Spinal cord injury effectively ameliorated by neuroprotective effects of rosmarinic acid.

OBJECTIVE: Pathophysiology of spinal cord injury (SCI) causes primary and secondary effects leading to loss of neuronal function. The aim of the present study was to investigate the role of rosmarinic acid (RA) in protection against SCI. METHODS: The experimental study was carried out in male wistar rats categorized into three groups. Group I - sham operated rats; Group II - SCI; Group III - SCI followed by RA treatment (10 mg/kg). The spinal tissues after treatment schedule were analyzed for oxidative stress status through determination of reactive oxygen species (ROS), lipid peroxidation, protein damage (carbonyl and sulfhydryl contents), and antioxidant enzyme activities. The expression of oxidative stress factors NF-κB and Nrf-2 was determined by Western blot analysis. Further pro-inflammatory cytokines (TNF-α, IL-6, MCP-1, and IL-1ß) were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The results show that treatment with RA significantly enhances the antioxidant status and decrease the oxidative stress in wistar rats post-SCI. RA effectively ameliorated inflammatory mechanisms by downregulation of NF-κB and pro-inflammatory cytokines post-SCI. CONCLUSION: The study demonstrates for the first time on the role of RA in protecting the spinal cord from injury and demonstrates its neuroprotection in wistar rats.

Optimizing the Extent of Resection and Minimizing the Morbidity in Insular High-Grade Glioma Surgery by High-Field Intraoperative MRI Guidance.

AIM: The result of surgical resection for insular high-grade glioma (HGG) is disappointing due to the complex anatomy of insula and aggressive growth of HGG. The use of intraoperative magnetic resonance imaging (iMRI) was reported to improve the results of glioma surgery. The authors aimed to evaluate the impact of high-field iMRI and functional neuronavigation on the surgical resection of insular HGG. MATERIAL AND METHODS: Between July 2010 and July 2014, 51 insular HGG patients underwent operations guided by combined high-field iMRI and functional neuronavigation. Twenty-two insular HGG patients underwent conventional neuronavigation operations were assessed as the control group. Preoperative and postoperative tumor volumetric scan analysis, Karnofsky performance score (KPS) and follow-up results were reviewed retrospectively. RESULTS: Residual tumor was detected by the iMRI in 42 patients, and residual tumor of 37 patients was further resected in the iMRI-assisted group. The median extent of resection (EOR) increased significantly from 79% (58%?100%) to [96% (86%? 100%), p < 0.001]. The median EOR of iMRI-assisted group [96% (86%?100%)] was significantly higher than that of conventional neuronavigation group [84% (69%?100%); p=0.031]. Mean residual tumor volume of iMRI-assisted group [0.6 (0.0-5.2) cm3] was significantly smaller than that of conventional neuronavigation group [3.8 (0.0-12.1) cm3; p=0.003]. KPS within 3 days after surgery reduced and KPS at 3 months after surgery improved for both groups. KPS of iMRI-assisted group [90(70-100)] was significantly higher than that of control group [80(60-100); p=0.021] at 3 months after surgery. The median progression-free survival (PFS) of iMRI-assisted group [18(9-42) months] was better than that of control group [15(3-32) months; p=0.010]. The median overall survival (OS) of iMRI-assisted group [28(14-49) months] was better than that of control group [18 (7-38) months; p=0.035]. CONCLUSION: Combined high-field iMRI and functional neuronavigation optimize the extent of resection and minimize the morbidity in insular HGG surgery. Aggressive resection of insular HGG is predictive of improved OS and PFS.

Image-guided endoscopic surgery for spontaneous supratentorial intracerebral hematoma.

