Compartmental Cerebrospinal Fluid Events Occurring after Subarachnoid Hemorrhage: An "Heparin Oriented" Systematic Review.

Subarachnoid hemorrhage (SAH) represents a severe acute event with high morbidity and mortality due to the development of early brain injury (EBI), secondary delayed cerebral ischemia (DCI), and shunt-related hydrocephalus. Secondary events (SSE) such as neuroinflammation, vasospasm, excitotoxicity, blood-brain barrier disruption, oxidative cascade, and neuronal apoptosis are related to DCI. Despite improvement in management strategies and therapeutic protocols, surviving patients frequently present neurological deficits with neurocognitive impairment. The aim of this paper is to offer to clinicians a practical review of the actually documented pathophysiological events following subarachnoid hemorrhage. To reach our goal we performed a literature review analyzing reported studies regarding the mediators involved in the pathophysiological events following SAH occurring in the cerebrospinal fluid (CSF) (hemoglobin degradation products, platelets, complement, cytokines, chemokines, leucocytes, endothelin-1, NO-synthase, osteopontin, matricellular proteins, blood-brain barrier disruption, microglia polarization). The cascade of pathophysiological events secondary to SAH is very complex and involves several interconnected, but also distinct pathways. The identification of single therapeutical targets or specific pharmacological agents may be a limited strategy able to block only selective pathophysiological paths, but not the global evolution of SAH-related events. We report furthermore on the role of heparin in SAH management and discuss the rationale for use of intrathecal heparin as a pleiotropic therapeutical agent. The combination of the anticoagulant effect and the ability to interfere with SSE theoretically make heparin a very interesting molecule for SAH management.

Complications in AVM Surgery.

In AVM surgery perioperative complications can arise and can have serious perioperative consequences. Surgically related complications in AVM treatment, in many cases, can be avoided by paying attention to details:1. Careful selection of the patient: - addressing a patient with eloquent AVM to Gamma Knife treatment - preoperative treatment with selective embolization of the accessible deep feeders - preoperative gamma knife or embolize those patient with an over-expressed venous pattern2. Meticulous coagulation of deep medullary feeders: - Using dirty coagulation - Using dry non-stick coagulation - Using micro clips - Using laser - Reaching the choroidal vessel in the ventricle when possible - Avoiding occlusive coagulation with hemostatic agents3. Check and avoiding any residual of the AVM4. Keep the patient under pressure control during postoperative periodFulfilling these steps contributes to reduce complications in this difficult surgery, leading to a safer treatment that compares favorably with natural history of brain arteriovenous malformations.

Intracranial Dural Arteriovenous Fistulas: The Sinus and Non-Sinus Concept.

INTRODUCTION: Dural arteriovenous fistulas (dAVFs) account for 10-15% of all intracranial arteriovenous lesions. Different classification strategies have been proposed in the course of the years. None of them seems to guide the treatment strategy. OBJECTIVE: We expose the experience of the vascular group at Niguarda Hospital and we propose a very practical classification method based on the location of the shunt. We divide dAVF in sinus and non-sinus in order to simplify our daily practice, as this classification method is simply based on the involvement of the sinuses. MATERIAL AND METHODS: 477 intracranial dural arteriovenous fistulas have been treated. 376 underwent endovascular treatment and 101 underwent surgical treatment. Cavernous sinus DAVFs and Galen ampulla malformations have been excluded from this series as they represent a different pathology per se. 376 dAVFs treated by endovascular approach: 180 were sinus and 179 were non-sinus. 101 dAVFs treated with surgical approach: 15 were sinus and 86 were non-sinus. DISCUSSION: Of the 477 intracranial dAVF the recorded mortality and severe disability was 3% and morbidity less than 4%. All patients underwent a postoperative DSA with nearly 100% of complete occlusion of the fistula. At a mean follow-up of 5 years in one case there was a non-sinus fistula recurrence, due to the presence of a partial clipping of "piè" of the vein. CONCLUSIONS: The sinus and non-sinus concept has guided our institution for years and has led to good clinical results. This paper intends to share this practical classification with the neurosurgical community.

