Outcome was analyzed at the 3-month follow-up, along with the occurrence of symptomatic and radiological stroke.nnnRESULTSnIn overall, twenty-seven patients (29.3%) had radiologic ischemia attributable to TAO and fifteen patients (16.3%) had symptomatic ischemia attributable to TAO. Older age and poor clinical grade were associated with poor clinical outcome. There was a significantly higher rate of symptomatic ischemia in patients who underwent early surgery (p = 0.007). The incidence of ischemia was significantly higher in patients with TAO longer than 10 minutes (p = 0.01). In addition, patients who underwent repeated TAO, which allowed reperfusion, had a lower incidence of ischemia than those who underwent single TAO lasting for more than 10 minutes (p = 0.011).nnnCONCLUSIONnDuration of occlusion is the only variable that needs to be considered when assessing the risk of postoperative ischemic complication in patients who undergo temporary vascular occlusion. Attention must be paid to the patients age, grade of hemorrhage, and the timing of surgery. In addition, patients undergoing dissection when brief periods of temporary occlusion are performed may benefit more from intermittent reperfusion than continuous clip application. With careful planning, the use of TAO is a safe technique when used for periods of less than 10 minutes.

Atypical Noncontiguous Multiple Spinal Tuberculosis: A Case Report

Objective Spinal tuberculosis-associated symptoms are not so unique as to immediately indicate the proper diagnosis in most cases. Distinguishing spinal tuberculosis (Potts disease) from pyogenic spondylitis is often difficult, and lesions metastatic from systemic malignancy are the other major entity from which spinal tuberculosis must be distinguished. Clinical Presentation A 27-year-old male patient presented with a history of back pain after a minor trauma 1 month ago. Computed tomography and magnetic resonance imaging of the thoracic spine showed multiple osteolytic bone lesions at the bodies of T9, T10 and T11 vertebrae and the spinous processes of T12 and L1. Other noncontiguous osteolytic lesions were noted at S2 body and right sacro-iliac joint. Intervention To confirm the pathologic diagnosis, the patient underwent an open biopsy for the T12 and L1 spinous process lesions and a percutaneous transpedicular biopsy on T9, T10, T11 lesions. Frozen biopsy was reported as compatible with chronic granulomatous caseating necrosis without malignant cells. The final diagnosis was an atypical presentation of multiple spinal tuberculosis. The patient received an appropriate enteral anti-tuberculosis therapy and recovered without any complications. Follow-up MRI taken after a year of medical treatment revealed marked resolution of the lesions. Conclusion Current research indicates the incidence of multi-level noncontiguous, remote vertebral tuberculosis is 1.1% to 16%. Because tuberculous spondylitis could represent variant and atypical pattern, the disease should be considered in differential diagnosis along with other diseases such as metastatic neoplasm, pyogenic spondylitis, especially when the radiologic studies are revealing multiple spinal lesions.

Analysis of multiple factors affecting surgical outcomes of proximal middle cerebral artery aneurysms.

OBJECTIVEnWe analyzed multiple factors including anatomical characteristics that influence the surgical outcomes of proximal middle cerebral artery (M1) aneurysms.nnnMETHODSnBetween January 1999 and February 2007, 189 patients had middle cerebral artery aneurysms and 60 had M1 aneurysms. Eleven patients were excluded from this study. The aneurysms were classified into two groups (superior- and inferior-wall type). Retrospectively, we evaluated characteristics of these patients and investigated factors affecting surgical outcomes.nnnRESULTSnOf the 49 patients, 28 had ruptured aneurysms and 43 had aneurysms sized less than 10mm in diameter. There were no giant aneurysms, the incidence of multiple aneurysms was high (22 patients, 45%), and intracerebral hematomas (ICH) were recognized in 13 patients (27%). The superior-wall group included 29 patients (59.2%) and the inferior-wall group had 20 (40.8%). Overall mortality and morbidity rates were 6.1% and 24.5%, respectively. Thirty-four patients (69%) showed good outcomes (GOS 4-5). Eleven and five patients showed unfavorable outcomes from the superior- and inferior-wall group, respectively. Of the four operation-related morbidity patients, three were from the superior-wall and one from the inferior-wall group. There were no statistically significant differences with respect to clinical outcome between the superior- and inferior-wall groups. Patients with poor Hunt-Hess (H-H) grades on admission showed worse outcomes than those with good H-H grades (p=0.002) and those patients without ICH revealed better outcomes than those with ICH (p=0.004).nnnCONCLUSIONSnIn patients with M1 aneurysms, clinical status on admission and the presence of ICH were significant factors for surgical outcome. Surgical morbidity seems to be related to the direction of the aneurysm. It is critical to save the lenticulostriate arteries and their branches in patients with superior-wall type aneurysms. Thorough preoperative angiographic evaluation, careful brain retraction, and meticulous inspection for hidden small branches are crucial to successful outcomes.