OBJECTIVE Endoscopic removal of intracerebral hematomas is becoming increasingly common, but there is no standard technique. The authors explored the use of a simple image-guided endoscopic method for removal of spontaneous supratentorial hematomas. METHODS Virtual reality technology based on a hospital picture archiving and communications systems (PACS) was used in 3D hematoma visualization and surgical planning. Augmented reality based on an Android smartphone app, Sina neurosurgical assist, allowed a projection of the hematoma to be seen on the patient's scalp to facilitate selection of the best trajectory to the center of the hematoma. A obturator and transparent sheath were used to establish a working channel, and an endoscope and a metal suction apparatus were used to remove the hematoma. RESULTS A total of 25 patients were included in the study, including 18 with putamen hemorrhages and 7 with lobar cerebral hemorrhages. Virtual reality combined with augmented reality helped in achieving the desired position with the obturator and sheath. The median time from the initial surgical incision to completion of closure was 50 minutes (range 40-70 minutes). The actual endoscopic operating time was 30 (range 15-50) minutes. The median blood loss was 80 (range 40-150) ml. No patient experienced postoperative rebleeding. The average hematoma evacuation rate was 97%. The mean (± SD) preoperative Glasgow Coma Scale (GCS) score was 6.7 ± 3.2; 1 week after hematoma evacuation the mean GCS score had improved to 11.9 ± 3.1 (p < 0.01). CONCLUSIONS Virtual reality using hospital PACS and augmented reality with a smartphone app helped precisely localize hematomas and plan the appropriate endoscopic approach. A transparent sheath helped establish a surgical channel, and an endoscope enabled observation of the hematoma's location to achieve satisfactory hematoma removal.

Impact of Virtual and Augmented Reality Based on Intraoperative Magnetic Resonance Imaging and Functional Neuronavigation in Glioma Surgery Involving Eloquent Areas.

BACKGROUND: The utility of virtual and augmented reality based on functional neuronavigation and intraoperative magnetic resonance imaging (MRI) for glioma surgery has not been previously investigated. METHODS: The study population consisted of 79 glioma patients and 55 control subjects. Preoperatively, the lesion and related eloquent structures were visualized by diffusion tensor tractography and blood oxygen level-dependent functional MRI. Intraoperatively, microscope-based functional neuronavigation was used to integrate the reconstructed eloquent structure and the real head and brain, which enabled safe resection of the lesion. Intraoperative MRI was used to verify brain shift during the surgical process and provided quality control during surgery. The control group underwent surgery guided by anatomic neuronavigation. RESULTS: Virtual and augmented reality protocols based on functional neuronavigation and intraoperative MRI provided useful information for performing tailored and optimized surgery. Complete resection was achieved in 55 of 79 (69.6%) glioma patients and 20 of 55 (36.4%) control subjects, with average resection rates of 95.2% ± 8.5% and 84.9% ± 15.7%, respectively. Both the complete resection rate and average extent of resection differed significantly between the 2 groups (P < 0.01). Postoperatively, the rate of preservation of neural functions (motor, visual field, and language) was lower in controls than in glioma patients at 2 weeks and 3 months (P < 0.01). CONCLUSION: Combining virtual and augmented reality based on functional neuronavigation and intraoperative MRI can facilitate resection of gliomas involving eloquent areas.

Cognitive Function After Carotid Endarterectomy: Early Decline and Later Recovery.

AIM: To prospectively study neurocognitive performance following carotid endarterectomy (CEA) in various follow-up periods, taking into account the potential confounding factors. MATERIAL AND METHODS: Thirty-six patients with carotid artery stenosis received CEA (group A). Thirty-one patients underwent surgery for femoropopliteal occlusive disease served as controls (group B). Neuropsychological testing and brain magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI) was repeated preoperatively, within 3 days and at 3 months after surgery. RESULTS: No patient had DWI evidence of procedure-related cerebral ischemia. Preoperative baseline scores of groups A and B were not statistically different in mini mental state examination (MMSE) or clock drawing task (CDT) score. MMSE and CDT scores were significantly reduced for patients in group A (p < 0.01) within 3 days after CEA. Differences of MMSE score (p=0.48) and CDT score (p=0.26) between baseline and 3 months after surgery in group A were not statistically significant. No statistically significant change of MMSE score and CDT score in group B was observed at 3 days and 3 months after the surgery. Degree of internal carotid artery (ICA) stenosis (p=0.029) and duration of ICA clamping (p=0.031) were significantly higher in patients with cognitive impairment immediately after CEA than in those without that. CONCLUSION: Our study demonstrated cognitive decline for the patients with unilateral carotid stenosis at early stage after CEA and a restorative effect at 3 months after CEA. Postoperative early cognitive impairment might be associated with intraoperative temporary hypoperfusion and postoperative hyperperfusion, not the microembolic event.

