Beyond Classic Anastomoses Training Models: Overview of Aneurysm Creation in Rodent Vessel Model.

Nowadays, due to the decline in the number of microsurgical clippings for cerebral aneurysms and revascularization procedures, young neurosurgeons have fewer opportunities to participate and train on this type of surgery. Vascular neurosurgery is a demanding subspecialty that requires skills that can only be acquired with technical experience. This background pushes the new generations to be ready for such challenging cases by training hard on different available models, such as synthetic tubes, chicken wings, or placenta vessels. Although many training models for vascular neurosurgery have been described worldwide, one of the best is the rodent vessels model. It offers pulsation, coagulation, and real blood flow conditions in a physiologic atmosphere that mimics perfectly the intracranial human vessels environment, especially in terms of size. However, the current differences in governmental different regulations about the use of living animals in medical experimentation and the social awareness, as well as the lack of financial support, cause more difficulties for neurosurgeons to start with that kind of training. In this review, we describe the tools and techniques as basic steps for vascular microsurgery training by using rodent models, that provide an accurate copy of brain vessels environment under stable conditions. The initial three classical known microanastomoses for neurosurgeons are end-to-end, end-to-side, and side-to-side, but in literature, there have been described other more complex exercises for training and investigation, such as aneurysm models. Although there is still little data available, we aim to summarize and discuss aneurysm's training models and reviewed the current literature on the subject and its applications, including a detailed description of the techniques.

Treatment of cervical myelopathy by posterior approach: Laminoplasty vs. laminectomy with posterior fixation, are there differences from a clinical and radiological point of view?

INTRODUCTION: Cervical degenerative myelopathy is a variable and progressive degenerative disease caused by chronic compression of the spinal cord. Surgical approaches for the cervical spine can be performed anteriorly and/or posteriorly. Regarding the posterior approach, there are 2 fundamental techniques: laminoplasty and laminectomy with posterior fixation (LPF). There is still controversy concerning the technique in terms of outcome and complications. The aim of the present work is to analyze from the clinical and radiological point of view these 2 techniques: laminoplasty and LPF. MATERIALS AND METHODS: A historical cohort of 39 patients was reviewed (12 LFP and 27 laminoplasty) including patients operated in a 10 years period at the Hospital Universitario La Paz with a follow-up of 12 months after surgery was carried out. The clinical results were analyzed and compared using the Nurick scale and the modified Japanese Orthopaedic Association Scale (mJOA) and the radiological results using the Cobb angle, Sagittal Vertical Axis, T1 Slope and alignment (measured by Cobb-T1 Sloppe). RESULTS: Significant differences were observed in the postoperative improvement of the Nurick scale (p = 0.008) and mJOA (p = 0.018) in the laminoplasty group. In LFP there is a tendency to a greater improvement, but statistical significance is not reached due to the low sample size of this group. No statistically significant differences were observed in the radiological variables. Regarding the total number of complications, a higher number was observed in the laminoplasty group (7 cases) versus LFP (one case), but no statistically significant differences were observed. CONCLUSIONS: Laminoplasty and LFP are both safe and effective procedures in the treatment of cervical degenerative myelopathy. The findings of our study demonstrate statistically significant clinical improvement based on the Nurick and mJOA scales with laminoplasty. No significant differences in terms of complications or radiological variables were observed between the 2 techniques.

Case Report: Decompressive Craniectomy for COVID-19 Malignant Cerebral Artery Infarction. Is Surgery a Good Option?

SARS-CoV2 infection can lead to a prothrombotic state. Large vessel occlusion, as well as malignant cerebral stroke have been described in COVID-19 patients. In the following months, given the increase in COVID-19 cases, an increase in malignant cerebral SARS-CoV2 associated strokes are expected. The baseline situation of the patients as well as the risk of evolution to a serious disease due to the virus, depict a unique scenario. Decompressive craniectomy is a life-saving procedure indicated in patients who suffer a malignant cerebral stroke; however, it is unclear whether the same eligibility criteria should be used for patients with COVID-19. To our knowledge seven cases of decompressive craniectomy and malignant cerebral stroke have been described to date. We report on a 39-year-old female with no major risk factors for cerebrovascular disease, apart from oral contraception, and mild COVID-19 symptoms who suffered from left hemispheric syndrome. The patient underwent endovascular treatment with stenting and afterward decompressive craniectomy due to a worsening neurological status with unilateral unreactive mydriasis. We present the case and provide a comprehensive review of the available literature related to the surgical treatment for COVID-19 associated malignant strokes, to establish whether the same eligibility criteria for non-COVID-19 associated strokes should be used. Eight patients, including our case, were surgically managed due to malignant cerebral stroke. Seven of these patients received decompressive craniectomy, and six of them met the eligibility criteria of the current stroke guidelines. The mortality rate was 33%, similar to that described in non-COVID-19 cases. Two patients had a left middle cerebral artery (MCA) and both survived after decompressive craniectomy. Our results support that decompressive craniectomy, using the current stroke guidelines, should be considered an effective life-saving treatment for COVID-19-related malignant cerebral strokes.

