This study aimed to investigate the clinical efficacy and early outcomes of endoscopic microvascular decompression (MVD) for primary trigeminal neuralgia (TN) and provide clinical experience for the application of full endoscopic techniques in MVD surgery.

This study retrospectively collected medical records of patients who underwent microvascular decompression (MVD) surgery at our institution between January 2020 and January 2023. According to predefined inclusion and exclusion criteria, a total of 137 patients were ultimately included in the study. To evaluate the severity of facial pain in these patients, we utilized the Barrow Neurological Institute (BNI) pain intensity rating system. Additionally, this study analyzed and compared the clinical outcomes of MVD procedures performed endoscopically versus those performed under microscopy.

There were no statistically significant differences between endoscopic and microscopic microvascular decompression (MVD) in terms of postoperative hospital stay, recurrence rate, complication incidence, and surgical duration (P > 0.05). However, regarding the efficacy of treatment, the effectiveness rate after endoscopic MVD was superior to that of microscopic MVD, with a statistically significant difference observed between the two groups (P < 0.05).

Endoscopic microvascular decompression (MVD) for primary trigeminal neuralgia is a safe and effective treatment, with the critical success factor being the accurate localization of the vessel compressing the nerve. Compared to traditional microscopic MVD, endoscopic MVD shows superior postoperative outcomes, offering wide-angle and multi-angle views along with close-up inspection capabilities. However, it requires attention to overcoming limitations such as a lack of stereoscopic vision and potential blind spots.

Microvascular decompression (MVD), radiofrequency rhizotomy (RFR), and stereotactic radiosurgery (SRS) are surgical techniques frequently used in the treatment of idiopathic trigeminal neuralgia (TN), although the results reported for each of these are diverse.

This study aimed to compare long-term pain control obtained by MVD, SRS, and RFR in patients with idiopathic TN.

To compare the results obtained by MVD, SRS, and RFR we chose a quasi-experimental, ambispective design with control groups but no pretest. A total of 52 participants (MVD n = 33, RFR n = 10, SRS n = 9) were included. Using standardized outcome measures, pain intensity, pain relief, quality of life, and satisfaction with treatment were assessed by an independent investigator. The TREND statement for reporting non-randomized evaluations was applied. Clinical outcomes were evaluated at the initial postoperative period and at 6 months, 1, 2, 3, 4, and 5 years postoperatively.

MVD has shown better results in pain scales compared to ablative procedures. Significant differences between groups were found regarding pain intensity and pain relief at the initial postoperative period (p < 0.001) and 6 months (p = 0.022), 1 year (p < 0.001), 2 years (p = 0.002), and 3 years (p = 0.004) after the intervention. Those differences exceeded the thresholds of the minimal clinically important difference. A higher percentage of patients free of pain was observed in the group of patients treated by MVD, with significant differences at the initial postoperative period (p < 0.001) and 6 months (p = 0.02), 1 year (p = 0.001), and 2 years (p = 0.04) after the procedure. Also, a higher risk of pain recurrence was observed in the RFR and SRS groups (HR 3.15, 95% CI 1.33-7.46; p = 0.009; and HR 4.26, 95% CI 1.77-10.2; p = 0.001, respectively) compared to the MVD group. No significant differences were found in terms of quality of life and satisfaction with treatment. A higher incidence of complications was observed in the MVD group.

Concerning pain control and risk of pain recurrence, MVD is superior to RFR and SRS, but not in terms of quality of life, satisfaction with treatment, and safety profile.

Trigeminal neuralgia (TN) is a highly disabling facial pain syndrome, historically known as the suicide disease, in which most cases can be cured with appropriate surgical treatment.

We present the case of a 43-year-old male farmer with acute, self-limiting episodes of shock-like pain on the left side of the face that started in June of 2021. He was diagnosed with TN and was treated with carbamazepine. Magnetic resonance imaging was performed, which revealed an epidermoid cyst (EC) at the prepontine cistern with an extension to the left cerebellopontine angle. The neurosurgery department at our institution was consulted, which performed surgical tumor resection and Vth cranial nerve decompression. During the resection, a neurovascular conflict (NVC) was identified at the root entry zone. After the resection around the nerve and its whole tract was completed, a microvascular decompression (MVD) was performed.

