C2 Vertebral Level Research Articles

Normal size of retropharyngeal lymph nodes in children on three dimensional magnetic resonance imaging.

Age-specific normal measurements or specific size criteria for retropharyngeal lymph nodes in children have not been defined. We aimed to determine the normal measurements and distribution of retropharyngeal lymph nodes on three-dimensional magnetic resonance imaging (3-D MRI) in children. In this retrospective study, we included 440 patients (213 girls) aged 0-17years who were admitted to our center with seizures and headaches and underwent brain and neck MRI with T2-sampling perfection with application-optimized contrasts using different flip angle evolution sequences. We evaluated the number, laterality, and level distribution of lateral and medial group lymph nodes according to the skull base-cervical vertebrae. For both groups, we measured the short and long diameters of the largest lymph node in the axial plane and the craniocaudal diameter in the sagittal plane. The short/long diameter ratios and volumes were determined. In 433 cases (98%), 1,554 lateral group lymph nodes were detected. Medial group lymph nodes were less common (7%). The lateral group was mostly bilateral, while the medial group was unilateral. Lateral group lymph nodes extended from the skull base-first cervical (C1) vertebral level to the C4, while the medial group extended from the C2 vertebral level to the C4. The mean axial short axis, axial long axis, and sagittal long axis diameters were 5.8mm, 10.1mm, and 15.5mm for the lateral group and 3.8mm, 7.6mm, and 10.8mm for the medial group, respectively. The findings of the study show that normally retropharyngeal lymph nodes are frequently seen in children and provide valuable information for lateral and medial lymph nodes depending on age.

Feasibility of diffusion tensor imaging in cervical spondylotic myelopathy using MUSE sequence

The most frequent type of spinal cord injury is cervical spondylotic myelopathy (CSM). Conventional structural magnetic resonance imaging (MRI) is the gold diagnosis standard for CSM. Diffusion tensor imaging (DTI) could reflect microstructural changes in the spinal cord by tracing water molecular diffusion in early stages of CSM. However, due to the complex local anatomical structure and small field of view of the spinal cord, the imaging effect of traditional DTI imaging on the spinal cord is limited. MUSE (MUltiplexed Sensitivity-Encoding) -DTI is a novel diffusion-weighted imaging (DWI) sequence that achieves higher signal intensity through multiple excitation acquisition. MUSE sequence may improve the quality of spinal cord DTI imaging. Prospective study. This study aimed to investigate the clinical diagnosis value of a novel protocol of MUSE-DTI in patients with cervical spondylotic myelopathy (CSM). From August 2021 to March 2022, a total of 60 subjects (22-71 years) were enrolled, including 51 CSM patients (22 males, 29 females) and 9 healthy subjects (4 males and 5 females). Each subject underwent a MUSE-DTI examination and a clinical Japanese Orthopedic Association (JOA) scale. We measured values of FA (Fractional Anisotropy), MD (Mean Diffusivity), AD (Axial Diffusivity), and RD (Radial Diffusivity), and collected the clinical JOA scores of each subject before the MR examination. A 3.0T MR scanner (Signa Architect, GE Healthcare) performed the MUSE-DTI sequence on each subject. The cervical canal stenosis of subjects was classified from grade 0 to grade Ⅲ according to the method of an MRI grading system. FA, MD, AD, and RD maps were generated by postprocessing MUSE-DTI data on the GE workstation. Regions of interest (ROIs) were manually drawn at the C2 vertebral body level and C2/3-C6/7 intervertebral disc levels by covering the whole spinal cord. The clinical severity of myelopathy of subjects was assessed by the clinical Japanese Orthopedic Association scale (JOA). MUSE-DTI can acquire a high-resolution diffusion image compared to traditional DTI. The FAMCL values showed a decreasing trend from grade 0 to grade Ⅲ, while the MDMCL, ADMCL, and RDMCL values showed an overall increasing trend. Significant differences in MDMCL, ADMCL, and RDMCL values were found between adjacent groups among grades Ⅰ-Ⅲ (p<.05). The ADC2 values in CSM patients (grade I-Ⅲ) were significantly lower than in healthy individuals (grade 0) (p=.019). The clinical JOA score has a significant correlation with FAMCL (p=.035), MDMCL (p<.001), ADMCL (p<.001), and RDMCL (p<.001) values. MUSE-DTI displayed a better image quality compared to traditional DTI. MUSE-DTI parameters displayed a grade-dependent trend. All the MUSE-DTI parameters at MCL were correlated with the clinical JOA scores. The ADC2 values can reflect the secondary damage of distal spinal cord. Therefore, MUSE-DTI could be a reliable biomarker for clinical auxiliary diagnosis of spinal cord injury severity in cervical spondylotic myelopathy.

