Reducing the learning curve of interlaminar full-endoscopic discectomy: mushroom model-simulation training.

PURPOSE: To describe a cheap simulation model used to reduce the learning curve of the interlaminar full-endoscopic discectomy in a pilot study. INTRODUCTION: The steep and difficult learning curve remain one of the main obstacles against the widespread diffusion of interlaminar full endoscopic lumbar discectomy (ILFED). One solution to overcome this learning curve is training with deliberate practice. As realistic models are relatively expensive and cadaver workshops not readily available, we developed a simple and cheap model to train the key steps of the procedure. METHODS: A simple and cheap model were designed. It consists of a king oyster mushroom stalk, a glove finger, a sponge and cotton wool. In order to fix the model to the table and to simulate the level of the patient's skin whereupon the hand of the surgeon relies, a wooden holding device was also used. As the purpose of this pilot study was to evaluate the model as a stimulator, it was tested during an advanced endoscopic training course. RESULTS: A step-by-step learning method with key steps was used by participants attending an advanced ILFED training on expensive realistic models. The model was considered as comparable and enough realistic to train key steps in order to reduce the learning curve and training costs. CONCLUSION: We present an affordable, simple and reproducible training model, which allows for deliberate practice of the key steps of the ILFED procedure. The model may be used by surgeons starting with spinal endoscopy.

[Spinal injury related to alpine winter sports]. / Fractures de la colonne vertébrale lors d'accidents de ski ou autres sports de neige.

Winter sports are the cause of a significant number of spinal injuries in Switzerland. However, the number of patients, the mechanism, the presentation, the diagnosis and the treatment of vertebral fractures have considerably evolved over the last decades. As the hospital of Sion, in Valais, is particularly exposed to these diagnoses, we analyzed two series of prospective cases 30 years apart (1989-1990 and 2019-2020) and propose a review of the main types and mechanisms of fractures, diagnosis, and management for the primary care physician.

Les sports d'hiver sont à l'origine d'un nombre important de lésions de la colonne vertébrale en Suisse. Cependant, le nombre de patients, le mécanisme, la présentation, le diagnostic et le traitement des fractures vertébrales ont considérablement évolué au cours des dernières décennies. L'hôpital de Sion, en Valais, étant particulièrement exposé à ces diagnostics, nous avons analysé deux séries de cas prospectives à 30 ans d'intervalle (1989-1990 et 2019-2020) et proposons une revue des principaux types et mécanismes de fractures, diagnostics, et prises en charge pour le médecin de premier recours.

[Endoscopic lumbar surgery]. / Chirurgie lombaire endoscopique.

Spinal endoscopy is the result of an evolution of techniques and technologies in the service of an ever less invasive surgery. It allows the treatment of a large range of pathologies such as disc herniation or spinal stenosis and this range continues to increase. It has already proven its non-inferiority and cost-effectiveness compared to microsurgery despite a difficult learning curve. It has the potential to replace the microscopic «gold standard¼ as it allows a faster recovery for the patient and a shorter hospital stay.

L'endoscopie spinale est le résultat d'une évolution des techniques et des technologies au service d'une chirurgie toujours moins invasive. Elle permet de traiter un bon nombre de pathologies telles que la hernie discale ou la sténose canalaire et ce nombre continue d'augmenter. Elle a déjà prouvé sa non-infériorité et son rapport coûts-bénéfices avantageux par rapport à la microchirurgie, et ce, bien que sa courbe d'apprentissage ne soit pas toujours aisée. Elle a le potentiel de remplacer le « gold standard ¼ microscopique car elle permet une récupération plus rapide pour le patient et une hospitalisation plus courte.

Intradural non-calcified thoracic disc herniation causing spontaneous intracranial hypotension: a case report.

