Need for head and neck repositioning to restore electrophysiological signal changes at positioning for cervical myelopathy surgery.

OBJECTIVE: To evaluate the incidence of significant intraoperative electrophysiological signal changes during surgical positioning, and to assess the effectiveness of head and neck repositioning on the restoration of signals, among patients undergoing surgery for cervical myelopathy. MATERIAL AND METHODS: We used multimodal intraoperative monitoring (somatosensory [SEP] and motor evoked potentials [MEP] and spontaneous electromyography) before and after patients' positioning in a consecutive cohort of 103 patients operated for symptomatic cervical myelopathy. Significant changes were defined as>50% attenuation in amplitude or>10% increase in latency of SEP, or abolishment or 50-80% attenuation of MEP. RESULTS: Out of 103 patients (34.9% female, median age 54.5 years) 88 underwent laminectomy (85.4%) and 15 (14.6%) anterior approach. At the time of positioning, signal alterations occurred in 44 patients (42.7%), yet only 11 patients (10.7%) showed alarming changes. Immediate neck repositioning of these resulted in complete (n=6) or partial (n=4) restoration of potentials, yielding no postoperative deficits. The patient in which signals could not be restored after repositioning resulted in added postoperative deficit. The accuracy (true positives plus true negatives) of monitoring to detect new neurological deficits was 99.0% (102/103) for the entire cohort, and 100% (11/11) for those showing significant changes at the moment of positioning. Overall, only 1 patient, with non-significant SEP attenuation, experienced a new postoperative deficit, yielding a 0.97% rate of false negatives. CONCLUSION: Among patients undergoing surgery for cervical myelopathy, 10.7% showed alarming electrophysiological signal changes at the time of positioning. Immediate repositioning of the neck resulted in near always restoration of potentials and avoidance of added neurological damage. Complete or partial restoration of potentials after repositioning yielded no postoperative deficits.

Need for head and neck repositioning to restore electrophysiological signal changes at positioning for cervical myelopathy surgery.

OBJECTIVE: To evaluate the incidence of significant intraoperative electrophysiological signal changes during surgical positioning, and to assess the effectiveness of head and neck repositioning on the restoration of signals, among patients undergoing surgery for cervical myelopathy. MATERIAL AND METHODS: We used multimodal intraoperative monitoring (somatosensory [SEP] and motor evoked potentials [MEP] and spontaneous electromyography) before and after patients' positioning in a consecutive cohort of 103 patients operated for symptomatic cervical myelopathy. Significant changes were defined as>50% attenuation in amplitude or>10% increase in latency of SEP, or abolishment or 50-80% attenuation of MEP. RESULTS: Out of 103 patients (34.9% female, median age 54.5 years) 88 underwent laminectomy (85.4%) and 15 (14.6%) anterior approach. At the time of positioning, signal alterations occurred in 44 patients (42.7%), yet only 11 patients (10.7%) showed alarming changes. Immediate neck repositioning of these resulted in complete (n=6) or partial (n=4) restoration of potentials, yielding no postoperative deficits. The patient in which signals could not be restored after repositioning resulted in added postoperative deficit. The accuracy (true positives plus true negatives) of monitoring to detect new neurological deficits was 99.0% (102/103) for the entire cohort, and 100% (11/11) for those showing significant changes at the moment of positioning. Overall, only 1 patient, with non-significant SEP attenuation, experienced a new postoperative deficit, yielding a 0.97% rate of false negatives. CONCLUSION: Among patients undergoing surgery for cervical myelopathy, 10.7% showed alarming electrophysiological signal changes at the time of positioning. Immediate repositioning of the neck resulted in near always restoration of potentials and avoidance of added neurological damage. Complete or partial restoration of potentials after repositioning yielded no postoperative deficits.

Volumetric growth rate of incidental asymptomatic meningiomas: a single-center prospective cohort study.

