Do-Sung Yoo

Surgical results in pediatric moyamoya disease: angiographic revascularization and the clinical results.

OBJECTIVE We retrospectively reviewed the pediatric patients with moyamoya disease (MMD) who underwent bypass surgery at our institution to compare the surgical results according to the surgical procedures. PATIENTS AND METHODS There were 24 total patients (age range: 2-15 years; mean age: 8.2 years). Twelve patients underwent encephalo-duro-arterio-synangiosis (EDAS) on 16 sides, 5 patients underwent encephalo-duro-arterio-myo-synangiosis (EDAMS) on 8 sides and 7 patients underwent combined superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis with EDAMS (STA-MCA-EDAMS) on 12 sides. The postoperative results were evaluated between 4 months and 5 years following surgery in terms of the angiographic revascularization and the clinical outcome. RESULTS EDAMS, regardless of the combined STA-MCA anastomosis, was significantly effective for achieving a good extent of the postoperative angiographic revascularization as compared with simple EDAS (P<0.05). STA-MCA-EDAMS tended to be better with respective to the relief of preoperative ischemic symptoms as compared with simple EDAS, although there was no significant statistical difference. CONCLUSION These results suggest that EDAMS with or without the combination of STA-MCA anastomosis was very useful for the formation of collateral circulation in comparison with simple EDAS for treating the pediatric patients with MMD, although these findings were not well correlated with the clinical outcomes.

Long-term follow-up results in 142 adult patients with moyamoya disease according to management modality

BackgroundTo clarify the most beneficial treatment of the management modality based on our experience with adult moyamoya disease (MMD).MethodsFrom 1998 to 2010, clinical results of 142 patients (ischemic, 98; hemorrhagic, 44) with adult MMD were investigated according to management modality. Revascularization surgery (direct, indirect, and combined bypass) was performed in 124 patients. We observed the clinical course of 18 patients who were treated conservatively. Clinical outcome, angiographic features, hemodynamic change, and incidence of recurrent stroke were investigated pre- and postoperatively.ResultsIn patients with ischemic MMD, direct and combined bypasses were more effective treatments to prevent recurrent ischemic stroke than indirect bypass surgery (P < 0.05). In patients with hemorrhagic MMD, rebleeding was less likely to occur in patients who had undergone bypass surgery. However, no significant difference was observed in the rebleeding rate between patients with and without revascularization surgery (P > 0.05). An angiogram after bypass surgery comparing the extent of revascularization and reduction of moyamoya vessels in patients treated with direct, indirect, and combined bypass showed a significant difference (P < 0.05) in favor of direct and combined bypass. Postoperative angiographic changes and SPECT results demonstrated significant statistical correlation (P < 0.05).ConclusionRevascularization surgery was effective in further ischemic stroke prevention to a statistically significant extent. Direct and combined bypasses were more effective to prevent recurrent ischemic stroke than indirect bypass. However, there is still no clear evidence that revascularization surgery significantly prevents rebleeding in adult MMD patients. More significant angiographic changes were observed in direct and combined bypasses compared with indirect bypass.

Embolization of intracranial aneurysms with HydroSoft coils: results of the Korean multicenter study.

BACKGROUND AND PURPOSE: Various modifications of detachable coils have been attempted to reduce recurrence rates in aneurysmal coil embolization and HydroSoft coil is one of them. The authors report their experience using HydroSoft coils in the treatment of cerebral aneurysms. MATERIALS AND METHODS: The present study is a prospective multicenter observational series of 127 aneurysms in 120 patients treated with HydroSoft coils. RESULTS: Ten centers participated in this study, and there were 92 (72%) unruptured and 35 ruptured aneurysms. Aneurysm volumes were ≥100 mm3 in 21 (17%) and <100 mm3 in 106 (83%) (mean, 56 mm3; range, 5–249 mm3). The average percentage length of HydroSoft coils detached in treated aneurysms was 67% (range, 42%–100%). Immediate postprocedural angiography demonstrated complete aneurysm occlusion in 69% (87/127 aneurysms), residual neck in 20% (25/127), and residual sac in 12% (15/127). Procedure-related adverse events occurred in 4.7% (6/127 aneurysms), including procedural bleeding (5/127) and thromboembolism (2/127), and immediate procedure-related morbidity and mortality rates were 0.8% and 0%. Conventional angiography or MRA follow-up was performed in 83% (105/127) at ≥6 months after treatment (mean interval, 11 months; range, 6–24 months). The overall recanalization rate was 3% (3/105 aneurysms; 2 major and 1 minor recanalizations). Progression to complete aneurysmal occlusion was noted in 20 of 27 aneurysms (74%) during the follow-up. CONCLUSIONS: The safety profile of HydroSoft coils appears acceptable. In terms of initial occlusion rates and durability, embolization by using HydroSoft coils seems to be favorable compared with most large series of pure platinum or coated coils.