Parapharyngeal Lipoma Extending to Skull Base: A Case Report with Surgical Approaches.

Parapharyngeal lipoma with skull base extension is rare tumor found in head and neck region. We report a case of 66 years old female patient with left side face swelling extending to neck. On clinical examination, it was found soft, non-tender, mobile swelling present over left side pre-auricular region. It was extending from pretragal area superiorly to left submandibular region inferiorly. CECT neck and fine needle aspiration cytology was done to know the benign nature of disease. It suggest tumor extending from skull base to C6 vertebral level in parapharyngeal space. Tumor was excised via Trans parotid-transcervical approach. Parapharyngeal lipomas are confined to either the prestyloid or post styloid compartments. We report an unusual parapharyngeal lipoma involving both the compartments of the parapharyngeal space.

Open Surgical Retrieval of a Foreign Body in the Neck: A Case Report

Foreign body retention in the neck may be either traumatic or iatrogenic. Penetrating neck injuries with retained bodies are critical, as the neck serves as a passage for structures essential to life. Therefore, prompt detection and retrieval of the foreign body are paramount in preventing mortality. Here, authors present a case in which a successful surgical retrieval was performed without any postprocedural complications, despite the patient presenting relatively late after the injury. In this case report, a 23-year-old male labourer presented with a right-sided neck swelling two months after a workplace injury involving a shattered metal plate. Imaging confirmed a 15×5 mm hyperdense metallic object penetrating the sternocleidomastoid muscle. Successful open exploration extracted a 1.5 cm metallic shard at the C6 vertebral level, with no major vessel or airway damage. Postoperatively, the patient exhibited no movement restrictions, highlighting the atypical presentation of a retained metallic foreign body and the importance of timely intervention and comprehensive imaging for successful management.

Proposed Potential Anatomical Landmarks for Percutaneous Botulinum Toxin Injection in Anterocollis-typed Cervical Dystonic Patient: A Pilot Study Utilizing Thiel-embalmed Human Cadavers

Objective: Botulinum toxin (BoTX) injection to the longus colli (LCo) muscle has been demonstrated to have a role in treating cervical dystonic (CD) patients. It can, however, cause critical complications and awareness of such complications is required. Currently, there is no substantial information regarding this novel procedure. This study aims to define the potentially safe method of injection based on assessment of anatomical measurements.Materials and Methods: We examined distances between the puncture sites and adjacent structures in Thiel-embalmed human cadavers (n=20) to propose an alternative technique for BoTX injection. Parameters were examined for the medial and lateral approaches at the fifth and sixth cervical vertebral levels. We compared each variable between the two different vertebral levels and the two different approaches to evaluate statistical differences.Results: Comparing distances between the puncture sites and neck anatomical structures in each of the two approaches, results were statistically significant. Similarly, we found using the medial approach statistical significance when comparing the measurements at the fifth with the sixth cervical vertebral level of the distances between the puncture sites and the thyroidal arteries and recurrent laryngeal nerve (p &lt; 0.05).Conclusion: The present study results provide initial guidelines for the safe technique for BoTX injection into LCo. Our findings suggest that the medial approach at the C6 vertebral level is preferable with minimal injury to vital structures. Thus, it may provide an optional method and can be used as guidance to improve surgical practice. Ethical approval was not required for this study.