Operative Management of Intraventricular Central Neurocytomas: An Analysis of a Surgical Experience with 32 Cases.

AIM: To better understand the clinical characteristics of central neurocytoma (CN), as well as to assess the optimum therapeutic schedule. MATERIAL AND METHODS: This was a retrospective study of 32 patients with CN who visited our department between January 2008 and January 2013. We analyzed the clinical and radiological presentations, tumor characteristics, surgical strategies, and the prognosis. RESULTS: We performed operation guided by combined intraoperative magnetic resonance imaging (iMRI) and neuronavigation in 25 patients. The iMRI detected residual tumor in 9 cases, and further resection was performed in 5 cases. Total and nearly total tumor resection was achieved in 29 cases (91%). There was no significant difference between transcortical and transcallosal approaches in complications. Two cases (6%) with recurrence received respectively repeat salvage surgery and radiosurgery at 46 and 50 months after surgery. Thirty patients (94%) had excellent functional outcome (Karnofsky Performance Score ≥80) and 28 patients (88%) resumed their occupations. CONCLUSION: Our study demonstrates radical surgery with excellent neurological outcomes is the primary treatment of CN. The techniques of resection guided by combined iMRI and neuronavigation seems to enable a higher complete resection rate and reduce the morbidity rate during surgery. We suggest careful clinical observation after initial surgery, and repeat salvage surgery or radiosurgery for recurrent CN.

Multimodal treatment and management strategies for intracranial hemangiopericytoma.

Intracranial hemangiopericytoma (HPC) is a rare malignant meningothelial tumor. The authors retrospectively reviewed the long-term clinical outcomes of patients with HPC with regard to treatment modalities and histopathological grades. Eighteen women and 20 men (mean age 38.5 years, range, 18-62 years) were observed over an average follow-up period of 61 months (range, 15-133 months) between 2003 and 2013. The initial treatment modalities included total tumor resection followed by conventional radiotherapy (RT) (n=27), and subtotal tumor resection followed by stereotactic radiosurgery (n=11). One patient (3%) had permanent neurological deficits, and six patients (16%) died. Thirteen patients (34%) suffered recurrence. One year, 5 year, and 10 year recurrence-free survival rates were 100%, 70%, and 39%, respectively. Five patients (13%) developed metastasis. One year, 5 year, and 10 year metastasis-free survival rates were 100%, 89%, 74%, respectively. Low grade tumors were associated with longer overall survival, recurrence-free interval and metastasis-free interval (log-rank, p<0.05). Radical resection with RT was associated with longer overall survival and recurrence-free interval (log-rank, p<0.05), but had no effect on the metastasis-free interval (log-rank, p=0.245). Thus, radical surgery followed by adjuvant RT is the primary treatment of HPC, but recurrence and metastasis remain a common treatment outcome regardless of initial strategy. It is necessary to maintain long-term follow-up and serial imaging for all patients with intracranial HPC after treatment, regardless of extent of resection.

Posterior C1-C2 screw and rod instrument for reduction and fixation of basilar invagination with atlantoaxial dislocation.