TN secondary to EC in association with a NVC is a rare phenomenon, due to the growth pattern of the EC. TN may remit if an appropriate treatment is carried out. In cases of NVC, an MVD is required apart from an appropriate resection to achieve pain relief.

Percutaneous glycerol rhizotomy successfully treats trigeminal neuralgia although failure rates and durability of the procedure are variable. Some of this variability in clinical outcome might be due to egress of glycerol from Meckel's cave (MC) because of surgical positioning and individual patient anatomy. In this article, we quantitatively analyzed the anatomic variances that affect glycerol fluid dynamics to better predict patients more amenable for percutaneous glycerol injections.

Computed tomography imaging of 11 cadaveric heads was used to calculate bilateral Clival-Meckel's cave (CMC) and sella-temporal (ST) angles. Twenty-two cadaveric percutaneous injections of dyed glycerol into the Meckel's cave were performed using Härtel's approach, and the fluid movement was documented at prespecified intervals over 1 hour. The relationship between the angles and glycerol migration was studied.

Specimens with basal cistern involvement by 60 minutes had significantly greater CMC angles (median [IQR]: basal cistern involvement = 74.5° [59.5°-89.5°] vs no basal cistern involvement = 58.0° [49.0°-67.0°]), U = 6.0, P < .001. This model may predict which patients will experience glycerol migration away from the Gasserian ganglion (area under the curve: 0.950, SE: 0.046, CI: 0.859-1.041, P < .001). Increased ST angle was associated with lateral flow of glycerol (r s = 0.639, P = .001), and CMC angle was associated with total area of dispersion (r s = -0.474, P = .026).

Anatomic variation in skull base angles affects glycerol migration. Specifically, a more obtuse CMC angle was associated with a higher risk of posterior migration away from the Gasserian ganglion. This may be a reason for differing rates of surgical success. These results suggest that anterior head flexion for 60 minutes may prevent percutaneous glycerol rhizotomy failures and some patients with large CMC angles are more likely to benefit from postinjection head positioning. However, this clinical effect needs validation in vivo.

Percutaneous glycerol rhizotomy (PGR) is a minimally invasive procedure for patients with trigeminal neuralgia who are not candidates for microvascular decompression. PGR has widely varying success rates. It has been postulated that differences in post-injection head positioning might account for the various success rates.

By comparing glycerol dispersion after injection at various head positions, we provide the first evidence supporting post-injection head flexion positioning. Furthermore, we study the clival-Meckel cave (CMC) angle as a predictor of beneficial glycerol flow, measured on computed tomography images. Twenty-two dissected cadaveric specimens were injected with dyed glycerol through the Hartel approach. The glycerol dispersion was measured at prespecified intervals for 1 hour. The Mann-Whitney U and χ2 tests were used to determine the most ideal angle of head flexion to avoid posterior glycerol dispersion and ensure V1-V3 branch glycerol submersion.

We found that 30° of anterior head flexion provided optimal trigeminal nerve glycerol submersion (81.82%) in comparison to neutral (27.27%) and 15° (68.18%), P < 0.001. There was minimal unfavorable dispersion beyond 30 minutes at all angles. More obtuse CMC angles were associated with higher rates of unfavorable BC dispersion (U = 6.0; P = 0.001). For specimens with CMC angles >75°, unfavorable BC dispersion was prevented by head flexion (U = 4.5; P = 0.021). We show that 30° of lateral head tilt achieves V1 submersion in all specimens by 30 minutes [X2(1,N = 44) = 22.759; P < 0.001].

We found that 30° anterior head flexion for >30 minutes provides ideal conditions for PGR to avoid BC dispersion and ensure V1-V3 branches achieve glycerol submersion. For patients with V1 symptoms, contralateral head flexion might help optimize treatment effects.

To investigate the clinical efficacy of percutaneous microballoon compression in the treatment of recurrent TN.