Estimating the effectiveness of the multi-/interdisciplinary therapeutic program in elderly patients with incomplete myeloradicualar injuries after cervical spinal cord injury

Nowadays elderly persons may be frequent victims of traumatic cervical spinal cord injury (CSCI). A selected group of 28 (7 women (25%) and 21 (75%) men) elderly tetraplegic patients with traumatic CSCI, were admitted to the THEBA Neuromuscular Rehabilitation Clinic with incomplete (AIS-B, -C, -D) myeloradicular injuries. The female patients had an average age of 71.42 years, 5 of them coming from rural areas and 2 from urban areas. The male patients had an average age of 69.11 years, 10 of them living in rural areas, and 11 in urban areas. The spine lesi-on location was at the C2 vertebral level (in 3 women and 4 men), C3 (in a woman and 4 men), C4 (in a woman and 6 men), C5 (in 1 woman and 5 men); C6 (in a woman); C7 (for 2 men). The patients' neurological levels of injuries were: C2 (in 3 women and 4 men), C3 (in one woman and 4 men), C4 (in one woman and 6 men), C5 (in one woman and 5 men), C6 (in one woman) and C7 (in 2 men). The AIS / Frankel degree at admission, was: complete lesion (AIS-A), in 1 women patient, incomplete lesion AIS-B (in 2 male patients), AIS-C (for 2 women and 10 men), AIS-D (for 4 women and 9 men). The average muscle strength at admission was 62.71 (SD 23.32) for women patients and 59.44 (SD 26.89) for male patients; and at discharge these averages were 70.5 (SD 21.23) for women and 69.22 (SD 27.06) for men. In the study group there were 19 opera-ted patients (3 women and 16 men); in which the anterior osteosynthesis was performed (for 3 women patients and 10 male patients) and respectively the posterior vertebral approach (in 6 male patients). The neurological evolution was favorable, so that at discharge were only patients with incomplete lesions AIS-C (1 women and 11 men), AIS-D (6 women and 10 men). The follo-wing comorbidities were associated: obesity (in 2 men), arterial hypertension (in 7 women and 11 men), diabetes (in 2 women and 4 men), traumatic brain injury (in 7 men), chronic alcoholism (in 2 men), pneumonia (in one woman and 6 men), neoplastic diseases (in 2 men), osteoporosis (in one woman and one man), anemia (in one woman and one man), glaucoma (in one woman), depression (in one woman), Lyme disease (in one woman), ischemic heart disease (in 3 women and 1 man), gastric ulcer in one man and ankylosing spondylitis (in 2 men). Complications of the immobilization syndrome were enterocolitis (in 2 men), bronchopneumonia (in 6 male pati-ents), urinary tract infections (in 6 women patients and in 12 male patients) and bedsores (in one male patient). Effectiveness of the final therapeutic approach was assessed (in percentage) by evaluating the progress of the muscle strength (quantified and compared at discharge vs. admis-sion) reported to the number of days of treatment. Statistics was performed for small groups (Anova and Pearson) to establish the effectiveness of the rehabilitation program, evaluating the level of correlation between the scores quantified with the aforementioned the scales. An inver-sely proportional relationship was found between spasticity and kinetic therapy efficacy (F 0.000, Pearson -0.09), between the PENN scale scores and kinetic therapy efficacy (F 0.000, Pear-son -0.24) and a directly proportional relationship between the scores assessing quality of life, FIM and the efficacy of kinetic therapy (F 0.02, Person 0.42). These results underline the impor-tance of a multi-interdisciplinary team approach in the management of the tetraplegic patients after CSCI during the subacute post-lesional/ post-operative stage.

