Stereotactic and Functional Neurosurgery最新文献

{"title":"Ambulatory Local Field Potential Recordings from the Thalamus in Epilepsy: A Feasibility Study.","authors":"David Satzer, Shasha Wu, Julia Henry, Emily Doll, Naoum P Issa, Peter C Warnke","doi":"10.1159/000529961","DOIUrl":"10.1159/000529961","url":null,"abstract":"<p><strong>Introduction: </strong>Stimulation of the thalamus is gaining favor in the treatment of medically refractory multifocal and generalized epilepsy. Implanted brain stimulators capable of recording ambulatory local field potentials (LFPs) have recently been introduced, but there is little information to guide their use in thalamic stimulation for epilepsy. This study sought to assess the feasibility of chronically recording ambulatory interictal LFP from the thalamus in patients with epilepsy.</p><p><strong>Methods: </strong>In this pilot study, ambulatory LFP was recorded from patients who underwent sensing-enabled deep brain stimulation (DBS, 2 participants) or responsive neurostimulation (RNS, 3 participants) targeting the anterior nucleus of the thalamus (ANT, 2 electrodes), centromedian nucleus (CM, 7 electrodes), or medial pulvinar (PuM, 1 electrode) for multifocal or generalized epilepsy. Time-domain and frequency-domain LFP was investigated for epileptiform discharges, spectral peaks, circadian variation, and peri-ictal patterns.</p><p><strong>Results: </strong>Thalamic interictal discharges were visible on ambulatory recordings from both DBS and RNS. At-home interictal frequency-domain data could be extracted from both devices. Spectral peaks were noted at 10-15 Hz in CM, 6-11 Hz in ANT, and 19-24 Hz in PuM but varied in prominence and were not visible in all electrodes. In CM, 10-15 Hz power exhibited circadian variation and was attenuated by eye opening.</p><p><strong>Conclusion: </strong>Chronic ambulatory recording of thalamic LFP is feasible. Common spectral peaks can be observed but vary between electrodes and across neural states. DBS and RNS devices provide a wealth of complementary data that have the potential to better inform thalamic stimulation for epilepsy.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11227660/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10557416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Practical Guideline for Prevention of Patchy Hair Loss following CyberKnife Stereotactic Radiosurgery for Calvarial or Scalp Tumors: Retrospective Analysis of a Single Institution Experience.","authors":"David J Park,&nbsp;Neelan J Marianayagam,&nbsp;Ulas Yener,&nbsp;Armine Tayag,&nbsp;Louisa Ustrzynski,&nbsp;Sara C Emrich,&nbsp;Erqi Pollom,&nbsp;Scott Soltys,&nbsp;Antonio Meola,&nbsp;Steven D Chang","doi":"10.1159/000533555","DOIUrl":"10.1159/000533555","url":null,"abstract":"Introduction: Patchy alopecia is a common adverse effect of stereotactic radiosurgery (SRS) on the calvarium and/or scalp, yet no guidelines exist for its prevention. This study aims to investigate the incidence and outcomes of patchy alopecia following SRS for patients with calvarial or scalp lesions and establish preventive guidelines. Methods: The study included 20 patients who underwent CyberKnife SRS for calvarial or scalp lesions, resulting in a total of 30 treated lesions. SRS was administered as a single fraction for 8 lesions and hypofractionated for 22 lesions. The median SRS target volume was 9.85 cc (range: 0.81–110.7 cc), and the median prescription dose was 27 Gy (range: 16–40 Gy), delivered in 1–5 fractions (median: 3). The median follow-up was 15 months. Results: Among the 30 treated lesions, 11 led to patchy alopecia, while 19 did not. All cases of alopecia resolved within 12 months, and no patients experienced other adverse radiation effects. Lesions resulting in alopecia exhibited significantly higher biologically effective dose (BED) and single-fraction equivalent dose (SFED) on the overlying scalp compared to those without alopecia. Patients with BED and SFED exceeding 60 Gy and 20 Gy, respectively, were 9.3 times more likely to experience patchy alopecia than those with lower doses. The 1-year local tumor control rate for the treated lesions was 93.3%. Chemotherapy was administered for 26 lesions, with 11 lesions receiving radiosensitizing agents. However, no statistically significant difference was found. Conclusion: In summary, SRS is a safe and effective treatment for patients with calvarial/scalp masses regarding patchy alopecia near the treated area. Limiting the BED under 60 Gy and SFED under 20 Gy for the overlying scalp can help prevent patchy alopecia during SRS treatment of the calvarial/scalp mass. Clinicians can use this information to inform patients about the risk of alopecia and the contributing factors.","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10214261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct Biomarkers of ANT Stimulation and Seizure Freedom in an Epilepsy Patient with Ambulatory Hippocampal Electrocorticography.","authors":"Henry M Skelton, David M Brandman, Katie Bullinger, Faical Isbaine, Robert E Gross","doi":"10.1159/000533680","DOIUrl":"10.1159/000533680","url":null,"abstract":"<p><strong>Introduction: </strong>Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) and responsive neurostimulation (RNS) of the hippocampus are the predominant approaches to brain stimulation for treating mesial temporal lobe epilepsy (MTLE). Both are similarly effective at reducing seizures in drug-resistant patients, but the underlying mechanisms are poorly understood. In rare cases where it is clinically indicated to use RNS and DBS simultaneously, ambulatory electrophysiology from RNS may provide the opportunity to measure the effects of ANT DBS in the putative seizure onset zone and identify biomarkers associated with clinical improvement. Here, one such patient became seizure free, allowing us to identify and compare the changes in hippocampal electrophysiology associated with ANT stimulation and seizure freedom.</p><p><strong>Methods: </strong>Ambulatory electrocorticography and clinical history were retrospectively analyzed for a patient treated with RNS and DBS for MTLE. DBS artifacts were used to identify ANT stimulation periods on RNS recordings and measure peri-stimulus electrographic changes. Clinical history was used to determine the chronic electrographic changes associated with seizure freedom.</p><p><strong>Results: </strong>ANT stimulation acutely suppressed hippocampal gamma (25-90Hz) power, with minimal theta (4-8Hz) suppression and without clear effects on seizure frequency. Eventually, the patient became seizure free alongside the emergence of chronic gamma increase and theta suppression, which started at the same time as clobazam was introduced. Both seizure freedom and the associated electrophysiology persisted after inadvertent DBS discontinuation, further implicating the clobazam relationship. Unexpectedly, RNS detections and long episodes increased, although they were not considered to be electrographic seizures, and the patient remained clinically seizure free.</p><p><strong>Conclusion: </strong>ANT stimulation and seizure freedom were associated with distinct, dissimilar spectral changes in RNS-derived electrophysiology. The time course of these changes supported a new medication as the most likely cause of clinical improvement. Broadly, this work showcases the use of RNS recordings to interpret the effects of multimodal therapy. Specifically, it lends additional credence to hippocampal theta suppression as a biomarker previously associated with seizure reduction in RNS patients.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41151410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying the Variability Associated with Postoperative Localization of Deep Brain Stimulation Electrodes.","authors":"Kelsey L Bower, Angela M Noecker, Martin M Reich, Cameron C McIntyre","doi":"10.1159/000530462","DOIUrl":"10.1159/000530462","url":null,"abstract":"<p><strong>Introduction: </strong>Computational models of deep brain stimulation (DBS) have become common tools in clinical research studies that attempt to establish correlations between stimulation locations in the brain and behavioral outcome measures. However, the accuracy of any patient-specific DBS model depends heavily upon accurate localization of the DBS electrodes within the anatomy, which is typically defined via co-registration of clinical CT and MRI datasets. Several different approaches exist for this challenging registration problem, and each approach will result in a slightly different electrode localization. The goal of this study was to better understand how different processing steps (e.g., cost-function masking, brain extraction, intensity remapping) affect the estimate of the DBS electrode location in the brain.</p><p><strong>Methods: </strong>No \"gold standard\" exists for this kind of analysis, as the exact location of the electrode in the living human brain cannot be determined with existing clinical imaging approaches. However, we can estimate the uncertainty associated with the electrode position, which can be used to guide statistical analyses in DBS mapping studies. Therefore, we used high-quality clinical datasets from 10 subthalamic DBS subjects and co-registered their long-term postoperative CT with their preoperative surgical targeting MRI using 9 different approaches. The distances separating all of the electrode location estimates were calculated for each subject.</p><p><strong>Results: </strong>On average, electrodes were located within a median distance of 0.57 mm (0.49-0.74) of one another across the different registration approaches. However, when considering electrode location estimates from short-term postoperative CTs, the median distance increased to 2.01 mm (1.55-2.78).</p><p><strong>Conclusions: </strong>The results of this study suggest that electrode location uncertainty needs to be factored into statistical analyses that attempt to define correlations between stimulation locations and clinical outcomes.