Pelvic occupation: the challenges of treating a symptomatic tarlov cyst.

Tarlov (perineural) cysts are meningeal dilations of the posterior spinal nerve root sheath located in between the peri- and endoneurium. We present a patient with a symptomatic sacral Tarlov cyst and the technical challenges faced by surgically treating the lesion by disconnection of the cyst from the subarachnoid space.

A combined dual-port endoscope-assisted pre- and retrosigmoid approach to the cerebellopontine angle: an extensive anatomo-surgical study.

The use of the endoscope in the cerebellopontine angle (CPA) has been suggested to minimize cerebellar retraction and reduce the size of the craniotomy. 3D endoscopy combines the benefits of conventional 2D endoscopy with the added benefit of stereoscopic perception, though improved visualization alone does not guarantee improved surgical maneuverability and a better surgical outcome. We propose a new combined dual-port endoscope-assisted pre- and retrosigmoid approach to improve visualization and accessibility of the CPA with shortened distances and increased surgical maneuverability of neurovascular structures. We analyze surgical exposure and maneuverability of this approach and compare it with the surgical microscopic and a conventional single-port endoscope-assisted retrosigmoid approach. This combined pre- and retrosigmoid approach was performed on eight cadaveric heads (16 sides). The endoscopic probe was inserted through the presigmoid surgical port while surgical manipulation was performed through the retrosigmoid corridor. The CPA was divided into three compartments, from medial to lateral, the anteromedial, and the middle and the posterolateral. The microscope provided good visualization of the posterolateral and middle compartments, whereas poor visualization was offered of the anteromedial compartment. The dual-port endoscopic approach dramatically improved visualization and surgical maneuverability of the anteromedial compartments, clivus, and related neurovascular structures. Additionally, the 3D endoscope allowed for a better understanding of the surgical anatomy of the CPA and improved visualization of structures located in the anteromedial compartments towards the midline. This approach allowed for full realization of the benefits of endoscopic-assisted technique by improving surgical access and maneuverability.

Management of post blood patch severe rebound intracranial hypertension by the usage of an external ventricular drain.

Spontaneous intracranial hypotension (SIH) is a condition characterised by postural headaches due to low cerebrospinal fluid (CSF) pressure, often stemming from CSF leakage. Diagnosis poses a significant challenge, and the therapeutic approach encompasses both conservative measures and operative interventions, such as the epidural blood patch (EBP). However, EBP carries the potential risk of inducing rebound intracranial hypertension (RIH), subsequently leading to high-pressure headaches. We present a case wherein RIH following EBP was effectively managed through the implementation of an external ventricular drain (EVD) aimed at reducing CSF pressure. The patient improved significantly, underscoring the potential utility, if not necessity, of EVD in carefully selected cases, highlighting the imperative for further research to enhance the management of SIH and optimise EBP-related complications.

Implementation of Robotic Exoscope in Minimally Invasive Corpectomy at Thoracolumbar Junction for the Treatment of Traumatic Spinal Cord Compression.

The development and diffusion of minimally invasive (MI) approaches have coincided with improvements in magnification systems. The exoscope will probably open a new era in new technologies in spinal surgery. This study reports a retrospective series of 19 thoracolumbar (T11-L2) burst fractures with anterior column failure and cord compression, treated with MI corpectomy and spinal decompression assisted by a three-dimensional high-definition exoscope (Video 1). Exclusion criteria were pathologic or osteoporotic fractures, multilevel fractures, and previous surgery at the site of the fracture. Three key indicators were recorded: surgical time, blood loss, and intraoperative complications. A questionnaire was administered to assess the users' exoscope experience with ergonomics, preparation, magnification, image definition, illumination, and user-friendliness, compared with the operative microscope. To the best of our knowledge, this is the first study reporting on exoscope-assisted MI corpectomy. This procedure permitted low blood loss and less surgical time without intraoperative complications. The exoscope offers clear advantages in terms of ergonomics, definition, and user-friendliness. Moreover, it is a suitable instrument for training and education, providing an opportunity for better interaction with other members of the surgical staff.

