Tag: Neurovascular conflict

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How I do it: microvascular decompression for vago-glossopharyngeal neuralgia

Acta Neurochirurgica (2026) 168:62

This surgical how-to describes microvascular decompression (MVD) for vago‑glossopharyngeal neuralgia, detailing patient selection, imaging requirements, anesthesia, positioning, and a retrosigmoid infrafloccular approach to expose the IX–X root entry zones. It emphasizes preoperative high-resolution MRI identification of neurovascular conflict—most often PICA or vertebrobasilar compression—and perioperative neurophysiological monitoring.

The technique section outlines stepwise microsurgical maneuvers: arachnoid dissection, vessel mobilization or transposition, cautious Teflon interposition when needed, hemostasis, watertight closure, and targeted postoperative surveillance for dysphagia, hoarseness, CSF leak, and other complications. Practical tips for avoiding complications and key informed‑consent elements are provided.

Vago-Glossopharyngeal Neuralgia (VGN): Rare craniofacial pain syndrome (<1% of facial pain cases), often caused by neurovascular conflict involving the posterior inferior cerebellar artery (PICA) and sometimes the vertebrobasilar artery.

Clinical Features: Characterized by paroxysmal, lancinating pain in the oropharynx, tonsillar fossa, base of tongue, or deep ear canal, typically triggered by swallowing, talking, or coughing.

Diagnosis: High-resolution MRI (T2-weighted CISS/FIESTA/DRIVE, 3D TOF angiography) is mandatory to demonstrate neurovascular conflict and guide surgical planning.

First-line Surgical Treatment: Microvascular decompression (MVD) is the most effective and durable option for drug-refractory VGN, aiming to relieve neurovascular conflict without damaging nerve rootlets.

Surgical Approach: Keyhole retrosigmoid craniectomy with infrafloccular approach exposes the root entry zone of cranial nerves IX and X; careful arachnoid dissection and vessel mobilization or Teflon interposition are performed.

Intraoperative Considerations: Intraoperative neuromonitoring of lower cranial nerves is recommended to minimize risk of postoperative deficits such as dysphagia or hoarseness.

Complications: Main risks include transient dysphagia, hoarseness, or lower cranial nerve palsies, which are usually temporary and resolve within three months.

Outcomes: MVD offers superior and lasting pain relief with functional preservation compared to ablative procedures, making it the preferred surgical option.

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The correlation study between posterior fossa crowding and classical trigeminal neuralgia

Acta Neurochirurgica (2025) 167:14

Objective To explore the correlation between posterior fossa crowding and the occurrence of classical trigeminal neuralgia (TN).

Methods A total of 60 patients diagnosed with classical TN and 60 age- and sex-matched healthy volunteers were included as a control group for a case-control study. All subjects underwent high-resolution 3D magnetic resonance imaging (MRI) examinations (including 3D-FIESTA and 3D-TOF MRA sequences). The original data were subjected to 3D reconstruction and measurement of posterior fossa volume (PFV) and hindbrain volume (HBV) using 3D-slicer software. The posterior fossa crowding index (PFCI) was calculated as HBV/PFV × 100%. Finally, data were analyzed using SPSS 22.0 statistical software.

Results The average PFCI in patients with TN was 85.0% ± 3.9%, compared to 82.7% ± 3.9% in the control group, with a significant statistical difference (P = 0.025). Female patients with TN had a more crowded posterior fossa than male patients (86.4% ± 3.8% vs. 83.4% ± 3.4%, P = 0.033). Multiple linear regression analysis showed that a higher PFCI was associated with being female (P = 0.022), younger age (P = − 0.003), and being a patient with TN (P = − 0.023).

Conclusion Patients with PTN have a more crowded posterior fossa compared to the healthy control group. A higher PFCI is associated with being female, younger age, and being a patient with TN. Posterior fossa crowding may be a risk factor for neurovascular conflict (NVC), making it more likely to lead to the occurrence of TN.

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Arachnoiditis as an outcome factor for microvascular decompression in classical trigeminal neuralgia

Acta Neurochirurgica (2019) 161:1589–1598

Neurovascular conflict is considered a key element of classical trigeminal neuralgia (TN) and consequently, mi- crovascular decompression (MVD) is an effective treatment. Nevertheless, failures of MVD are described by many authors. In some patients, the arachnoid membranes surrounding the trigeminal nerve and neighbouring vessels may be thickened and adhesive. Here we analyse the impact of such focal arachnoiditis on outcome after MVD for TN.

