Permanent Neurological Deterioration Research Articles

The precise midline myelotomy through anatomical posterior median septum by dissecting dorsal column in microsurgical resection of ependymoma (2-dimensional operative video).

Although resection is the gold standard treatment for spinal ependymoma, permanent neurological deterioration has been reported postoperatively in 20%-27% of patients. Despite thorough dissection of the tumor from its surroundings, conventional longitudinally directed midline myelotomy can lead to injury to the dorsal column, possibly due to deformation of the posterior median septum as the tumor grows. To address this issue, the authors have been performing precise midline myelotomy through the anatomical posterior median septum by directly dissecting the dorsal column. This video presents the principles and application of this technique.

Efficacy of combined intravenous plus intrathecal nimodipine administration in patients with severe cerebral vasospasm post‑aneurysmal subarachnoid hemorrhage: A retrospective cohort study.

Aneurysmal subarachnoid hemorrhage (aSAH) and the ensuing cerebral vasospasm (CV) and delayed cerebral ischemia (DCI) comprise the main reasons for morbidity and mortality in affected patients. The present study aimed to evaluate the efficacy of the use of combined intravenous (IV) and intrathecal (IT) nimodipine therapy for preventing permanent neurological deterioration and DCI in patients suffering from CV post-hemorrhage. The evaluation was performed using computed tomography perfusion and transcranial doppler ultrasound. The present retrospective cohort study analyzed 14 out of 146 patients diagnosed with vasospasm due to spontaneous or aSAH. These patients were divided into two groups as follows: i) The IV group, which included patients treated with only IV nimodipine; and ii) the IV + IT group, which included patients who received IV nimodipine in combination with IT nimodipine. Of the 14 patients, 7 patients were males (50%), and the mean age was 50.9 years (SD ±19 years). In total, 6 patients [42.8%; 5 (35.7%) from group A and 1 (7.1%) from group B], who experienced clinical symptoms with severe CV, were administered intra-arterial calcium channel therapy or/and IT nimodipine following the early identification of symptomatic vasospasm. The rate of adverse ischemic events was lower with IT nimodipine management during the 1 month of follow-up (6 vs. 2 events; odds ratio, 15.00; 95% confidence interval, 1.03-218.31; P=0.031). On the whole, the findings of the present study suggest that the combined use of IT nimodipine with IV admission for patients post-aSAH who developed severe CV is a safe procedure that may prevent permanent neurological deterioration and delay unfavorable ischemic incidents.

Three-column osteotomy by single-stage posterior approach in congenital and post-tubercular kyphosis: a comparison of outcomes.

To compare the clinical, radiological and functional outcomes of three-column osteotomy (3CO) by a single-stage posterior approach in patients with isolated congenital angular kyphosis (CK) and healed post-tubercular kyphosis (PTK). The hospital records of 30 patients with isolated congenital kyphosis (Group CK) and 51 patients with healed post-tubercular kyphosis (Group PTK), operated at a single centre utilizing a 3CO by a single-stage posterior-only approach, were retrospectively analysed. The two groups were compared with respect to selected demographic variables with clinical, radiological and functional outcome measures at a minimum follow-up of 24months. Patients in Group CK (median: 13years, range: 4-30years) presented earlier than those in Group PTK (median: 16years, range: 6-45years). The apex of the deformity was most often located in the thoracic spine in Group PTK, and in the thoracolumbar or lumbar spine in Group CK. The mean operative time (198.2 ± 31.5min v/s 174.4 ± 34.5; p = 0.01) and estimated blood loss (859.6 ± 312.2ml v/s 720.8 ± 187.3; p = 0.04) were significantly higher in Group PTK. While the local kyphosis angle was significantly corrected with surgery in both groups, the correction was significantly better in Group CK-this group also had significantly better overall functional (SRS-22r) scores at a follow-up of 24months (p < 0.05). The overall complication rate (29.4% v/s 23.3%) and neurological complication rate (9.8% v/s 6.6%) were higher in Group PTK. Permanent neurological deterioration occurred in one patient in each group. Patients with PTK have significantly higher age of presentation, higher operative time and higher complication rate as compared to CK. However, good functional outcomes and kyphosis angle correction can be achieved in both the groups with posterior-only three-column osteotomies.

