How to avoid intraoperative complications of active paragangliomas?

Background: Paragangliomas (PGs) are very rare neuroendocrine tumors that can be found in unusual locations such as the spinal canal. Some PGs may be endocrinologically active, containing neurotransmitters such as noradrenaline, adrenaline, and serotonin. This can lead to unexpected neurotransmitter release during the removal of PGs, leading to a hypertensive crisis. Case Description: We present two patients who underwent surgical removal of a secretory filum terminale PG. Conclusion: If laboratory tests are suggestive of a secretory tumor, surgery should include anesthesiologic preparation similar to cases of pheochromocytoma.

Complications of deep brain stimulation in Parkinson's disease: a single-center experience of 517 consecutive cases.

BACKGROUND: The number of deep brain stimulation (DBS) procedures is rapidly rising as well as the novel indications. Reporting adverse events related to surgery and to the hardware used is essential to define the risk-to-benefit ratio and develop novel strategies to improve it. OBJECTIVE: To analyze DBS complications (both procedure-related and hardware-related) and further assess potential predictive factors. METHODS: Five hundred seventeen cases of DBS for Parkinson's disease were performed between 2006 and 2021 in a single center (mean follow-up: 4.68 ± 2.86 years). Spearman's Rho coefficient was calculated to search for a correlation between the occurrence of intracerebral hemorrhage (ICH) and the number of recording tracks. Multiple logistic regression analyzed the probability of developing seizures and ICH given potential risk factors. Kaplan-Meier curves were performed to analyze the cumulative proportions of hardware-related complications. RESULTS: Mortality rate was 0.2%, while permanent morbidity 0.6%. 2.5% of cases suffered from ICH which were not influenced by the number of tracks used for recordings. 3.3% reported seizures that were significantly affected by perielectrode brain edema and age. The rate of perielectrode brain edema was significantly higher for Medtronic's leads compared to Boston Scientific's (Χ2(1)= 5.927, P= 0.015). 12.2% of implants reported Hardware-related complications, the most common of which were wound revisions (7.2%). Internal pulse generator models with smaller profiles displayed more favorable hardware-related complication survival curves compared to larger designs (X2(1)= 8.139, P= 0.004). CONCLUSION: Overall DBS has to be considered a safe procedure, but future research is needed to decrease the rate of hardware-related complications which may be related to both the surgical technique and to the specific hardware's design. The increased incidence of perielectrode brain edema associated with certain lead models may likewise deserve future investigation.

MER and increased operative time are not risk factors for the formation of pneumocephalus during DBS.

Although only recently directional leads have proven their potential to compensate for sub-optimally placed electrodes, optimal lead positioning remains the most critical factor in determining Deep Brain Stimulation (DBS) outcome. Pneumocephalus is a recognized source of error, but the factors that contribute to its formation are still a matter of debate. Among these, operative time is one of the most controversial. Because cases of DBS performed with Microelectrode Recordings (MER) are affected by an increase in surgical length, it is useful to analyze whether MER places patients at risk for increased intracranial air entry. Data of 94 patients from two different institutes who underwent DBS for different neurologic and psychiatric conditions were analyzed for the presence of postoperative pneumocephalus. Operative time and use of MER, as well as other potential risk factors for pneumocephalus (age, awake vs. asleep surgery, number of MER passages, burr hole size, target and unilateral vs. bilateral implants) were examined. Mann-Whitney U and Kruskal-Wallis tests were utilized to compare intracranial air distributions across groups of categorical variables. Partial correlations were used to assess the association between time and volume. A generalized linear model was created to predict the effects of time and MER on the volume of intracranial air, controlling for other potential risk factors identified: age, number of MER passages, awake vs. asleep surgery, burr hole size, target, unilateral vs. bilateral surgery. Significantly different distributions of air volume were noted between different targets, unilateral vs. bilateral implants, and number of MER trajectories. Patients undergoing DBS with MER did not present a significant increase in pneumocephalus compared to patients operated without (p = 0.067). No significant correlation was found between pneumocephalus and time. Using multivariate analysis, unilateral implants exhibited lower volumes of pneumocephalus (p = 0.002). Two specific targets exhibited significantly different volumes of pneumocephalus: the bed nucleus of the stria terminalis with lower volumes (p < 0.001) and the posterior hypothalamus with higher volumes (p = 0.011). MER, time, and other parameters analyzed failed to reach statistical significance. Operative time and use of intraoperative MER are not significant predictors of pneumocephalus during DBS. Air entry is greater for bilateral surgeries and may be also influenced by the specific stimulated target.