Reoperation in Chiari-1 Malformations.

(1) Background: The issue of unsuccessful surgery for Chiari-1 malformation (CM-1), as well as its potential causes and possible solutions, remains poorly documented and studied. (2) Methods: From a retrospective review of a personal series of 98 patients undergoing treatment for CM-1 during the past 10 years, we created two study groups. Group 1: 8 patients (8.1%) requiring additional surgeries owing to postoperative complications (7 cerebrospinal fluid leakage, 1 extradural hematoma); 7 patients (7.1%) undergoing reoperations for failed decompression during the follow-up. Group 2: During the same period, we also managed 19 patients who had previously been operated on elsewhere: 8 patients who required adequate CM-1 treatment following extradural section of the filum terminale; 11 patients requiring reoperations for failed decompression. Failed decompression was managed by adequate osteodural decompression, which was associated with tonsillectomy (6 cases), subarachnoid exploration (8 cases), graft substitution (6 cases), and occipito-cervical fixation/revision (1 case). (3) Results: There was no mortality or surgical morbidity in Group 1. However, one patient's condition worsened due to untreatable syrinx. In Group 2, there were two cases of mortality, and surgical morbidity was represented by functional limitation and pain in the patient who needed revision of the occipitocervical fixation. Twenty patients improved (58.8%), 6 remained unchanged (32.3%), 1 worsened (2.9%) and 2 died (5.9%). (4) Conclusions: The rate of complications remains high in CM-1 treatment. Unfortunately, a certain rate of treatment failure is unavoidable, but it appears that a significant number of re-operations could have been avoided using proper indications and careful technique.

Integrated spine trauma team protocol: Combined neurosurgical and orthopedic experience for the management of traumatic spinal injuries.

Objectives: During the last decades, spine surgery has grown exponentially. In spite of that, it remains a surgical specialty without a well-defined own certification. It is usually carried out, separately, by neurosurgeons and orthopedic surgeons, even if there is an overlapping of competence and skills. Materials and Methods: In our hospital, from January 2019, a systematic protocol called integrated spine trauma team protocol (ISTTP) was implemented to improve the management of traumatic spinal injuries in a multidisciplinary way. It is characterized by a specific algorithm from diagnosis to postoperative care. According to the new protocol, orthopedic spinal surgeons and neurosurgeons work together as an integrated spine trauma team. The authors analyzed, retrospectively, the results obtained by comparing patients treated before and after the application of the ISTTP. Results: The new protocol allowed a statistically significant reduction in waiting time before surgery and complication rate. Moreover, early discharge of patients was recorded. To the best of our knowledge, this is the first study that described a specific algorithm for a standardized multidisciplinary management of the spinal trauma with combined orthopedic and neurosurgeon expertise. Conclusion: Our preliminary results suggest that the application of our ISTTP leads to better results for treating traumatic spinal injury (TSI).

Relationship between lumbar lordosis, pelvic parameters, PI-LL mismatch and outcome after short fusion surgery for lumbar degenerative disease. Literature review, rational and presentation of public study protocol: RELApSE study (registry for evaluation of lumbar artrodesis sagittal alignEment).

Background: Vertebral arthrodesis for degenerative pathology of the lumbar spine still remains burdened by clinical problems with significant negative results. The introduction of the sagittal balance assessment with the evaluation of the meaning of pelvic parameters and spinopelvic (PI-LL) mismatch offered new evaluation criteria for this widespread pathology, but there is a lack of consistent evidence on long-term outcome. Methods: The authors performed an extensive systematic review of literature, with the aim to identify all potentially relevant studies about the role and usefulness of the restoration or the assessment of Sagittal balance in lumbar degenerative disease. They present the study protocol RELApSE (NCT05448092 ID) and discuss the rationale through a comprehensive literature review. Results: From the 237 papers on this topic, a total of 176 articles were selected in this review. The analysis of these literature data shows sparse and variable evidence. There are no observations or guidelines about the value of lordosis restoration or PI-LL mismatch. Most of the works in the literature are retrospective, monocentric, based on small populations, and often address the topic evaluation partially. Conclusions: The RELApSE study is based on the possibility of comparing a heterogeneous population by pathology and different surgical technical options on some homogeneous clinical and anatomic-radiological measures aiming to understanding the value that global lumbar and segmental lordosis, distribution of lordosis, pelvic tilt, and PI-LL mismatch may have on clinical outcome in lumbar degenerative pathology and on the occurrence of adjacent segment disease.