Effectiveness of the multi-/interdisciplinary neurorehabilitati-on program in young patients with incomplete myeloradicualar injuries after spinal cord injury

Nowadays young persons may be frequent victims of traumatic cervical spinal cord injury (CSCI). Material and methods A retrospective study (January 2019-March 2021) we conducted with the approval of the Ethics Commission of THEBA, to assess the results of the complex me-dical rehabilitation program during the subacute period. A selected group of 23 young tetraple-gic patients with traumatic CSCI, were admitted to the THEBA Neuromuscular Rehabilitation Clinic with incomplete (AIS-B, -C, -D) myeloradicular injuries. All patients were males, aged between 19 and 57 years (with a mean of 44.35 years, SD 12.9). Patients came from urban areas 11 (48%) and the remaining 12 (52%) from rural areas. Results The spine lesion location was located at C2 vertebral level (4 men), C3 (4 men), C4 (3 men), C5 (6 men); C6 (in 2 patients); C7 (in 2 men); T6 and T7 in 1 patient each. The patients' neurological levels of injury were: C1 (in 2 pati-ents), C2 (in 2 patients), C3 (in 4 patients), C5 (in 7 patients), C6 (in 4 patients) and C7 (in 2 pati-ents). The AIS/ Frankel degree at admission was: incomplete lesion AIS-B 3 patients, AIS-C 11 pa-tients, AIS-D 9 men. The average muscle strength at admission was 60.72 (SD 25.74). In the study group 20 patients were operated: anterior osteosynthesis was performed in 16 patients and pos-terior vertebral approach in 4 patients. The neurological evolution was favorable: at discharge there were only patients with incomplete AIS-C (8 men), respectively AIS-D (15 men) grade type of lesions, and their average muscle strength at discharge was 71.97 (SD 22.30). The following comorbidities were associated: arterial hypertension (in 2 patients), traumatic brain injury (in 14 patients), alcoholism (in 9 patients), pneumonia (in 6 patients), neoplastic disorders (in 1 pati-ent), gastric ulcer (in 2 patients), depression (in 2 patients). Complications of the immobilization syndrome were: enterocolitis (in 3 men), bronchopneumonia (in 3 patients), urinary tract infec-tions (in 13 patients) and bedsores (in 2 patients). Discussion Effectiveness of the final therapeutic approach was assessed (in percentage) by evaluating the progress of the muscle strength (quanti-fied and compared at discharge vs. admission) reported to the number of days of treatment. The external-internal variations of the numeric scores of the quality of life, FIM, Ashworth and Penn were evaluated. Statistics was performed for small groups (Anova and Pearson) to establish the effectiveness of the rehabilitation program, evaluating the level of correlation between the sco-res quantified with the aforementioned the scales. An inversely proportional relationship was found between spasticity and efficacy of physical therapy (F 0.000, Pearson -0.35), between the scores of Penn scale and the effectiveness of physical therapy (F test 0.000, Pearson -0.18), respec-tively directly proportional relationship between the kinetic therapy and FIM (F test 0.000, Pear-son 0.74), similar to the relationship between physical therapy and the scores assessing the quali-ty of life (F test 0.01, Pearson 0.02). Conclusions These results underline the importance of a multi-interdisciplinary team approach in the management of the tetraplegic patients after CSCI during the subacute post-lesional/ post-operative stage. Keywords: neurorehabilitation program, incomplete myeloradicualar injuries, spinal cord injury

Comparative Effectiveness of Landmark-guided Greater Occipital Nerve (GON) Block at the Superior Nuchal Line Versus Ultrasound-guided GON Block at the Level of C2: A Randomized Clinical Trial (RCT).