Fluorescein sodium-guided resection of a cerebellar lymphoma: case report and literature review.

We report on a patient, who underwent the resection of a cerebellar primary central nervous system lymphoma and was administered intraoperative fluorescein sodium to improve the visualization of the tumor and guide surgery. Low-dosage fluorescein was administered prior to opening the dura so to distinguish contrast-enhanced lymphomatous tissue from the surrounding unenhanced brain cerebellar parenchyma. Intraoperatively, the tumor was indistinguishable from cerebellar parenchyma under the white light, however, after the administration of low-dose intravenous fluorescein, it appeared brightly fluorescent under yellow light, and was safely resected. Our protocol of administration allowed for the sampling of the pathological tissue while at the same time avoiding neurological damage. The fluorescein-guided technique for the resection of primary central nervous system lymphomas has only been rarely described, as surgical excision of such tumors is rarely indicated. Starting from our case, we review and discuss the pertinent literature. Furthermore, an intraoperative video detail is provided.

Deep brain stimulation for Parkinson's disease in practice: results of the survey by the Italian Neurosurgery Society.

BACKGROUND: Deep brain stimulation (DBS) is a safe and effective treatment for patients with advanced Parkinson's disease (PD) and many neurosurgical centers in Italy have a DBS program. Considering the prevalence of PD and criteria for DBS implantation, about 3200-10,350 PD patients may benefit from DBS in Italy. The global management of patients underwent DBS is complex and it can be supposed that many differences exist between centers in clinical practice. The Italian Neurosurgery Society (SINch) designed this survey to investigate the state of the art of DBS for PD in Italy. METHODS: A 26-item closed-ended question survey was designed and sanded by email at all Italian Neurosurgery centers. The main topic investigated was DBS teams, anatomical target selection, surgical procedure, neuroimaging, intraoperative target localization, DBS device and patients' follow-up. RESULTS: A total of 23 neurosurgery centers completed the survey. There are mainly low-to medium-volume centers (<20 annual DBS procedures) with dedicated DBS teams. The principal anatomical target used is subthalamic nucleus (STN) and, relative to the surgical technique, it emerges that in Italy DBS are bilaterally implanted in a single-step session with awake anesthesia and with frame-based technique. Final leads positioning is defined by microelectrode recordings (MER) and microstimulation (MS), with limited role of intraoperative neuroimaging (MRI and O-Arm). The stimulation is started at 15 or 30 days from procedure. CONCLUSIONS: Many centers of neurosurgery in Italy have a well-established DBS program for patients with advanced PD and some practical differences in technique between centers exist. Further investigation is needed to investigate specific criteria for selecting one technique over another.

A cervical solitary fibrous tumor with intramedullary invasion.

Solitary fibrous tumor is a tumor originating from the mesenchymal cells, which occurrence in the central nervous system is extremely rare and was described in few patients as to yet. We report on a 53-years old male patient presenting with right upper limb radicular pain and ipsilateral limbs paresis, who was diagnosed with a cervical spinal lesion which, after surgical resection, resulted to be a solitary fibrous tumor (SFT). We discuss imaging, clinical and histopathological findings to allow considering this tumor early in the differential diagnosis.

Pros of the contralateral (over-the-top) approach to intra/extraforaminal lumbar disc herniations at the L5-S1 level.