This retrospective study included 33 patients who underwent percutaneous microballoon compression for the treatment of recurrent TN from March 2019 to May 2022. Postoperative pain recurrence and facial numbness were assessed according to the Barrow Neurological Institute (BNI) pain score. Patients' anxiety and sleep status during follow-up were assessed according to the Self-rating Anxiety Scale (SAS) and Pittsburgh Sleep Quality Index (PSQI).

All patients (33 cases) were followed up for 12-38 months, with an average follow-up time of 23 months. On postoperative day 1, 31 patients (93.9%) reported no pain, and 2 patients were given drug treatment for pain relief, The total efficacy was 93.9%. Moreover, 2 patients (6.1%) reported significant pain relief 2 weeks postoperatively. There are many complications during and after PBC. The incidence of the trigeminocardiac reflex (TCR) during surgery was 100%, and the incidence of facial numbness, masseter muscle weakness, labial herpes and headache was 97, 60.6, 12.1 and 3%. No patient experienced severe facial numbness, hearing impairment, diplopia, injury to cranial nerves, Meningitis, intracranial haemorrhage or keratitis. 1 patient had recurrence of pain at 6 months post-op, which was relieved by oral medication. 81.8% suffered from anxiety and 54.5% had poor sleep quality before surgery. After the period of PBC, SAS and PSQI scores decreased continuously. There were significant improvements in anxiety and sleep status postoperatively compared with preoperatively.

PBC is a safe and effective option for the treatment of recurrent TN. The arduous and demanding nature of the clinical course subjects the patient to severe pain, mental, and physical stress. Thankfully, it significantly improves the symptoms of anxiety, depression, and sleep quality.

Trigeminal neuralgia (TN) is more prevalent among women. However, while microvascular decompression (MVD) is the most effective long-term surgical treatment for TN, it is unclear whether it is equally efficacious for men and women. We sought to characterize the relationship between sex and pain outcomes following MVD for TN.

From 2007 to 2020, 938 unilateral TN patients were treated with MVD at our institution. Patient demographics, clinical characteristics, operative features, and pain outcomes were recorded. Differences between men and women were analyzed via t-test and chi-squared analyses. A multivariate ordinal regression was used to establish significant predictors of pain outcome. Differences in time to pain recurrence were assessed via Cox proportional hazards and Kaplan-Meier nonparametric survival analysis.

A majority (67%) of the 938 patients analyzed were female. Men and women presented with similar preoperative pain severity (P = 0.17). Female sex (P = 0.048) and younger age (P = 0.03) were independently associated with worsened Barrow Neurological Institute pain scores at 3-month follow-up on multivariate analysis. Women were also more likely to experience recurrence than men (P = 0.01), and time to recurrence was shorter among women (P = 0.02). Only female sex was independently associated with increased risk of postoperative pain recurrence on multivariate Cox proportional hazards regression (P = 0.01).

Female TN patients undergoing MVD had worse pain outcomes, more frequent pain recurrence, and shorter time to recurrence. Our results indicate a sex-specific dimorphism in response to MVD among TN patients.

Trigeminal neuralgia is a rare and debilitating condition characterized by severe facial pain, often caused by the compression or irritation of the trigeminal nerve. Although trigeminal neuralgia caused by petrous bone lesions is uncommon, it can significantly impact a patient's quality of life. In this case report, we describe a 40-year-old female with a five-year history of severe facial pain diagnosed as trigeminal neuralgia. Imaging revealed an aneurysmal bone cyst in the petrous part of the left temporal bone, located near the trigeminal nerve's root entry zone. The patient underwent a successful left retrosigmoid craniotomy with the resection of the lesion, resulting in a significant improvement in her symptoms. At the six-month follow-up, the patient reported no recurrence of her symptoms and a considerable improvement in her quality of life. Although trigeminal neuralgia caused by an aneurysmal bone cyst in the left temporal bone is rare, surgery is the most effective treatment. Long-term outcomes are generally favorable with close follow-up. This case report highlights the importance of early diagnosis and timely surgical intervention in the management of this debilitating condition.

