Assessment of CSF dynamics using infusion study: tips and tricks.

Idiopathic normal pressure hydrocephalus, secondary chronic hydrocephalus, and other cerebrospinal fluid (CSF) disorders are often challenging to diagnose. Since shunt surgery is usually the only therapeutic option and carries significant morbidity, optimal patient selection is crucial. The tap test is the most commonly used prognostic test to confirm the diagnosis but lacks sensitivity. The Lumbar Infusion Study (LIS) appears to be a better option, offering additional information on brain dynamics without increasing morbidity. However, this technique remains underused. In this narrative review, supported by the extensive experience of several European expert centers, we detail the physiological basis, indications, and CSF dynamics parameters that can be measured. We also discuss technical modalities and variations, including one vs. two needles, patient positioning, and the site of CSF measurement, as well as in vivo shunt testing. Finally, we discuss the limitations and morbidity associated with the LIS. This review aims to assist teams wishing to incorporate LIS into their screening tools for chronic hydrocephalus and other CSF disorders.

Combined Endoscopic Transmaxillary Approach for Resection of an Extracranial V3 Schwannoma: 2-Dimensional Operative Video.

Tumours of the pterygopalatine (PPF) and infratemporal fossa (ITF) are rare tumours and are difficult to access. The lateral cervical approach is hampered by the mandibular angle and the vascular nervous elements.1 The classic endonasal endoscopic medial maxillectomy approach has been developed over the past 2 decades but does not allow good control of the most lateral and inferior part of the ITF.2 The surgical video presents a 68-year-old woman with trigeminal neuralgia. The radiologic workup showed a trigeminal V3 schwannoma (TS) into the PPF and ITF. This tumor grew during the follow-up despite fractionated radiosurgery. A 2-dimensional intraoperative video illustrates the gross total removal of the TS through a combined endoscopic endonasal and transgingival transmaxillary approach. The combination of these 2 approaches allows on the one hand, a better view of the lateral and inferior part of the maxillary sinus and ITF and on the other hand, a gain of handling in the operating field and security for our surgical procedure.3 The mini-Caldwell-Luc approach gives good aesthetic results without stomatological complication. Neuralgia disappeared after the surgery, and a gross total resection was achieved, and no recurrence was observed during the follow-up. This combined approach is a good alternative of medial extended maxillectomy, which presents a risk for the lacrimal duct risk and postoperative aesthetic deformity because of the removal of the medial and anterior wall of the maxillary sinus. The patient consented to the procedure and publication of her image.

Endonasal Endoscopic Optic Canal Decompression for Nontraumatic Optic Neuropathy: Long-Term Visual Outcomes in 36 Patients.

BACKGROUND: The management of compressive optic neuropathy (CON) arising from nontraumatic compression of the optic nerve within the optic canal (OC) remains a topic of controversy. In this study, our aim was to assess the effectiveness and safety of endonasal endoscopic optic nerve decompression (EEOND). In addition, we conducted an analysis of prognostic factors that could potentially influence visual outcomes. METHODS: This retrospective cohort study was conducted between January 2015 and December 2021, involving adult patients (age > 18) diagnosed with CON and treated with EEOND at our specialized skull base expert center. The study evaluated the impact of surgery on visual acuity (VA), mean deficit (MD), and foveal threshold (FT) of the visual field (VF). These parameters were assessed preoperatively and at 3- and 12-month postoperative follow-ups. The relationship between clinical variables and the differences in postoperative to preoperative VA, MD, and FT of the visual field was analyzed through univariate and multivariate approaches. RESULTS: Thirty-six patients (38 eyes) were included, with a mean age of 52 (±12) years, and a female predominance (78%). The mean ophthalmologic follow-up duration was 38 (±32) months. At the 12-month follow-up, 39% of the patients exhibited a VA improvement of ≥0.2 LogMAR. Partial VF improvement (MD improvement ≥25%) was observed in 55% of the patients, whereas 19% experienced complete recovery. In multivariate analysis, the presence of a type 4 OC was identified as the sole negative prognostic factor for visual improvement (VA and VF) at 12 months. Six patients (17%) encountered minor surgical complications, all of which were managed conservatively and had no impact on visual outcomes. CONCLUSIONS: Our study demonstrates that EEOND is a safe and effective procedure, even in cases of severe and long-lasting CON caused by nontraumatic compression of the optic nerve at the level of the OC.