Background: Minimally invasive approaches to intra/extraforaminal lumbar disc herniations offer the benefit of less bone removal and reduced nerve root manipulation at the L5-S1 level. Moreover, the potential to better preserve stability. Methods: Here, we summarized the efficacy of the contralateral approach to intraforaminal/extraforaminal lumbar disc herniations particularly focusing on the L5-S1 level. Variables studied included the level of these disc herniations, their locations within the foramina, and the anatomy of the facet joints. Results: A major "pro" for the contralateral interlaminar procedure at the L5-S1 level is that it does not require facet joint removal, or with a spondylotic facet, <30% joint excision, to directly visualize the intraforaminal/ extraforaminal nerve root. It, therefore, reduces the risk of creating iatrogenic instability, while offering a higher certitude of adequate nerve root visualization, decompression, and safer disc removal. Conclusion: The contralateral interlaminar approach is more suitable for all types of intra/extraforaminal disc herniations at the L5/S1 level. The most specific benefit of this approach is its avoidance of disruption/significant removal (i.e., <30%) of the facet joint to adequately expose the foraminal L5 nerve root, and more safely remove the intra/extraforaminal disc herniation.

Intraoperative mobile computed tomography in deep brain stimulation: Comparison between Airo CT and O-arm CT.

Background: A new intraoperative mobile device, called Airo computed tomography (CT), is becoming increasingly used in surgery adding to the current most widespread intraoperative imaging in form of the O-arm CT device. Intraoperative CT imaging has the advantage to reduce the discomfort derived from the patient's transfer from the operative room to the radiological unit and also the time of control or time of reposition in cases of lead misplacement. This is the first rapport on Airo CT device application in DBS surgery. Methods: In our retrospective study, we have evaluated 52 patients who had DBS from October 2020 to November 2021. All patients underwent a preoperative brain magnetic resonance imaging (MRI) and a stereotactic brain CT scan. We performed an intraoperative CT scan with the Airo device. Images were subsequently transferred to the neuronavigation system (BrainLab cranial software) and merged with preoperative planning images to confirm correct position of leads. Five aspects were compared: patient and surgeon comfort, surgical planning, parenchymal visualization, radioscopic lead visualization, and costs. Results: Both imaging devices are easy-to-use, precise, and safe and have their pros and cons. Conclusion: This is the first study reporting on CT-Airo application in DBS. We advise that if only DBS is considered, the O-arm application might be more suitable. If in addition to DBS cranial surgery is performed, the Airo device is more suitable.

Thalamic Local Field Potentials Are Related to Long-Term DBS Effects in Tourette Syndrome.

Background: Local field potential (LFP) recordings helped to clarify the pathophysiology of Tourette syndrome (TS) and to define new strategies for deep brain stimulation (DBS) treatment for refractory TS, based on the delivery of stimulation in accordance with changes in the electrical activity of the DBS target area. However, there is little evidence on the relationship between LFP pattern and DBS outcomes in TS. Objective: To investigate the relationship between LFP oscillations and DBS effects on tics and on obsessive compulsive behavior (OCB) comorbidities. Methods: We retrospectively analyzed clinical data and LFP recordings from 17 patients treated with DBS of the centromedian-parafascicular/ventralis oralis (CM-Pf/VO) complex, and followed for more several years after DBS in the treating center. In these patients, LFPs were recorded either in the acute setting (3-5 days after DBS electrode implant) or in the chronic setting (during impulse generator replacement surgery). LFP oscillations were correlated with the Yale Global Tic Severity Scale (YGTSS) and the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) collected at baseline (before DBS surgery), 1 year after DBS, and at the last follow-up available. Results: We found that, at baseline, in the acute setting, the power of the oscillations included in the 5-15-Hz band, previously identified as TS biomarker, is correlated with the pathophysiology of tics, being significantly correlated with total YGTSS before DBS (Spearman's ρ = 0.701, p = 0.011). The power in the 5-15-Hz band was also correlated with the improvement in Y-BOCS after 1 year of DBS (Spearman's ρ = -0.587, p = 0.045), thus suggesting a relationship with the DBS effects on OCB comorbidities. Conclusions: Our observations confirm that the low-frequency (5-15-Hz) band is a significant biomarker of TS, being related to the severity of tics and, also to the long-term response on OCBs. This represents a step toward both the understanding of the mechanisms underlying DBS effects in TS and the development of adaptive DBS strategies.

Anterior cervical spine surgical complications: Safety comparison between teacher and student.