BACKGROUND: Decision about treatment of incidentally found intracranial meningiomas is controversial and conditioned by the growth potential of these tumors. We aimed to evaluate the growth rate of a cohort of incidentally found asymptomatic meningiomas and to analyze their natural course and the need for eventual treatment. METHODS: A total of 193 patients harboring intracranial meningiomas (85 with 109 incidental and 108 with 112 symptomatic) were included between 2015 and 2019. In the prospective cohort of incidental meningiomas, we measured size at diagnosis, volumetric growth rate (by segmentation software), appearance of symptoms, and need for surgery or radiotherapy. Progression-free survival and risk factors for growth were assessed with Kaplan-Meier survival and Cox regression analyses. RESULTS: Among incidental meningiomas, 94/109 (86.2%) remained untreated during a median follow-up of 49.3 months. Tumor growth was observed in 91 (83.5%) and > 15% growth in 40 (36.7%). Neurological symptoms developed in 1 patient (1.2%). Volume increased an average of 0.51 cm3/year (95% CI, 0.20-0.82). Nine patients were operated (9.2%) and 4 underwent radiotherapy (4.7%). Treatment-related complication rates of incidental and symptomatic meningiomas were 0% and 35.4%, respectively. Persistent neurological defects occurred in 46 (40.7%) of symptomatic versus 2 (2.3%) of incidental meningiomas. Among covariates, only brain edema resulted in an increased risk of significant tumor growth in the female subgroup (Cox regression HR 2.96, 95% CI 1.02-8.61, p = 0.046). Size at diagnosis was significantly greater in the symptomatic meningioma group (37.33 cm3 versus 4.74 cm3, p < 0.001). CONCLUSIONS: Overall, 86% of incidentally found meningiomas remained untreated over the first 4 years of follow-up. The majority grew within the 20% range, yet very few developed symptoms. Treatment-related morbidity was absent in the incidental meningioma group.

Importance of cerebral angiography and intraoperative neuromonitoring in carotid endarterectomy. / Importancia de la arteriografía cerebral y la monitorización neurofisiológica intraoperatoria en la endarterectomía carotídea.

It is an increasingly common practice to indicate a carotid endarterectomy procedure based on the information provided by non-invasive tests like Duplex ultrasound, MR angiography or CT angiography, thereby obviating the performance of a conventional cerebral angiography. We present a case of symptomatic left carotid artery 80% stenosis in which cerebral angiography showed absence of the right A1 segment and bilateral anterior cerebral artery territories that filled only from a left injection. Just 90seconds after carotid artery clamping at the neck, brain oximetry and somatosensory evoked potentials significantly dropped, that recovered after immediate clamp removal. Endarterectomy was dismissed and a carotid stent was successfully placed. This case highlights the importance of knowing the dynamics of cerebral blood circulation distal to the stenosis. If endarterectomy had been attempted, unawareness of the information provided by the cerebral angiography would have likely result in severe bi-hemispheric ischemia.

Angiographically occult and spontaneously thrombosed large brain arteriovenous malformation.

Treatment for brain arteriovenous malformations (AVM) include combinations of surgery, radiosurgery and embolization. Very rarely, spontaneous obliteration may occur, especially among small lesions with single superficial vein drainage and prior bleeding. We report the case of a large symptomatic AVM, without history of hemorrhage or prior treatment, in which self-obliteration was noted at surgery. Although MRI suggested the presence of an AVM, no evidence of arterial anomaly was observed in the brain angiography. At surgery, a large cortical nidus with tortuous arterial vessels, resembling that of an AVM but without blood flow, was identified. Complete resection was easily performed without relevant bleeding. The histopathologic study confirmed the diagnosis of a thrombosed AVM. Despite the low probability of recanalization, surgical resection of a suspected spontaneously obliterated AVM may be warranted, in order to reach a definitive diagnosis and to avoid the risk of an eventual bleeding, especially among younger patients.

Abandoned techniques in spine surgery. / Técnicas abandonadas en cirugía de columna.

In spine surgery, certain surgical techniques and devices are currently in marked decline or have been completely abandoned. Although used in thousands of patients, such treatments failed to demonstrate durable and sound effectiveness, and sometimes associate inacceptable morbidity. Chemopapain injections, percutaneous discectomy, laser discectomy or antiadhesion gels are examples of abandoned therapies. Some other techniques are in frank decline like implantation of interspinous devices or lumbar disc prosthesis. In general, a technique is abandoned due to inefficacy, excessive associated morbidity, substituted by another more efficacious and less aggressive technique, end of commercialization, or usage prohibition. In the last decades, a great commercial pressure plus an increasing social demand have managed to convince many spine surgeons to indicate treatments not sufficiently supported by scientific evidence nor consolidated over time, many of which are eventually abandoned.