Microvascular decompression is safe, effective, and micro-invasive. Due to these advantages, it has become the mainstream treatment for trigeminal neuralgia, glossopharyngeal neuralgia, and hemifacial spasm. Initially, microvascular decompression was performed under a microscope, which limited the light source and visualization capabilities. With the development of endoscopic technology, the endoscope has been used in microvascular decompression, which further improved the visualization range and light source properties. The purpose of the present study was to investigate the efficacy of fully endoscopic microvascular decompression for the treatment of trigeminal neuralgia. In total, three patients with trigeminal neuralgia who underwent fully endoscopic microvascular decompression were evaluated. After surgery, the facial pain of all patients was significantly relieved. In addition, there were no obvious postoperative complications and no recurrence after 6 months of follow-up. These excellent surgical outcomes indicate that fully endoscopic microvascular decompression is an effective and safe method for the treatment of trigeminal neuralgia. Furthermore, it also shows that the endoscope presents advantages for use in microvascular decompression.

Ionizing radiation delivers sufficient energy inside the human body to create ions, which kills cancerous tissues either by damaging the DNA directly or by creating charged particles that can damage the DNA. Recent magnetic resonance (MR)-based conductivity imaging shows higher sensitivity than other MR techniques for evaluating the responses of normal tissues immediately after irradiation. However, it is still necessary to verify the responses of cancer tissues to irradiation by conductivity imaging for it to become a reliable tool in evaluating therapeutic effects in clinical practice. In this study, we applied MR-based conductivity imaging to mouse brain tumors to evaluate the responses in irradiated and non-irradiated tissues during the peri-irradiation period. Absolute conductivities of brain tissues were measured to quantify the irradiation effects, and the percentage changes were determined to estimate the degree of response. The conductivity of brain tissues with irradiation was higher than that without irradiation for all tissue types. The percentage changes of tumor tissues with irradiation were clearly different than those without irradiation. The measured conductivity and percentage changes between tumor rims and cores to irradiation were clearly distinguished. The contrast of the conductivity images following irradiation may reflect the response to the changes in cellularity and the amounts of electrolytes in tumor tissues.

In gamma knife radiosurgery, the tumor response to radiation is an important predictor of clinical treatment results. Since brain tumors have different characteristics and growth patterns, depending on the type, the tumors' response to radiation are also different. Compared with various other clinical treatments, there is a dearth of research on the development of gamma knife-magnetic resonance imaging (MRI) preclinical experimental equipment. Hence, the identification of preclinical equipment necessity for experimental animals will provide meaningful data for the provision of clinical assistance to humans.

A device for stereotactic radiosurgery capable of MRI in small animals was developed. The feasibility of creating a preplan by means of small animal images was then assessed.

A device for stereotaxic surgery of small animals using a 48-channel MRI coil was developed using a 3 dimensional printer. Rat brain-MRI images were obtained with a 3.0 T MRI scanner using a multi-channel coil. The acquired MRI images were transferred to a GammaPlan workstation to establish a preplan.

To gamma rays to the targeted site on animals, a positioning device combined with a G-frame was mounted on a gamma knife. Planning of radiosurgery based on MRI images became possible with GammaPlan workstations.

Preclinical experiments using small animals are possible with the use of stereotactic devices. In clinical treatment, preclinical experimental results will provide meaningful information.

Headache is a common presenting symptom in the ambulatory setting that often prompts imaging. The increased use and associated health care money spent in the setting of headache have raised questions about the cost-effectiveness of neuroimaging in this setting. Neuroimaging for headache in most cases is unlikely to reveal significant abnormality or impact patient management. In this article, reasons behind an observed increase in neuroimaging and its impact on health care expenditures are discussed. The typical imaging modalities available and various imaging guidelines for common clinical headache scenarios are presented, including recommendations from the American College of Radiology.

Trigeminal neuralgia (TN) is a chronic neuropathic pain condition affecting one or more divisions of the fifth cranial (trigeminal) nerve. TN is defined by recurrent unilateral electric shock-like pain that is abrupt in both onset and termination. The pain is triggered by innocuous sensory stimuli and is classified as either classic TN, related to vascular compression; secondary TN, due to a tumor along the trigeminal nerve or an underlying disease like multiple sclerosis; or idiopathic TN. Among the various therapies available for TN, carbamazepine remains the first-line treatment. Newer medications have demonstrated efficacy in patients who do not respond to or cannot tolerate carbamazepine. When medical management and neuroablative procedures fail, spinal cord stimulation (SCS) serves as a promising and popular option, with an estimated 34,000 SCS procedures performed annually worldwide. SCS employs the implantation of electrical leads in the epidural space to manage pain.

