Neurological Institute Pain Intensity Score Research Articles

Comparison of treatment results between microvascular decompression and gamma knife radiosurgery in primary trigeminal neuralgia.

This study aims to analyze and evaluate the comparative clinical outcomes associated with microvascular decompression (MVD) and gamma knife radiosurgery (GKRS), focusing on pain relief, pain recurrence, and complications encountered in the treatment of trigeminal neuralgia (TN). Among 155 surgical procedures performed for TN (90 GKRS, and 65 MVD) between March 1997 and December 2020, the exclusion criteria encompassed prior surgical interventions, the presence of other pathological conditions such as tumors, vascular diseases, and multiple sclerosis, as well as patients who were lost to follow-up. Ultimately, 101 patients received their initial treatment for primary TN (47 GKRS, and 54 MVD) and were followed up for more than 1 year. The MVD procedures utilized the suboccipital retrosigmoid sinus approach, whereas GKRS was conducted with MR imaging guidance, employing a single 4mm isocenter, with median GKRS doses of 80 Gy. We retrospectively analyzed patient characteristics, including sites of divisions, distributions of pain, and clinical outcomes. The assessment of outcomes was performed utilizing the Barrow Neurological Institute Pain Intensity Score and the Visual Analog Scale (VAS), with evaluations taking place preoperatively and after 1, 3, 6 and 12 months. Postoperative VAS scores for patients undergoing either MVD or GKRS demonstrated a significant improvement when compared with their preoperative counterparts. The reduction in postoperative VAS scores within the MVD group was significantly more substantial than that observed in patients who underwent GKRS at the initial postoperative evaluations (P = .037). The maintenance of pain relief after MVD proved significantly superior to that following GKRS (P < .01). Both MVD and GKRS present as safe and efficacious therapeutic options for individuals diagnosed with primary TN, though MVD displayed superior initial outcomes in terms of pain relief and its maintenance. However, for older patients or those with medical contraindications to invasive procedures, GKRS emerges as a viable and less invasive alternative for initial treatment in cases of primary TN.

Ultrasound-Guided Occipital Nerve Block in the Management of Refractory Headache and Its Outcomes: A Prospective Study

Abstract Purpose Headache severely impacts health and lifestyle, causing distress and leading to accommodative changes in affected individuals. Treatment options available for refractory headache range from a conservative approach to advanced forms. The purpose of our study was to evaluate the effectiveness of ultrasound-guided occipital nerve block (ONB) in the management of refractory headaches using visual analog scale (VAS) score and Barrow Neurological Institute Pain Intensity Score (BNIPIS). Methods A study sample of 30 eligible patients with refractory headaches including occipital neuralgia, migraine, tension headache, cluster headache, and vascular headaches aged between 18 and 65 years were included in our study. VAS and BNIPIS were noted for each patient before and after the procedure. ONB was given around the target nerve under aseptic precaution. Two milliliters of 0.5% bupivacaine was used as an injection solution for all patients. Results The mean VAS score in acute pain at pre-treatment and post-treatment after 24 hours and 3 months was found as 7.53, 1.53, and 3.20, whereas in chronic pain the score was 8.13, 3.07, and 5.87, respectively. Pre-treatment pain levels in acute and chronic subjects in BNIPIS IV and V category shifted to category I and II after 24 hours (postinjection) that later were recorded II and III, respectively, after 3 months. Conclusion Standard treatment guidelines are given by the international headache association for the management of headaches. The use of ONB is well advocated and practiced for a long time. In our study, we found that the use of greater occipital nerve block reduced pain levels affecting VAS and BNIPIS, which was more effective in acute cases than in chronic cases.

Transposition versus interposition method in microvascular decompression for trigeminal neuralgia: midterm analysis of both techniques in a single-center study.