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10833063/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10204831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intracranial Bleeding in Deep Brain Stimulation Surgery: A Systematic Review and Meta-Analysis.","authors":"Jakov Tiefenbach,&nbsp;Leonardo Favi Bocca,&nbsp;Olivia Hogue,&nbsp;Neil Nero,&nbsp;Kenneth B Baker,&nbsp;Andre G Machado","doi":"10.1159/000530398","DOIUrl":"https://doi.org/10.1159/000530398","url":null,"abstract":"<p><strong>Background: </strong>Deep brain stimulation (DBS) is a neurosurgical treatment used for the treatment of movement disorders. Surgical and perioperative complications, although infrequent, can result in clinically significant neurological impairment.</p><p><strong>Objectives: </strong>In this study, we evaluated the incidence and risk factors of intracranial bleeding in DBS surgery.</p><p><strong>Method: </strong>Medline, EMBASE, and Cochrane were screened in line with PRISMA 2020 guidelines to capture studies reporting on the incidence of hemorrhagic events in DBS. After removing duplicates, the search yielded 1,510 papers. Abstracts were evaluated by two independent reviewers for relevance. A total of 386 abstracts progressed to the full-text screen and were assessed against eligibility criteria. A total of 151 studies met the criteria and were included in the analysis. Any disagreement between the reviewers was resolved by consensus. Relevant data points were extracted and analyzed in OpenMeta [Analyst] software.</p><p><strong>Results: </strong>The incidence of intracranial bleeding was 2.5% (95% CI: 2.2-2.8%) per each patient and 1.4% (95% CI: 1.2-1.6%) per each implanted lead. There was no statistically significant difference across implantation targets and clinical indications. Patients who developed an intracranial bleed were on average 5 years older (95% CI: 1.26-13.19), but no difference was observed between the genders (p = 0.891). A nonsignificant trend was observed for a higher risk of bleeding in patients with hypertension (OR: 2.99, 95% CI: 0.97-9.19) (p = 0.056). The use of microelectrode recording did not affect the rate of bleeding (p = 0.79).</p><p><strong>Conclusions: </strong>In this review, we find that the rate of bleeding per each implanted lead was 1.4% and that older patients had a higher risk of hemorrhage.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10000186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gamma Knife Radiosurgery for SUNCT: A Case Series.","authors":"Andrea Franzini,&nbsp;Davide Milani,&nbsp;Luca Attuati,&nbsp;Pierina Navarria,&nbsp;Federico Pessina,&nbsp;Piero Picozzi","doi":"10.1159/000528632","DOIUrl":"https://doi.org/10.1159/000528632","url":null,"abstract":"<p><strong>Background: </strong>The treatment of medically refractory patients with chronic short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is challenging. Stereotactic radiosurgery targeting the trigeminal nerve and sphenopalatine ganglion (SPG) has been used as a less-invasive treatment. The outcomes of this procedure have been described in a few case reports.</p><p><strong>Objectives: </strong>The objective of the study was to report on the effect of Gamma Knife radiosurgery (GKRS) in 5 patients with chronic SUNCT.</p><p><strong>Methods: </strong>Retrospective review of our GKRS database identified 5 patients with chronic SUNCT who underwent GKRS targeted to the trigeminal nerve and SPG. A maximum dose of 80-85 Gy and 80 Gy was, respectively, delivered to the trigeminal nerve and SPG. Pain intensity and facial numbness were evaluated using the Barrow Neurological Institute (BNI) scores.</p><p><strong>Results: </strong>These 5 patients were clinically followed for a mean period of 26.2 months. Within a period ranging from 2 days to 9 months, GKRS was successful in reducing pain attacks and autonomic symptoms in all 5 patients. At the last assessments, BNI pain scores of I, II, and IIIa were achieved in 1, 1, and 3 patients, respectively. Two patients developed nonbothersome facial numbness (BNI facial numbness score II).</p><p><strong>Conclusions: </strong>These 5 cases show that GKRS targeted to both the trigeminal nerve and the SPG is effective in reducing pain and autonomic symptoms of patients with SUNCT, although nonbothersome trigeminal sensory disturbances may occur.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9267141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Choice of Implantable Pulse Generators for Deep Brain Stimulation: An Overview of Clinical Practice.","authors":"Yara Rosalie Willems,&nbsp;Niels Anthony van der Gaag,&nbsp;Kuan Hua Kho,&nbsp;Øystein Vesterli Tveiten,&nbsp;Marie Therese Krüger,&nbsp;Martin Jakobs","doi":"10.1159/000529495","DOIUrl":"https://doi.org/10.1159/000529495","url":null,"abstract":"<p><strong>Introduction: </strong>The success of deep brain stimulation (DBS) treatment depends on several factors, including proper patient selection, accurate electrode placement, and adequate stimulation settings. Another factor that may impact long-term satisfaction and therapy outcomes is the type of implantable pulse generator (IPG) used: rechargeable or non-rechargeable. However, there are currently no guidelines on the choice of IPG type. The present study investigates the current practices, opinions, and factors DBS clinicians consider when choosing an IPG for their patients.