Frontal trans-sinusal approach: how I do it.

BACKGROUND: Anterior skull base lesions could be reached by different approaches (subfrontal, pterional, interhemispheric, etc.). In selected cases, the frontal trans-sinusal approach is an effective alternative to conventional techniques. METHODS: We present our technique to perform a frontal trans-sinusal approach in a patient affected by a large olfactory groove meningioma. DISCUSSION-CONCLUSION: The frontal trans-sinusal approach allows to approach safely lesions of the median anterior cranial fossa. This approach provides lower brain retraction, easier access to olfactory grooves, and earlier tumor devascularization. However, it remains limited to patients with large-sized frontal sinuses and entails some postoperative risks such as mucocele or CSF leak.

Pediatric Posterior Fossa ATRT: A Case Report, New Treatment Strategies and Perspectives.

Posterior fossa atypical teratoid rhabdoid tumor (ATRT) is a rare childhood tumor usually associated with a dismal prognosis. Although upfront surgical gross total resection (GTR) has classically been the first line of treatment, new multimodal treatments, including two-stage surgery, are showing promising results in terms of overall survival (OS) and complication rate. We present a case of a 9-month-old child treated with two-staged surgery and chemotherapy. When deemed risky, multimodal treatments, including staged surgeries, can be a safe alternative to reduce surgical mortality and morbidity. At 23 months old, the patient had normal global development and no major impact on quality of life. We, therefore, discuss the most recent advancements from a treatment perspective, including molecular targeting.

Current Advances in Papillary Craniopharyngioma: State-Of-The-Art Therapies and Overview of the Literature.

Craniopharyngiomas are commonly classified as low-grade tumors, although they may harbor a malignant behavior due to their high rate of recurrence and long-term morbidity. Craniopharyngiomas are classically distinguished into two histological types (adamantinomatous and papillary), which have been recently considered by the WHO classification of CNS tumors as two independent entities, due to different epidemiological, radiological, histopathological, and genetic patterns. With regard to papillary craniopharyngioma, a BRAF V600 mutation is detected in 95% of cases. This genetic feature is opening new frontiers in the treatment of these tumors using an adjuvant or, in selected cases, a neo-adjuvant approach. In this article, we present an overview of the more recent literature, focusing on the specificities and the role of oncological treatment in the management of papillary craniopharyngiomas. Based on our research and experience, we strongly suggest a multimodal approach combining clinical, endocrinological, radiological, histological, and oncological findings in both preoperative workup and postoperative follow up to define a roadmap integrating every aspect of this challenging condition.

Severe Basilar impression in osteogenesis imperfecta treated with halo gravity traction, occipitocervicothoracic fusion, foramen magnum and upper cervical decompression and expansive duroplasty: a technical note.

Osteogenesis imperfecta (OI) is a rare bone disease due to an abnormal synthesis of 1-type collagen. OI is frequently associated with basilar impression (BI), defined by the elevation of the clivus and floor of the posterior fossa with subsequent migration of the upper cervical spine and the odontoid peg into the base of the skull. Bone intrinsic fragility leading to fractures and deformity, brainstem compression and impaired CSF circulation at cranio-vertebral junction (CVJ) makes the management of these conditions particularly challenging. Different surgical strategies, including posterior fossa decompression with or without instrumentation, transoral or endonasal decompression with posterior occipito-cervical fusion, or halo gravity traction with posterior instrumentation have been reported, but evidence about best modalities treatment is still debated. In this technical note, we present a case of a 16-years-old patient, diagnosed with OI and BI, treated with halo traction, occipito-cervico-thoracic fixation, foramen magnum and upper cervical decompression, and expansive duroplasty. We focus on technical aspects, preoperative work up and postoperative follow up. We also discuss advantages and limitations of this strategy compared to other surgical techniques.

Atlantoaxial posterior screw fixation using intra-operative spinal navigation with three-dimensional isocentric C-arm fluoroscopy.