Spinal cord injury in cervical spinal stenosis by minor trauma

BACKGROUND The size of the spinal canal is a factor that contributes to the neurologic deficits associated with cervical OPLL and CSM. We investigate the development of neurologic deterioration after minor trauma and the clinical results of decompressive surgery in cervical spinal stenosis retrospectively. METHOD We treated 200 cases (98 cervical OPLLs and 102 CSMs) of cervical spinal stenosis for 8 years. There were 63 (33.5%) minor trauma cases to the cervical spine in 200 patients. Of these 63 patients, 18 developed myelopathy, 13 showed deterioration of preexisting myelopathy, and no neurologic change was observed in 32 patients. The neurologic status was assessed by the JOA score. The patients were divided into 2 groups according to the residual cervical spinal canal diameter: group I (<10 mm cervical spinal canal) and group II (> or =10 mm cervical spinal canal). RESULTS Neurologic outcome depended on the diameter of the residual spinal canal; 22 of the 25 patients in group I developed neurologic deterioration, whereas that occurred in 8 of the 38 patients in group II (P < .05). After surgical decompression, 8 patients in group I and 30 patients in group II came out with an improved JOA score of more than 50% (P < .05). CONCLUSION Even indirect minor trauma to the neck can cause irreversible changes in the spinal cord if there is marked stenosis of the cervical spinal canal. It may be beneficial to check lateral radiograph of the cervical spine as a screening tool for early detection of cervical spinal stenosis especially in Asian people older than 40 years.

Hybrid Surgery of Multilevel Cervical Degenerative Disc Disease : Review of Literature and Clinical Results

Objective In the present study, we evaluated the effect, safety and radiological outcomes of cervical hybrid surgery (cervical disc prosthesis replacement at one level, and interbody fusion at the other level) on the multilevel cervical degenerative disc disease (DDD). Methods Fifty-one patients (mean age 46.7 years) with symptomatic multilevel cervical spondylosis were treated using hybrid surgery (HS). Clinical [neck disability index (NDI) and Visual Analogue Scale (VAS) score] and radiologic outcomes [range of motion (ROM) for cervical spine, adjacent segment and arthroplasty level] were evaluated at routine postoperative intervals of 1, 6, 12, 24 months. Review of other similar studies that examined the HS in multilevel cervical DDD was performed. Results Out of 51 patients, 41 patients received 2 level hybrid surgery and 10 patients received 3 level hybrid surgery. The NDI and VAS score were significantly decreased during the follow up periods (p<0.05). The cervical ROM was recovered at 6 and 12 month postoperatively and the mean ROM of inferior adjacent segment was significantly larger than that of superior adjacent segments after surgery. The ROM of the arthoplasty level was preserved well during the follow up periods. No surgical and device related complications were observed. Conclusion Hybrid surgery is a safe and effective alternative to fusion for the management of multilevel cervical spondylosis.

Thirteen-year Experience of 44 Patients with Adult Hemorrhagic Moyamoya Disease from a Single Institution: Clinical Analysis by Management Modality

Our objective was a retrospective assessment of the management modalities that provided the most beneficial treatment in hemorrhagic moyamoya disease during the last 13 years at our institution. The clinical results of 44 patients with hemorrhagic moyamoya disease were investigated, comparing revascularization surgery (direct, indirect, and combined bypass) or conservative treatment. Angiographic features, rebleeding, and clinical outcome were investigated. Six of the 35 patients (17.1%) with revascularization surgery experienced rebleeding, as did 4 of 9 patients (44.4%) with conservative treatment. However, patients who underwent bypass surgery had a lower chance of rebleeding. No significant difference in chance of rebleeding was observed between bypass surgery and non surgery groups (p > 0.05). Cerebral angiography performed after bypass surgery showed that for achieving good postoperative revascularization, direct and combined bypass methods were much more effective (p < 0.05). While the risk of rebleeding in the revascularization group was generally lower than in the conservative treatment group, there was no statistically significant difference between treatment modalities and conservative treatment. Although statistical significance was not attained, direct and combined bypass may reduce the risk of hemorrhage more effectively than indirect bypass.

Motor-Evoked Potential Confirmation of Functional Improvement by Transplanted Bone Marrow Mesenchymal Stem Cell in the Ischemic Rat Brain

This study investigated the effect of bone marrow mesenchymal stem cells (BMSCs) on the motor pathway in the transient ischemic rat brain that were transplanted through the carotid artery, measuring motor-evoked potential (MEP) in the four limbs muscle and the atlantooccipital membrane, which was elicited after monopolar and bipolar transcortical stimulation. After monopolar stimulation, the latency of MEP was significantly prolonged, and the amplitude was less reduced in the BMSC group in comparison with the control group (P < .05). MEPs induced by bipolar stimulation in the left forelimb could be measured in 40% of the BMSC group and the I wave that was not detected in the control group was also detected in 40% of the BMSC group. Our preliminary results imply that BMSCs transplanted to the ischemic rat brain mediate effects on the functional recovery of the cerebral motor cortex and the motor pathway.