The purpose of this single center, prospective randomized controlled trial was to compare clinical outcomes between an ultrasound-guided greater occipital nerve block (GONB) at the C2 vertebral level versus landmark-based GONB at the superior nuchal line. Patients with occipital neuralgia or cervicogenic headache were randomized to receive either a landmark-based GONB with sham ultrasound at the superior nuchal line or ultrasound-guided GONB at the C2 vertebral level with blinding of patients and data analysis investigators. Clinical outcomes were assessed at 30 minutes, 2 weeks, and 4 weeks postinjection. Thirty-two patients were recruited with 16 participants in each group. Despite randomization, the ultrasound-guided GONB group reported higher numeric rating scale (NRS) scores at baseline. Those in the ultrasound-guided GONB group had a significant decrease in NRS from baseline compared with the landmark-based GONB group at 30 minutes (change of NRS of 4.0 vs. 2.0) and 4-week time points (change of NRS of 2.5 vs. -0.5). Both groups were found to have significant decreases in Headache Impact Test-6. The ultrasound-guided GONB had significant improvements in NRS, severe headache days, and analgesic use at 4 weeks when compared with baseline. No serious adverse events occurred in either group. Ultrasound-guided GONBs may provide superior pain reduction at 4 weeks when compared with landmark-based GONBs for patients with occipital neuralgia or cervicogenic headache.

Hirayama disease: neutral and flexion magnetic resonance imaging and utility of inter-segmental angle of flexion.

Hirayama disease (HD) is a rare disease that was commonly mis-diagnosed in the past. The importance of neutral and flexion magnetic resonance imaging (MRI) in its accurate diagnosis has been emphasized along with utility of the inter-segmental angle of flexion. Aim of the study was to observe MRI findings of HD in neutral and flexion position and measure the inter-segmental angle of flexion. Cervical MR images of 17 patients of suspected HD were evaluated retrospectively for loss of attachment (LOA) of posterior dura, lower cervical cord atrophy, T2 hyperintensity, loss of cervical lordosis, enhancement of posterior epidural venous plexus, and inter-segmental angle of flexion on neutral and flexion MRIs. Flexion MRI showed LOA of posterior dura (most commonly and maximum at C6 vertebral level) and intense enhancement in posterior epidural space in almost all patients. The mean inter-segmental angle of flexion at C5-C6 was 9.2°, and at C6-C7 it was 6°. Neutral MRI revealed LOA in 64.7%, lower cervical cord atrophy in all patients, T2 hyperintensity in the lower cervical cord in 35.2% of patients, and loss of cervical lordosis in 58.8% of patients. Flexion MRI is the gold standard for diagnosis of HD; however, certain imaging attributes, i.e. loss of attachment of posterior dura, asymmetrical lower cervical cord atrophy, T2 hyperintensity, and loss of cervical lordosis, can be seen on neutral MRI as well, which subsequently prompts the radiologist to include flexion MRI for confirmation. The inter-segmental angle of flexion is increased in patients with HD, which plays a role in planning timely surgical intervention.

Safety and Efficacy of 10 kHz Spinal Cord Stimulation for the Treatment of Refractory Chronic Migraine: A Prospective Long-Term Open-Label Study

BackgroundRefractory chronic migraine (rCM) is a highly disabling condition for which novel safe and effective treatments are needed. Safety and long-term efficacy of paresthesia-free high cervical 10 kHz spinal cord stimulation (SCS) were here prospectively evaluated for the treatment of rCM. Materials and MethodsTwenty adults with rCM (mean numbers of preventive treatments failed: 12.2 ± 3.1) were enrolled in this single-center, open-label, prospective study and implanted with a 10 kHz SCS system (Senza™ system, Nevro Corp), with the distal tip of the lead(s) positioned epidurally at the C2 vertebral level. Safety and effectiveness outcomes, such as adverse events, headache and migraine reductions, responder rates, Migraine Disability Assessment (MIDAS), Headache Impact Test-6 (HIT-6), and Migraine-Specific Quality-of-Life (MSQ), were captured up to 52 weeks after implantation. ResultsCompared to baseline, at 52 weeks postimplantation, there was a significant reduction of mean monthly migraine days (MMD) by 9.3 days (p < 0.001). Sixty percent and 50% of patients obtained respectively at least 30% and at least 50% reduction in mean MMD. By week 52, 50% of patients' chronic pattern converted to an episodic pattern. The proportion of subjects classified with severe headache-related disability on the HIT-6, decreased from 100% to 60% at week 52. Meaningful improvements of headache-related quality of life measured by the MSQ scale were observed with mean gain of 24.9 ± 23.1 (p < 0.001) points at 52 weeks. No unanticipated adverse device effects occurred. No patients required any additional device surgical revision. Conclusion10 kHz SCS may a be safe and effective neurostimulation option for rCM patients. The paresthesia-free waveform constitutes an unprecedented advantage for future methodologically sound sham-controlled studies in headache neuromodulation.