Pushing the boundaries of accuracy and reliability during stereotactic procedures: A prospective study on 526 biopsies comparing the frameless robotic and Image-Guided Surgery systems

IntroductionA 12-year long, prospective, single center study was conducted, comparing two frameless systems for brain biopsies: ROSA robotic-assisted stereotaxy and BrainLab Varioguide image-guided stereotaxy (Image Guided Surgery, IGS). MethodAll consecutive adult and pediatric patients undergoing frameless brain biopsies were included. Successfully achieving diagnosis was the primary endpoint, analysis of all periprocedural complications was the secondary endpoint, and the tertiary endpoint was the length of the procedure, with the aim of assessing of the learning curve for each operator over time. The results for the ROSA robot and the Varioguide system were compared and benchmarked to data from the literature. ResultsWe performed 526 on 516 patients, 314 with the ROSA robot (Group A) and 212 with the IGS Varioguide (Group B). Histological diagnosis was achieved in 97.4% of cases in Group A, versus 93.3% in Group B (p < 0.05). No statistically significant difference was found for secondary and tertiary endpoints. The complication rate appeared similar between the 2 frameless systems, with a hemorrhagic complications rate of 3.5% in Group A and 4.7% in Group B. Permanent neurological deterioration was only recorded in 0.8% of cases from Group B. Mortality was recorded in 0.3% in Group A and 0.4% in Group B. ConclusionThis study provides evidence to confirm that robotic surgery lives up to its promises of increased safety, accuracy, and reliability.

Paediatric Spinal Tumours: Profile and Treatment Outcome in a Nigerian Tertiary Institution

Introduction: Paediatric spinal tumours are rare, accounting for 1–10% of all childhood central nervous system tumours. There is a paucity of information on spinal tumours in Sub-Saharan Africa. This is particularly so in the Nigerian paediatric population where neuro-oncologic data are limited. Indeed, there is no previously published work on paediatric spinal tumours in the Nigerian neurosurgical literature. The authors aim to document the profile of paediatric spinal tumours in a Nigerian tertiary institution and to contribute to the available data on paediatric central nervous system tumours in West Africa. Methods: We retrospectively evaluated data on paediatric patients who underwent surgery for spine tumours over a 20-year period at our institution. Results: A total of 12 patients were managed for paediatric spine tumours during the study period. These had a male:female ratio of 1:1.4, and their ages ranged between 3 and 18 years (mean: 12.83 ± 4.75 years). The highest incidence (6/12) was seen in the 15–18 years age group. The mean duration of symptoms was 10.2 months. More than half (7/12) of the patients presented with symptoms with duration of at least 6 months. Motor deficit was present in all patients at presentation. Two-thirds of the tumours were in the thoracic region, 1 was located in the cervical region, while the remaining 3 tumours were cervicothoracic. The tumour was extradural in location in 8 of our patients and intramedullary in the remaining 4. Astrocytoma, intramedullary in all cases, was the most predominant histological tumour type (3/12) in our series. Postoperative neurological improvement occurred in 7 of the patients while 5 remained the same. There was no permanent postoperative neurological deterioration or perioperative mortality. Conclusion: Paediatric spinal tumours mostly affected older children in our study group and were predominantly astrocytic in nature. The most common tumour location was extradural, involving mostly the thoracic spinal level. The preoperative neurological status correlates with the postoperative functional outcome. Therefore, the need for early diagnosis and treatment of these tumours cannot be overemphasized.

Clinical results of combined interlaminar and transforaminal endoscopic discectomy for central large disc herniation

ObjectiveThe purpose of this study was to inscribe the combined interlaminar with transforaminal endoscopic discectomy for central large disc herniation and report clinical results. MethodsPatients diagnosed with large central lumbar herniated nucleus pulposus who underwent combined interlaminar and transforaminal endoscopic discectomy between 2015 and 2020 were reviewed. Perioperative data, preoperative and postoperative Oswestry Disability Index (ODI) scores, visual analog scale (VAS) back pain scores, VAS leg pain scores, and complications were evaluated and recorded at 1 week and 3 and 6 months postoperatively and each year thereafter. ResultsThe study revealed 9 cases (22.22% female). The average age of patients was 42.33 ± 19.8 years old (range, 18–83 years old). The levels of surgery were L3-4 in 22.22%, L4-5 in 77.77%. This combined approach has an average operative time of 104.44 ± 22.42 min. The VAS Back and Leg were improved from pre-operative score from 5.0 ± 2.0, 4.42 ± 2.93 to 2.18 ± 1.97 and 2.55 ± 2.84 retrospectively at 1 week. The ODI score was improved pre-operative from 46.85 ± 15.61% to 14.94 ± 19.08% at 3 month follow up. There were 2 cases (22.22%) diagnosed of recurrent disc herniation. No case of epidural hematoma, infection, permanent neurological deterioration, cauda equina syndrome. ConclusionsCombined interlaminar and transforminal endoscopic discectomy is an option for central large lumbar disc herniation.

Clinical, radiological and functional outcome of posterior-only three-column osteotomy in healed, post-tubercular kyphotic deformity: a minimum of 2-year follow-up.