Angiographic Features and Clinical Outcomes of Intra-Arterial Nimodipine Injection in Patients with Subarachnoid Hemorrhage-Induced Vasospasm

Objective The aim of this study was to determine the role of intra-arterial (IA) nimodipine injections for cerebral vasospasm secondary to ruptured subarachnoid hemorrhage (SAH) and to investigate the factors that influence vasodilation and clinical outcomes. Methods We enrolled 29 patients who underwent aneurysm clipping for ruptured cerebral aneurysms between 2009 and 2011, and who received IA nimodipine after subsequently presenting with symptomatic vasospasm. The degree of vasodilation shown in angiography was measured, and the correlation between the degree of vasodilation and both the interval from SAH to cerebral vasospasm and the interval from clipping to cerebral vasospasm was determined. The change in blood flow rate after IA injection was assessed by transcranial Doppler ultrasound. Multiple clinical parameters were completed before and after IA nimodipine injection to evaluate any improvements in clinical symptoms. Results For eight patients, Glasgow Coma Scale (GCS) scores increased by two or more points. The regression analysis demonstrated a positive correlation between the change in GCS scores after IA nimodipine injection and the change in blood vessel diameter (p=0.025). A positive correlation was also observed between the interval from SAH to vasospasm and the change in diameter (p=0.040); and the interval from clipping to vasospasm and the change in diameter (p=0.022). Conclusion IA nimodipine injection for SAH-induced vasospasm led to significant vasodilation in angiography and improvement in clinical symptoms without significant complications. Our findings suggest that IA nimodipine injection should be utilized when intractable vasospasm develops despite rigorous conservative management.

Fatal Case of Cerebral Aspergillosis : A Case Report and Literature Review

Cerebral aspergillosis is rare and usually misdiagnosed because its presentation is similar to that of a tumor. The correct diagnosis is usually made intra-operatively. Cerebral abscess with fungal infection is extremely rare and few cases have been reported, but it carries a poor prognosis. A 73 year-old man presented with decreased visual acuity and paresis of the right cranial nerve III. Magnetic resonance imaging (MRI) revealed a mass in the right cavernous sinus, extened to the anterior crainial fossa and the superior orbital fissure. During surgery, a well encapsulated pus pocket was found, and histopathological examination of the mass resulted in the diagnosis of aspergillosis. Despite appropriate anti-fungal treatment, the patient eventually died from fatal cerebral ischemic change and severe brain swelling. The correct diagnosis of cerebral aspergillosis can only be achieved by histopathological examination because clinical and radiological findings including MRI are not specific. Surgical intervention and antifungal therapy should be considered the optimal treatment. Early diagnosis and aggressive antifungal treatment provide good results.

Differential clinical outcomes following encephaloduroarteriosynangiosis in pediatric moyamoya disease presenting with epilepsy or ischemia

PurposeThe purpose of this study was to compare clinical outcomes and surgical results after encephaloduroarteriosynangiosis (EDAS) in pediatric patients with Moyamoya disease that manifested as either ischemia or epileptic seizures.MethodsWe treated 23 children who underwent EDAS; we divided the patients into either ischemic or epileptic groups according to the individuals’ clinical presentation. Group Ia included those who mainly presented with cerebral ischemia in the form of preoperative transient ischemic attacks (TIA), while Group Ib presented with ischemia in the form of irreversible neurologic deficits or proven cerebral infarcts. Group II included those who presented with epileptic seizures rather than cerebral ischemia. We compared the clinical outcomes and surgical results following EDAS in the three groups.ResultsWe grouped the patients into three groups according to their main preoperative clinical symptoms (Group Ia nu2009=u200910, Group Ib nu2009=u20096, and Group II nu2009=u20097). Group II, the epileptic manifestation group, tended to show more favorable clinical outcomes compared to the ischemic manifestation group, especially the severe ischemic group. However, there were no significant differences in postoperative neuroimaging and hemodynamic assessments between the groups.ConclusionsEDAS is a safe and effective surgical technique that prevents epileptic seizures and shows more favorable clinical outcomes when used in patients with Moyamoya disease presenting with epileptic seizures compared to cerebral ischemia.

Multiple Intracranial Aneurysms with Intraventricular Hemorrhage in a Child with Unilateral Fibromuscular Dysplasia of the Renal Artery

A rare case involving multiple intracranial aneurysms with intraventricular hemorrhage (IVH) in a child, accompanied by unilateral fibromuscular dysplasia (FMD) of the renal artery, is reported. A 12-year-old girl presented with secondary hypertension and fourth-ventricle IVH. Cerebral angiography showed multiple aneurysms in the anterior communicating artery, right posterior cerebral artery, and right superior cerebellar artery. Abdominal angiography revealed marked stenosis and dilatation of the left renal artery. Coil embolization of the intracranial aneurysms was successfully performed. Then, a left nephrectomy and autotransplantation were performed. At the time of discharge, she was in an almost normal neurological condition. The association between renal artery FMD and aneurysmal rupture is extremely rare. This case is the first report of multiple intracranial aneurysms with IVH treated successfully with coils in a child concomitant with FMD of the renal artery.