PURPOSE: Intra-operative image acquisition coupled with navigation aims to increase screw placement accuracy, and it is particularly helpful in complex spinal procedures. The aim of this study is to analyze the accuracy and reliability of posterior atlanto-axial fixation using spinal navigation combined with intra-operative 3D isocentric C-arm. METHODS: We retrospectively reviewed all patients presenting with C1-C2 instability and treated by posterior atlanto-axial fixation in our center between December 2016 and September 2018. Screw positioning was guided by intra-operative navigation, registered with surface matching procedure on a previously obtained CT scan and controlled by intra-operative 3D isocentric C-arm. Age, sex, pre- and post-operative neurological status, duration of surgery, presence/absence of vertebral artery injury, and screw placement were retrospectively collected from patients' records. All patients underwent clinical and radiological follow-up at three months after surgery. Radiological assessment of screw positioning was performed by an independent radiologist using the Gertzbein and Robbins grading. RESULTS: N = 11 (7F, 4 M) consecutive patients were included, with a mean age of 72 years (range from 51 to 85). N = 44 navigated screws were inserted and controlled with intra-operative 3D fluoroscopy at the end of the procedure. An acceptable screw positioning (Gertzbein-Robbins grade A and B) was obtained in all cases (100%). No vertebral artery injury was observed. Mean operating time was 123 minutes. At three months, no screw loosening or displacement was observed. CONCLUSION: In our experience, spinal navigation coupled with intra-operative 3D fluoroscopy proved to be reliable and safe for C1-C2 screw placement.

From Focused Ultrasound Tumor Ablation to Brain Blood Barrier Opening for High Grade Glioma: A Systematic Review.

BACKGROUND: Focused Ultrasound (FUS) is gaining a therapeutic role in neuro-oncology considering its novelty and non-invasiveness. Multiple pre-clinical studies show the efficacy of FUS mediated ablation and Blood-Brain Barrier (BBB) opening in high-grade glioma (HGG), but there is still poor evidence in humans, mainly aimed towards assessing FUS safety. METHODS: With this systematic review our aim is, firstly, to summarize how FUS is proposed for human HGG treatment. Secondly, we focus on future perspectives and new therapeutic options. Using PRISMA 2020 guidelines, we reviewed case series and trials with description of patient characteristics, pre- and post-operative treatments and FUS outcomes. We considered nine case series (five about tumor ablation and four about BBB opening) with FUS-treated HGG patients between 1991 and 2021. RESULTS: Sixty-eight patients were considered in total, mostly males (67.6%), with a mean age of 50.5 ± 15.3 years old. Major complication rates were found in the tumor ablation group (26.1%). FUS has been rarely applied for direct tumoral ablation in human HGG patients with controversial results, but at the best of current studies, FUS-mediated BBB opening is showing good results with very low complication rates, paving the way for a new reliable technique to improve local chemotherapy delivery and antitumoral immune response. CONCLUSIONS: FUS can become a complementary technique to surgical resection and standard radiochemotherapy in recurrent HGG. Ongoing trials could provide in the near future more data on FUS-mediated BBB opening impact on progression-free survival, overall survival and potential drug-delivery capacities.

Endoscopic resection of a low-grade ependymoma of the pineal region.

BACKGROUND: Full endoscopic resection of solid brain tumors represents a challenge for neurosurgeons. This can be achieved with modern technology and advanced surgical tools. CASE DESCRIPTION: A 23-years-old male was referred to our unit with raised intracranial pressure. Head computed tomography and magnetic resonance imaging (MRI) revealed obstructive hydrocephalus and a third ventricle lesion. Endoscopic third ventriculostomy and biopsy were performed, a left frontal external ventricular drain was left in place. A second-look surgery for endoscopic removal was planned. Decision to proceed with an endoscopic removal was supported by the following characteristics found during the first surgery: tumor exophytic, soft texture, scarce vascularity, and low-grade appearance. A rescue strategy for microscopic resection via transcallosal approach was decided. A straight trajectory to the tumor was planned with navigation. A further anterior left frontal burr-hole was performed, and the ventricular system was entered via the left frontal horn. Resection was carried out alternating laser for hemostasis and cutting, endoscopic ultrasonic aspirator, and endoscopic forceps for piecemeal resection. Laser hemostasis and cutting (1 Watt power at tip, continuous wave mode) were useful at the ventricular wall-tumor interface. Relevant landmarks guided the approach and the resection (foramen of Monro, mammillary bodies, aqueduct, pineal and suprapineal recess, and posterior commissure). The surgery was carried uneventfully. Histopathology confirmed a lowgrade ependymoma. Post-operative MRI showed residual tumor within the lower aqueduct. At 3 years follow-up, residual tumor is stable. CONCLUSION: In selected cases, endoscopic resection for third ventricular tumors is feasible and safe, and represents a valid alternative to microsurgical approaches.