To describe clinical, radiological and functional outcomes of patients with post-tubercular healed kyphosis operated by posterior-only three-column osteotomy. The hospital records of 47 patients from a single center, operated for healed, post-tubercular kyphosis were retrospectively analyzed. Deformity correction in all patients was done utilizing a three-column osteotomy by a single-stage, posterior-only approach. Radiological parameters (local kyphosis angle; KA, thoracic kyphosis; TK, lumbar lordosis; LL, pelvic tilt; PT, sacral slope; SS, C7 sagittal vertical axis; C7 SVA, pelvic incidence minus lumbar lordosis; PI-LL), functional scores and clinical details of complications were recorded. The median age of the study population was 16years (6-45). The apex of deformity was in thoracic, thoracolumbar and lumbar spine in 22, 19 and 6 cases, respectively. The mean operative time was 197.2 ± 30.5min and the mean operative blood loss was 701 ± 312ml. KA (preoperative: 68.2° ± 26.9° v/s postoperative: 29.6° ± 20.3°; p value < 0.0001), C7 SVA (preoperative 20.9 ± 37.9mm v/s postoperative: 5.5 ± 16.3mm; p value = 0.005) and TK (preoperative 47.7° ± 33.2° v/s postoperative: 37.8° ± 19.8°; p value = 0.0024) underwent a significant change with surgery. Mean SRS-22r score improved after surgical correction (preoperative: 2.7 ± 0.2 v/s final follow-up: 4 ± 0.2; p < 0.0001) with the maximum improvement occurring in self-image domain. The overall complication rate was 29.7%-including 4 neurological and 10 non-neurological complications. Permanent neurological deterioration was seen in one patient. Three-column osteotomies through posterior-only approach are safe and effective and offer good clinic-radiological and function outcome in post-tubercular kyphotic deformity correction.

Safety and Efficacy of Primary Multisession Dose Fractionated Gamma Knife Radiosurgery for Jugular Paragangliomas

While multisession dose fractionated Gamma Knife radiosurgery (DFGKS) is common, its use has never been described for jugular paragangliomas (JP), which are notoriously difficult to treat. To define efficacy, safety, and complication profile of DFGKS in 2 or 3 consecutive sessions for the treatment of a cohort of 10 cases of JP. Between 2012 and 2017, 10 patients with JP were treated with DFGKS in 2 or 3 sessions, because it was not safe to treat the lesion in a single session because of the large volume or proximity to organs at risk. The small to medium-sized JP are treated with 16-22 Gy radiation, but the large-volume JP were treated with 23-25 Gy radiation dose. The Leksell G frame was kept in situ during the whole procedure. The tumor volumes on pretreatment and posttreatment imaging were compared, using the Leksell Gamma Plan treatment plan software to assess tumor progression. The patients were regularly evaluated for their clinical outcome with radiologic correlation. The mean radiologic follow-up was 39 months (range, 12-78 months). The mean marginal dose for 3 fractions and 2 fractions was 7.64 Gy at 50% and 11.2 Gy at 50%, respectively. The mean tumor size was 29.9 cm3 (range, 9.95-47.63 cm3) at treatment and 21.9 cm3 (range, 8.83-37.5 cm3) at follow-up (suggestive of 26.7% reduction). Tumor control was achieved in all patients (100%). Of 110 potential neurologic problems (signs/symptoms) evaluated (11 in each patient), 56 (50.9%) were present preoperatively. Of them, 27 (48.2%) improved and 29 (51.8%) stabilized after treatment. There were 2 new-onset neurologic problems (of 110, 1.8%) attributable to treatment (new-onset headache and spinal accessory paresis). No patient had any permanent neurologic deterioration. DFGKS for large-volume JP leads to acceptable progression-free survival, tumor control rate, and symptomatic improvement. It may be preferred to surgery or fractionated radiotherapy given its better safety, efficacy, and complication profile.

One-year efficacy and safety of the Trufill DCS Orbit and Orbit Galaxy detachable coils in the endovascular treatment of intracranial aneurysms: Results from the TRULINE study.