</p><p><strong>Methods: </strong>Between December 2021 and June 2022, we sent a structured questionnaire with 42 questions to DBS experts of two international, functional neurosurgery societies. The questionnaire included a rating scale where participants could rate the factors influencing their choice of IPG type and their satisfaction with certain IPG aspects. Additionally, we presented four clinical case scenarios to assess preference of choice of IPG-type in each case.</p><p><strong>Results: </strong>Eighty-seven participants from 30 different countries completed the questionnaire. The three most relevant factors for IPG choice were \"existing social support,\" \"cognitive status,\" and \"patient age.\" Most participants believed that patients valued avoiding repetitive replacement surgeries more than the burden of regularly recharging the IPG. Participants reported that they implanted the same amount of rechargeable as non-rechargeable IPGs for primary DBS insertions and 20% converted non-rechargeable to rechargeable IPGs during IPG replacements. Most participants estimated that rechargeable was the more cost-effective option.</p><p><strong>Conclusion: </strong>This present study shows that the decision-making of the choice of IPG is very individualized. We identified the key factors influencing the physician's choice of IPG. Compared to patient-centric studies, clinicians may value different aspects. Therefore, clinicians should rely not only on their opinion but also counsel patients on different types of IPGs and consider the patient's preferences. Uniform global guidelines on IPG choice may not represent regional or national differences in the healthcare systems.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9268206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hemorrhagic Safety of Magnetic Resonance-Guided Focused Ultrasound Thalamotomy for Tremor without Interruption of Antiplatelet or Anticoagulant Therapy.","authors":"Rose M Caston, Justin M Campbell, Shervin Rahimpour, Paolo Moretti, Matthew D Alexander, John D Rolston","doi":"10.1159/000533590","DOIUrl":"10.1159/000533590","url":null,"abstract":"<p><strong>Introduction: </strong>Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is an incision-less ablative technique used to treat medically refractory tremor. Although intracerebral hemorrhage has not been reported with MRgFUS thalamotomy for the treatment of movement disorders, clinicians commonly interrupt active blood thinning medications prior to the procedure or offer gamma knife radiosurgery instead. However, MRgFUS uses focal thermoablation, and bleeding risk is likely minimal. This study aimed to evaluate the safety of MRgFUS thalamotomy in patients with essential tremor (ET) and tremor-dominant Parkinson's disease (PD) without interrupting anticoagulant or antiplatelet therapies.</p><p><strong>Methods: </strong>This was a single-center retrospective case series of all patients with ET or PD undergoing MRgFUS from February 2019 through December 2022 (n = 96). Demographic variables and medications taken at the time of surgery were obtained. Our primary outcome was the type and frequency of hemorrhagic complications noted on the operative report or postoperative imaging.</p><p><strong>Results: </strong>The mean age of patients was 74.2 years, and 26% were female. Forty patients were taking ≥1 antiplatelet or anticoagulant medications. No patient actively taking anticoagulant or antiplatelet therapies had a hemorrhagic complication during or &lt;48 h after the procedure.</p><p><strong>Conclusion: </strong>The frequency of intra- or postoperative complications from MRgFUS was not higher in patients actively taking anticoagulant or antiplatelet therapies relative to those who were not. Our findings suggest that MRgFUS thalamotomy does not necessitate interrupting anticoagulant or antiplatelet therapies. However, given the limited number of patients actively taking these therapies in our cohort (n = 40), additional testing in large, prospective studies should be conducted to further establish safety.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10591802/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10201229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artifacts Can Be Deceiving: The Actual Location of Deep Brain Stimulation Electrodes Differs from the Artifact Seen on Magnetic Resonance Images.","authors":"Noa B Nuzov,&nbsp;Bhumi Bhusal,&nbsp;Kaylee R Henry,&nbsp;Fuchang Jiang,&nbsp;Jasmine Vu,&nbsp;Joshua M Rosenow,&nbsp;Julie G Pilitsis,&nbsp;Behzad Elahi,&nbsp;Laleh Golestanirad","doi":"10.1159/000526877","DOIUrl":"https://doi.org/10.1159/000526877","url":null,"abstract":"<p><strong>Introduction: </strong>Deep brain stimulation (DBS) is a common treatment for a variety of neurological and psychiatric disorders. Recent studies have highlighted the role of neuroimaging in localizing the position of electrode contacts relative to target brain areas in order to optimize DBS programming. Among different imaging methods, postoperative magnetic resonance imaging (MRI) has been widely used for DBS electrode localization; however, the geometrical distortion induced by the lead limits its accuracy. In this work, we investigated to what degree the difference between the actual location of the lead's tip and the location of the tip estimated from the MRI artifact varies depending on the MRI sequence parameters such as acquisition plane and phase encoding direction, as well as the lead's extracranial configuration. Accordingly, an imaging technique to increase the accuracy of lead localization was devised and discussed.