A review of literature was conducted to explore the use of cervical spinal cord stimulation (SCS) for the treatment of trigeminal neuralgia.

A MEDLINE/PubMed search using the search terms "spinal cord stimulation" and "trigeminal neuralgia" was employed to find any case reports and research studies (retrospective studies, double-blinded studies, observational studies) on the topic. No date limiters were used for the search. The initial search resulted in 76 non-duplicate entries from the database. After application of the search criteria, 58 studies were excluded because they were not relevant to the study. A further detailed review of the included articles was conducted by all the reviewers. During this phase of the review, additional 6 studies were excluded. A total of 11 studies were included: 7 case reports and 4 retrospective review studies.

In the review, we discuss 7 different case reports on the use of cervical SCS for trigeminal neuralgia and an additional 4 retrospective studies reviewing outcomes and pain relief in patients who underwent treatment. The case reports and retrospective studies reviewed demonstrated that TN patients realized > 50% pain relief following permanent electrode implantation. In all the cases discussed, complications from SCS were rare and/or not reported. Additionally, most of the cases report that patients who had adequate pain relief from SCS were able to wean off, or significantly reduce, oral medications given the vast improvement in pain reduction.

Cervical spinal cord stimulation (SCS) is a safe and effective procedure for patients with trigeminal neuralgia (TN) who have refractory pain despite the use of medications. In many cases, the procedure provides an adequate level of pain relief with very few complications or side effects. The vast majority of current research on the use of cervical SCS for TN currently consists of case reports and retrospective analysis. In order to further evaluate the efficacy of SCS for treatment, large-scale randomized controlled studies or observational studies need to be conducted to properly evaluate SCS as a treatment modality for trigeminal neuralgia.

Trigeminal neuralgia is a common condition that is associated with severe pain, which seriously affects the quality of life of patients. When the efficacy of drugs is not satisfactory or adverse drug reactions cannot be tolerated, minimally invasive interventional therapy has become an important treatment because of its simple operation, low risk, high repeatability and low cost. In recent years, minimally invasive interventional treatments, such as radiofrequency thermocoagulation (RF) of the trigeminal nerve and percutaneous microcompression (PMC), have been widely used in the clinic to relieve severe pain in many patients, however, some related problems remain to be addressed. The Pain Association of the Chinese Medical Association organizes and compiles the consensus of Chinese experts to standardize the development of minimally invasive interventional treatment of trigeminal neuralgia to provide a basis for its clinical promotion and application.

The Pain Association of the Chinese Medical Association organizes the Chinese experts to compile a consensus. With reference to the evidence-based medicine (OCEBM) system and the actual situation of the profession, the Consensus Development Committee adopts the nominal group method to adjust the recommended level.

Precise imaging positioning and guidance are the keys to ensuring the efficacy and safety of the procedures. RF and PMC are the most widely performed and effective treatments among minimally invasive interventional treatments for trigeminal neuralgia.

The pain degree of trigeminal neuralgia is severe, and a variety of minimally invasive intervention methods can effectively improve symptoms. Radiofrequency and percutaneous microcompression may be the first choice for minimally invasive interventional therapy.

To investigate the ability of magnetic resonance (MR) subtraction to evaluate neurovascular conflict (NVC) and to compare it with conventional MR protocols.

This prospective study included 82 patients with trigeminal neuralgia who underwent microvascular decompression for NVC. All patients had a pre-operative examination using 3T MRI. The MRI protocols used comprised 3D balanced (B)-fast field echo (FFE), 3D steady-state magnetic resonance angiography (MRA), and 3D T1-FFE sequences. MR subtraction images were obtained by subtracting native images from B-FFE and steady-state MRA. NVC evaluation was performed using subtraction images (MR subtraction) and combination images (conventional MR protocols using B-FFE and T1-FFE in combination). Clinical assessment of the degree of compression, the type of compressing vessel, and the location of conflict were undertaken by two independent observers. The two methods were then compared using surgical criteria.