Radiological evaluation of maxillofacial soft tissue calcifications with cone beam computed tomography and panoramic radiography

We aimed to present the radiologic characteristics of maxillofacial soft tissue calcifications with a comparison of cone beam computed tomography (CBCT) and panoramic radiography (PR) findings. The study was based on CBCT images obtained for different purposes between October 2017 and September 2018. The absence, location and radiological characteristics of some calcifications were evaluated in 252 patients. Statistical analysis was performed with SPSS version 21.0; p < 0.05 was considered to indicate statistical significance. Palatine tonsilloliths were the most common calcifications in our study. Calcifications were most frequent in the sixth decade of life. Females had larger calcifications than males. There was a relationship between the sizes measured by CBCT and PR for tonsilloliths. In PR, region 2 had significantly more calcifications compared with the other regions. The C2 vertebral level was the most common region for tonsilloliths based on CBCT. Tonsilloliths have a high prevalence. The regular peripheral type had a higher risk of being a tonsillolith in PR. The peripheral/internal characteristics and the dimensions of calcifications between the two imaging modalities were in harmony. The location of calcification in PR and CBCT was important to distinguish the type of calcification.

Ultrasound tour of the anterior neck for the interventional pain physician

Ultrasound tour of the anterior neck for the interventional pain physician

Observation on Posterior Column Sensations as Predictor of Neurological Recovery in Spinal Cord Injury Patients

Objective: This study evaluated the role of preservation of posterior column in final prognosis of SCI and also compared prognostic values of posterior column and spino-thalamic tract sparing in SCI. Methodology: A prospective observational study was conducted in Department of Physical medicine and Rehabilitation in SVNIRTAR, Odisha, India from July 2017 to Dec 2018. Sample size was 55 and incomplete spinal cord injuries in ASIA B-E, neurological level C5 and below, age >10 yrs were included. Patients were classified into 2 groups of posterior column sparing and spino-thalamic sensory sparing. Patients were evaluated using ASIA scale, Neurological examination by ISNCSCI and functional improvement by SCIM III.2 groups were reassessed after 6, 9, 12 months. Results: Pure posterior column sensory sparing patients were 6 out of 55 and 50% belonged to C6 vertebral level. All 6 remained in ASIA B after 1 yr while 9 of ASIA B converted to C,10 from ASIA C to D and 1 from ASIA D to E. There were significant changes in motor and sensory scores of 2 groups which were statistically significant. SCIM score in Group A increased by 9.7 points after 1yr while there was 31.1 increase in Group B. Conclusion: Pure posterior column sensory sparing in spinal cord injury is poor prognostic indicator for neurological recovery when compared to spino-thalamic sparing patients.