Therapeutic approach to non-functioning pituitary adenomas. / Enfoque terapéutico de los adenomas hipofisarios no funcionantes.

The treatment of non-functioning pituitary adenomas raises two questions: when should they be treated and what role does each available treatment play. We review the usefulness of the different treatments and propose a therapeutic scheme based on the existing literature. Active treatment of pituitary adenomas should be performed when they produce symptoms, have contact with the optic tract, or have grown on imaging tests. The treatment is surgical, using radiotherapy for cases with significant non-removable postsurgical tumour remnants and for those in which histopathology studies show aggressive features. Medical treatment is reserved for situations in which surgical and radiotherapy treatments have been exhausted. The most advisable surgical treatment is endoscopic, although experienced neurosurgeons achieve results with microsurgery that are only slightly inferior.

Epidural Lipomatosis and Syringomyelia in Adulthood: Case Report and Literature Review.

BACKGROUND: We review 2 previously published cases of epidural lipomatosis associated with syringomyelia. We also present the case of a 42-year-old woman with a medullary syrinx from C1 to T3, initially only with upper limb paresthesias that presented after 10 years of follow-up for left hemiparesis and paresthesias in the tongue. Chiari malformation and cerebral or spinal space-occupying lesions were ruled out, as were other causes of syrinx except the presence of epidural lipomatosis extending from T1 to T12. CASE DESCRIPTION: Right laminotomies were performed from T1 to T12, removing excessive epidural fat tissue. After surgery the symptoms remained stable. At discharge the patient progressively recovered from the hemiparesis, and in follow-up magnetic resonance imaging the resolution of the syrinx was confirmed. CONCLUSIONS: This is the third case of a patient with a spinal syrinx and no other related causes except from spinal lipomatosis, although with only 3 cases it is not possible to completely state that lipomatosis caused the syrinx. Our case supports the trend established by the 2 previous cases. For treatment, initially patients should be managed conservatively, trying to correct the underlying etiologies of spinal lipomatosis. In case of failed conservative treatment, removal of adipose epidural excess in the most appropriate way is preferred.

Paraspinal muscle atrophy after posterior lumbar surgery with and without pedicle screw fixation with the classic technique. / Atrofia de la musculatura paraespinal después de cirugía lumbar posterior con y sin fijación transpedicular por la técnica clásica.

OBJECTIVES: Lumbar spine surgery causes a muscular injury during its approach that could worsen long-term postoperative functional results. This study aims to analyze the postoperative paraspinal atrophy associated with two types of intervention. MATERIAL AND METHODS: Clinical records and lumbar magnetic resonance imaging were collected from a group of 41 patients, 20 underwent laminectomy with lumbar fixation due to lumbar spinal stenosis (fixation group) and another group of 21 underwent hemilaminectomy without fixation due to lumbar disc disease (non-fixation group). In which muscle atrophy was analyzed quantitatively. RESULTS: We found a negative correlation between age and preoperative muscle, which was higher in those who underwent lumbar fixation (rho = -0.64 p = .002). We also found a positive correlation between preoperative muscle and postoperative atrophy (rho = 0.32 p = .041). In the age, sex and fixation adjusted multivariate linear regression model (R2 = 0.31), laminectomy with fixation is attributed to 5.3% atrophy (IC95 1.4-9.5%, p = .017); preoperative musculature > 70% is attributed to atrophy of 13.8% (95% CI 5.5%-22%, p = .002). Age did not correlate with postoperative atrophy. CONCLUSIONS: Paraspinal muscle atrophy after lumbar spinal surgery is greater if an extensive approach is performed such as complete laminectomy with bilateral facetectomy and transpedicular fixation. A greater previous musculature regardless of age, sex and type of surgery also predicts greater postoperative atrophy.

Surgical outcomes of traumatic cervical fractures in patients with ankylosing spondylitis. / Resultados quirúrgicos de fracturas cervicales traumáticas en pacientes con espondilitis anquilosante.