Isolated subarachnoid hemorrhage in mild traumatic brain injury: is a repeat CT scan necessary? A single-institution retrospective study.

BACKGROUND: Traumatic brain injury (TBI) with isolated subarachnoid hemorrhage (iSAH) is a common finding in the emergency department. In many centers, a repeat CT scan is routinely performed 24 to72 h following the trauma to rule out further radiological progression. The aim of this study is to assess the clinical utility of the repeat CT scan in clinical practice. METHODS: We reviewed the medical charts of all patients who presented to our institution with mild TBI (mTBI) and isolated SAH between January 2015 and October 2017. CT scan at admission and control after 24 to 72 h were examined for each patient in order to detect any possible change. Neurological deterioration, antiplatelet/anticoagulant therapy, coagulopathy, SAH location, associated injuries, and length of stay in hospital were analyzed. RESULTS: Of the 649 TBI patients, 106 patients met the inclusion criteria. Fifty-four patients were females and 52 were males with a mean age of 68.2 years. Radiological iSAH progression was found in 2 of 106 (1.89) patients, and one of them was under antiplatelet therapy. No neurological deterioration was observed. Ten of 106 (9.4%) patients were under anticoagulation therapy, and 28 of 106 (26.4%) were under antiplatelet therapy. CONCLUSION: ISAH in mTBI seems to be a radiological stable entity over 72 h with no neurological deterioration. The clinical utility of a repeat head CT in such patients is questionable, considering its radiation exposure and cost. Regardless of anticoagulation/antiplatelet therapy, neurologic observation and symptomatic treatment solely could be a reasonable alternative.

Surgical challenges in posterior cervicothoracic junction instrumentation.

The cervicothoracic junction (CTJ) is a region of the spine submitted to significant mechanical stress. The peculiar anatomical and biomechanical characteristics make posterior surgical stabilization of this area particularly challenging. We present and discuss our surgical series highlighting the specific surgical challenges provided by this region of the spine. We have analyzed and reported retrospective data from patients who underwent a posterior cervicothoracic instrumentation between 2011 and 2019 at the Neurosurgical Department of the Geneva University Hospitals. We have discussed C7 and Th1 instrumentation techniques, rods design, extension of constructs, and spinal navigation. Thirty-six patients were enrolled. We have preferentially used lateral mass (LM) screws in the subaxial spine and pedicle screws (PS) in C7, Th1, and upper thoracic spine. We have found no superiority of 3D navigation techniques over 2D fluoroscopy guidance in PS placement accuracy, probably due to the relatively small case series. Surgical site infection was the most frequent complication, significantly associated with tumor as diagnosis. When technically feasible, PS represent the technique of choice for C7 and Th1 instrumentation although other safe techniques are available. Different rod constructs are described although significant differences in biomechanical stability still need to be clarified. Spinal navigation should be used whenever available even though 2D fluoroscopy is still a safe option. Posterior instrumentation of the CTJ is a challenging procedure, but with correct surgical planning and technique, it is safe and effective.

Craniocervical fractures management in case of craniocervical pneumatization: case report and review of the literature.

INTRODUCTION: Extensive craniocervical pneumatization (CCP) refers to an abnormal pneumatization extended from the temporal bone into adjacent bone structures, especially the skull base and the craniocervical junction. The etiology remains controversial; however several studies reported a correlation with recurrent Valsalva maneuvers or Eustachian tube dysfunction. Although some cases requiring surgical treatment have been reported, conservative treatment remains the gold standard. The authors aimed to describe a case of CCP, complicated by a spontaneous fracture of a pneumatized left occipital condyle. Furthermore, they reviewed all previously reported cases of fractures in CCP in order to propose a standardized approach to this pathology. METHODS: A total of 148 studies were retrieved. Of those, 23 studies (including 26 patients in addition to our case) were included in the review. These studies consisted of case reports or small case series (up to 3 patients). RESULTS: In 3 patients (11.1%), bone pneumatization involved C0; all remaining patients had both C0 and C1 pneumatization, while in 7 cases (25.9%), an extension to C2 and/or C3 was reported. Radiological follow-up was performed in 20 patients (74.1%), showing in all of the cases either stability (6 patients, 22.2%), improvement, or complete resolution (6 patients, 22.2% vs 8 patients, 29.7%). Two patients underwent surgical intervention. CONCLUSIONS: This review suggests that fractures secondary to CCP are extremely rare and are associated to a good clinical and radiological outcome with conservative treatment. Ear, nose, and throat (ENT) evaluation is recommended to detect cases who need treatment for a subjacent middle ear disease.

