Trigeminal neuralgia (TN), a severe facial pain condition, is often treated with microvascular decompression (MVD). While MVD is effective for arterial neurovascular compression, its efficacy in cases of venous compression and the intraoperative management of such cases remain areas of debate. This review aimed to analyze the intraoperative management strategies for offending veins during MVD and evaluate the outcomes of these procedures in cases of TN with purely venous compression. An extensive review of studies reporting on the intraoperative handling of veins and the surgical outcomes of MVD in purely venous compression cases was conducted. Fifteen full-text studies were included, encompassing a total of 600 patients. Notably, 82.33% of these patients achieved a Barrow Neurological Institute (BNI) I pain score, with follow-up periods ranging from 3 months to 12 years. MVD is a viable and effective treatment option for TN in cases of venous compression, with a significant proportion of patients experiencing substantial pain relief.

UNASSIGNED: To evaluate the prevalence of vascular contact of the facial nerve in patients without hemifacial spasm or facial palsy using magnetic resonance imaging (MRI).
UNASSIGNED: Our radiology database was accessed to find a series of consecutive adult patients who underwent MRI of the brain during the study period, excluding those with a history of hemifacial spasm (HFS), facial palsy, traumatic brain injury, intracranial tumour, intracranial surgery, trigeminal neuro-vascular compression, brain radiation therapy, and studies with poor image quality. A total of 112 (224 sides) MRIs of the posterior fossa were independently reviewed by 2 radiologists for neurovascular contact involving the facial nerve. The presence of neuro-vascular contact, the number of points of contact, the location of contact along the intracranial course of the facial nerve, the culprit vessel, and the severity of compression were recorded in the CISS MRI sequence in the cohort of patients without HFS and facial palsy.
UNASSIGNED: The prevalence of neurovascular contact involving the facial nerve can be as high as 51% in patients asymptomatic for HFS and facial palsy. It is frequently caused by the anterior inferior cerebellar artery and commonly involves the cisternal portion with mild to moderate severity.
UNASSIGNED: In asymptomatic patients, the pulsatile neurovascular contact of the intracranial segment of the facial nerve typically occurs at one point, involving the distal portion with milder severity in contrast to patients with HFS. These results in the asymptomatic cohort should be considered when evaluating the candidacy of HFS patients for microvascular decompression.

UNASSIGNED: This study aims to evaluate the effectiveness of Magnetic Resonance Virtual Endoscopy combined with 3D-FIESTA-c and 3D-TOF-MRA in preoperative assessment of MVD for PTN, with a focus on accurately detecting neuromuscular contact.
UNASSIGNED: We retrospectively analyzed clinical and imaging data from 240 patients with unilateral primary trigeminal neuralgia undergoing MVD surgery between April 2016 and July 2023. Preoperative scans with 3D-FIESTA-c and 3D-TOF-MRA were performed, and MRVE images were obtained to analyze the relationship between the trigeminal nerve and adjacent vessels. Using the findings during microvascular decompression (MVD) surgery as the gold standard, the diagnostic results of 3D-TOF-MRA + 3D-FIESTA-c were considered as group I, while the combined use of MRVE, 3D-TOF-MRA + 3D-FIESTA-c was considered as group II.
UNASSIGNED: In 240 cases, group I had a positive rate of 96.25% and an accuracy rate of 86.25% for identifying responsible blood vessels, while group II had a positive rate of 98.3% and an accuracy rate of 94.17%. There were no statistically significant differences in positive rates between group I and group II, group I and MVD, or group II and MVD (P > 0.05). However, there were statistically significant differences in accuracy rates (P < 0.05). The accuracy for single and multiple arteries with group I was 99.38% and 80.0%, respectively, while with group II, it was 100% and 95.0%. No statistically significant difference was found in accuracy for single or multiple arteries (P>0.05). The accuracy of evaluating responsibility veins with or without other vessels was 52.73% and 80.0%, respectively, with a statistically significant difference (P<0.05).
UNASSIGNED: MRVE combined with 3D-TOF-MRA + 3D-FIESTA-c significantly improves the accuracy of identifying responsibility vessels, especially veins, in preoperative assessment for MVD. This has important clinical implications for preoperative decision-making and surgical planning.