PURPOSE: To report the surgical technique and preliminary clinical results for the treatment of basilar invagination (BI) with atlantoaxial dislocation (AAD) by posterior C1-C2 pedicle screw and rod instrument. METHODS: Between July 2012 and August 2013, 33 patients who had BI with AAD underwent surgery at our institution. Pre and postoperative three-dimensional computed tomographic (CT) scans were performed to assess the degree of dislocation. Magnetic resonance (MR) imaging was used to evaluate the compression of the medulla oblongata. For all patients, reduction of the AAD was conducted by two steps: fastening nuts and rods was performed to achieve the horizontal reduction. Distraction between C1 and C2 screws was performed to obtain the vertical reduction. RESULTS: No neurovascular injury occurred during surgery. Follow-up ranged from 6 to 15 months (mean 10.38 months) in 32 patients. Post-operative three-dimensional CT showed that complete horizontal reduction was obtained in 30/33 (90.9%), and complete vertical reduction was obtained in 31/33 (93.9%). The repeated three-dimensional CT and MR image demonstrated that bony fusion and the decompression of the medulla oblongata were obtained in all patients. Clinical symptoms improved significantly 3 months after surgery. CONCLUSIONS: This C1-C2 pedicle screw and rod instrument is a promising technique for the treatment of BI with AAD.

Operative management of trigeminal neuromas: an analysis of a surgical experience with 55 cases.

BACKGROUND: The trigeminal schwannoma is the second most common intracranial schwannoma. Their proximity to the critical skull base neural and vascular structures increases the complexity of surgical treatment. The aim of this study was to better understand the surgical approaches and the prognosis, as well as to assess the optimum therapeutic schedule. METHODS: This was a retrospective study of 55 patients with trigeminal schwannomas who visited our department between Jan 2007 and Jan 2012. We analyzed the clinical and radiological presentation, tumor characteristics, surgical approaches, the prognosis. RESULTS: The patients were 30 women and 25 men of mean age 36 years (range, 6-66 years) who received postoperative neurological and neuroradiological follow-up. The tumor was located in the middle fossa (type A) in 13 cases, in the posterior fossa (type B) in ten cases, in the middle and posterior fossae (type C) in 21 cases, and in the branches of the trigeminal nerve (type D) in 11 cases. The most common symptom was facial hypesthesia or numbness in 36 patients (65 %) . Total and nearly total tumor resection was achieved in 51 cases (93 %). Three patients (5 %) had worsening of preexisting deficits and there was no perioperative mortality. With an average follow-up period of 35 months, facial hypesthesia persisted in 26 patients (72 %),and improved in ten patients (28 %). Facial pain was relieved in 11 patients (100 %). There has been a recurrence in one case (2 %) and all patients resumed independent and social reintegration. CONCLUSION: This study demonstrates radical surgery with excellent neurological outcomes is the primary treatment of trigeminal schwannomas. Appropriate selection of surgical approach according to tumor types is highly important and necessary. The preoperative facial pain could be relieved, hypesthesia frequently remains or could even be worsened after surgery.

Operative management of brainstem hemangioblastomas.

Brainstem hemangioblastomas are technically challenging lesions. The authors retrospectively analyzed their experience in 24 patients with brainstem hemangioblastomas to evaluate the management strategies used over time and the results of microsurgical treatment. All patients were operated on between 2007 and 2012. The patients received postoperative follow-up by neuroradiological and neurological examinations. The maximum diameter of the tumors ranged from 2.0 to 4.5 cm (mean 3.6 cm). Gross total resection was achieved in 24 patients (100%). Two patients (8%) had new neurological deficits or worsening of pre-existing deficits. One patient (4%) died because of brain stem dysfunction after the operation. Radical en bloc surgical resection of brainstem hemangioblastomas in symptomatic patients is a safe and effective primary treatment. Preoperative embolization is not necessary. It is very important and necessary to differentiate and dissect precisely at the interface of the tumor surface and the brainstem with a meticulous microsurgical technique until the tumor is removed en bloc. The preoperative neurological status of the patient predicts the postoperative functional outcome. Asymptomatic patients with hemangioblastoma may be followed clinically with MRI surveillance at regular intervals.

[Individualized treatment of the atlantoaxial dislocation in craniovertebral junction abnormalities].