High Cervical Carotid Endarterectomy–Outcome Analysis

Carotid endarterectomy (CEA) for high cervical internal carotid artery stenosis is considered to be technically demanding because of the difficulty in dissecting the distal end. We report the surgical technique and outcome analysis of CEA for high cervical lesions. We retrospectively analyzed the records of 98 patients treated by CEA from December 2013 to June 2018. The plaque positions rostral to the C2 vertebral level was defined as the high cervical lesions (n= 34). The surgical technique is to successfully expose the distal end, as follows: 1) extend the skin incision; 2) expose the great auricular nerve maximally; 3) dissect between the SCM and parotid gland fascia; 4) resect the internal deep cervical lymph nodes; and 5) retract the digastric muscle, hypoglossal nerve, and occipital artery. There were 8 cases (high cervical group, 4 cases; non-high cervical group, 4 cases) of postoperative diffusion-weighted imaging high signal and 6 cases (high cervical group, 3 cases; non-high cervical group, 3 cases) of symptomatic ischemic lesion. Four cases belonged to the technique-related cerebral infarction group and 4 cases to the perioperative-related cerebral infarction (PRCI) group. High cervical lesion is not considered to be a risk factor for either PRCI (P= 0.610) or technique-related cerebral infarction (P= 0.610). The difference of the diastolic blood pressure between the preoperative period and the second postoperative day showed a risk factor of PRCI (P= 0.033). The surgical outcomes for high cervical lesions are equivalent to that of non-high cervical lesions. Excessive blood pressure management from the early postoperative days is a risk of PRCI.

Right Vertebral Artery Spontaneous AVF Mimicking as Spinal Extradural Tumour: A Case Report

We report a case of a 20 years old female patient, who presented with the complaints of progressive quadriparesis which eventually led to quadriplegia. Her weakness started from the right side of the body and then to the left. Her MRI of the neck revealed an extradural lesion extending from the C2 up to C6 vertebral level. It had compressed the dural tube to the left. The lesion continued to the neck through the inervertebral foramen at C6. Her CT angiogram of the neck vessels showed an AVM arising from the right SCA and entering the Spinal canal at C6 level and draining into the right IJV at C2 level. She underwent surgery and the AVF was ligated at the origin. The AVM had collapsed. After 15 days following surgery, she had significant improvement of symptoms. After one and half months she could walk with support.&#x0D; Bang. J Neurosurgery 2019; 9(1): 69-74

Sympathetic blocks for complex regional pain syndrome: a survey of pain physicians

BackgroundSympathetic blocks (SB) are commonly used to treat pain from complex regional pain syndrome (CRPS). However, there are currently no guidelines to assist pain physicians in determining the best practices...

Proposal of a New Safety Margin for Placement of C2 Pedicle Screws on Computed Tomography Angiography

Screw diameters currently available are based on the literature available. No data are available for the safety margin available for C2 pedicle screw placement. The objective of this study was to define the average pedicle size available for placing C2 pedicle screws and to quantify the safety margin available in case of lateral breach of screw. Computed tomography angiograms of 259 patients (161 men, 98 women) were analyzed to calculate the C2 pedicle width, the area of the transverse foramen (TF) and the vertebral artery (VA), and the occupation ratio (OR) of the VA within the TF. The VA was classified into groups based on its lie within the TF (anteromedial, anterolateral, posteromedial, posterolateral, central, ectatic). The distance which the pedicle screw can breach without encountering the VA was calculated (lateral pedicle to vertebral artery distance [LPVA]). The diameters of the VA and the TF were estimated, and their difference gives the safety margin in case of breach of the lateral cortex of the C2 pedicle. The mean mediolateral diameter of the pedicle isthmus, perpendicular to the pedicle axis, in women was 5.3 mm and in men it was 5.8 mm. This difference was statistically significant. In 53.9% (122/226) of patients, the VA was dominant on the left side. The overall mean OR at the C2 vertebral level was found to be 37.3%. The mean LPVA was 0.9 mm, and the average overall safety margin available was 2.5 mm (range, 0.4-5.3 mm). This study describes the relationship of the VA in the C2 TF and the relative risk during pedicle screw fixation.