Does Spondylolisthesis Affect Severity and Outcome of Degenerative Cervical Myelopathy? A Systematic Review and Meta-analysis.

STUDY DESIGN: This was a systematic review and meta-analysis. OBJECTIVES: Degenerative cervical myelopathy (DCM) with spondylolisthesis remains not well defined, poorly studied, and underreported and plays a minor role in the therapeutic decision-making. Spondylolisthesis, however, is not uncommon and may result in dynamic injury to the spinal cord. We aim to describe the impact of spondylolisthesis in DCM severity and postoperative outcomes. METHODS: Two independent reviewers conducted a Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA 2015)-based review between 1970 and May 2020 for articles reporting outcome of DCM in patients with degenerative cervical spondylolisthesis. Patient clinical and radiological data was recorded at baseline and during postoperative follow-up (FU). A meta-analysis comparing surgical outcome between DCM patients with and without spondylolisthesis assessed by the regular/modified Japanese Orthopaedic Association Assessment Scale (mJOA) recovery ratio was completed. RESULTS: A total of 3 studies were included (1 ambispective and 2 retrospective cohorts); 607 patients with DCM were identified, 102 (16.8%) of whom also had spondylolisthesis. DCM patients with spondylolisthesis were significantly older (P < .05), presented with worse baseline mJOA and Nurick grades (P < .05 in 2 studies), and were more commonly operated via posterior approaches (P < .05). All groups experienced a (m)JOA and/or Neck Disability Index score improvement during FU. In the pooled meta-analysis, spondylolisthesis patients showed a significantly lower functional recovery ratio at 2 years compared with other DCM patients (P = .05). CONCLUSIONS: Spondylolisthesis is frequent in older DCM patients and may be a predictor of a more advanced degeneration and subsequent worse baseline conditions and postoperative outcome.

Navigation assisted tubular resection of lumbar osteoid osteoma: how I do it.

BACKGROUND: Osteoid osteoma is a benign primary bony tumor involving the spinal posterior arches. Surgical treatment is reserved to patients with severe pain or not responding to nonsteroidal anti-inflammatory medications. We report a minimally invasive transmuscular resection of an L5 isthmic osteoid osteoma, assisted by intraoperative 3D-fluoroscopy-based navigation. METHODS: Navigation tracking reference is placed on the spinous process. A simil-scan with 3D-fluoroscopy is obtained to allow autoregistration for spinal navigation. Tubular transmuscular approach, directed to the ipsilateral isthmus and pedicle, is performed. Under navigation guidance, the lesion is identified and removed. CONCLUSION: This technique is a safe and effective minimally invasive alternative to conventional surgical treatment of lumbar osteoid osteoma.

Degenerative Cervical Myelopathy: Review of Surgical Outcome Predictors and Need for Multimodal Approach.

Degenerative cervical myelopathy is the most common cause of spinal cord injury in the elderly population in the developed world, and it significantly affects the quality of life of patients and their caregivers. Surgery remains the only treatment option able to halt disease progression and provide neurological recovery for most patients. Although it has remained challenging to predict exactly who will experience improvement after surgery, increasingly it has been shown that clinical, imaging, and electrophysiological factors can predict, with relatively good capacity, those more likely to benefit. Clinically, the baseline neurological impairment appears to be strongly related to the outcome, and the magnetic resonance imaging findings of T1-weighted hypointensity and the length of T2-weighted hyperintensity appear to be the most prognostic. In this context, electrophysiology findings (both motor and sensory evoked potentials) have shown some predictive capacity. However, large studies are lacking. Although multivariate models have been conducted using clinical and magnetic resonance imaging data, no multimodal prediction models are available that encompass the predictive capacity of clinical, imaging, and electrophysiological data. In the present review, we examined the rationale for clinical, imaging, and electrophysiological usage in clinical practice and discussed a model of multimodal assessment for the management of degenerative cervical myelopathy.