MR subtraction exhibited greater accuracy than the conventional method in terms of the estimated severity of conflict (87.80% vs. 57.32%, p < 0.05), and demonstrated better consistency with surgical findings (k = 0.794 vs. k = 0.365, p < 0.05). For the type of compressing vessel and the location of conflict, both methods were highly accurate and agreed to a similar extent with surgical findings (p = 0.987, compressing vessel; p = 0.665, location of conflict).

MR subtraction proved reliable in NVC pre-operative evaluation, with increased accuracy when estimating severity. This result strongly supports the wider use of MR subtraction as the preferred choice in clinical application.

Characterized by the coexistence of trigeminal neuralgia and ipsilateral hemifacial spasm (HFS), painful tic convulsif (PTC) is a rare entity that has not yet been systematically studied.

To systematically explore the epidemiology, cause, prognosis, and prognosis predictors of PTC.

We searched PubMed, Web of Science, and the Cochrane Library for relevant studies published between establishment of the library and July 1, 2020. Information on demographics, causes, specific interventions, and intervention outcomes was extracted. We first performed descriptive analysis of demographics, causes, and surgical outcomes of PTC. Univariate and multivariate regression methods were used to explore potential prognosis predictors. Further, a 2-step meta-analysis method was used to validate the identified factors.

Overall, 57 reports including 192 cases with PTC were included in the analysis. The median age of patients with PTC is 54 years (range, 44-62 years), with more patients being female (P < 0.001), initiated as HFS (P = 0.005), and being affected with left side (P = 0.045). The vertebrobasilar artery contributes to >65% of the causes of single vascular compression for PTC. Anterior inferior cerebellar artery/posterior inferior cerebellar artery involvement (odds ratio, 4.050; 95% confidence interval, 1.091-15.031) and older age (P = 0.008) predict freedom from symptoms and recurrence after microvascular decompression, respectively.

PTC occurs more in middle-aged women between 40 and 60 years old, initiates as HFS, and affects the left side. Vertebrobasilar artery compression is the most common single cause of PTC. Microvascular decompression effectively treated PTC, with a cure rate >80%. Anterior inferior cerebellar artery/posterior inferior cerebellar artery involvement predicts successful surgery and older age predicts recurrence.

Trigeminal neuralgia (TN), the most common form of severe facial pain, may be confused with an ill-defined persistent idiopathic facial pain (PIFP). Facial pain is reviewed and a detailed discussion of TN and PIFP is presented. A possible cause for PIFP is proposed. (1) Methods: Databases were searched for articles related to facial pain, TN, and PIFP. Relevant articles were selected, and all systematic reviews and meta-analyses were included. (2) Discussion: The lifetime prevalence for TN is approximately 0.3% and for PIFP approximately 0.03%. TN is 15-20 times more common in persons with multiple sclerosis. Most cases of TN are caused by neurovascular compression, but a significant number are secondary to inflammation, tumor or trauma. The cause of PIFP remains unknown. Well-established TN treatment protocols include pharmacotherapy, neurotoxin denervation, peripheral nerve ablation, focused radiation, and microvascular decompression, with high rates of relief and varying degrees of adverse outcomes. No such protocols exist for PIFP. (3) Conclusion: PIFP may be confused with TN, but treatment possibilities differ greatly. Head and neck muscle myofascial pain syndrome is suggested as a possible cause of PIFP, a consideration that could open new approaches to treatment.