BACKGROUND: Anterior cervical surgery has a widespread use. Despite its popularity, this surgery can lead to serious and life-threatening complications, and warrants the attention of skilled attending spinal surgeons with many years of experience. METHODS: We retrospectively evaluated postoperative complications occurring in 110 patients who underwent anterior cervical surgery (anterior cervical discectomy without fusion, anterior cervical discectomy and fusion, and anterior cervical disc arthroplasty) between 2013 and 2020. These operations were performed by an either an attending surgeon with 30 years' experience versus a novice neurosurgeon (NN) with <5 years of training with the former surgeon. Complications were variously identified utilizing admission/discharge notes, surgical reports, follow-up visits, and phone calls. Complications for the two groups were compared for total and specific complication rates (using the Pearson's Chi-square and Fisher's test). RESULTS: The total cumulative complication rate was 15.4% and was not significantly different between the two cohorts. The most frequent postoperative complication was dysphagia. Notably, there were no significant differences in total number of postoperative instances of dysphagia, dysphonia, unintended durotomy, hypoasthenia, and hypoesthesia; the only difference was the longer operative times for NNs. CONCLUSION: Surgeons' years of experience proved not to be a critical factor in determining complication rates following anterior cervical surgery.

Cervical Spondylotic Myelopathy with Ossification of Posterior Longitudinal Ligament: Which Is the Most Suitable Surgical Procedure? A Technical Note.

INTRODUCTION: Anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) are widely performed to resolve anterior cervical spine compression. The main purpose of the different surgical techniques is to obtain an adequate decompression of the spinal cord and nerve roots, preserving spinal stability like in oblique corpectomy or leading to a final solid construct to achieve arthrodesis. TECHNICAL NOTE: We describe a surgical procedure for treating cervical spondylotic myelopathy(CSM) with ossification of the posterior longitudinal ligament (OPLL) at the level of C3-C4 and C4-C5. A double level discectomy C3-C4 and C4-C5 and selective posterior wedge corpectomy of C3, C4, and C5 were performed. Two cages (Zero-P VA) at C3-C4 and C4-C5 were positioned to obtain segmental stability and arthrodesis. An extended anterior cervical canal decompression was obtained and confirmed by postsurgical CT scan. At 15 months, dynamic X-ray showed fusion, and cervical magnetic resonance imaging (MRI) showed evidence of spinal canal decompression. CONCLUSIONS: Anterior cervical discectomy followed by selective wedge corpectomy appears to be a safe and effective technique for anterior spinal cord compression extending above and below the intervertebral disc space.

Tailored therapy: Surgical and radiosurgical treatment for two distinct myxopapillary ependymomas in the same patient. A case report.

Myxopapillary ependymomas are low grade neoplasms, which originate mostly from the medullary conus, cauda equina and the filum terminale. To date the principal treatment is surgical, total- or subtotal removal (GTR or STR), which can be associated with adjuvant radiotherapy. We report a patient with two tumor locations, one larger tumor at the L3 to S1 level and a smaller S2-S3 localized lesion. The patient was treated successfully with a combined approach of GTR of L3-S1 lesion and radiosurgical treatment of S2-S3 lesion.

Changes in eating behavior after deep brain stimulation for anorexia nervosa. A case study.

PURPOSE: The purpose of this study was to evaluate changes in the nutritional status, body image concerns, and eating behaviors occurring in a patient who underwent deep brain stimulation (DBS) of the bed nucleus of the stria terminalis for treatment-refractory anorexia nervosa (AN). METHODS: Bilateral DBS of the bed nucleus of the stria terminalis was performed in a 37-year-old woman affected by refractory AN. Pre- and post-surgical evaluations were conducted via an array of validated testing instruments, which took into account the weight variations, body image concerns, eating behavior, quality of life, and nutritional status. RESULTS: Overall, eating behavior-, body image concern-, and nutritional status-related testing instruments demonstrated improvements starting from the first post-operative month. Normal body weight was restored after 4 months of stimulation. DISCUSSION: Only a few cases of DBS for AN have been conducted to determine the efficacy of surgery based upon weight variation and psychometric scales for anxiety and affective disorders. In contrast, we have designed a comprehensive approach taking into account the most important aspects of this disease. This approach should be considered in future studies dealing with the neurosurgical treatment of AN.

Ablative brain surgery: an overview.