Operative interposition of material between the trigeminal nerve and offending artery for surgical treatment of drug-resistant trigeminal neuralgia (TGN), following the Jannetta method, has been proven to be the most successful invasive treatment. Reexplorations of patients with recurrence of TGN have revealed nerve root irritations and scarring due to interposed material. To prevent these complications, modifications of microvascular decompression (MVD) aim at transposing the vessel away from the trigeminal nerve, without attachment of additional material to the nerve root. Given that both techniques (interposition and transposition) have been performed in the authors' institution, they decided to analyze them for the short- and midterm outcomes. All patients who had undergone MVD for drug-resistant TGN in the authors' institution between 2008 and 2022 were analyzed retrospectively. Outcome at discharge and follow-up was evaluated using the Barrow Neurological Institute pain intensity score. Additionally, complications and pain recurrence were assessed. A total of 114 patients were operated on using transposition and 110 patients were treated using interposition. For transposition 102 patients were followed up for a median of 31.5 months, and for interposition 100 patients were followed up for a median of 95 months. At discharge 92.1% versus 94.5% of patients in the transposition and interposition groups, respectively, experienced a good outcome (Barrow Neurological Institute pain intensity scores I-III). At follow-up, 83.3% versus 85% of patients in the transposition and interposition groups, respectively, continued to demonstrate a good outcome. In 4.9% of patients in the transposition group and in 6% of patients in the interposition group, recurrence of pain occurred. Complications occurred in 24.6% of patients in the transposition and in 27.3% of those in the interposition group. The most frequent complications were facial hypesthesia (10.5% vs 11.8%, transposition vs interposition), followed by CSF leaks (2.6% vs 8.2%). Transposition for MVD is an elegant way of solving vessel-nerve conflicts at the cerebellopontine angle. Similar to interposition, transposition shows positive short- and midterm outcomes for patients experiencing drug-resistant TGN. However, the main objective of transposition, which is improved prevention of recurrence and reduction of complications at the trigeminal nerve, could not be confirmed in this study.

The outcomes of microvascular decompression for primary trigeminal neuralgia: insights from a single-center experience and technical advancements.

Microvascular decompression (MVD) remains the primary surgical treatment for trigeminal neuralgia due to its positive postoperative results. This study aims to evaluate the outcomes of patients with primary trigeminal neuralgia who underwent MVD. Additionally, the paper offers a detailed explanation of the surgical methodology of MVD employed at the neurosurgical hospital in Kazakhstan. The study involved 165 medical records of patients with trigeminal neuralgia who underwent MVD between 2018 and 2020. Out of these 165 patients, 90 (54.55%) were included in the final analysis and were further evaluated using the Barrow Neurological Institute pain intensity score. Various variables were analyzed, including age, sex, affected side, dermatomes, offending vessel, and surgical intervention type. Moreover, the surgical technique employed at the hospital was described. The average follow-up period after the MVD procedure was 32.78 ± 9.91 months. The results indicated that out of the 90 patients, 80 (88.89%) achieved a good outcome as evidenced by BNI scores I and II. It was observed that patients with affected maxillary dermatomas and those with affected ophthalmic + maxillary dermatomas were more likely to experience fair + poor postsurgery BNI scores. On the other hand, patients with neurovascular conflicts involving the maxillary + mandibular dermatomas demonstrated good BNI scores (p = 0.01). The outcomes of MVD in patients with primary trigeminal neuralgia showed good BNI scores within this study population. The outcome depended on the affected dermatome of the trigeminal nerve with the vessel. Additionally, patient positioning, intraoperative management including small skin incisions, minimal craniotomy, and precise closure of the dura, as well as intraoperative neurolysis, may contribute to achieving good clinical and satisfactory post-surgery aesthetic outcomes.

Microvascular decompression for trigeminal neuralgia: an experience of 84 operated cases

AimWe retrospectively analyse and review the results of microvascular decompression performed for trigeminal neuralgia. We also discuss the surgical nuances, complication avoidance and compare our results with other reported studies.Materials and methodsThis is a retrospective study in which the data of eighty-four patients who underwent microvascular decompression for trigeminal neuralgia in the last ten years from 2013 till May 2023 at our institute (Neuron hospital and SSG Hospital, Vadodara, India) was reviewed. The preoperative pain characteristics, radiology reports and the degree and duration of post-operative pain relief and neurologic outcome was assessed. MRI was done preoperatively in all the cases to rule out a secondary cause for trigeminal neuralgia. All the cases of secondary trigeminal neuralgia were excluded from the study. A favourable outcome was defined as a post-operative Barrow Neurological Institute pain intensity score of 1.ResultsEighty patients had excellent immediate postoperative pain relief without any need for medications. None of these patients have developed any recurrence of pain till date. Four operated patients did not experience any pain relief after surgery.ConclusionMicrovascular decompression for trigeminal neuralgia is a safe and effective procedure which treats the root cause of the disease and hence provides good long term pain relief.