BACKGROUND: Spontaneous intracranial hypotension (SIH) is a rare pathology caused by a cerebrospinal fluid (CSF) leak. If intractable by conventional methods (i.e. bedrest, analgesics, or epidural blood patching) it may lead to the inability of the patient to cope with daily life and eventually to life-threatening complications. Recently, calcified discogenic microspurs or dorsal osteophytes were identified as a major cause for ventral CSF loss through vertical longitudinal dural slits. We report a rare case of intractable SIH due to an intradural disc herniation at the thoracolumbar junction (without signs of calcification) and its management. CASE PRESENTATION: A 46-year old woman suffered from orthostatic headache (sudden onset, no history of trauma) due to intractable SIH for over 2 month (without neurologic deficits). There was no clinical amelioration by conservative measures (analgesics, bedrest) and serial unspecific epidural blood patches (repeated for 3 times). She was diagnosed with an intradural disc herniation at the thoracolumbar junction causing a CSF leak. Surgical exploration by a translaminar and transdural approach with removal of the disc herniation and closure of the CSF leak was performed with immediate cessation of orthostatic symptoms. Histological workup revealed non-calcified intervertebral disc material. After 3 months of follow-up and no evidence for clinical relapse the patient returned to work. CONCLUSIONS: We report the rare phenomenon of an intradural non-calcified disc sequester at the thoracolumbar junction as the cause of a ventral dural tear leading to a CSF leak with intractable SIH. This is of particular interest as the major cause of ventral dural leakage is thought to arise from calcified discogenic microspurs or dorsal osteophytes. Furthermore, we comprehensively describe a short and reasonable diagnostic and surgical approach of this rare pathology, which may particularly be of use in daily clinical routine in neurological wards and general surgical spine centers not facing such pathologies on a regular basis.

Neurodegenerative cerebrospinal fluid biomarkers tau and amyloid beta predict functional, quality of life, and neuropsychological outcomes after aneurysmal subarachnoid hemorrhage.

Cerebrospinal fluid (CSF) biomarkers might be useful in predicting outcome after aneurysmal subarachnoid hemorrhage (aSAH). It was the aim to determine whether tau and amyloid beta CSF concentrations predict functional, health-related quality of life (hrQoL), and neuropsychological outcomes after aSAH. Ventricular CSF was obtained from n = 24 aSAH patients at admission (D0), day 2 (D2), and day 6 (D6). CSF total (t)Tau, phosphorylated (p)Tau(181P), and amyloid beta(1-40 and 1-42) (Aß40/Aß42) levels were compared between patients with favorable and unfavorable functional (modified Rankin Scale (mRS)), hrQoL (Euro-Qol (EQ-5D)), and neuropsychological outcomes at 3 (3 m) and 12 months (12 m). Patients with unfavorable functional (mRS 4-6) and hrQoL outcome (EQ-5D z-score ≤ - 1.0) at 3 and 12 m had higher CSF tTau/pTau and lower Aß40/Aß42 at D0, D2, and D6 with varying degrees of statistical significance. In terms of predicting neuropsychological outcome, CSF pTau showed a statistically significant correlation with the z-scores of executive function (r = - 0.7486, p = 0.008), verbal memory (r = - 0.8101, p = 0.002), attention (r = - 0.6498, p = 0.030), and visuospatial functioning (r = - 0.6944, p = 0.017) at 3 m. At 12 m, CSF pTau had statistically significant correlations with the z-scores of verbal memory (r = - 0.7473, p = 0.008) and visuospatial functioning (r = - 0.6678, p = 0.024). In conclusion, higher tTau/pTau and lower Aß40/Aß42 CSF levels predict unfavorable long-term functional and hrQoL outcomes. Neuropsychological deficits correlate with increased CSF tTau and pTau concentrations.

Vertebrobasilar dolichoectasia causing homonymous hemianopia: a case report and review of the literature.

A 73-year-old man was diagnosed with an incidental finding of right homonymous hemianopia and presyncopal spells. Magnetic resonance imaging revealed a vertebrobasilar dolichoectasia (VBD) with compression of the left optic tract. VBD is defined as an elongation and dilatation of the basilar artery. Only a few cases have been described in the literature of VBD causing optic tract compression. So far no treatment option has been described for these cases, while surgical options exist for compressions of other cranial nerves, most commonly the trigeminal nerve. VBD can further cause stroke or cerebral and subarachnoid bleeding.