Dual Pathologies: Pial Arteriovenous Fistula in Combination with an Arteriovenous Malformation.

BACKGROUND: A pial arteriovenous fistula (PAVF) is a rare neurovascular pathology consisting of a direct connection between one or more arterial feeders and a single venous channel. A PAVF was previously considered a subtype of an arteriovenous malformation (AVM). In the current literature these are distinguished as two independent entities with different clinical, physiopathologic, and structural characteristics. We report a case of a surgically treated 37-year-old woman with an extremely rare combination of an unruptured PAVF and AVM. PATIENT: The AVM was mainly supplied by feeders of the middle cerebral artery and drained into the sigmoid sinus via an abnormally dilated and tortuous vein. Following its resection, intraoperative digital subtraction angiography (DSA) in the hybrid operating room revealed the presence of a PAVF that had not been noted during the preoperative planning. Hence the PAVF was completely disconnected as confirmed by DSA again. CONCLUSION: This is the second reported case of an AVM-associated PAVF. Without the intraoperative DSA in the hybrid operating room, this unusual complex cerebrovascular entity would likely have been missed.

Symptomatic tandem spinal stenosis: a clinical, diagnostic, and surgical challenge.

Tandem spinal stenosis (TSS) is an entity which refers to spinal canal diameter narrowing in at least two distinct regions of the spine. When symptomatic, management of TSS is controversial. In this study, we present a consecutive series of patients with symptomatic TSS and report diagnostic and surgical challenges. We retrospectively reviewed a consecutive series of N = 8 patients with symptomatic TSS who underwent surgical treatment in at least one region of the spine. Patients presented with multiple complaints, including neurogenic claudication, progressive gait disturbances, and signs of radiculopathy and/or myelopathy, among others. Modified Japanese Orthopedic Association (mJOA) and Oswestry Low Back Pain Disability Questionnaire (ODI) were obtained in pre- and postoperative period. Electroneurophysiological examinations were limited to patients whose clinical and radiological signs were not sufficient to determine which region was more affected. From 2015 to 2018, we included N = 8 consecutive patients with TSS who underwent surgery by a staged approach. The stenosis was localized in the cervical and lumbar region in six patients (75%) and in the cervical, dorsal, and lumbar level (triple TSS) in two patients (25%). Four patients (50%) underwent cervical and lumbar surgery, two (25%) underwent cervical surgery alone, and two (25%) were operated in all three involved regions. Surgical treatment allowed an improvement of the mean mJOA score (from 12.5/17 to 15/17) and mean ODI score (from 41 to 28%). TSS represents a clinical, diagnostic, and surgical challenge. We recommend to systematically obtain electrophysiological and radiological examinations and then to perform a staged surgery, beginning at the most symptomatic region.

Total thyroidectomy with harmonic scalpel combined to gelatin-thrombin matrix hemostatic agent: is it safe and effective? A single-center prospective study.

INTRODUCTION: Hemostasis during thyroidectomy is essential; however, the safest, most efficient and cost-effective way to achieve this is unclear. The aim of this study was to evaluate the outcome of total thyroidectomy (TT) performed with combination of harmonic scalpel (HS) and Floseal. METHODS: Patients undergone TT were divided into two groups: HS + Floseal and traditional hemostasis groups. The primary endpoint was 24-h drain output and blood-loss requiring reintervention. Secondary endpoints included surgery duration, postsurgical complications and hypocalcemia rates. RESULTS: Between September 2012 and January 2014, 165 patients were enrolled (100 to HS + Floseal, 65 to standard hemostasis); 80.5% female; mean age 42.3 years. The 24-h drain output was lower in the HS + Floseal group compared with standard TT. HS + Floseal also had a shorter mean surgery time (p < 0.0001) vs standard TT. No differences in post-surgical complications and in hypocalcemiarates between groups. CONCLUSION: combination of Floseal plus the HS is effective and safe for TT and it provides a complementary hemostatic approach.