Microsurgical posterior fossa re-exploration for recurrent trigeminal neuralgia after previous microvascular decompression: common grounds—scarring, deformation, and the “piston effect”

ObjectiveMicrovascular decompression (MVD) is a well-accepted treatment modality for trigeminal neuralgia (TN) with high initial success rates. The causes for recurrence of TN after previously successful MVD have not been fully clarified, and its treatment is still a matter of debate. Here, we present the surgical findings and the clinical outcome of patients with recurrent TN after MVD who underwent posterior fossa re-exploration.MethodsMicrosurgical posterior fossa re-exploration was performed in 26 patients with recurrent TN (mean age 59.1 years) who underwent MVD over a period of 10 years. The trigeminal nerve was exposed, and possible factors for recurrent TN were identified. Arachnoid scars and Teflon granulomas were dissected meticulously without manipulating the trigeminal nerve. Outcome of posterior fossa re-exploration was graded according to the Barrow Neurological Institute (BNI) pain intensity score. Follow-up was analyzed postoperatively at 3, 12, and 24 months and at the latest available time point for long-term outcome.ResultsThe mean duration of recurrent TN after the first MVD was 20 months. Pain relief was achieved in all patients with recurrent TN on the first postoperative day. Intraoperative findings were as follows: arachnoid scar tissue in 22/26 (84.6%) patients, arterial compression in 1/26 (3.8%), venous contact in 8/26 (30.8%), Teflon granuloma in 14/26 (53.8%), compression by an electrode in Meckel’s cave used for treatment of neuropathic pain in 1/26 (3.8%), evidence of pulsations transmitted to the trigeminal nerve through the Teflon inserted previously/scar tissue (“piston effect”) in 15/26 (57.7%), and combination of findings in 18/26 (69.2%). At long-term follow-up (mean 79.5 months; range, 29–184 months), 21/26 (80.8%) patients had favorable outcome (BNI I-IIIa). New hypaesthesia secondary to microsurgical posterior fossa re-exploration occurred in 5/26 (19.2%) patients.ConclusionsPosterior fossa re-exploration avoiding manipulation to the trigeminal nerve, such as pinching or combing, may be a useful treatment option for recurrent TN after previously successful MVD providing pain relief in the majority of patients with a low rate of new hypaesthesia.

Frameless Linear Accelerator (LINAC) Based Radiosurgery (SRS) vs. Framed Gamma Knife SRS for Idiopathic Trigeminal Neuralgia (TN)

Stereotactic radiosurgery (SRS) is an effective treatment for idiopathic trigeminal neuralgia (TN). Conventional treatment is done through frame-based solution due to small target and high radiation dose. More recently, LINAC based frameless SRS technique has been established as a patient friendly alternative. Herein we compared our single institution experience of LINAC based frameless SRS vs frame-based gamma knife SRS for TN. The hypothesis is LINAC based frameless SRS can provide equivalent dosimetric and clinical outcome as compared frame-based gamma knife treatment. Patients with idiopathic TN who received SRS treatment (LINAC based frameless treatment or Gamma knife framed treatment) at our institution from 2015-2022 were included. A minimum follow up of 1 year was required. Patient data was extracted from electronic medical records and radiation treatment planning system. Pain intensity was evaluated utilizing a modified 0-4 Barrow Neurological Institute (BNI) pain intensity score, and then dichotomized where BNI score 0-2 represented response to treatment and BNI score 3-4 represented no response. Statistical analysis was conducted with a linear regression model accounting for race, gender, prior pain, pain distribution including laterality and branch involvement, medication regimen at time of treatment, previous radiation treatment, and prior procedures. Response was then compared between both modalities overall and within each sub-group with chi-square testing and linear regression. A total of 81 patients were identified, 14 patients were excluded due to lack of adequate follow-up, leaving 67 for analysis. 12 (17.9%) were male and, 55 (82.1%) were female. All patients were managed with medication prior to SRS treatment. 5 (7.5%) had rhizotomy and 13 (19.4) had microvascular decompression, and 8 (11.9%) had previous gamma-knife radiosurgery prior to SRS treatment at our institution. Of the 67 patients, 23 (34.3%) received frame-based gamma knife SRS, 44(65.7%) received frameless LINAC treatment. 58 (86.6%) radiation naïve patients received 90 Gy in 1 fraction, while out of the 9 who had previously had intracranial radiation treatment 7 (10.4%) received 70 Gy and 2 (3%) received 80 Gy all prescribed to 100% isodose line. All patients were treated with 4 mm cone. There was no significant difference in brainstem dose between these two techniques. Between LINAC-based or Gamma Knife modalities rate of pain control (77.3 % vs 82.6 %, respectively, p = 0.61) as well as toxicity in facial numbness (31.8% vs 21.7%, respectively, p = 0.38) showed no statistical difference. There was no statistically significant signal (p > 0.05) detected within the subgroups analyzed. The linear regression model also showed no significant difference. LINAC based frameless SRS provides comparable dosimetry and pain control for TN as compared to frame-based gamma knife treatment. It is a patient friendly solution for patients with TN.

A Comparative Review of the Outcome Following MVD and PBC in Patients with Trigeminal Neuralgia.