OBJECTIVES: To analyze the clinical characteristics of the atlantoaxial dislocation (AAD) in craniovertebral junction (CVJ) abnormalities and to study the setup of its surgery strategy. METHODS: From April 2009 to November 2011, 56 patients of AAD and CVJ abnormalities including 22 male and 34 female patients who had received surgery were analyzed. There were 2 cases of reducible AAD and 54 cases of irreducible AAD. The age of the patients ranged from 9 to 56 years (mean 34 years). Among them, 14 cases achieved reduction/partial reduction via direct posterior fixation, 41 cases had transoral anterior deconpression and occipito-cervical/C1-C2 fusion and 1 case had the posterior odontoidectomy and spinal fusion. RESULTS: Fifty-three cases had a follow-up between 6 months and 36 months (mean 20 months) and 3 cases lost follow-up (had improvement at discharge). Seven cases had complications as follows: 1 case had irreversible spinal cord injury and muscle weakness of extremities, 2 cases had cerebrospinal leak, 2 cases had pulmonary infection, 1 case had local granuloma hyperplasia and 1 case had delayed healing of the incision. The later 6 cases all got recovery after reasonable treatments. The grades of Nurick at last follow-up were as follows: 6 cases (11.3%) improved by 3 grades, 30 cases (56.6%) improved by 2 grades, 13 cases (24.5%) improved by 1 grade, 3 cases (5.7%) without change, 1 case (1.9%) get worse. CONCLUSIONS: Reducible AAD could achieve direct reduction and fixation via posterior pathways. Irreducible AAD needs individualized treatment. To choose the direct reduction and fixation or transoral odontoidectomy and posterior fixation and fusion should consider the pathogenetic condition, the image data and personal clinical experience.

[Surgical management of intracranial mirror aneurysms].

OBJECTIVE: To study the clinical characteristics and treatment strategies of mirror aneurysms. METHODS: Nineteen patients with 20 pairs of mirror aneurysms from November 2007 to November 2012 were retrospectively analysed. Among the 19 patients, 13 were female and 6 were male, mean age was 56 years (ranged 32-75 years). Distribution of the lesions included 11 bilateral posterior communicating artery aneurysms (one with a pair of anterior choroidal artery aneurysm), 4 bilateral middle cerebral artery aneurysms, 3 bilateral paraclinoidal aneurysms, and 1 bilateral pericallosal-callosomarginal artery aneurysm. Surgical strategies were selected according to location of hemorrhage, Hunt-Hess grade, location and size of aneurysm, etc. RESULTS: Four mirror aneurysms were clipped at one stage, 3 mirror aneurysms were clipped at two stages, 2 were treated with combination of clipping and coiling and remaining 10 were clipped unilaterally. At discharge, 15 out of 19 patients had a Glasgow Outcome Scale score of 5, 4 patients had a score of 4. The mean clinical follow-up was 18.6 months (range 3-50 months). Two patients had oculomotor nerve palsy postoperatively. At 3-month follow-up, 1 improved and 1 unchanged. In 10 patients with unilateral clipping, contralateral aneurysms were unruptured, small ( < 5 mm) and regular. No remnant or recurrence of aneurysm were found in other 9 patients whose bilateral aneurysms had been treated. CONCLUSIONS: The mirror aneurysms are rare kinds of multiple aneurysms. The aneurysm responsible for hemorrhage should be treated with first priority. The contralateral unruptured aneurysm could be observed, clipped or coiled in one stage, or treated in two separate stages.

[Trans-extradural approach to resect trigeminal schwannomas involving the cavernous sinus region].