Background and purpose No series reported the mid-term results of Trufill DCS Orbit and Orbit Galaxy detachable coils with independent evaluation. We present the one-year safety and efficacy of these coils in real-life routine clinical practice. Methods A total of 167 patients with 167 aneurysms (39.1% ruptured) were enrolled in the prospective TRULINE study. The primary endpoint was the safety, assessed by the combined morbidity-mortality rate observed since the time of the procedure and up to one-year follow-up. For safety, primary analyses were performed on intent-to-treat population (attempted coils procedure) and all adverse events have been reviewed by an independent Data Safety Monitoring Board. For efficacy, primary analyses were performed on the per-protocol population (patients treated with more than 70% of Trufill coils and not retreated during the follow-up period) and an independent core laboratory evaluated angiographic results. Results At one-year post-procedure, neurologic impairment was observed in 6.5% (95% confidence interval: 3.5-11.8) of the patients, and 2.6% (95% confidence interval: 1.0-6.8) had a permanent neurological deterioration. Three deaths were observed, unrelated to the procedure or coils. At one year, complete occlusion was seen in 52 aneurysms (54.2%), neck remnant in 28 aneurysms (29.2%), and aneurysm remnant in 16 aneurysms (16.7%). During the one-year follow-up, the overall incidence of recurrence was 30.2% with a mean interval of 13.8 ± 4.5 months and the retreatment for major recanalization was needed in nine patients (6.3%). Conclusions The TRULINE study confirms that endovascular coiling with Trufill DCS Orbit and Orbit Galaxy detachable coils is safe and effective.

45. Rescue of the Functional Alterations of Motor Cortical Circuits in Arginase 1 Deficiency with AAV-Based Gene Therapy

The urea cycle is the main mechanism for terrestrial mammals to detoxify excess nitrogen. Disorders of the proximal urea cycle characteristically have periodic episodes of hyperammonemia leading to often severe and permanent neurological deterioration & disability. Ammonia has been implicated by compromising potassium buffering of astrocytic membranes and causing clinical neurological abnormalities by impairing cortical inhibition. Complete arginase 1 (Arg1) deficiency, a distal urea cycle disorder, is the least severe of these abnormalities, demonstrating neurological impairment including spasticity, loss of ambulation and seizures; while characterized by the presence of hyperargininemia, hyperammonemia is not a frequent clinical finding. While mortality is unfortunately common due to acute episodes of hyperammonemia in proximal urea cycle disorders, patients with hyperargininemia often are long-lived, however, suffering from progressive intellectual disability and spastic diplegia, and the mechanisms underlying the neurological dysfunction are not understood. To gain better insight on how the loss of arginase expression causes dysfunction in the developing brain, and if gene therapy could prevent these abnormalities, we studied how the excitability and functional and anatomical connectivity of motor cortical neurons are altered in the disorder using the murine knockout model. In addition, we examined if AAV expressing Arg1, administered IV on postnatal day 2, could rescue these findings. Results: Single- and double-copy loss of Arg1 caused dose-dependent decreases in intrinsic excitability, dendritic arborization complexity, and synapses in motor cortex layer V neurons. These findings show that 1) the intrinsic excitability of neurons of homozygous Arg1 knockout mice is abnormal and that, unexpectedly, heterozygous neurons (single copy loss) exhibit an intermediate phenotype compared to wild type and homozygous knockouts (double copy loss) (Fig. AFig. A); corresponding loss of Arg1 decreased the frequency of miniature excitatory postsynaptic currents and the amplitude of miniature inhibitory postsynaptic currents; 2) neuronal branching and spine phenotypes differ between genotypes with, unexpectedly, an intermediate phenotype for heterozygotes (Fig. BFig. B); and 3) with electron microscopic analysis and comparison of layer V synapses from arginase 1 knockout, heterozygous, and wild type mice, there is a very low density of excitatory (i.e. asymmetrical) synapses (Fig. CFig. C) in the knockout and decreased number of inhibitory (perisomatic) synapses (i.e. symmetrical) on somata of pyramidal cells, both dramatic findings. Finally, changes in synaptic morphology and abnormal ultrastructural features were found in knockout mice, also suggesting neuronal degeneration and inflammation. Neonatal intravenous administration on the second postnatal day with AAV expressing arginase 1 by a hepatocyte-specific promoter led to a near-resolution of these abnormalities when administered to homozygous Arg1 knockout animals. Summary: Our studies suggest that arginase 1 deficiency leads to severe and specific changes to intrinsic excitability and synaptic connectivity of motor cortical circuits. Importantly, we find that neonatal AAV-based Arg1 gene expression is effective in reversing both the physiological and anatomical hallmarks of the disorder.View Large Image | Download PowerPoint Slide

Unilateral Approach for Bilateral Microsurgical Decompression of Lumbar Spinal Stenosis: Synopsis of 15 Years of Experience with this Surgical Method