Terson syndrome in aneurysmal subarachnoid hemorrhage-its relation to intracranial pressure, admission factors, and clinical outcome.

BACKGROUND: A large number of reports have not been able to clarify the pathophysiology of Terson syndrome (TS) in aneurysmal subarachnoid hemorrhage (aSAH). METHODS: Prospective single-center study on aSAH patients. Fundoscopic and radiological signs of TS were assessed. The opening intracranial pressure (ICP) in patients who required a ventriculostomy was recorded with a manometer. RESULTS: Six out of 36 included patients had TS (16.7 %), which was associated with unfavorable admission scores. Twenty-nine patients (80.5 %) required ventriculostomy; TS was associated with higher ICP (median, 40 vs. 15 cm cmH2O, p = .003); all patients with TS had pathological ICP values of >20 cmH2O. Patients with a ruptured aneurysm of the anterior cerebral artery complex were ten times as likely to suffer from TS (OR 10.0, 95 % CI 1.03-97.50). Detection of TS on CT had a sensitivity of 50 %, a specificity of 98.4 %, a positive predictive value of 83.3 %, and a negative predictive value of 92.4 %. Mortality was 45 times as high in patients with TS (OR 45.0, 95 % CI 3.86-524.7) and neurologic morbidity up until 3 months post-aSAH was significantly higher in patients with TS (mRS 4-6; 100 vs. 17 %; p = .001). CONCLUSIONS: Our findings demonstrate an association between raised ICP and the incidence of TS. TS should be ruled out in aSAH patients presenting comatose or with raised ICP to ensure upfront ophthalmological follow-up. In alert patients without visual complaints and a TS-negative CT scan, the likelihood for the presence of TS is very low.

A basic model for training of microscopic and endoscopic transsphenoidal pituitary surgery: the Egghead.

BACKGROUND: Transsphenoidal endoscopic surgery has gained popularity in the last 2 decades and is becoming a standard technique for resection of pituitary adenomas. In contrast to their ENT colleagues, neurosurgical residents have practically no endoscopic experience when they reach the training stage for transsphenoidal procedures. We have developed an affordable method for repetitive training in endoscopic (and microscopic) work in a narrow channel, allowing training of the basic movements needed for resection of pituitary adenoma. METHODS: In collaboration with colleagues in the ENT Department, Cantonal Hospital St. Gall, and the Technical University of Zurich, a three-dimensional model of the nasal cavity was developed and patented. The Egghead model consists of a 3D synthetic reconstruction of the head nasal cavity and sphenoid sinus. A boiled egg represents the sella. For validation, 17 neurosurgical residents from the Department of Neurosurgery, University Hospital of Basel, and Department of Neurosurgery, Cantonal Hospital of St. Gall, St. Gall, Switzerland, and two experts performed a standardized procedure mimicking a transsphenoidal pituitary procedure by dissecting a corridor to the egg yolk and resecting it, respecting the surrounding egg white. This procedure was performed under both microscopic and video-endoscopic visualization. A score for the precision and speed of the surgical performance was developed and used. RESULTS: The model allows repetitive training of the resection of the egg yolk under sparing of the egg white after careful opening of the shell. The validation data showed a steeper learning curve using the endoscopic technique than performing the same task using the microscope. After three repetitions, the quality of resection was better with the endoscopic technique. CONCLUSIONS: Our model, the Egghead, is affordable, offers tactile feedback and allows infinite repetitions in basic training for pituitary surgery. It can be used for training of advanced neurosurgical residents, who thus far have very few possibilities of acquiring endoscopic experience.

Call for uniform neuropsychological assessment after aneurysmal subarachnoid hemorrhage: Swiss recommendations.