OBJECTIVE: To investigate the techniques and effect of extradural approach for the resection of trigeminal schwannomas involving the cavernous sinus. METHODS: Twenty-three patients (range 26-63 years, mean age 46.2 years) with trigeminal schwannomas involving the cavernous sinus treated by middle fossa extradural approach were retrospectively analyzed. Frontotemporal orbitozygomatic extradural approach was performed in 2 patients. Frontotemporal zygomatic extradural approach was carried out in 21 patients. The first follow-up visit was on the 3rd month after surgery, and if residual was observed on enhanced MRI, then the patient was followed up every 6 months; otherwise, the patient was followed up every 8-12 months. RESULTS: The length of hospital stay after surgery was 7-13 days (mean 8.5 days). Two tumors originated from the ophthalmic branch, 2 from the maxillary branch, 5 from the mandibular branch and 14 from the gasserian ganglion. Total resection was achieved in 21 of the 23 patients (91.3%) and subtotal resection in the other 2 patients. All the patients were followed up from 3 months to 4 years. Median follow-up time was 19 months. The most common symptom was facial hypoesthesia, occurring in 18 patients. This symptom improved in 10 patients and worsened in 8 patients after surgery. New postoperative facial hypoesthesia was observed in 2 patients. Facial pain was observed in 3 patients and subsided after surgery. Two patients had loss of hearing, this symptom improved in 1 patient and worsened in 1 patient after surgery. Diplopia was observed in 6 patients. In 1 of these 6 patients, diplopia resulted from palsy of the oculomotor nerve. In the other 5 patients, diplopia resulted from palsy of the abducens nerve. This symptom improved postoperatively in all these 6 patients. New postoperative atrophy of the temporalis muscle was observed in 3 patients. There was no operation-related mortality. Tumor recurrence was only found in 1 patient after 24 months and was treated by Gamma knife. CONCLUSIONS: The middle fossa extradural approach may be an ideal option for the resection of trigeminal schwannomas involving the cavernous sinus. This approach produces no further impairment, less complication, and is less likely to injured the trigeminal nerve, abducens nerve, trochlear nerve and internal carotid artery.

Surgical management of large and giant cavernous sinus hemangiomas.

Cavernous sinus hemangiomas (CSH) are rare vascular tumors within the cavernous sinus. Gamma Knife radiosurgery (GKS) is less effective for large and giant CSH than for smaller ones. In one of the largest single-institution series reported thus far, we present 22 patients with large (3-4 cm-diameter, six patients) and giant (>4 cm, 16 patients) CSH treated surgically between 1994 and 2011. We also review related reports published since 1999 and further compare the treatment outcomes of surgery and radiosurgery. In the present study, a modified Dolenc's epidural approach was performed in 18 patients and the intradural approach was used in four. Gross total or near-total resection was achieved in 18 patients, subtotal resection was achieved in three patients and partial resection was achieved in one patient. Postoperative ophthalmoparesis occurred in seven patients (two improved, four unchanged to preoperative, one new deficit), and decreased visual acuity occurred in one patient. The reviewed literature and our experience suggest that surgical treatment of large and giant CSH is a reasonable option. A relatively low postoperative morbidity can be achieved with minimal disturbance of cranial nerve (CN) III, particularly with early localization and preservation of CN VI. GKS could be an adjunct treatment for residual tumor.

[Surgical treatment of large or giant cavernous sinus hemangiomas via epidural approach].

OBJECTIVE: To summarize the curative effect of surgically treated large or giant cavernous sinus hemangiomas (CSH) via epidural approach. METHODS: From June 1999 to June 2011, 19 cases of CSH including 15 female and 4 male patients, ranging from 26 to 70 years (mean 45.3 years) were retrospectively reviewed. Ptosis/ocular motility disorders (10 cases), headache/ophthalmalgia (7 cases), decreased visual acuity (7 cases) and facial hyperesthesia (4 cases) were the most common presenting complaints. The epidural approach was taken and the tumor dissection was performed at the interval between trochlear nerve and ophthalmic nerve and the interval between ophthalmic nerve and maxillary nerve. The curative effect was followed up regularly. RESULTS: Gross total resection was attained in 13 cases, near-total resection in 4 cases, subtotal resection in 1 case and partial resection in 1 case. The follow-up period was between 6-144 months (mean 41.5 months). The results of last follow-up were as follows: among the 10 patients with ptosis/ocular motility disorders, complete remission was achieved in 5, improvement in 2, no change in 2 and lost follow-up in 1. Facial hypoesthesia symptom got complete remission in 2 patients and partial remission in the other 2 patients. The other symptoms mentioned above were all relieved. One patient got complication with impairment of vision and ocular motility disorders. CONCLUSIONS: Combined with skilled skull base techniques, surgical treatment of large or giant CSH via epidural approach is an effective method and the preservation of cranial nerves could be attained to an acceptable level.