This study aims to systematically review the treatment outcomes of percutaneous balloon compression (PBC) and microvascular decompression (MVD) in patients with trigeminal neuralgia. A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline was performed using PubMed, Embase, and Cochrane Central Registry of Controlled Trials databases. Only those articles with more than 5 years' follow-up length were included in this investigation. To uniformly assess the postoperative outcome, we defined pain relief as totally pain free, while the postoperative hospitalization and last follow-up period were defined as early and long term, respectively. The facial numbness was quantified with Barrow Neurological Institute Pain Intensity Score (BNI). After database searching and screening, 7,797 cases were finally included according to the criteria. The early pain relief rates were 94.1% (1,551/1,649) and 89.9% (4,962/5,482) following PBC and MVD (odds ratio [OR] = 0.603; p < 0.05), while the long-term rates were 58.1% (921/1,566) and 74.9% (4,549/6,074; OR = 2.089; p < 0.05), respectively. Although a significant higher facial numbness occurred in the PBC group in the early stage, it was mostly diminished 5 years later compared with the MVD group. At long-term follow-up, hypoacusis and facial palsy occurred more often in the MVD group (p < 0.05). Both MVD and PBC provide a satisfactory outcome for the patients in the long term. As a simple, safe, and reliable technique, PBC should be considered as a viable alternative.

Robot-assisted percutaneous balloon compression for trigeminal neuralgia- preliminary experiences

ObjectivesThis study aims to discuss the availability of robot-assisted percutaneous balloon compression (PBC) for trigeminal neuralgia (TN) and share our preliminary experiences.MethodsPatients with TN who underwent robot-assisted PBC from June to September 2022 were enrolled. We designed a fixing plug for robot-assisted PBC, three-dimensional structured light registration was used, puncture trajectory was the line connects the medial third of inner and outer aperture of foramen ovale. Numerical Rating Scale (NRS), Barrow Neurological Institute (BNI) pain and numbness intensity score were used to evaluate the facial pain and numbness.ResultsEventually, nine patients were enrolled, the structured light registrations were successfully finished in all patients with a mean registration error of 0.68 mm. All the punctures of foramen ovales were successfully done one-time. Of note, the balloons were all got pear-shaped followed by 150 to 180 s compression. Though, postoperatively, all the patients complained of facial numbness and four patients suffered from transient masseter weakness, all patients got fully or mostly pain relief. It should be noted that is the numbness and weakness gradually relieved during follow-up.ConclusionThree-dimensional structured light registration and robot assisted PBC is an effective choice for patients with TN. Extension line between the medial third of the inner and outer aperture of foramen ovale might be a safe and effective puncture trajectory to this procedure.

838 Gamma Knife Stereotactic Radiosurgery Retreatment of Trigeminal Neuralgia: Prognostic Factors and Clinical Outcomes

INTRODUCTION: Trigeminal neuralgia(TN) is a debilitating nerve disorder affecting approximately 4.5 per 100,000 people annually. While medical management is the first line of treatment, Gamma Knife Stereotactic Radiosurgery(GKSRS) may be used. Long-term outcomes after GKSRS retreatment are not well elucidated. METHODS: Of the 168 patients treated since 2012 at our institution, 149 had adequate follow-up data, and 53(40.4%) received 2 treatments. The Barrow Neurological Institute (BNI) pain intensity score was used to grade pain. Pain relief was defined as post-GKSRS BNI score of I-III. Treatment failure was defined as post-GKSRS score of IV-V without pain-relief. Pain-recurrence was defined as a post-GKSRS score of IV-V after achieving pain-relief. Univariable analyses were performed to examine the effects of multiple factors on outcomes. RESULTS: Median follow-up was 15(1-63) months; 136(90%) and 49(83.0%) patients achieved pain-relief after T1 and T2 respectively. Median time to pain-relief was 3 months and 1 month after T1 and T2 respectively. Median freedom from pain-recurrence was 24.0 months and 13.7 months following T1 and T2 respectively; 44 (30.0%) and 6 (12.2%) patients developed pain-recurrence following T1 and T2 respectively. High KPS score, V1+V2 pain distribution, and absence of mastication deficits reduced the risk of T1 treatment failure by 21%, 58%, and 54% respectively(p&lt;0.05). Patients with lower BNI scores after T1 had a 39% reduced risk of T2 failure(p&lt;0.001); 2(1.3%) and 4(6.8%) patients developed facial and/or mastication deficits following T1 and T2 respectively. Neither isocenter location nor dose affected outcomes. CONCLUSIONS: GKSRS remains an effective treatment for patients with refractory TN. Our data show that patients who fail or recur after T1 may still receive symptomatic relief following T2 with minimal toxicity. Abstract not yet presented, but accepted for presentation at ASTRO 2022