Introduction The surgical aim in the treatment of symptomatic lumbar spinal stenosis is the relief of the patient's complaints by an adequate neural decompression. In a preliminary cadaver study the unilateral laminotomy for bilateral access to the lumbar spinal canal was investigated, and the experiences were evaluated in a clinical study. Material and Methods Microsurgical decompression was performed by partial resection of the ipsilateral facet, the medial portion of the laminar arch, the contralateral facet and by complete removal of the ligamentum flavum bilaterally. Anatomical, radiological and morphometrical studies on 4 adult cadaver spine specimens have proved the feasibility of this unilateral approach. Complete bilateral flavectomy and partial bilateral facetectomy were the essential surgical steps for an adequate operative decompression. The clinical practicability in the treatment of lumbar spinal stenosis was initially confirmed in 254 patients. Results The postoperative morphometric evaluation in the cadaver study clearly demonstrates that bilateral ligamentectomy and recess decompression were adequately and successfully achieved via unilateral approach. The clinical evaluation of this technique was performed in 254 patients with symptomatic mono- or multisegmental lumbar stenosis. Postoperatively, 229 of the 254 patients with neurogenic claudication (90.2%) demonstrated a marked improvement of the walking distance. The follow-up of 249 patients (mean follow-up time was 37 months) demonstrated an excellent result without pain in 77 patients (30.9%); a good outcome with mild residual pain, but a normal working capacity in 130 patients (52.2%); and a fair outcome with unchanged postoperative low-back pain but markedly improved working capacity and walking distance in 41 patients (16.4%). There was only one patient with surgically induced, permanent neurological deterioration (0.5%). In nine patients, an inadvertent dural tear occurred, and due to unchanged symptoms three patients with a multisegmental stenosis had to be re-operated on at an additional level. During the past 15 years the author has experience with this method in over 1600 microsurgical decompression procedures. Conclusion Unilateral laminotomy and bilateral spinal canal decompression represents a safe, effective and minimally invasive surgical method and meanwhile is a routine microsurgical strategy for the treatment of patients with lumbar spinal stenosis.

もやもや病に対する血行再建術後 過灌流に対するミノサイクリンを用いた周術期管理の現状と問題点

Background: Cerebral hyperperfusion syndrome is a potential complication of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD). Prophylactic blood pressure lowering in combination with the use of minocycline, a neuroprotective antibiotic agent, has been suggested to reduce the risk of cerebral hyperperfusion. We therefore aimed to evaluate the results of this procedure in our larger series.Methods: N-isopropyl-p-[123I]iodoamphetamine single-photon emission computed tomography was performed 1 and 7 days after STA-MCA anastomosis on 89 hemispheres from 75 consecutive patients with MMD (10-66, mean 38 years old). Postoperative systolic blood pressure was strictly controlled under 130 mmHg with the intra-operative and postoperative intravenous administration of minocycline hydrochloride (200 mg/day). Then we investigated the incidence of perioperative neurological deterioration and radiological adverse events such as delayed intracranial hemorrhage.Results: All patients underwent technically successful revascularization surgeries, and none of them suffered permanent neurological deterioration postoperatively. Three patients suffered transient ischemic attack in the acute stage (3.4%), and one patient suffered delayed intracerebral hemorrhage (ICH), which caused transient aphasia (1.1%). Six patients (mean age of 51.3 years) demonstrated delayed intracranial hemorrhage (subarachnoid hemorrhage in 5, and ICH in one) (6.7%) while five of them remained asymptomatic.Conclusion: The administration of minocycline with strict blood pressure control may represent secure and effective postoperative management after STA-MCA anastomosis for MMD, while delayed intracranial hemorrhage, either symptomatic or asymptomatic, is a potential complication of this procedure.

Brainstem arteriovenous malformations: anatomical subtypes, assessment of “occlusion in situ” technique, and microsurgical results

The surgical management of brainstem arteriovenous malformations (AVMs) might benefit from the definition of anatomical subtypes and refinements of resection techniques. Many brainstem AVMs sit extrinsically on pia mater rather than intrinsically in the parenchyma, allowing treatment by occluding feeding arteries circumferentially, interrupting draining veins after arteriovenous shunting is eliminated, and leaving the obliterated nidus behind. The authors report here the largest series of brainstem AVMs to define 6 subtypes, assess this "occlusion in situ" technique, and analyze the microsurgical results. Brainstem AVMs were categorized as 1 of 6 types: anterior midbrain, posterior midbrain, anterior pontine, lateral pontine, anterior medullary, and lateral medullary AVMs. Data from a prospectively maintained AVM registry were reviewed to evaluate multidisciplinary treatment results. During a 15-year period, the authors treated 29 patients with brainstem AVMs located in the midbrain (1 anterior and 6 posterior), pons (6 anterior and 7 lateral), and medulla (1 anterior and 8 lateral). The nidus was pial in 26 cases and parenchymal in 3 cases. Twenty-three patients (79%) presented with hemorrhage. Brainstem AVMs were either resected (18 patients, 62%) or occluded in situ (11 patients, 38%). All lateral pontine AVMs were resected, and the occlusion in situ rate was highest with anterior pontine AVMs (83%). Angiography confirmed complete obliteration in 26 patients (89.6%). The surgical mortality rate was 6.9%, and the rate of permanent neurological deterioration was 13.8%. At follow-up (mean 1.3 years), good outcomes (modified Rankin Scale [mRS] score ≤ 2) were observed in 18 patients (66.7%) and poor outcomes (mRS score of 3-5) were observed in 9 patients (33.3%). The mRS scores in 21 patients (77.8%) were unchanged or improved. The best outcomes were observed with lateral pontine (100%) and lateral medullary (75%) AVMs, and the rate of worsening/death was greatest with posterior midbrain and anterior pontine AVMs (50% each). Brainstem AVMs can be differentiated by their location in the brainstem (midbrain, pons, or medulla) and the surface on which they are based (anterior, posterior, or lateral). Anatomical subtypes can help the neurosurgeon determine how to advise patients, with lateral subtypes being a favorable surgical indication along with extrinsic pial location and hemorrhagic presentation. Most AVMs are dissected with the intention to resect them, and occlusion in situ is reserved for those AVMs that do not separate cleanly from the brainstem, that penetrate into the parenchyma, or are more anterior in location, where it is difficult to visualize and preserve perforating arteries (anterior pontine and lateral medullary AVMs). Although surgical morbidity is considerable, surgery results in a better obliteration rate than nonoperative management and is indicated in highly selected patients with high rerupture risks.