Background: Ablative therapies have been used for the treatment of neurological disorders for many years. They have been used both for creating therapeutic lesions within dysfunctional brain circuits and to destroy intracranial tumors and space-occupying masses. Despite the introduction of new effective drugs and neuromodulative techniques, which became more popular and subsequently caused brain ablation techniques to fall out favor, recent technological advances have led to the resurgence of lesioning with an improved safety profile. Currently, the four main ablative techniques that are used for ablative brain surgery are radiofrequency thermoablation, stereotactic radiosurgery, laser interstitial thermal therapy and magnetic resonance-guided focused ultrasound thermal ablation. Object: To review the physical principles underlying brain ablative therapies and to describe their use for neurological disorders. Methods: The literature regarding the neurosurgical applications of brain ablative therapies has been reviewed. Results: Ablative treatments have been used for several neurological disorders, including movement disorders, psychiatric disorders, chronic pain, drug-resistant epilepsy and brain tumors. Conclusions: There are several ongoing efforts to use novel ablative therapies directed towards the brain. The recent development of techniques that allow for precise targeting, accurate delivery of thermal doses and real-time visualization of induced tissue damage during the procedure have resulted in novel techniques for cerebral ablation such as magnetic resonance-guided focused ultrasound or laser interstitial thermal therapy. However, older techniques such as radiofrequency thermal ablation or stereotactic radiosurgery still have a pivotal role in the management of a variety of neurological disorders.

Pisa syndrome in Idiopathic Normal Pressure Hydrocephalus.

INTRODUCTION: Idiopathic Normal Pressure Hydrocephalus (iNPH) is a complex syndrome of ventriculomegaly that can include parkinsonian-like features besides the classical triad of cognitive decline, urinary incontinence, and gait/balance disturbances. Pisa syndrome (PS) is a postural abnormality often associated with parkinsonism and defined as lateral trunk flexion greater than 10° while standing that resolves in the supine position. We reported a case series of classical "fixed" PS and one case of "Metronome" recurrent side-alternating PS in iNPH, displaying opposite electromyographic patterns of paraspinal muscles. METHODS: Eighty-five iNPH patients were followed longitudinally for at least one year through scheduled clinical and neuropsychological visits. RESULTS: Five (5.9%) subjects revealed PS. None of them had nigrostriatal dopaminergic involvement detected by [123I]FP-CIT SPECT. Among these patients, four had "fixed" PS, whereas one showed a recurrent side-alternating PS which repeatedly improved after ventriculo-peritoneal shunt and following adjustments of the valve-opening pressure of the shunt system. DISCUSSION: This is the first case series of PS in iNPH and the first report of "Metronome" PS in iNPH. The prompt response of the abnormal trunk postures through cerebrospinal fluid (CSF) shunt surgery suggests a causative role of an altered CSF dynamics. PS and gait disorders in iNPH could be explained by a direct involvement of cortico-subcortical pathways and subsequent secondary brainstem involvement, with also a possible direct functional damage of the basal ganglia at the postsynaptic level, due to enlargement of the ventricular system and impaired CSF dynamics. The early detection of these cases supports a proper surgical management.

Is Transposition of Deep Brain Stimulation Device a Solution in Patients with Recurrent Skin Erosions?

Skin erosion and infection are common but serious problems in deep brain stimulation (DBS). They can lead to the removal of the entire DBS device and consequently stop the entire treatment. Of critical importance, therefore, is to find surgical solutions that allow to leave the complex DBS device in place when medical treatment fails in repeated skin complications, to allow continuing treatment in otherwise pharmacological refractory patients. We present a patient with repeated retro-auricular skin erosions, who failed to respond to surgical revisions and antibiotic treatment. However, instead of removing the DBS device as it would be general practice we succeeded with a right to left transposition of connecting cables to save the entire DBS system. There is lack of data on therapeutic surgical options in repeated skin complications. We propose the transposition of DBS device as possible solution for multiple skin erosions in DBS surgery.

Venous Infarct after Sacrifice of Single Cortical Vein during Deep-Brain Stimulation Surgery.