Classical trigeminal neuralgia recurrence after vascular decom - pression: analysis of the causes and features of the clinical picture

Introduction. Pain syndrome recurrence in patients with classical trigeminal neuralgia (CTN) after surgical treatment is an important and relevant issue, despite the advances in the diagnosis of the disease, progress in approaches to patient selection, and proven surgical tactics. The aim of the study is to evaluate the affecting factors for redo surgery in patients with CTN recurrence. Materials and methods. 257 patients with CTN recurrence operated on at the FSAI N.N. Burdenko National Medical Research Center for Neurosurgery of the Ministry of Health of the Russian Federation for the period from 2012 to 2017 were involved in the prospective nonrandomized study. Intraoperative findings and pain structure in postoperative period were evaluated in patients after revision surgery. Burchiel classification, DN4 Questionnarie, and Barrow Neurological Institute Pain Intensity Score (BNI-PS) were used. Results. CTN recurrence in the early and late post-operative periods was registered in 33 patients, which accounted for 13% of the total number of patients in the study group. 58% of them underwent secondary surgical intervention. The efficacy of redo surgery was noted in 79% of patients with complete regression of pain. Patients with CTN and neuropathy combination were admitted to alternative methods (neuromodulation, radiosurgery, radiofrequency ablation). In patients who received stimulation of the branches of the trigeminal nerve after vascular decompression, pain regression was observed in 100% of cases. Patient distribution after combined treatment was 78% for BNI-PS score I and 22% for BNI-PS score 2-3, respectively. Conclusion. In patients with “pure” CTN recurrence, redo surgery presents an effective method of treatment. In patients with CTN and neuropathy combination, repeat vascular decompression is effective only in terms of paroxysmal pain. Thus, multidisciplinary approach is needed – combining adjunctive methods of treatment in neurology, neurosurgery, pain management, and radiotherapy.

Gamma Knife Central Lateral Thalamotomy for Chronic Neuropathic Pain: A Single-Center, Retrospective Study.

Chronic neuropathic pain can be severely disabling and is difficult to treat. The medial thalamus is believed to be involved in the processing of the affective-motivational dimension of pain, and lesioning of the medial thalamus has been used as a potential treatment for neuropathic pain. Within the medial thalamus, the central lateral nucleus has been considered as a target for stereotactic lesioning. To study the safety and efficacy of central lateral thalamotomy using Gamma Knife radiosurgery (GKRS) for the treatment of neuropathic pain. We retrospectively reviewed all patients with neuropathic pain who underwent central lateral thalamotomy using GKRS. We report on patient outcomes, including changes in pain scores using the Numeric Pain Rating Scale and Barrow Neurological Institute pain intensity score, and adverse events. Twenty-one patients underwent central lateral thalamotomy using GKRS between 2014 and 2021. Meaningful pain reduction occurred in 12 patients (57%) after a median period of 3 months and persisted in 7 patients (33%) at the last follow-up (the median follow-up was 28 months). Rates of pain reduction at 1, 2, 3, and 5 years were 48%, 48%, 19%, and 19%, respectively. Meaningful pain reduction occurred more frequently in patients with trigeminal deafferentation pain compared with all other patients (P = .009). No patient had treatment-related adverse events. Central lateral thalamotomy using GKRS is remarkably safe. Pain reduction after this procedure occurs in a subset of patients and is more frequent in those with trigeminal deafferentation pain; however, pain recurs frequently over time.

A Non-Invasive Stereotactic Radiosurgery Instrument Stereotactic Radiosurgery Retreatment of Trigeminal Neuralgia: Prognostic Factors and Clinical Outcomes