Accidental Hanging Leading to Spinal Cord Injury without Radiological Abnormality - A Case Report from Rural India

Spinal cord injury without radiographic abnormality (SCIWORA) is rare in adults. It is of considerable importance owing to the potential problem of management inherent in the diagnosis. We report a rare case of young female who developed quadriplegia as an outcome of accidental hanging. Her initial radiological investigation were normal but subsequent magnetic resonance imaging revealed intramedullary signal changes from C2 vertebral body level extending up to C3 level without vertebral or ligamental involvement. The patient was recuperated near completely with traditionalist treatment measures including bed rest and methylprednisolone. Routine radiographs and sometimes even computerized tomography can miss this injury and SCIWORA ought to be suspected in these instances of spinal damage giving neurological deficit.

Aortic arch origin of the left vertebral artery: An Anatomical and Radiological Study with Significance for Avoiding Complications with Anterior Approaches to the Cervical Spine.

Complications from anterior approaches to the cervical spine are uncommon with normal anatomy. However, variant anatomy might predispose one to an increased incidence of injury during such procedures. We hypothesized that left vertebral arteries that arise from the aortic arch instead of the subclavian artery might take a more medial path in their ascent making them more susceptible to iatrogenic injury. Fifty human adult cadavers were examined for left vertebral arteries having an aortic arch origin and these were dissected along their entire cervical course. Additionally, two radiological databases of CTA and arteriography procedures were retrospectively examined for cases of aberrant left vertebral artery origin from the aortic arch over a two-year period. Two cadaveric specimens (4%) were found to have a left vertebral artery arising from the aortic arch. The retrospective radiological database analysis identified 13 cases (0.87%) of left vertebral artery origin from the aortic arch. Of all cases, vertebral arteries that arose from the aortic arch were much more likely to not only have a more medial course (especially their preforaminal segment) over the cervical vertebral bodies but also to enter a transverse foramen that was more cranially located than the normal C6 entrance of the vertebral artery. Spine surgeons who approach the anterior cervical spine should be aware that an aortic origin of the left vertebral artery is likely to be closer to the midline and less protected above the C6 vertebral level. Clin. Anat. 30:811-816, 2017. © 2017Wiley Periodicals, Inc.

Navigation-Guided Endoscopic Intraventricular Injectable Tumor Model: Cadaveric Tumor Resection Model for Neurosurgical Training

Intraventricular tumors present difficult challenges to the neurosurgeon. Neurosurgeons have begun to explore the possibilities of using the endoscope in the radical resection of solid intraventricular lesions. There is a steep learning curve when dealing with such lesions with an endoscope. The aim of this study was to create a laboratory training model for neuroendoscopic surgery of intraventricular lesions guided by the navigation system. We believe this technique is more reliable than the traditional approach using contrast injection with C-arm x-ray guidance. Five formalin-fixated, latex-injected cadaveric heads were used. The arterial system was injected with red latex through the common carotid arteries, and the venous system was injected with blue latex through the internal jugular veins at the C6 vertebral level. The contrast-enhancing tumor polymer, Stratathane resin ST-504-derived polymer (SRSDP), was injected into the lateral ventricle via Frazier's point under direct endoscopic visualization and real-time neuronavigation guidance. When navigation was used for trajectory planning, the peel-away sheath was registered using a frameless navigational system (BrainLAB, Feldkirchen, Germany). A questionnaire was distributed to all participants in an endoscopic cadaveric course in which the models were used to evaluate the endoscopic tumor model. Neurosurgeons participating in the course performed an endoscopic approach to resect the intraventricular tumor model through an ipsilateral frontal burr hole. The properties of the SRSDP mixture could be manipulated through varying concentrations of the materials used, in order to reach the desired consistency of a nodular solid lesion and possibility for piecemeal resection. The tumor model allowed participants to compare between normal and pathologic endoscopic anatomy in the same cadaveric head. This injectable tumor model with the combination of neuroendoscopy and navigation can improve the accuracy of the endoscopic approach and minimize the risk of cadaveric brain specimen damage that in return augments the feeling of lifelike conditions. Using this endoscopic injectable tumor model technique can assist neurosurgeons' preparation for the challenges associated with an endoscopic piecemeal resection of a solid lesion in the lateral or third ventricle.