Osilodrostat in Cushing's disease: the management of its efficacy and the pitfalls of post-surgical results.

Summary: Osilodrostat is a novel, orally administered cortisol synthesis inhibitor, approved in 2020 by the European Medicines Agency (EMA) for the treatment of Cushing's syndrome in adults. A significant amount of the studies currently available in the literature focus on treatment in patients with Cushing's disease. However, data collected from patients treated with osilodrostat in real-life settings still represents a small entity. For this reason, in this article, we will discuss two real-life cases of patients with Cushing's disease treated with this drug. The first report is about a 35-year-old woman with an adrenocorticotrophic hormone (ACTH)-secreting adenoma. After non-curative trans-nasal-sphenoidal (TNS) surgery, due to a small remnant of the adenoma, medical therapy with osilodrostat achieved fast and effective biochemical and clinical response. During treatment, progressive increase of ACTH levels and an enlargement of the pituitary remnant were documented, with planned radiosurgical treatment. The second case reports a 32-year-old man diagnosed with Cushing's disease in 2020, who, after surgery refusal, started osilodrostat at progressively up-titrated doses, according to 24 h urinary free cortisol levels, up to 5 mg twice a day. With osilodrostat, the patient reached biochemical and clinical control of disease until TNS surgery in October 2021, with complete remission. The first post-surgical biochemical assessment was equivocal in spite of a transient clinical hypoadrenalism, reverted after 2 months with the restoration of physiological hypothalamic-pituitary-adrenal axis (HPA) function. Learning points: Osilodrostat is a potent oral drug viable for Cushing's disease as medical therapy when surgery is not feasible or remission cannot be reached. Osilodrostat proves to be a safe drug and its main adverse effect is hypoadrenalism, due to the adrenolytic action of the compound. Osilodrostat needs a very tailored approach in its clinical use because there is no correlation between the level of hypercortisolism pre-treatment and the dose required to reach disease control.

The Use of Intraventricular Instillation of Vancomycin to Prevent External Ventricular Drainage Related Infection: A Clinical Prospective Study.

BACKGROUND: External ventricular drainage (EVD)-related infection (ERI) represents an important condition with potential high morbidity with significant impact on patient outcomes. Prophylactic systemic antibiotics are routinely administered to patients with EVD, but they do not significantly lower the incidence of ERIs. Intraventricular treatment with vancomycin appeared to be safe and effective, but most reports are case-reports/-series and retrospective studies. METHODS: A prospective non-randomized case-control study was conducted in a consecutive series of 116 patients treated with EVD insertion. The study includes the group of patients treated with intrathecal vancomycin (Group A, 62 patients) compared with the control group treated with daily intravenous cefazolin (Group B, 54 patients). RESULTS: No statistically significant differences were found between the 2 groups with regard to the duration of catheterization and occurrence of ERI during hospitalization. EVD was replaced in 16 cases (25.8%) in group A and in 12 cases (22.2%) in the control group B (P 0.67). Three cases (4.8%) of ERI have been found in group A and 5 (9.3%) in the control group (P = 0.34). All reported cases of infection in group A were caused by gram-negative agents; on the opposite, cases of infections in the control group B were caused above all by gram-positive bacteria with a statistical difference (P = 0.03). CONCLUSIONS: In this first prospective study on this topic, we found that intrathecal Vancomycin administration in EVDs does not reduce the occurrence of ERI compared with intravenous cefazolin prophylaxis, but induces selection of gram-negative bacteria.