OBJECTIVE: This study aimed to review our experience with patients who suffered from recurrent trigeminal neuralgia (TN) and underwent repeat microvascular decompression surgery (rMVD).
METHODS: This observational study is based on retrospective analysis and was conducted at the Department of Neurosurgery in a university hospital. It included patients who initially experienced complete pain relief after the first MVD but later had a recurrence of TN symptoms and subsequently underwent rMVD. Pain control outcomes were evaluated based on the Barrow Neurological Institute (BNI) scale score.
RESULTS: Out of a total of 375 patients who underwent MVD for TN over a 20-year period, 19 patients (6 females, 13 males) with a mean age of 57.68 ± 9.78 years suffered from recurrent symptoms necessitating rMVD (%5.06). The average duration of symptoms before rMVD was 16.1 ± 19.36 months. The mean BNI score of the patients before rMVD was 4.5 ± 0.5. recurrence was primarily attributed to compression by a new offending vessel (n=9, 47.4%) and Teflon granuloma formation (n=8, 42.1%). Two patients (10.5%) showed no compression. During a follow-up period of 106.3 ± 58.3 months, excellent pain relief (BNI-I) was achieved in 10 patients (52.6%). Eight patients (42.1%) experienced a good outcome (BNI-III), while one patient (5.3%) had a poor outcome (BNI-IV).
CONCLUSIONS: Recurrence of TN symptoms can occur even after initially successful MVD procedures. Repeat MVD should be considered as the primary treatment option in recurrent cases, as it can lead to significant pain control with low morbidity.

The coincidence in a patient of Hemifacial Spasm and Trigeminal Neuralgia is not frequent. A case is presented with the objective of showing this association due to the abnormal activation of the Trigemino-Facial Reflex. A 55-year-old woman with an 8-year history of left-sided hemifacial spasm and typical trigeminal pain in the ipsilateral V1 and V2 territory. The physical examination shows spasms in the left hemiface, with reproduction of intense pain upon sensory stimulation of the skin on the forehead and upper dental arch. The MRI showed a vessel in intimate contact with the entrance area of ​​the left trigeminal nerve. A left retrosigmoid approach was performed. First, the entrance area of ​​the trigeminal nerve was accessed, finding a clear vascular conflict, which was isolated with Teflon. Then, the trajectory was changed and the exit zone of the facial nerve was accessed, and no type of vascular conflict was identified. The patient presented complete resolution of the Hemifacial Spasm and the associated trigeminal pain. The analysis of this case allows us to conclude that during microvascular decompression of the Facial Nerve, if frank proximal compression is not evident, the Trigeminofacial structural relationship must be taken into account, making it necessary to explore the Trigeminal Nerve.

OBJECTIVE: To compare whether there is a difference in the efficacy of complete endoscopic microvascular decompression (EVD) and microscopic microvascular decompression (MVD) in patients with classical trigeminal neuralgia (CTN).
METHODS: From January 2014 to January 2021, 297 CTN patients were assigned to the retrosigmoid approach EVD (138 cases) and the MVD groups (159 cases); to compare whether there are differences in the pain control rate, recurrence, complications of CTN patients between the 2operations, and separately predict the factors related to prognosis of both groups.
RESULTS: There was no significant difference in painless rates at 1, 3, and 5 years after surgery (P = 0.356, P = 0.853, P = 1), and overall incidence of complications (P = 0.058) between the EVD and MVD groups. The EVD group had shorter surgical decompression duration than the MVD group (P < 0.001). The painless rate of patients with vertebrobasilar trigeminal neuralgia in the EVD group was higher than that in the MVD group, but the difference was not statistically significant (90% vs. 61.1%, P = 0.058). The independent risk factors associated with a good prognosis in the EVD group were a shorter course of the disease and severe neurovascular conflict, while severe neurovascular conflict is the only independent risk factor associated with a good prognosis in the MVD group.
CONCLUSIONS: For CTN patients, compared with traditional MVD, EVD is also safe and effective and has the advantage of shorter decompression time.The predictive results of prognostic factors also suggest that CTN patients may benefit more from early surgical treatment.

Vestibular paroxysmia (VP) is a rare condition. The pathogenesis is linked to a neurovascular conflict (NVC) between an abnormal arterial loop and the VII/VIII cranial nerve complex in the cerebello-pontine angle. Due to its rarity, intraoperative findings are only anecdotally reported. Here we reported on a case of VP, showing the radiological images and the intraoperative surgical video of microvascular decompression (MVD). Further we discussed our findings considering the pertinent literature. We think that in case of VP the concordance between the side of tinnitus/hypoacusia and the side of NVC on magnetic resonance imaging should be always looked for before considering MVD as a therapeutic option.