BACKGROUND: In a high proportion of patients with favorable outcome after aneurysmal subarachnoid hemorrhage (aSAH), neuropsychological deficits, depression, anxiety, and fatigue are responsible for the inability to return to their regular premorbid life and pursue their professional careers. These problems often remain unrecognized, as no recommendations concerning a standardized comprehensive assessment have yet found entry into clinical routines. METHODS: To establish a nationwide standard concerning a comprehensive assessment after aSAH, representatives of all neuropsychological and neurosurgical departments of those eight Swiss centers treating acute aSAH have agreed on a common protocol. In addition, a battery of questionnaires and neuropsychological tests was selected, optimally suited to the deficits found most prevalent in aSAH patients that was available in different languages and standardized. RESULTS: We propose a baseline inpatient neuropsychological screening using the Montreal Cognitive Assessment (MoCA) between days 14 and 28 after aSAH. In an outpatient setting at 3 and 12 months after bleeding, we recommend a neuropsychological examination, testing all relevant domains including attention, speed of information processing, executive functions, verbal and visual learning/memory, language, visuo-perceptual abilities, and premorbid intelligence. In addition, a detailed assessment capturing anxiety, depression, fatigue, symptoms of frontal lobe affection, and quality of life should be performed. CONCLUSIONS: This standardized neuropsychological assessment will lead to a more comprehensive assessment of the patient, facilitate the detection and subsequent treatment of previously unrecognized but relevant impairments, and help to determine the incidence, characteristics, modifiable risk factors, and the clinical course of these impairments after aSAH.

Neurosurgical and Intensive Care Management of Traumatic Brain Injury.

Optimal management of patients with traumatic brain injury (TBI) remains a challenge, despite significant improvements in pathophysiologic understanding and treatment strategies in recent decades. Because primary brain injury sustained at the time of trauma is irreversible, the TBI management mainly aims for early detection and treatment of secondary brain injury such as space-occupying intracerebral hematomas and brain edema. Prevention of secondary brain injury requires a high standard of care and understanding of both medical and surgical treatment modalities. This review focuses on practical recommendations for neurosurgical and intensive care management in patients with severe TBI.

Traumatic Brain Injury in Alpine Winter Sports: Comparison of Two Case Series from a Swiss Trauma Center 30 Years Apart.

BACKGROUND: Between 3 and 15% of winter sports-related injuries are related to head injuries, which are the primary cause of mortality and disability among skiers. Despite the widespread adoption of helmets in winter sports, which has reduced the incidence of direct head injury, there is a paradoxical trend of an increasing number of individuals wearing helmets sustaining diffuse axonal injuries (DAI), which can result in severe neurologic sequelae. METHODS: We retrospectively reviewed 100 cases collected by the senior author of this work from 13 full winter seasons during the period from 1981 to 1993 and compared them with 17 patients admitted during the more shortened 2019 to 2020 ski season due to COVID-19. All data analyzed come from a single institution. Population characteristics, mechanism of injury, helmet use, need for surgical treatment, diagnosis, and outcome were collected. Descriptive statistics were used to compare the two databases. RESULTS: From February 1981 to January 2020, most skiers with head injuries were men (76% for the 1981-1993 and 85% for 2020). The proportion of patients aged over 50 increased from <20% in 1981 to 65% in 2020 (p < 0.01), with a median age of 60 years (range: 22-83 years). Low- to medium-velocity injuries were identified in 76% (13) of cases during the 2019 to 2020 season against 38% (28/74) during the 1981 to 1993 seasons (p < 0.01). All injured patients during the 2020 season wore a helmet, whereas none of the patients between 1981 and 1993 wore one (p < 0.01). DAI was observed in six cases (35%) for the 2019 to 2020 season against nine cases (9%) for the 1981 to 1993 season (p < 0.01). Thirty-four percent (34) of patients during the 1981 to 1993 seasons and 18% (3) of patients during the 2019 to 2020 season suffered skeletal fractures (p = 0.02). Among the 100 patients of the 1981 to 1993 seasons, 13 (13%) died against 1 (6%) from the recent season during care at the hospital (p = 0.15). Neurosurgical intervention was performed in 30 (30%) and 2 (12%) patients for the 1981 to 1993 and 2019 to 2020 seasons, respectively (p = 0.003). Neuropsychological sequelae were reported in 17% (7/42) of patients from the 1981 to 1993 seasons and cognitive evaluation before discharge detected significant impairments in 24% (4/17) of the patients from the 2019 to 2020 season (p = 0.29). CONCLUSION: Helmet use among skiers sustaining head trauma has increased from none in the period from 1981 to 1993 to 100% during the 2019 to 2020 season, resulting in a reduction in the number of skull fractures and deaths. However, our observations suggest a marked shift in the type of intracranial injuries sustained, including a rise in the number of skiers experiencing DAI, sometimes with severe neurologic outcomes. The reasons for this paradoxical trend can only be speculated upon, leading to the question of whether the perceived benefits of helmet use in winter sports are actually misinterpreted.