<h3>Purpose/Objective(s)</h3> Trigeminal neuralgia (TN) is a debilitating nerve disorder that affects approximately 4.5 per 100,000 people each year. While medical management is the first line of treatment for medically refractory patients, surgical intervention or a non-invasive stereotactic radiosurgery instrument may be used. The long-term outcomes of patients who have received GK SRS retreatment for refractory TN are not well elucidated. The objective of this study is to report the outcomes of patients with refractory TN following their first GK SRS treatment (T1). <h3>Materials/Methods</h3> 381 patients have received ≥ T1 for TN from 2012-present at our institution. The outcomes of 59 patients with refractory TN who received ≥ 2 GK SRS treatments (T2) were analyzed. 53 cases (89.8%) received T2, 5 cases (8.5%) received 3 treatments, and 1 case (1.7%) received 4 treatments. For T1, 57 cases (96.6%) were treated to a dose of 40 Gy to the 50% isodose volume (IDV). For T2, 40 cases (71.4%) were treated to a dose of 35 Gy to the 50% IDV, and 16 cases (28.6%) were treated to a dose of 40 Gy to the 50% IDV. The Barrow Neurological Institute (BNI) pain intensity score was used to grade pain. Pain relief was defined as a post-GK SRS BNI score of I-III. Pain recurrence was defined as a post-GK SRS score of IV-V after initially achieving pain relief. Treatment failure was defined as a post-GK SRS score of IV-V without having achieved pain relief. Univariate analyses were performed to examine the effects of treatment planning, patient demographics, and TN symptom characteristics on outcomes. <h3>Results</h3> The median follow-up was 46 months after T1 (9-144 months). 52 cases (88.1%) had a BNI score of IV-V prior to T2. Overall, 52 cases (88.1%) and 49 cases (83.0%) achieved pain relief after T1 and T2, respectively. The median time to pain relief was 0.7 and 1.0 months after T1 and T2, respectively. The median freedom from pain recurrence was 7.7 and 13.7 months following T1 and T2, respectively. Only 6 cases (12.2%) developed pain recurrence following T2. High KPS scores, combined V1 + V2 pain distribution, and painless mastication prior to T1 were factors that reduced the risk of T1 treatment failure (21%, 58%, and 54%, respectively; p<0.05). Patients with lower BNI scores after T1 with subsequent pain recurrence had a 39% reduced risk of T2 failure (p<0.001). Neither isocenter location nor dose affected outcomes in this study. No T1 or T2 patients were entirely pain free without supplemental medical therapy. Only 1 patient (1.7%) developed CN VII weakness following T2. No patients developed CN V or CN VII weakness following T3 or T4. <h3>Conclusion</h3> GK SRS remains an effective treatment choice for patients with refractory TN. In fact, patients who fail or recur after T1 experience a longer pain-free interval following T2 with minimal toxicity. Low KPS score, painful mastication, and pain distributions other than V1 + V2 were all associated with increased risk of T1 failure. Patients who achieved lower BNI scores after T1 with pain recurrence were more likely to achieve pain relief after T2.

Macrovascular Decompression with the Transposition Method Using Teflon Sling for Trigeminal Neuralgia Caused by the Vertebrobasilar Artery

Complete separation of the vertebrobasilar artery (VBA) from the trigeminal nerve by microvascular decompression is technically challenging. This paper evaluates the transposition method using Teflon sling for trigeminal neuralgia (TN) caused by the VBA. Retrospective review of 32 patients including 2 patients with tic convulsif. Mobilization of the VBA in the anteromedial-caudal direction and repositioning of the VBA using Teflon sling and fibrin glue were performed. Pre- and postoperative pain were evaluated with the Barrow Neurological Institute (BNI) pain intensity score. Duration of surgery and postoperative neurologic complications were reviewed. Preoperative BNI score ranged from III to V. Postoperative BNI score I was observed in 30 patients, II in 1 patient, and V in 1 patient as recurrence. Abducens nerve palsy was observed in 9 patients but was transient in 8. Permanent hearing loss was observed in 6 patients. Transient mild lower cranial nerve palsy was recorded in 2 patients with tic convulsif. Average surgical time was 290 minutes. Our method for trigeminal neuralgia caused by VBA was very effective, but the complication rate of cranial nerve disorders was also high. A high rate of complications implied the technical difficulty of extensive vascular mobilization requiring long duration of surgery. Macrovascular decompression surgery is more descriptive of this surgery instead of microvascular decompression surgery.

Technical Assessment of Microvascular Decompression for Trigeminal Neuralgia Using a 3-Dimensional Exoscope: A Case Series.

Detailed anatomic visualization of the root entry zone of the trigeminal nerve is crucial to successfully perform microvascular decompression surgery (MVD) in patients with trigeminal neuralgia. To determine advantages and disadvantages using a 3-dimensional (3D) exoscope for MVD surgery. A 4K 3D exoscope (ORBEYE) was used by a single surgical team for MVD in a retrospective case series of 8 patients with trigeminal neuralgia in a tertiary center. Clinical and surgical data were collected, and advantages/disadvantages of using the exoscope for MVD were recorded after each surgery. Descriptive statistics were used to summarize the data. Adequate MVD of the trigeminal nerve root was possible in all patients by exclusively using the exoscope. It offered bright visualization of the cerebellopontine angle and the root entry zone of the trigeminal nerve that was comparable with a binocular operating microscope. The greatest advantages of the exoscope included good optical quality, the pronounced depth of field of the image for all observers, and its superior surgeon ergonomics. Disadvantages were revealed with overexposure at deep surgical sites and the lack of endoscope integration. In 6 patients, facial pain improved significantly after surgery (Barrow Neurological Institute pain intensity score I in 5 and III in 1 patient), whereas it did not in 2 patients (Barrow Neurological Institute score IV and V). No complications occurred. Utilization of a 3D exoscope for MVD is a safe and feasible procedure. Surgeons benefit from better ergonomics, excellent image quality, and an improved experience for observers.