320-Row Detector Dynamic 4D-CTA for the Assessment of Brain and Spinal Cord Vascular Shunting Malformations. A Technical Note.

Shunting vascular malformations of the brain and spinal cord are traditionally studied using digital subtraction angiography (DSA), the current gold standard imaging method routinely used because of its favourable combination in terms of spatial and temporal resolution. Because DSA is relatively expensive, time-consuming and carries a risk of silent embolic events and a small risk of transient or permanent neurologic deterioration, a non-invasive alternative angiographic method is of interest. New 320 row-detector CT scanners allow volumetric imaging of the whole brain with temporal resolution up to ≌ 3 Hz. Those characteristics make computed tomography angiography (CTA) an affordable imaging method to study the haemodynamics of the whole brain and can also be applied to the study of limited portions of the spinal cord. The aim of this paper is to make a brief summary of our experience in studying shunting vascular malformation of the brain and spinal cord using dynamic 4D-CTA, explaining the technical details of the studies performed at our institution, and the state-of-the-art major advantages and drawbacks of this new technique. We found that dynamic 4D-CTA is able to depict the main architectural characteristics of previously untreated vascular shunting malformations both in brain and spinal cord (i.e. their main arterial feeders and draining veins) allowing their correct diagnosis and exhaustive classification, limiting the use of DSA for therapeutic purposes.

Clinical use of diffusion tensor image-merged functional neuronavigation for brain tumor surgeries: review of preoperative, intraoperative, and postoperative data for 123 cases.

PurposeTo achieve maximal safe resection during brain tumor surgery, functional image-merged neuronavigation is widely used. We retrospectively reviewed our cases in which diffusion tensor image (DTI)-merged functional neuronavigation was performed during surgery.Materials and MethodsBetween November 2008 and May 2010, 123 patients underwent surgery utilizing DTI-merged neuronavigation. Anatomical magnetic resonance images (MRI) were obtained preoperatively and fused with DTI of major white matter tracts, such as the corticospinal tract, optic radiation, or arcuate fasciculus. We used this fused image for functional neuronavigation during brain tumor surgery of eloquent areas. We checked the DTI images together with postoperative MRI images and evaluated the integrity of white matter tracts.ResultsA single white matter tract was inspected in 78 patients, and two or more white matter tracts were checked in 45 patients. Among the 123 patients, a grossly total resection was achieved in 90 patients (73.2%), subtotal resection in 29 patients (23.6%), and partial resection in 4 patients (3.3%). Postoperative neurologic outcomes, compared with preoperative function, included the following: 100 patients (81.3%) displayed improvement of neurologic symptoms or no change, 7 patients (5.7%) experienced postoperative permanent neurologic deterioration (additional or aggravated neurologic symptoms), and 16 patients (13.0%) demonstrated transient worsening.ConclusionDTI-merged functional neuronavigation could be a useful tool in brain tumor surgery for maximal safe resection. However, there are still limitations, including white matter tract shift, during surgery and in DTI itself. Further studies should be conducted to overcome these limitations.