A minimally invasive approach for giant middle cerebral artery thrombosed aneurysms treatment.

BACKGROUND: Management of complex thrombosed aneurysms of the middle cerebral artery (MCA) is challenging. Lesions not amenable to endovascular techniques or direct clipping might require a bypass procedure with subsequent aneurysm occlusion. Various bypass techniques followed by surgical or endovascular closure of the aneurysm are available, but an unpredictable extension of the thrombus to the parent vessel and/or to perforator vessels can occur. We presented a multidisciplinary technique with the aim to reduce invasiveness and complications. METHODS: We present two patients, harboring a thrombosed giant MCA bifurcation aneurysm, who were treated with a minimally invasive three-steps multimodality procedure. In both cases, through a limited exposure of the sylvian fissure, a side-to-side anastomosis between the two M2 branches was performed, followed in the immediate postop by an endovascular occlusion of the frontal M2 branch, with the aim of transforming a bifurcation aneurysm in a sidewall aneurysm, that was then treated a few days later by flow diverter deployment. RESULTS: Both patients had excellent outcomes and were discharged after 7 days without neurological deficits. CONCLUSIONS: Treatment of complex thrombosed MCA aneurysms is challenging. Side-to-side M2 anastomosis with the aim of transforming a bifurcation aneurysm in a sidewall aneurysm, suitable to be treated few days later by flow diverter deployment, offers a minimally invasive multimodal approach with the possibility of reducing serious complications.

Holmes tremor: a delayed complication after resection of brainstem cavernomas.

OBJECTIVE: In this paper, the authors aimed to illustrate how Holmes tremor (HT) can occur as a delayed complication after brainstem cavernoma resection despite strict adherence to the safe entry zones (SEZs). METHODS: After operating on 2 patients with brainstem cavernoma at the Great Metropolitan Hospital Niguarda in Milan and noticing a similar pathological pattern postoperatively, the authors asked 10 different neurosurgery centers around the world to identify similar cases, and a total of 20 were gathered from among 1274 cases of brainstem cavernomas. They evaluated the tremor, cavernoma location, surgical approach, and SEZ for every case. For the 2 cases at their center, they also performed electromyographic and accelerometric recordings of the tremor and evaluated the post-operative tractographic representation of the neuronal pathways involved in the tremorigenesis. After gathering data on all 1274 brainstem cavernomas, they performed a statistical analysis to determine if the location of the cavernoma is a potential predicting factor for the onset of HT. RESULTS: From the analysis of all 20 cases with HT, it emerged that this highly debilitating tremor can occur as a delayed complication in patients whose postoperative clinical course has been excellent and in whom surgical access has strictly adhered to the SEZs. Three of the patients were subsequently effectively treated with deep brain stimulation (DBS), which resulted in complete or almost complete tremor regression. From the statistical analysis of all 1274 brainstem cavernomas, it was determined that a cavernoma location in the midbrain was significantly associated with the onset of HT (p < 0.0005). CONCLUSIONS: Despite strict adherence to SEZs, the use of intraoperative neurophysiological monitoring, and the immediate success of a resective surgery, HT, a severe neurological disorder, can occur as a delayed complication after resection of brainstem cavernomas. A cavernoma location in the midbrain is a significant predictive factor for the onset of HT. Further anatomical and neurophysiological studies will be necessary to find clues to prevent this complication.

Strokectomy and Extensive Cisternal CSF Drain for Acute Management of Malignant Middle Cerebral Artery Infarction: Technical Note and Case Series.