Intracerebral hemorrhage (ICH) is the most feared and dreadful complication related to deep-brain stimulation (DBS). Bleeding may originate from arterial or venous damage. Commonly, hemorrhage is detected by postoperative imaging performed to assess lead positioning in asymptomatic patients. Rarely, hemorrhage leads to stroke, coma, or even death. We present the case of a patient who suffered a severe ICH of venous origins after bilateral DBS. Deep-brain hemorrhages are the most difficult to be predicted and to be prevented because they are caused by small vessels. As superficial hemorrhages are secondary to venous coagulation or sulcal hemorrhage, neurosurgeons must drive all efforts to minimize their occurrence.

Efficacy and Safety of Deep Brain Stimulation in Tourette Syndrome: The International Tourette Syndrome Deep Brain Stimulation Public Database and Registry.

Importance: Collective evidence has strongly suggested that deep brain stimulation (DBS) is a promising therapy for Tourette syndrome. Objective: To assess the efficacy and safety of DBS in a multinational cohort of patients with Tourette syndrome. Design, Setting, and Participants: The prospective International Deep Brain Stimulation Database and Registry included 185 patients with medically refractory Tourette syndrome who underwent DBS implantation from January 1, 2012, to December 31, 2016, at 31 institutions in 10 countries worldwide. Exposures: Patients with medically refractory symptoms received DBS implantation in the centromedian thalamic region (93 of 163 [57.1%]), the anterior globus pallidus internus (41 of 163 [25.2%]), the posterior globus pallidus internus (25 of 163 [15.3%]), and the anterior limb of the internal capsule (4 of 163 [2.5%]). Main Outcomes and Measures: Scores on the Yale Global Tic Severity Scale and adverse events. Results: The International Deep Brain Stimulation Database and Registry enrolled 185 patients (of 171 with available data, 37 females and 134 males; mean [SD] age at surgery, 29.1 [10.8] years [range, 13-58 years]). Symptoms of obsessive-compulsive disorder were present in 97 of 151 patients (64.2%) and 32 of 148 (21.6%) had a history of self-injurious behavior. The mean (SD) total Yale Global Tic Severity Scale score improved from 75.01 (18.36) at baseline to 41.19 (20.00) at 1 year after DBS implantation (P < .001). The mean (SD) motor tic subscore improved from 21.00 (3.72) at baseline to 12.91 (5.78) after 1 year (P < .001), and the mean (SD) phonic tic subscore improved from 16.82 (6.56) at baseline to 9.63 (6.99) at 1 year (P < .001). The overall adverse event rate was 35.4% (56 of 158 patients), with intracranial hemorrhage occurring in 2 patients (1.3%), infection in 4 patients with 5 events (3.2%), and lead explantation in 1 patient (0.6%). The most common stimulation-induced adverse effects were dysarthria (10 [6.3%]) and paresthesia (13 [8.2%]). Conclusions and Relevance: Deep brain stimulation was associated with symptomatic improvement in patients with Tourette syndrome but also with important adverse events. A publicly available website on outcomes of DBS in patients with Tourette syndrome has been provided.

Contralateral interlaminar approach for intraforaminal lumbar degenerative disease with special emphasis on L5-S1 level: A technical note.

BACKGROUND: Intraforaminal disc herniations at the L5-S1 level are extremely surgically challenging lesions. Intracanal approaches frequently require partial or total facetectomy, which may lead to instability. Solely extraforaminal approaches may offer limited visualization of the more medial superiorly exiting and inferiorly exiting nerve roots; this approach is also more complicated at L5-S1 due to the often large L5 transverse process and the iliac wing. METHODS: Nine patients with intraforaminal L5-S1 disc herniations, foraminal stenosis, or synovial cysts underwent contralateral interlaminar approaches for lesion resection. Preoperative and postoperative visual analog scale scores were evaluated, and complications were reviewed. RESULTS: All 9 patients demonstrated immediate postoperative clinical improvement. None of the patients exhibited complications and none developed instability or neuropathic disorders. CONCLUSIONS: Although the number of cases in our sample was very small (9 in total), the contralateral interlaminar approach appeared to effectively address multiple degenerative L5-S1 foraminal pathologies. Large studies are needed to further evaluate the pros and cons of this approach.