[Microsurgery assisted by intraoperative magnetic resonance imaging and neuronavigation for small lesions in deep brain].

OBJECTIVE: To explore the practicability of resecting small lesions in deep brain by intraoperative magnetic resonance imaging (iMRI) and neuronavigator-assisted microsurgery and its clinical efficacies. METHODS: A total of 42 cases with small lesions in deep brain underwent intraoperative MRI and neuronavigator-assisted microsurgery. The drifting of neuronavigation was corrected by images acquired from intraoperative MR rescanning. RESULTS: All lesions were successfully identified and 40 cases totally removed without mortality. Only 3 cases developed new neurological deficits post-operatively while 2 of them returned to normal neurological functions after a follow-up duration of 3 months to 2 years. CONCLUSION: The application of intraoperative MRI can effectively correct the drifting of neuronavigation and enhance the accuracy of microsurgical neuronavigation for small lesions in deep brain.

Different treatment modalities of fusiform basilar trunk aneurysm: study on computational hemodynamics.

BACKGROUND: Unclippable fusiform basilar trunk aneurysm is a formidable condition for surgical treatment. The aim of this study was to establish a computational model and to investigate the hemodynamic characteristics in a fusiform basilar trunk aneurysm. METHODS: The three-dimensional digital model of a fusiform basilar trunk aneurysm was constructed using MIMICS, ANSYS and CFX software. Different hemodynamic modalities and border conditions were assigned to the model. Thirty points were selected randomly on the wall and within the aneurysm. Wall total pressure (WTP), wall shear stress (WSS), and blood flow velocity of each point were calculated and hemodynamic status was compared between different modalities. RESULTS: The quantitative average values of the 30 points on the wall and within the aneurysm were obtained by computational calculation point by point. The velocity and WSS in modalities A and B were different from those of the remaining 5 modalities; and the WTP in modalities A, E and F were higher than those of the remaining 4 modalities. CONCLUSIONS: The digital model of a fusiform basilar artery aneurysm is feasible and reliable. This model could provide some important information to clinical treatment options.

Three-dimensional configuration and morphometric analysis of the lateral atlantoaxial articulation in congenital anomaly with occipitalization of the atlas.

STUDY DESIGN: Observational and quantitative study with 3-dimensional (3D) computerized tomographic (CT) analysis. OBJECTIVE: To establish the 3D configuration and morphometric data of obliquity of the lateral atlantoaxial articulations (LAA) in congenital anomaly with occipitalization. SUMMARY OF BACKGROUND DATA: Plane radiographs and normal CT scans cannot clearly demonstrate the configuration of LAA as the hindrance of circumambient bony structures. The morphology of anomalous LAA with occipitalization is underreported. METHODS: A series of 63 cases with occipitalization and 20 control subjects underwent thin-slice CT scanning. The 3D configuration of LAA were analyzed and categorized based on the degree of olisthy and inclination orientation of the atlantoaxial articular facets (AAF). The obliquity of the AAF was measured in reconstructed sagittal and coronal planes, respectively. RESULTS: Four types of configuration of LAA with occipitalization were found: type I, characterized by slight anteversion of LAA without olisthy of the inferior and superior facets (16% of 126 sides); type II, characterized by partial olisthy of the 2 facets and evident anteversion of LAA (48%); type III, defined by the separation or complete olisthy of the 2 facets (13%); and type IV, wherein the articular facets sloped dorsally (23%). Forty-eight of 49 cases in the former 3 types wherein AAF sloped ventrally had atlantoaxial dislocation (AAD). All type IV cases wherein AAF sloped dorsally had no AAD. In control subjects, LAA had no evident obliquity of anteversion or retroversion. CONCLUSION: Instability at the C1-C2 junction in congenital anomaly with occipitalization is likely a direct result of the anteversion of LAA and bony malformation of this region, and it aggratates with the increasing obliquity of anteversion of the AAF. Demonstrating 3D morphological changes of LAA may provide a new means to diagnosis instability in congenital anomaly at craniovertebral junction and a basis for rational surgical treatment.