Trigeminal neuralgia is featured by episodic and severe unilateral facial pain triggered usually by innocuous cutaneous stimuli.^1-4 Microvascular decompression (MVD) is a safe and effective treatment for cases refractory to medical treatment caused by neurovascular conflicts.^1,5-7 This Video 1 demonstrates MVD using arachnoid membrane and petrosal dura to transpose dual offending arteries. Informed consent was obtained from the patient for publication of this operative video. The patient was a 64-year-old woman with refractory right trigeminal neuralgia (V2 territory). Preoperative magnetic resonance imaging demonstrated simultaneous conflict between the right trigeminal nerve (TN) and superior cerebellar (SCA) and anterior inferior cerebellar arteries (AICA). Due to progressive and refractory symptoms, MVD was indicated, with aid of neurophysiologic monitoring. A right retrosigmoid approach was employed and after exposure of the TN root, both AICA and SCA were identified conflicting with the nerve. The AICA was displaced inferolaterally and attached to the petrosal dura between the VII/VIII and IX cranial nerves using a USP #0 silk thread. The SCA was mobilized into a fissure created in the lateral pontomesencephalic arachnoid membrane and fixed with shredded Teflon (polytetrafluoroethylene). Another piece of Teflon was positioned between the TN and the proximal segment of AICA to lighten the pulling force from the thread. Postoperative imaging demonstrated no signs of cerebellar contusion or hemorrhage. The patient presented complete resolution of her pain, and no neurologic deficits were observed. We demonstrate MVD with 2 different transposition techniques that can be considered for trigeminal neuralgia with dual offending arteries (AICA, SCA).

Changes in blood pressure during trigeminal combing have been discussed in recent years. In this study, a retrospective analysis of patients with trigeminal neuralgia (TN) requiring microvascular decompression (MVD) with nerve combing was carried out to investigate fluctuation in arterial blood pressure during trigeminal nerve combing and its surgical effect and corresponding pathogenesis.

A total of 70 cases of MVD with nerve combing performed during the treatment of primary TN patients were selected between January 2017 and January 2018 at Peking University People's Hospital. The degree of pain and prognosis of the patients were evaluated according to the visual analog scale. Postoperative facial numbness of the 2 groups were assessed by the Barrow Neurological Institute facial numbness score. Arterial blood pressure changes before and while combing the trigeminal nerve during MVD were dynamically monitored, and the patients were divided into responders and nonresponders. Total adrenaline (AD), norepinephrine (NE), and dopamine values were measured before and during trigeminal nerve combing.

Increased arterial blood pressure during the combing of the trigeminal nerve in MVD had a significant correlation with the prognosis of patients, with patients with higher arterial blood pressure having a better prognosis (P < 0.05). In the increased arterial blood pressure patients, precombing total AD and NE means were dramatically improved (P < 0.05).

This study shows that changes in arterial blood pressure during trigeminal nerve combing in MVD were correlated with the prognosis of patients. Further research is necessary to clarify the mechanism of increased arterial blood pressure.

Seven-Tesla (7T) magnetic resonance imaging (MRI) has demonstrated value for evaluating a variety of intracranial diseases. However, its utility in trigeminal neuralgia has received limited attention. The authors of the present study applied ultra-high field multimodal MRI to two representative patients with secondary trigeminal neuralgia due to epidermoid tumors to illustrate the possible clinical and surgical advantages of 7T compared with standard clinical strength imaging. Techniques included co-registration of multiple 7T sequences to optimize the detection of potential concurrent neurovascular and neoplasm-derived compression.

7T MRI studies were performed using a whole body scanner. Two- and three-dimensional renderings of potential neurovascular conflict were created by co-registering time-of-flight angiography and T2-weighted turbo spin echo images in MATLAB and GE software. Detailed comparisons of the various field strength images were provided by a collaborating neuroradiologist (B.D.).

7T MRI clearly illustrated minute tumor-adjacent vasculature. In contrast, conventional, low-field imaging did not consistently provide adequate details to distinguish cerebrospinal fluid pulsatility from vessels. The tumor margins, although distinct from the trigeminal nerve fibers at 7T, blended with those of the surrounding structures at 3T. Two- and three-dimensional co-registration of time-of-flight angiography with T2-weighted MRI suggested that delicate, intervening vasculature may have contributed to these illustrative patients' symptomatology.

7T provided superior visualization of vital landmarks and subtle nerve and vessel features. Co-registration of various advanced 7T modalities may help to resolve complex disease etiologies. Future studies should explore the extent to which this dual etiology might persist across tumor types and utilize diffusion-based techniques to quantify what microstructural differences might exist between patients with trigeminal neuralgia from varying etiologies.