Cranioplasty effect on the cerebral hemodynamics and cardiac function.

BACKGROUND Cranioplasty is usually performed for aesthetic, protective and patient comfort reasons. The objective of this study is to examine the effects of cranioplasty on the cerebral hemodynamics and cardiovascular system. METHODS Twenty-seven patients who had undergone cranioplasty after extensive skull bone removal to prevent uncontrollable intracranial hypertension were included in this study. Arterial blood flow velocities in the middle cerebral artery (MCA) and internal carotid artery (ICA) were assessed by transcranial doppler (TCD). The cardiac functions were evaluated using the echocardiogram. And cerebral blood flow were measured by perfusion CT. FINDINGS The blood flow velocity at the MCA ipsilateral to the cranioplasty was decreased from 50.5 +/- 15.4 cm/s preoperative to 38.1 +/- 13.9 cm/s following cranioplasty (p < 0.001) and from 33.1 +/- 8.3 cm/s to 26.4 +/- 6.6 cm/s at the ICA (p < 0.001). The stroke volume was increased from 64.7 +/- 18.3 ml/beat, to 73.3 +/- 20.4 ml/beat (p < 0.001), while the cardiac output and mean arterial blood pressure were unchanged. The cerebral blood flow was increased from 39.1 +/- 7.2 ml/100g/min to 44.7 +/- 8.9 ml/100g/min on the cranioplasty side (P = 0.05). CONCLUSIONS Cranioplasty can get rid of the atmospheric pressure on the brain and increase the cerebral blood flow as well as improve the cardiovascular functions. A skull defect should be corrected, because cranioplasty has not only aesthetic or protective effects but also improves the cardiovascular functions.

Surgical Treatment of Craniovertebral Junction Instability : Clinical Outcomes and Effectiveness in Personal Experience

OBJECTIVE Craniovertebral junction (CVJ) consists of the occipital bone that surrounds the foramen magnum, the atlas and the axis vertebrae. The mortality and morbidity is high for irreducible CVJ lesion with cervico-medullary compression. In a clinical retrospective study, the authors reviewed clinical and radiographic results of occipitocervical fusion using a various methods in 32 patients with CVJ instability. METHODS Thirty-two CVJ lesions (18 male and 14 female) were treated in our department for 12 years. Instability resulted from trauma (14 cases), rheumatoid arthritis (8 cases), assimilation of atlas (4 cases), tumor (2 cases), basilar invagination (2 cases) and miscellaneous (2 cases). Thirty-two patients were internally fixed with 7 anterior and posterior decompression with occipitocervical fusion, 15 posterior decompression and occipitocervical fusion with wire-rod, 5 C1-2 transarticular screw fixation, and 5 C1 lateral mass-C2 transpedicular screw. Outcome (mean follow-up period, 38 months) was based on clinical and radiographic review. The clinical outcome was assessed by Japanese Orthopedic Association (JOA) score. RESULTS Nine neurologically intact patients remained same after surgery. Among 23 patients with cervical myelopathy, clinical improvement was noted in 18 cases (78.3%). One patient died 2 months after the surgery because of pneumonia and sepsis. Fusion was achieved in 27 patients (93%) at last follow-up. No patient developed evidence of new, recurrent, or progressive instability. CONCLUSION The authors conclude that early occipitocervical fusion to be recommended in case of reducible CVJ lesion and the appropriate decompression and occipitocervical fusion are recommended in case of irreducible craniovertebral junction lesion.

Clinical and Radiographic Results of Unilateral Transpedicular Balloon Kyphoplasty for the Treatment of Osteoporotic Vertebral Compression Fractures

INTRODUCTION Most previous reports indicate that traditional bilateral kyphoplasty improves patient function and restores height of collapsed vertebral bodies, but limited data about the effects of unilateral kyphoplasty on clinical and radiological outcome are available. MATERIAL AND METHODS One hundred five patients were treated by unilateral kyphoplasty between January 2004 and December 2006. These patients underwent 105 operations to treat 132 vertebral compression fractures between T8 and L5. Sagittal alignment was analyzed from standing radiographs. Clinical outcomes were determined by comparison of preoperative and postoperative data from patient-reported index (visual analogue pain scale score). Radiographs were assessed as to percent vertebral collapse, vertebral height restoration and local kyphosis correction. RESULTS Mean length of follow-up was 15.3 months (range 3-36 months); improved height 2.3 and 4.0 mm in the anterior and medial columns, respectively (P > 0.05); Cobb angle increased 3.0 degrees (P < 0.05), visual analogue pain scale score improved from 8.7 +/- 1.4 before surgery to 2.3 +/- 0.9 (P < 0.05); no adverse medical or procedural complications; 6.8% (9/132) cement leakage rate. CONCLUSION Unilateral transpedicular kyphoplasty improves physical function, reduces pain, and may correct kyphotic deformity associated with vertebral compression fractures. This result shows comparable to traditional bilateral kyphoplasty procedure.