Vancomycin powder for the prevention of surgical site infection in posterior elective spinal surgery. / Polvo de vancomicina tópico para la prevención de infección de herida quirúrgica en cirugía electiva de columna por vía posterior.

OBJECTIVE: To assess the effectiveness and safety of vancomycin powder as surgical site infection (SSI) prophylaxis in posterior bilateral elective spinal surgery. MATERIALS AND METHODS: Single-center quasi-experimental pre and postintervention comparative cohort study. The post-intervention group received standard intravenous antibiotic prophylaxis plus 1g of vancomycin powder into the surgical field before wound closure, and the pre-intervention group only the intravenous prophylaxis. RESULTS: 150 patients were included in each group. Twelve SSI (7 superficial and 5 deep) occurred in the post-intervention group and 16 SSI (7 superficial and 9 deep) in the pre-intervention group. The risk of deep SSI decreased from 6.0% to 3.3% (OR 0,54, 95%CI 0.17-1.65, p=0.411) with vancomycin powder. The percentage of deep SSI due to gram negative-positive germs were 80%-20% and 33%-67% for the post- and pre-intervention groups, respectively (p=0.265). No local or systemic adverse effects occurred attributable to vancomycin powder. CONCLUSION: In posterior elective spinal surgery, prophylaxis with vancomycin powder did not result in a significantly reduced incidence of superficial and deep SSI. There was a trend towards a higher incidence of deep SSI caused by gram negative microorganisms among those treated with vancomycin.

Cauda equina syndrome due to disk herniation: Long-term functional prognosis.

OBJECTIVE: Cauda equina syndrome (CES) caused by lumbar disk extrusion is classically considered an indication of urgent surgery. CES can be subdivided into CESI (incomplete CES) and CESR (complete CES with urinary retention and incontinence). This paper evaluates the long-term functional outcome of a CES cohort operated on due to disk herniation. METHODS: Single-center retrospective observational study. CES patients due to disk herniation that underwent surgery between 2000 and 2016 were included in the study. Demographic data, time intervals to diagnosis and surgery, preoperative neurologic status and outcome at the end of follow up were recorded. RESULTS: Twenty-two patients were included (median age 44 years). Eight patients were CESR and 14 CESI. Median time from symptom onset to diagnosis was 78h (range, 12-720h), and from diagnosis to surgery 24h (range, 5-120h). Median follow up was 75 months (range, 20-195 months). At the end of follow up, in the CESR group (median time from diagnosis to surgery, 23h) only pain significantly improved after surgery (p=0.007). In the CESI group (median time from diagnosis to surgery 23h) low back pain, sciatica and urinary sphincter function significantly improved (p<0.001). There were no significant differences between early (<48h) operation (n=4) and late (n=18) in terms of sphincter recovery (Fisher's Exact Test, p=0.076). CONCLUSION: Pain associated to CES improved both in the CESI and CESR groups. However, urinary sphincter impairment significantly improved only in the CESI group. No significant differences were found regarding long-term functional outcome between early and late surgery.

The appointment of an internal medicine practitioner to a neurosurgical department: Advantages, and clinical and professional implications. / Adscripción de un médico internista al servicio de neurocirugía: ventajas e implicaciones clínicas y profesionales.

The increasing age and complexity of in-hospital neurosurgery patients have raised the number of consultations with Internal Medicine. This type of collaboration is discretional and lacks temporal continuity. The full-time appointment of an internal medicine practitioner to a Neurosurgery Department, with complete care attributions except for strict surgical work, is a feasible organizational option. This method minimizes the need for medical consultation, improves the perceived quality of care, allows neurosurgeons to focus on purely surgical tasks, provides an integral vision of the patient's condition, enriches the group with specialized non-neurosurgical knowledge, and raises the scientific level of the team. In our Neurosurgery Department, an internal medicine practitioner has been working as part of the staff for 14 years. We describe her medical activity duties, the advantages our department gains from her daily work, and the professional and working implications derived.

"Prehabilitation" in degenerative spine surgery: A literature review. / «Prehabilitación¼ en cirugía de columna degenerativa: revisión de la literatura.