Background and Purpose: Ischemic stroke is a major cause of death and disability worldwide. Large MCA stroke may evolve as malignant space occupying lesion and mortality rate reaches 80% despite maximal medical therapy. Early decompressive craniectomy is effective in reducing mortality and improving the functional outcome but is an extended and invasive surgical approach burdened with a significant complication rate. We report a surgical treatment based on partial strokectomy and basal cisterns opening with massive CSF drain. Materials and Methods: We retrospectively collected 15 cases of massive middle cerebral artery stroke treated with strokectomy between 2010 and 2017: nine males and six females, mean age 61.73 ± 9.5 years. The right side was affected in 66.7%. All patients show clinical deterioration despite standard medical therapy and indication for surgery was placed after collegiate evaluation by neurologists and neurosurgeons based on clinical and radiological data. Results: Surgical procedure was performed 24-96 h after the stroke onset. All the 15 patients survived the intervention, one patient died 20 days after the admission for massive lung embolism. Mean GCS and NIHSS at admission were 12.6 ± 1.18 (range 9-15) and 19.7 ± 2.3 (range 18-23), respectively. Mean mRS at 12 months was 3.6 ± 1.1 (range 2-6). Mean follow-up was 18.1 months (range 12-34). The outcome was evaluated as satisfactory (mRs ≤ 3) in 8 patients (53.3%). Mortality at 1 year was 6.7%. No patients developed hydrocephalus and 1 presented seizures. According to mRs outcome evaluation (mRs ≤ 3 vs. mRs ≥ 4) no quantitative variable resulted significantly different between the two groups, whereas the concomitant use of iv rTPA significantly differed (P < 0.05). Conclusion: Supratentorial strokectomy seems to be safe and could be a potential alternative to decompressive craniectomy for the acute management of malignant MCA stroke. Advantages of this approach could be low complication rate, avoidance of bone reconstruction procedure, and reduced occurrence of hydrocephalus or seizures. A co-operative multicentric, prospective pilot study will be necessary to validate this technical approach.

Nurturing the Next Generation of Neurosurgeons: How Important Are Nontechnical Skills?

BACKGROUND: A recent trend has occurred of increased awareness and an emphasis for teaching nontechnical skills (NTSs) in the world of surgery. Although neurosurgery has incorporated simulation-based training as a part of the training curriculum in the United Kingdom, it has yet to formally introduce NTS training. The present study, therefore, queried both neurosurgical trainees and tutors regarding how much they valued NTSs and their development. METHODS: We performed a questionnaire-based, mixed-methods study to determine the knowledge, attitudes, and practices of both neurosurgical trainees and tutors regarding NTSs across neurosurgical centers in the United Kingdom in 2015. RESULTS: The trainees valued NTSs and their development more than did their tutor counterparts (P < 0.05, z-testing). This was evident from both the quantitative results and the qualitative data gained from the questionnaire. Various areas for potential improvement of the curriculum were also identified. CONCLUSION: The results of the present study highlight the importance of NTS development in neurosurgery. These results could act as a good starting point for further larger scale similar studies and discussion on curriculum committees.

Contemporary tools in arteriovenous malformations surgery.

Arteriovenous malformations (AVMs) are rare entities and therefore considered the main challenge for a neurosurgeon. Since the publication of the ARUBA study, one of the most popular debate regards the actual surgical indication for unruptured AVMs. Our group recently published a multicenter review of more than 500 cases underlying the important role of surgery. Over the last few decades, the expanding technologies used in the treatment of AVMs have shown an ongoing improvement overcoming some of the existing difficulties and shortcomings. In this paper, we reviewed the present literature to illustrate the main contemporary tools that, in our opinion, are crucial to obtain the best surgical and clinical outcome. Indocyanin green is nowadays considered a gold standard to identify arterial feeders, draining veins, and to detect any eventual residual. The use of non-stick, bipolar, 2-mm blade microclips, and thulium laser allows to obtain a better bleeding control and nidus removal. The development of the intraoperative ultrasound with neuronavigation, angiosonography, and color-Doppler improves the accuracy of AVM resection. Moreover, improvements have been developed with the use of intraoperative micro-Dopplers combined with flow measurements, which consent to verify the gradual reduction of flow through draining veins. The possibility to perform functional preoperative studies and intraoperative monitoring can be considered as an essential point in the decision making in eloquent or near-eloquent AVMs. Furthermore, the hybrid operating room represents the best expression of an excellent neurovascular team where the use of the intraoperative angiography allows neurosurgeons and neurointerventional radiologists to work at the same time in a combined approach to achieve the best surgical removal.