OBJECTIVE: Trigeminal neuralgia (TN) due to venous compression is far less common than that due to arterial compression, and its pathogenesis is less clear. We investigated the clinical and imaging features of TN caused by solely venous compression by measuring the morphologies of the posterior cranial fossa (PCF) and the trigeminal nerve.
METHODS: We retrospectively reviewed records of TN patients who underwent microvascular decompression at our institution and extracted cases with solely arterial or solely venous compression. Preoperative magnetic resonance imaging was used to find the length (Y), width (X), height (Z), and volume (V) of the PCF, the angle between the trigeminal nerve and pons, and the distance between Meckel\'s cave and the root entry zone of the trigeminal nerve.
RESULTS: Of 152 patients, 24 had TN caused solely by venous compression. The value of Y was significantly smaller in the venous group than the arterial group (P < 0.01). The trigeminal nerve and pons was significantly smaller in the venous group (P < 0.01). We hypothesized that TN patients with solely venous compression had a characteristic PCF morphology with a short anteroposterior diameter (Y), such that age-related changes in brain morphology could alter the course of the trigeminal nerve and cause compression by a vein.
CONCLUSIONS: The morphological features of the PCF differed between patients with TN of venous and those with TN of arterial etiology. Age-related changes in brain morphology and changes of course of the trigeminal nerve may also add to the possibility of developing TN, especially of venous etiology.

Neurovascular compression (NVC) syndromes such as trigeminal neuralgia (TN) are causally treated with microvascular decompression (MVD). Semiautomatic segmentation of high-resolution magnetic resonance imaging (MRI) data and constructive interference in steady state (CISS)/time-of-flight (TOF) sequences are utilized for the three-dimensional (3D) visualization of underlying causative vessels at the root entry zones of the relevant cranial nerves. Augmented reality (AR) of neurovascular structures was introduced especially in the resection of brain tumors or aneurysmatic operations. In this report, the potential feasibility of the implementation of microscope-based AR into the intraoperative microsurgical set-up of MVD was investigated. This article recommends the preoperative evaluation of 3D visualization besides the microscopical view of the surgeon. The implementation of multiple imaging data by AR into the operating microscope may afflict the experienced surgeon\'s view, which should be examined prospectively.

OBJECTIVE: The trigeminocardiac reflex (TCR) has traditionally been characterized by a sudden decrease in heart rate, asystole, or hypotension during the manipulation of the trigeminal nerve (MTN) or its branches. While this classical TCR is well-documented, there is limited literature on alternative forms of TCR, such as the development of intraoperative hypertension (HTN) or tachycardia, and the underlying pathogenesis. Furthermore, a gap exists in understanding the correlation between intraoperative blood pressure readings and postoperative outcomes, particularly regarding pain relief in patients with trigeminal neuralgia (TN). Our study aims to examine intraoperative blood pressure trends during microvascular decompression (MVD) for TN and assess their impact on postoperative outcomes.
METHODS: We selected 90 patients who underwent MVD for TN treatment. Blood pressure and heart rate were recorded both preoperatively and during the procedure, specifically during the MTN period, using an arterial line. The Barrow Neurological Institute (BNI) Pain Scale was calculated for all patients both pre- and post-operatively to evaluate pain relief after surgery.
RESULTS: The mean age of the patients was 61.0 ± 12.35 years, with 64.4% being females. Classical TCR (hypotension) was observed in only 2.2% of patients, whereas 80% of patients developed hypertension (≥ 140/90) during MTN. The mean preoperative systolic blood pressure was 128 ± 22.25, and the mean intraoperative systolic blood pressure during MTN was 153.1 ± 20.2. An analysis of covariance, utilizing either preoperative BNI or duration of symptoms as covariate variables, revealed a statistically significant association between intraoperative HTN and postoperative BNI. A linear regression model demonstrated that intraoperative HTN following MTN significantly predicted a lower postoperative BNI score (p = 0.006).
CONCLUSIONS: Intraoperative HTN during MTN, an observed yet underexplored phenomenon, demonstrated a correlation with improved postoperative outcomes. Furthermore, it is recommended to conduct additional investigations into potential neurovascular conflicts in patients not manifesting intraoperative HTN following MTN. A comprehensive understanding of TCR, encompassing its various forms, is vital for optimizing surgical management. This study underscores the imperative for further research to unravel the mechanisms linking intraoperative HTN to surgical outcomes in TN patients.