Fully Endoscopic Microvascular Decompression for Trigeminal Neuralgia: Technical Note Describing a Single-Center Experience

Microscopic microvascular decompression (MVD) of the trigeminal nerve is the gold standard surgical treatment for medically refractory classical trigeminal neuralgia. Endoscopy has significantly advanced surgery and provides enhanced visualization of the cerebellopontine angle and its critical neurovascular structures.We present our initial experience of fully endoscopic microvascular decompression (e-MVD). This retrospective case series investigated e-MVD performed from September 2016 to February 2020 at a single institution. Clinical data including presenting symptoms, medications, operative findings, postoperative complications, and outcomes were recorded. The 5-point Barrow Neurological Institute (BNI) pain intensity score was used to quantify patients' pain relief. During the study period, 25 patients with trigeminal neuralgia (10 males, 15 females; mean [SD] age= 63 [10.4] years) underwent e-MVD. All patients had a preoperative BNI score of V. The left side was affected in 15 patients. Complications occurred in 2 patients: both experienced hearing loss, and one experienced transient facial weakness 7 days after surgery. The facial weakness had resolved by the last follow-up. All patients were completely pain-free (BNI score I) immediately postoperatively. On latest follow-up, 22 patients have remained pain-free, and 3 patients have recurrent pain that is being controlled with medication (BNI score III). Our study demonstrated that e-MVD is a safe, possibly effective method of performing MVD with the added benefit of improved visualization of the operative field for the operating surgeon and the surgical team. Larger prospective studies are required to evaluate whether performing e-MVD confers any additional benefits in long-term clinical outcome of patients with trigeminal neuralgia.

189 Arterial Hypertension Independently Predicts Recurrence After Microvascular Decompression for Trigeminal Neuralgia—A Modifiable Risk Factor as a Key Component

INTRODUCTION: Microvascular decompression is highly effective for the management of classical refractory trigeminal neuralgia. Nonetheless, predictors of post-operative prognosis are incompletely understood. METHODS: We performed a retrospective analysis of the classical trigeminal neuralgia cases submitted to microvascular decompression in our center between 2003 and 2019. 57 patients were identified and pre-op clinical and imagiological characteristics, surgical findings, complications and pain control – both immediate and long-term – were described. Outcome was measured using the Barrow Neurological Institute Pain Intensity Score (BNIPIS). RESULTS: Mean age at procedure was 63.9 years, with a female predominance (66.7%). Most symptoms were in the V2 and V3 territory and the most common trigger identified was mastication. History of arterial hypertension was identified in 49.1%. Vascular contact at surgery was identified in almost all patients (97.6%). Regarding pain outcome results, at 6 months post-op, 80.7% of patients had a good recovery (BNIPIS = 3). This result was maintained at 12 months, with 78.9% of patients having a good outcome. At long follow-up (median 77 months), 82.5% of patients had a BNIPIS = 3, with 50% achieving a BNIPIS 1. Recurrence was identified in 37.3% of patients, with a median of 44 months. On multivariate analysis, hypertension was independently associated with recurrence (OR = 4.9; 95% CI 1.2-19.3; p = 0.023). CONCLUSION: Microvascular decompression is a valuable resource for managing refractory trigeminal neuralgia. Factors associated with recurrence are poorly understood. Arterial hypertension, a potentially modifiable risk factor, might be a recurrence predictor, possibly by modulating local vascular phenomena. Better understanding of the pathophysiology involved can provide physicians means to overcome this incapacitating disease.

Decompression of the Greater Occipital Nerve for Occipital Neuralgia and Chronic Occipital Headache Caused by Entrapment of the Greater Occipital Nerve.