OBJECTIVE: Ankylosing spondylitis is an inflammatory rheumatic disease mainly affecting the axial skeleton. The rigid spine may secondarily develop osteoporosis, further increasing the risk of spinal fracture. In this study, we reviewed fractures in patients with ankylosing spondylitis that had been clinically diagnosed to better define the mechanism of injury, associated neurological deficit, predisposing factors, and management strategies. METHODS: Between January 2004 and December 2014, 6 patients with ankylosing spondylitis and neurological complications after injuries were treated. Neuroimaging evaluation was obtained in all patients by using plain radiography, CT scan, and MR imaging. The ASIA Impairment Scale was used in order to evaluate the neurologic status of the patients. Surgical decision was based on relationship of neurological involvement and spinal instability. RESULTS: A total of 6 cervical injuries were identified in a review of patients in whom ankylosing spondylitis had been diagnosed. Of these, 2 patients were associated with a hyperextension mechanism and 4 cases by flexion mechanism. Posttraumatic neurological deficits were demonstrated in all 6 cases and neurological improvement after surgery was observed in 4 of these cases. The two cases were not improved by the surgery was on a case by presenting a degree of Asia A and another patient who initially improved with surgery but died of pneumonia in the postoperative. CONCLUSIONS: Patients with ankylosing spondylitis are highly susceptible to spinal fracture and spinal cord injury even after only mild trauma. Initial CT or MR imaging of the whole spine is recommended even if the patient's symptoms are mild. The patient should also have early surgical stabilization to correct spinal deformity and avoid worsening of the patient's neurological status.

[Erythropoietin as a protective factor in rat CNS cells receiving radiotherapy -an in vitro study]. / La eritropoyetina como factor de proteccion de la radioterapia sobre celulas del sistema nervioso central. Estudio in vitro.

AIM: To investigate the effect of erythropoietin in cultured rat cerebral cortex cells receiving radiotherapy. MATERIALS AND METHODS: Cerebral cortex was taken from 17-day-old Wistar rat embryos and placed in culture. At 72 hours, the cultures were divided into two groups, one receiving 30 pM erythropoietin alpha and the other was the control group. Both groups received 6 Gy from a Phoenix apparatus and were incubated for another 24 hours before fixation in 4% formaldehyde. TUNEL technique was employed to calculate the number of apoptotic cells in the irradiated cultures. RESULTS: Apoptosis affected 25.22% of the cells cultured without erythropoietin and 15.5% in the group receiving erithropoyetin. Student's t-test was used to analyse quantitative variables and showed a significant difference in apoptosis between the two groups (p < 0.0001). CONCLUSION: Our in vitro experimental model demonstrated that erythropoietin effectively prevents apoptosis in irradiated rat SNC cells, opening new fields for investigation into protective agents for the nervous system.

TITLE: La eritropoyetina como factor de proteccion de la radioterapia sobre celulas del sistema nervioso central. Estudio in vitro.Objetivo. Investigar el efecto de la eritropoyetina en cultivos celulares de corteza cerebral de ratas cuando se administra radioterapia. Materiales y metodos. El estudio se desarrolla con la obtencion de corteza cerebral de embriones de 17 dias de preñez de ratas Wistar. Las celulas cultivadas despues de 72 horas de la extraccion de la corteza se dividieron en dos grupos, a uno de ellos se le administro eritropoyetina alfa a una concentracion de 30 pM y el otro era el grupo control. A los dos grupos de celulas se les radio con 6 Gy mediante un aparato Phoenix. Tras la radioterapia permanecieron 24 horas en la incubadora antes de fijarlas. Las celulas fueron fijadas con formaldehido al 4%. A continuacion, con la tecnica de TUNEL, se valoro el numero de celulas apoptoticas en los cultivos radiados. Resultados. Se observo un porcentaje de apoptosis del 25,22% del grupo de cultivo sin eritropoyetina, mientras que en el grupo de celulas radiadas con eritropoyetina fue del 15,5%. Las variables cuantitativas se analizaron mediante el test t de Student y el resultado de la comparacion entre los dos grupos fue estadisticamente significativo (p < 0,0001). Conclusion. En nuestro modelo experimental in vitro se comprobo que la eritropoyetina es eficaz en la prevencion de la apoptosis en celulas del sistema nervioso central de ratas por radiacion. Esto abre nuevos campos para la investigacion del efecto protector del sistema nervioso.

[Tumours of the upper cervical spine]. / Tumores vertebrales de la región cervical alta.

OBJECTIVE: Vertebral tumours arising in the upper cervical spine are rare. We present our experience in managing these neoplasms. MATERIAL AND METHODS: We retrospectively reviewed the case histories of patients treated at our institution between January 2000 and June 2011. RESULTS: There were 9 patients with tumours in C1-C2-C3: 2metastases, 3chordomas, 2plasmocytomas, 1chondrosarcoma and 1osteochondroma. All patients complained of neck pain at the time of diagnosis. Three patients underwent an anterior and posterior approach, 3 an exclusively posterior approach and 3 an exclusively anterior surgical approach. Tumour resection was intralesional in 7 cases. Chemo-radiotherapy was used as adjuvant therapy in patients with malignant tumours. CONCLUSIONS: Vertebral tumours in the upper cervical spine are usually malignant. Achieving en bloc resection is particularly challenging and is technically unfeasible in many cases. This worsens the prognosis and makes adjuvant treatment very important.