Safety and efficacy of osteotomy for congenital congenital scoliosis combined with split spinal cord malformation

Objective To retrospectively evaluate the safety and efficacy of osteotomy for progressive congenital scoliosis combined with split spinal cord malformation (SSCM).Methods Data of 31 patients,who had undergone osteotomy for progressive congenital scoliosis combined with SSCM from May 2008 to May 2011 in our hospital,were retrospectively analyzed.Twenty-nine patients were followed up successfully,including 11 males and 18 females,aged from 6 to 26 years (average,13 years).Seven patients had tethered cord syndrome (TCS) with progressive neurologic deterioration.Hemivertebrae resection was performed in 7 patients,pedicle subtraction osteotomy (PSO) in 16,and vertebral column resection (VCR) in 6; posterior fusion surgery was performed in all patients after the correction was obtained.Results Twenty-nine patients were followed up for 8 to 24 months (average,18 months).The coronal Cobb angle ranged from 15° to 40°(average,24.4°±18.6°) immediately after operation,with an average correction rate of 63.3％.The coronal apical vertebral translation ranged from 0 to 50 mm (average,21.1±19.2 mm) immediately after operation,with an average correction rate of 59.5％.The coronal thoracic trunk shift ranged from 0 to 28 mm (average,5.5±10.5 mm) immediately after operation,with an average correction rate of 55.0％.There were significant differences between pre-and post-operative coronal Cobb angle,coronal apical vertebral translation and coronal thoracic trunk shift.There was no permanent neurological deterioration in all patients.Pedicle screw break occurred in 4 patients,without permanent neurological compromise.Among 7 patients with TCS,muscle strength was improved in 3 patients,and urination control was improved in 1 patient.Conclusion The osteotomy for congenital scoliosis combined with SSCM is a satisfactory method,which can effectively improve the spinal deformity without significant complications.For patients with TCS,this method also can improve the restoration of neurosurgical function.However,additional large multicenter studies are necessary to further assess the safety and efficacy. Key words: Scoliosis; Spinal cord; Abnormalities; Neural tube defects; Osteotomy

Long-term neurologic outcome of hemilaminectomy and disk fenestration for treatment of dogs with thoracolumbar intervertebral disk herniation: 831 cases (2000–2007)

To determine the proportion of dogs with thoracolumbar intervertebral disk herniation (IVDH) that successfully recovered following hemilaminectomy and fenestration, the time to ambulation (TTA) in affected dogs after surgery, and the frequency of urinary and fecal incontinence in recovered dogs and to document long-term complications. Retrospective case series. 831 dogs with thoracolumbar IVDH treated by hemilaminectomy and concomitant disk fenestration by the same surgeon. For all dogs, neurologic deficits before surgery had been assessed with a modified grading system. Dogs were reexamined after surgery over a period of 3 to 6 months, and follow-up evaluation was performed at > 12 months. The proportion of dogs that neurologically improved after surgery, TTA, and incidence of fecal or urinary incontinence in recovered dogs were compared among dogs with various grades of neurologic dysfunction before surgery. Of 831 dogs, 122 had unsuccessful outcomes and 709 had successful outcomes. Of 620 dogs with intact deep nociception before surgery, 606 (97.7%) were ambulatory after surgery. Despite maintaining the ability to walk, 7 dogs were judged to have an unsuccessful outcome because the severity of ataxia did not improve. Of 211 paraplegic dogs with loss of deep nociception, 110 (52.1%) dogs became ambulatory after surgery. Long-term complications included incontinence, permanent neurologic deterioration, and self-mutilation. Dogs with paraplegia before surgery had a higher frequency of urinary or fecal incontinence, compared with dogs that were ambulatory. Prognosis for dogs with thoracolumbar IVDH that retain deep nociception in at least 1 of the pelvic limbs or tail before surgery was good.

Lessons Learned From Moyamoya Disease: Outcome of Direct/Indirect Revascularization Surgery for 150 Affected Hemispheres

Moyamoya disease is a chronic, occlusive cerebrovascular disease with unknown etiology characterized by bilateral steno-occlusive changes at the terminal portion of the internal carotid artery and an abnormal vascular network at the base of the brain. Recent advances in molecular biology and genetic research have provided better understanding of the pathophysiology of moyamoya disease, but surgical revascularization still remains the preferred treatment for this entity. The present study investigated the clinical course of 106 consecutive patients with moyamoya disease who underwent superficial temporal artery-middle cerebral artery anastomosis with indirect pial synangiosis in 150 hemispheres. The outcomes of surgery on the operated hemisphere were favorable, with no cerebrovascular event during the outpatient follow-up period (mean 58.4 months) in 89.3% (134/150). Two patients suffered hemorrhagic events on the operated hemisphere during the follow-up period (2/150, 1.33%), one of whom suffered deteriorated neurological status after hemorrhage. Despite the favorable long-term outcome, the incidence of temporary neurological deterioration due to cerebral hyperperfusion was 18.0% (27/150), but no patients suffered permanent neurological deterioration directly caused by hyperperfusion. In conclusion, direct/indirect revascularization surgery is a safe and effective treatment for moyamoya disease, although the issue of bleeding/re-bleeding remains to be solved. Postoperative cerebral hyperperfusion and peri-operative infarction are potential complications of this procedure, so we recommend intensive postoperative care and cerebral blood flow measurement in the acute stage, because the management of hyperperfusion is contradictory to that of ischemia.