Surgery for lumbar degenerative pathology, although effective, results in suboptimal outcome and degrees of disability in a relevant proportion of patients. Postoperative rehabilitation has failed to demonstrate efficacy in the mid and long term. So-called "prehabilitation" (physiotherapy and/or cognitive-behavioral therapy) focuses in augmenting patients' functional capacities before surgery by improving their physical condition and their perception of pain, surgical experience or its consequences. Several studies suggest that prehabilitation improves postoperative outcome, shortens hospital stay and may reduce costs compared to classic postoperative rehabilitation. However, its true effect seems to be influenced by factors like obesity, co-morbidity and, especially, by a wrong perception of the natural history of this pathology in terms of catastrophising and kinesiphobia. In this paper we describe the concept of prehabilitation, review the literature, and discuss the role of some clinical conditionings involved.

[Radiation protection measures: Implications on the design of neurosurgery operating rooms]. / Medidas de protección radiológica: implicaciones en el diseño de quirófanos de neurocirugía.

OBJECTIVE: To describe pros and cons of some radiation protection measures and the implications on the design of a neurosurgery operating room. MATERIAL AND METHODS: Concurring with the acquisition and use of an O-arm device, a structural remodeling of our neurosurgery operating room was carried out. The theater was enlarged, the shielding was reinforced and a foldable leaded screen was installed inside the operating room. Radiation doses were measured in front of and behind the screen. RESULTS: The screen provides whole-body radiation protection for all the personnel inside the theater (effective dose <5µSv at 2,5 m from the gantry per O-arm exploration; 0,0µSv received behind the screen per O-arm exploration; and undetectable cumulative annual radiation dose behind the screen), obviates the need for leaded aprons and personal dosimeters, and minimizes the circulation of personnel. Enlarging the size of the operating room allows storing the equipment inside and minimizes the risk of collision and contamination. Rectangular rooms provide greater distance from the source of radiation. CONCLUSION: Floor, ceiling and walls shielding, a rectangular-shaped and large enough theater, the presence of a foldable leaded screen, and the security systems precluding an unexpected irruption into the operating room during irradiation are relevant issues to consider when designing a neurosurgery operating theater.

[Role of surgery in spontaneous spondylodiscitis: Experience in 83 consecutive patients]. / Papel de la cirugía en el tratamiento de las espondilodiscitis espontáneas: experiencia en 83 casos consecutivos.

OBJECTIVE: To describe and discuss the role of surgery in the management of spontaneous spondylodiscitis. PATIENTS AND METHODS: Retrospective review on the outcome and complications of a cohort of patients undergoing surgery for spontaneous (non-postoperative) spondylodiscitis of any spinal level or aetiology. RESULTS: From 1995 to 2014, 83 patients (45% females, median age 66) with spondylodiscitis were treated. Microbiological confirmation was obtained in 67.4%. Forty-four percent of patients presented with neurological defect. The most common affected level was thoracic (54.2%). The most frequent isolations were Mycobacterium tuberculosis (229%), Staphylococcus aureus (20.5%) and MRSA (7.2%). Eighty-one patients underwent surgery: simple laminectomy and/or biopsy (22.2%), debridement and posterior fixation (43.2%) and debridement and anterior fixation (34.5%). Improvement of pain or neurological defect was achieved in 86.7% of the patients; 7 patients stabilized and 2 worsened. Complications occurred in 35 patients, mainly pleural effusion (9), anaemia (7) and need for re-debridement (7). Median postoperative stay was 14days. After a median follow up of 8.5 months, 46 patients were considered completely cured, 10 presented sequelae, 22 patients were lost and 5 patients died. No readmissions occurred because of the infectious episode. CONCLUSIONS: Although prolonged and specific antibiotic therapy remains the mainstay of treatment in spontaneous spondylodiscitis, surgery provides samples for microbiological confirmation and histopathologic study, allows debridement of the infectious foci and stabilizes the spine. In our experience, the use of internal metallic fixation material accelerates recovery and does not predispose to chronic infection.

[Rationale and complications of the anterior-lateral extrapleural retroperitoneal approach for unstable thoracolumbar fractures: Experience in 86 consecutive patients]. / Fundamentos y complicaciones del abordaje anterolateral extrapleural-retroperitoneal en fracturas inestables toracolumbares: experiencia en 86 pacientes consecutivos.