The interdural hematoma: A subtype of convexity subdural/dural hematoma with specific radioanatomical characteristics.

Background: Rare cases of biconvex hematomas splitting the convexity dura mater were reported and denominated interdural hematoma (IDH). Due to their rarity, little is known about their radiological characteristics, and in most cases, their invasive management with craniotomy and dural membrane excision is unnecessary. Case Description: We report here a case of single burr-hole endoscopic evacuation of an IDH and its complete resolution after the 6-month follow-up imaging. The literature review reveals 11 reported cases of IDH. Most of them are male and the mean age is 65 years (range 51-90). Most of the reported IDHs were misdiagnosed as epidural hematoma or meningioma, and therefore, they have been managed invasively through craniotomy with dural excision. Diagnosis of the interdural nature was confirmed macroscopically during surgery in all cases and histology was reported for 6 cases. Image analysis found a double dural beak sign and biconvex shape on coronal planes, subarachnoid space enlargement at the collection extremities, and irregular thick inner wall as common radiological aspects of the IDH. Conclusion: IDH is a rarely reported and often misdiagnosed dural hematoma subtype. Its invasive treatment through craniotomy is likely related to its unknown radiological characteristics. We review and raise awareness about potentially unique radiological anatomy that could avoid unnecessary invasive treatment. Moreover, we report the first case of endoscopically evacuated IDH with long-term follow-up imaging showing complete resolution.

Late metachronous cerebral metastasis of pancreatic adenocarcinoma of the tail of the pancreas: a case report.

BACKGROUND: Pancreatic cancer is one of the leading causes of cancer mortality and one of the most lethal malignant neoplasms worldwide. It is known for its local tumor extension to the liver; other common sites include the lung, distant lymph nodes, and bone. Brain metastases are extremely rare and represent less than 0.6% of all brain metastases. CASE REPORT: We report the case of a 66-year-old Caucasian female known to have adenocarcinoma of the tail of the pancreas treated with chemotherapy. During follow-up, thoracoabdominal computed tomography scans did not reveal any residual tumor or any metastasis. Moreover, tumor markers were within normal limits. She presented to the emergency department of our institution following an episode of a generalized tonic-clonic seizure 5 years following the initial diagnosis. Brain magnetic resonance imaging revealed an expansive left frontal intraaxial lesion compatible with high-grade glioma. The patient underwent surgical treatment. Histological examination revealed pancreatic metastasis. CONCLUSIONS: Thought to be rare, metachronous cerebral pancreatic metastasis should be kept in mind in patients with pancreatic cancer. Early diagnosis and complete surgical resection play a key role in the survival of these patients.

Full-Endoscopic Resection of a Recurrent Posterior Longitudinal Ligament Cyst: Technical Note.

BACKGROUND: Posterior longitudinal ligament cysts are very rare lesions and do not usually recur. Microscopic resection is commonly performed. The aim of this article was to report a case of recurrent posterior longitudinal ligament cyst that benefited from full-endoscopic resection. METHODS: We used the 25° endoscope of the RIWOspine set for interlaminar approach. A step-by-step description of the surgical technique was presented. RESULTS: Clinical evolution was favorable. The patient remained pain-free 1 month after surgery, and postoperative magnetic resonance imaging showed complete resection of the cyst. CONCLUSIONS: Endoscopy is a safe and feasible approach for posterior longitudinal ligament cysts, including unusual recurrent cases.