Anterior surgery in selective patients with massive ossification of posterior longitudinal ligament of cervical spine: technical note

The study includes case series, technical note and review of literature. The objective of this study was to assess the validity of the radiographic indicator and the result of anterior operation for massive ossification of posterior longitudinal ligament (MOPLL, ossification of posterior longitudinal ligament with an occupying ratio exceeding 50%). Anterior decompression yielded a better outcome than posterior approach in patients with MOPLL of cervical spine. But anterior surgery has the problem of technically demanding and was associated with a high incidence of surgery-related complications. Many ways for reducing the risk of anterior surgery have been reported, including floating method, employing microscopes or burrs, and laser-assisted corpectomy. A case series of selective patients with MOPLL of cervical spine undergoing anterior surgery is reported. All patients were strictly selected based on CT images with the appearance of open-base. 29 cases with more than 12 months follow-up (average, 31.0 ± 10.0 m) were reviewed. Average age at operation was 59.3 ± 8.2 years (43-73 years). Anterior decompression was done only for one or two vertebrae. One corpectomy was done in 13 cases, two corpectomies in 3 cases, and one corpectomy and one discectomy in 13 cases. Three levels were fused in 16 cases and two levels in 13 cases. No permanent neurological deterioration was observed. Neurological improvement was observed in every patients with an average improvement rate of 64 ± 23%. Mesh migration was observed in one case. A fusion rate of 100% was achieved. Anterior surgery using our technique may be a relatively simple and safe procedure in selective patients with massive ossification of posterior longitudinal ligament of cervical spine.

Delayed hyperbaric oxygen treatment after acute carbon monoxide poisoning

Carbon monoxide (CO) is a colorless, odourless, highly toxic gas [1]. The diagnosis of CO-poisoning depends mainly on the history of exposure [2]. Carboxyhemoglobin reduces the oxygen-carrying capacity of blood, causing hypoxia [1–4]. After a period of apparent recovery, survivors of acute CO-poisoning can develop a potentially permanent neurologic deterioration (DNS) [1–3, 8]. DNS is a rare, poorly known encephalopathy with a 1–47% prevalence among CO-poisoned patients [5, 6]. Its symptoms and signs range from subtle abnormalities to severe dementia, parkinsonism, gait disturbances, mutism, and incontinence [1, 2]. Appropriate therapy for DNS is widely debated; particularly, the role of hyperbaric oxygen therapy (HBO2) is controversial. We describe a patient suffering from a striking neurologic decline after complete recovery from severe COpoisoning, who recovered after delayed HBO2 treatment. A 62 year old man was admitted to our hospital after having developed an akinetic-mute state with stereotyped movements, incontinence, gait-disturbances and cognitive deterioration over a period of 2 weeks. Twelve days before symptom’s onset, he was found unconscious in his smokefilled flat. He underwent intubation and high-flow oxygen therapy was provided. The cranial computerized tomography (TAC) which was immediately performed was normal, while after a few days it revealed symmetric hypodense globus pallidus (GP) lesions. He regained consciousness after 1 day. A week later he was asymptomatic and his neurological condition was unremarkable. Back home he returned to his normal activities. However, 12 days later he developed confusion and memory disturbances. His neurologic state began to deteriorate rapidly, progressing to akinetic mutism over the next week. He became totally unresponsive and incontinent. When he was referred to our hospital he showed a severe speechimpairment, with very poor expression and comprehension, dysarthria, and apraxia, also involving the cranial district. He was hypomimic, and he presented stereotyped movements, especially with his hands. His tone was markedly increased, standing and gait had become severely affected (Video Segment-1 of electronic supplementary material). Neuropsychological testing revealed severe dysfunction in all cognitive domains. Diffuse white matter (WM) hyperintensities, also involving the corpus callosum, were seen on T2-weighted MRI scans, accompanied by bilateral GP collapses (Fig. 1). A diagnosis of delayed encephalopathy after CO-intoxication was made. HBO2 therapy was carried out every day for 10 days at 2.5 absolute atmosphere (ATA), each session lasting 70 min, with gradual and progressive clinical improvement starting since the very first sessions of HBO2 therapy. After the treatment, the patient’s neurological state was unremarkable, with only Electronic supplementary material The online version of this article (doi:10.1007/s00415-011-5958-4) contains supplementary material, which is available to authorized users.