OBJECTIVES: To describe the rationale, pros and cons, and complications of the anterior-lateral extrapleural retroperitoneal approach for unstable (TLICS>4) thoracolumbar fractures. PATIENTS AND METHODS: Clinical and radiological data and outcomes from a cohort treated surgically via said approach were retrospectively reviewed. All patients were operated on exclusively by 5 neurosurgeons trained in spine surgery. RESULTS: Between June 1999 and December 2015, 86 patients underwent surgery (median age 42years, most common level: L1). Approximately 32.5% presented with a preoperative neurological defect. After surgery (mean duration: 275minutes), 75.6% presented with no neurological sequelae and only one-third required blood transfusion. Median postoperative stay was 7days. Correction of kyphosis was considered adequate and suboptimal but acceptable in 91% and 9% of the patients, respectively. Complications occurred in 36 patients, the majority being transient. We observed failure of the construct in 2 cases (collapse of an expandable cage and extrusion of a locking screw). No infections, vascular or visceral lesions, permanent neurological worsening or mortality occurred during hospitalisation. One patient ultimately needed additional posterior fixation due to persistence of pain. Median follow-up was 252days (27.9% was lost to follow-up). CONCLUSIONS: The extrapleural extraperitoneal approach provides solid anterior reconstruction, allows wide decompression of the spinal canal, and permits adequate and long-lasting correction of kyphosis. The rates of infection, construct failure, need for reoperation and vascular or visceral lesions are minimal.

[Lumbar disc herniation: Natural history, role of physical examination, timing of surgery, treatment options and conflicts of interests]. / Hernia discal lumbar: historia natural, papel de la exploración, timing de la cirugía, opciones de tratamiento y conflicto de intereses.

INTRODUCTION: Indication for surgery in lumbar disc herniation (LDH) varies widely depending on the geographical area. DEVELOPMENT: A literature review is presented on the natural history, role of physical examination, timing of surgery, evidence-based treatment, and conflicts of interests in LDH. Surgery is shown to provide significant faster relief of pain compared to conservative therapy, although the effect fades after a year. There is no treatment modality better than the rest in terms of pain control and neurological recovery, nor is there a surgical technique clearly superior to simple discectomy. The lack of sound scientific evidence on the surgical indication may contribute to its great geographical variability. CONCLUSIONS: Since LDH has a favourable natural history, neuroimaging and surgery should not be considered until after a 6-week period. It is necessary to specify and respect the surgical indications for LDH, avoiding conflicts of interests.

[Total en bloc spondylectomy for spinal tumours: Technical aspects and surgical details]. / Vertebrectomía total en bloque en tumores vertebrales: consideraciones técnicas y detalles quirúrgicos.

OBJECTIVE: To describe the specific surgical details and report the lessons learned with a series of patients suffering from spinal tumours that underwent total en bloc spondylectomy (TES). METHODS: A retrospective case series review is presented, together with an analysis of the clinical and technical variables, as well as the outcomes. RESULTS: A total of 10 patients underwent TES (2000-2016) for primary (osteosarcoma, chondrosarcoma, fibrosarcoma and chordoma) and secondary spinal tumours (lung, breast, thyroid, oesophagus, and meningioma metastases). According to the Tomita classification, 2 patients had intra-compartmental tumours, and the rest presented as extra-compartmental. All patients experienced an improvement in their pain level after surgery. Nine patients preserved ambulation post-operatively and one patient developed paraplegia. Six patients needed subsequent operations for wound debridement, tumour recurrence, or revision of the fixation. Other complications included pneumothorax, pleural effusion and venous thrombosis. Four patients remain alive (4 months to 15 years follow-up). The rest died due to primary tumour progression (6.5 months to 12 years). A detailed description of the surgical steps, tips, and pitfalls is provided. Modifications of the technique and adjuncts to resection are commented on. Observation of some considerations (selection of candidates, careful blunt vertebral dissection, strict blood loss control, careful handling of the spinal cord, and maintenance of the radical resection concept at all stages) is key for a successful operative performance. CONCLUSION: TES is a paradigmatic operation, in which the concept of radical resection provides functional effectiveness and improves survival in selected patients suffering from spinal tumours. Our preliminary experience allows us to highlight some specific and relevant features, especially those favouring a simpler and safer operation.