</p><p><strong>Methods: </strong>We designed and constructed an anthropomorphic phantom with an implanted DBS system following 18 clinically relevant configurations. The phantom was scanned at a Siemens 1.5 Tesla Aera scanner using a T1MPRAGE sequence optimized for clinical use and a T1TSE sequence optimized for research purposes. We varied slice acquisition plane and phase encoding direction and calculated the distance between the caudal tip of the DBS lead MRI artifact and the actual tip of the lead, as estimated from MRI reference markers.</p><p><strong>Results: </strong>Imaging parameters and lead configuration substantially altered the difference in the depth of the lead within its MRI artifact on the scale of several millimeters - with a difference as large as 4.99 mm. The actual tip of the DBS lead was found to be consistently more rostral than the tip estimated from the MR image artifact. The smallest difference between the tip of the DBS lead and the tip of the MRI artifact using the clinically relevant sequence (i.e., T1MPRAGE) was found with the sagittal acquisition plane and anterior-posterior phase encoding direction.</p><p><strong>Discussion/conclusion: </strong>The actual tip of an implanted DBS lead is located up to several millimeters rostral to the tip of the lead's artifact on postoperative MR images. This distance depends on the MRI sequence parameters and the DBS system's extracranial trajectory. MRI parameters may be altered to improve this localization.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9932848/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9605969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Location of the Parasympathetic Fibres within the Vagus Nerve Rootlets: A Case Report and a Review of the Literature.","authors":"Aisha Alkubaisi,&nbsp;Charles C J Dong,&nbsp;Christopher R Honey","doi":"10.1159/000528094","DOIUrl":"https://doi.org/10.1159/000528094","url":null,"abstract":"<p><p>The vagus nerve has motor, sensory, and parasympathetic components. Understanding the nerve's internal anatomy, its variations, and relationship to the glossopharyngeal nerve are crucial for neurosurgeons decompressing the lower cranial nerves. We present a case report demonstrating the location of the parasympathetic fibres within the vagus nerve rootlets. A 47-year-old woman presented with a 1-year history of medically refractory left-sided glossopharyngeal neuralgia and a more recent history of left-sided hemi-laryngopharyngeal spasm. magnetic resonance imaging showed her left posterior inferior cerebellar artery distorting the lower cranial nerves on the affected left side. The patient consented to microvascular decompression of the lower cranial nerves with possible sectioning of the glossopharyngeal and upper sensory rootlets of the vagus nerve. During surgery, electrical stimulation of the most caudal rootlet of the vagus nerve triggered profound bradycardia. None of the more rostral rootlets had a similar parasympathetic response. This case is the first demonstration, to our knowledge, of the location of the cardiac parasympathetic fibres within the human vagus nerve rootlets. This new understanding of the vagus nerve rootlets' distribution of pure sensory (most rostral), motor/sensory (more caudal), and parasympathetic (most caudal) fibres may lead to a better understanding and diagnosis of the vagal rhizopathies. Approximately 20% of patients with glossopharyngeal neuralgia also have paroxysmal cough. This could be due to the anatomical juxtaposition of the IXth cranial nerve with the rostral vagal rootlets with pure sensory fibres (which mediate a tickling sensation in the lungs). A subgroup of patients with glossopharyngeal neuralgia have neuralgia-induced syncope. The cause of this rare condition, \"vago-glossopharyngeal neuralgia,\" has been debated since it was first described by Riley in 1942. Our case supports the theory that this neuralgia-induced bradycardia is reflexively mediated through the brainstem with afferent impulses in the IXth and efferent impulses in the Xth cranial nerve. The rarer co-occurrence of glossopharyngeal neuralgia with hemi-laryngopharyngeal spasm (as seen in this case) may be explained by the proximity of the IXth nerve with the more caudal vagus rootlets which have motor (and probably sensory) supply to the throat. Finally, if there is a vagal rhizopathy related to compression of its parasympathetic fibres, one would expect it to be at the most caudal rootlet of the vagus nerve.</p>","PeriodicalId":22078,"journal":{"name":"Stereotactic and Functional Neurosurgery","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9986834/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9107833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}