Chronic entrapment of the greater occipital nerve (GON) can not only manifest in typical stabbing pain of occipital neuralgia (ON) but also lead to continuous ache and pressure-like pain in the occipital and temporal areas. However, the effect of GON decompression on these symptoms has yet to be established. We report the follow-up results of GON decompression in typical cases of ON and chronic occipital headache due to GON entrapment (COHGONE). A 1-year follow-up study of GON decompression was conducted on 11 patients with typical ON and 39 COHGONE patients with GON entrapment. The degree of pain reduction was analyzed using the numerical rating scale-11 (NRS-11) score and percent pain relief before and 1 year after surgery. A success was defined by at least a 50% reduction in pain measured via NRS-11 during the 12-month follow-up. To assess the degree of subjective satisfaction, a 10-point Likert scale was used. Postoperative outcome was also evaluated using the Barrow Neurological Institute (BNI) pain intensity score. The difference in GON decompression between the patients with typical ON and those with COHGONE was studied. GON decompression was successful in 43 of 50 patients (86.0%) and percent pain relief was 72.99 ± 25.53. Subjective improvement based on a 10-point Likert scale was 7.9 ± 2.42 and the BNI grade was 2.06 ± 1.04. It was effective in both the ON and COHGONE groups, but the success rate was higher in the ON group (90.9%) than in the COHGONE group (84.6%), showing statistically significant differences in the results based on average NRS-11 score, percent pain relief, subjective improvement, and BNI grades (p < 0.05, independent t-test). GON decompression is effective in chronic occipital headache and in ON symptoms induced by GON entrapment.

”PTFE Sleeve Graft” Technique to Remove Neurovascular Conflict in Micro Vascular Decompression for Trigeminal Neuralgia

Microvascular decompression (MVD) of the trigeminal nerve is a well-accepted nondestructive procedure for trigeminal neuralgia. Usually, Teflon (PTFE) puff or felt graft techniques, which are most commonly used, are associated with arachnoiditis and recurrence among other complications. We use the "sleeve graft" technique using PTFE to separate the neurovascular conflict and here we describe our experience with the same in 376 cases. To study the outcomes in 376 patients treated with sleeve graft technique for trigeminal neuralgia. For a period of 18 years, from 2002 to 2020, all cases of medically refractory trigeminal neuralgia were subjected to the "sleeve graft" technique for MVD. Pre- and post-operatively, pain score was given according to Barrow Neurological Institute pain intensity score. Cases were observed for any complications and pain relief in short and long-term follow-up. In total, 376 cases of refractory primary trigeminal neuralgia cases, among which 198 patients underwent MVD with no prior intervention, 158 underwent MVD following percutaneous ablative procedure, 13 were "Revision MVD" previously done at other centers, and four were post gamma knife failure. There was no incidence of arachnoiditis or recurrence of symptoms. Further, 368 (97.8%) patients had complete recovery from symptoms while eight (2.2%) had partial recovery after 5 years of follow-up. Complications included hearing loss (n = 1), temporary hypoesthesia (n = 45), and permanent hypoesthesia (n = 7). "PTFE Sleeve Graft" technique to remove the neurovascular conflict in micro vascular decompression (MVD) for trigeminal neuralgia is a safe and effective technique that yields better results.

Long-term Efficacy of Gamma Knife Radiosurgery on Pain Control in Trigeminal Neuralgia.

Gamma Knife is an essential treatment alternative for treatment-resistant trigeminal neuralgia (TN). This study investigated the efficacy of Gamma Knife radiosurgery (GKRS) in patients with Burchiel type 1 and 2 TN. A retrospective analysis of prospectively collected data of 163 patients who underwent GKRS between December 2006 and December 2021 was performed. The median follow-up was 37 (range, 6-168) months. The target was the cisternal portion of the trigeminal nerve, and the median prescribed dose was 85 (range, 75-90) Gy. Pain severity was evaluated using the Barrow Neurological Institute (BNI) pain intensity score. All patients had BNI IV or V before GKRS. BNI IIIb or better was defined as adequate pain relief. Logistic regression analysis was conducted to determine the prognostic significance of different pretreatment and treatment variables. The initial pain relief rate was 85%, with a median period of 25 (range, 1-90) days. At the final follow-up, 62.5% of patients had adequate pain relief. BNI I was achieved in 8% of patients within the first 24 h after GKRS; this rate was 22% at the final follow-up. The predicted adequate pain relief rates at the 3rd and 6th month and 1st, 3rd, 5th, and 7th year were 84%, 79%, 76%, 67%, 59%, and 55%, respectively. The complication rate was 8%, with disturbing facial sensorial dysfunction in four patients, decreased corneal reflex in three patients, and masseter dysfunction in six patients. Univariate and multivariate logistic regression analyses revealed Burchiel type 1 TN (p = 0.001) and male gender (p = 0.037) as predictors of increased initial pain relief rate and shorter time to initial pain relief day, respectively. Appropriate patient selection is the key to successful TN treatment. GKRS can be recommended, especially for patients with Burchiel type 1 TN, with low complication rates and effective long-term pain relief.