Web-based audiovisual patient information system--a study of preoperative patient information in a neurosurgical department.

BACKGROUND: In the current climate of increasing awareness, patients are demanding more knowledge about forthcoming operations. The patient information accounts for a considerable part of the physician's daily clinical routine. Unfortunately, only a small percentage of the information is understood by the patient after solely verbal elucidation. To optimise information delivery, different auxiliary materials are used. METHODS: In a prospective study, 52 consecutive stationary patients, scheduled for an elective lumbar disc operation were asked to use a web-based audiovisual patient information system. A combination of pictures, text, tone and video about the planned surgical intervention is installed on a tablet personal computer presented the day before surgery. All patients were asked to complete a questionnaire. RESULTS: Eighty-four percent of all participants found that the audiovisual patient information system lead to a better understanding of the forthcoming operation. Eighty-two percent found that the information system was a very helpful preparation before the pre-surgical interview with the surgeon. Ninety percent of all participants considered it meaningful to provide this kind of preoperative education also to patients planned to undergo other surgical interventions. Eighty-four percent were altogether "very content" with the audiovisual patient information system and 86% would recommend the system to others. CONCLUSIONS: This new approach of patient information had a positive impact on patient education as is evident from high satisfaction scores. Because patient satisfaction with the informed consent process and understanding of the presented information improved substantially, the audiovisual patient information system clearly benefits both surgeons and patients.

[Aneurysmal subarachnoid hemorrhage - therapy and complications]. / Aneurysmatische Subarachnoidalblutung - Diagnostik und Therapie zerebraler und systemischer Komplikationen.

The management of patients with aneurysmal subarachnoid hemorrhage (SAH) requires a fundamental knowledge of the disease, its therapeutic options and possible complications. The preoperative goal is to prevent rebleeding by controlling blood pressure and treating pain and anxiety as well as stabilizing cardiopulmonary functions. An acute hydrocephalus has to be treated immediately. Microsurgical clipping or endovascular coiling are the therapeutic options available. The postoperative goal aims at securing cardiopulmonary functions as well as recognizing and treating cerebral (cerebral vasospasm, hydrocephalus, epilepsy) and systemic complications (electrolyte disorder, cardiac dysfunction). This article provides an overview about the pre-, peri- and postoperative management of patients with SAH.

[Normal pressure hydrocephalus]. / Hydrocéphalie à pression normale.

Normal pressure hydrocephalus (NPH) is characterized by a classic triad of symptoms including gait disturbance, urinary incontinence, and dementia. NPH is associated with a radiological verifiable ventriculomegaly in the absence of elevated cerebrospinal fluid (CSF) pressure. Because many patients do not present with classical clinical and radiological findings, its diagnosis and management represents a challenge for the treating doctor. Various supplemental preoperative tests, including lumbar CSF tap test or CSF outflow resistance determination, can improve the accuracy of predicting a response to surgical intervention. CSF shunt results in significant reduction of the symptoms in the majority of appropriately evaluated patients.

Spontaneous transethmoidal meningoencephalocele presenting in the form of recurrent unilateral nasal discharge: discussion of the diagnosis and endoscopic surgical management.

Meningoencephaloceles of the skull base most commonly occur as a sequela of head trauma or they can more rarely be congenital malformations. Several types of encephalocele exist depending on anatomic features and localisation. Clinical presentation and symptoms can vary. Different methods of management and repair of the concurring skull base defects have been described and ranging vary from endoscopic to open surgical approaches. We report the case of a 56-year-old Caucasian woman with the diagnosis of right sided spontaneous transethmoidal meninoencephalocele. Clinical presentation of this rare pathology, methods of diagnostic and management and its outcome are presented. Spontaneous skull base meningoencephaloceles are rare entities, without clear underlying etiologies. Multidisciplinary management is recommended. The transnasal endoscopic approach provides a wide skull base exposure with more advantages and less morbidity in comparison with the conventional open approach.