Methods A cohort of prospectively followed patients after their MVD was reviewed for intraoperative, imaging and clinical data if findings of arachnoiditis during MVD were described. Long-term outcome assessment was the main endpoint.

Results We reviewed data from 395 MVD procedures, performed for TN from 2001 to 2014. Intraoperative evidence of focal arachnoiditis, as described by the surgeon, has been noted in 51 patients (13%). In 35 (68.6%), neuralgia was typical and in the other 17 (31.4%) it was atypical.
As expected by definition, neurovascular conflict was found in 49 interventions (96%); it was predominantly arterial in 27 (52.9%). Accompanying arachnoiditis was encountered: mild in 20 interventions (39.2%), severe in 31 (60.8%).
A successful result (BNI I or II) was achieved in 29 patients (56.9%). The other 22 patients (43.1%) had persistence or recurrence of pain. Overall KM probability of being pain free at 15 years was 72%.

Conclusions Intraoperative finding of arachnoiditis during MVD for classical trigeminal neuralgia is associated with poorer outcome than that of classical trigeminal neuralgia in general. This is particularly true for low grades of conflict.

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Nerve atrophy in trigeminal neuralgia due to neurovascular compression and its association with surgical outcomes after microvascular decompression

Acta Neurochir (2017) 159:1699–1705

Idiopathic trigeminal neuralgia (TN) is caused by neurovascular compression and is often related to morphological changes in the trigeminal nerve. The aim of this study was to quantitatively measure atrophic changes of trigeminal nerves in patients with TN, and to further investigate whether nerve atrophy affected the efficacy of microvascular decompression (MVD).

Methods We conducted a prospective case-control study of 60 consecutive patients with TN and 30 sex- and age-matched healthy controls. All subjects underwent high-resolution three-dimensional MRI. The volume of the cisternal segment of trigeminal nerves was measured and compared using 3D Slicer software. Patients with TN underwent primary MVD and regular follow-up for at least 2 years. Associations of nerve atrophy with patient characteristics and operative outcomes were analyzed.

Results The mean volume of the affected trigeminal nerve was significantly reduced in comparison to that of the nonaffected side (65.8 ± 21.1 versus 77.9 ± 19.3 mm3, P = 0.001) and controls (65.8 ± 21.1 versus 74.7 ± 16.5 mm3, P = 0.003). Fifty-two patients (86.7%) achieved complete pain relief without medication immediately after surgery, and 77.6% of patients were complete pain relief at the 2-year follow-up. The Spearman correlation test showed that there was a positive correlation (r=0.46, P = 0.018) between the degree of trigeminal nerve indentation and nerve atrophy. In multivariate logistic regression analysis, two factors, indentation on nerve root (OR = 2.968, P = 0.022) and degree of nerve atrophy (OR = 1.18, P = 0.035), were associated with the long-term outcome.

Conclusions TN is associated with atrophy on the affected nerve. Furthermore, greater nerve atrophy is associated with more severe trigeminal nerve indentation and better long-term outcome following MVD.

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Trigeminal neuralgia due to venous neurovascular conflicts

Acta Neurochir (2017) 159: 237

Implication of veins as neurovascular conflict (NVC) in the genesis of trigeminal neuralgia (TN) remains a matter of debate. Few reports dealing with venous NVC have been published. The objective of this study is to describe the outcome in a historical cohort of consecutive patients with classical TN due to venous compression.

Methods: All patients with TN treated by microvascular decompression (MVD) from 2005 to 2013 were included if a marked venous compression was found at the surgery either alone or accompanied by an artery. Patients were evaluated for clinical presentation, operative findings and the long-term outcome. Outcome was considered favourable if patients were classed as BNI I or II (i.e. not requiring any medication). Kaplan-Meier analysis was used to determine probability of a favourable outcome at 10 years of follow-up.

Results:  Out of the overall series of 313 patients having been treated by MVD and considered for the study, in 55 (17.5 %) a vein was the main compressive vessel; in 26 (8.3 %) it was the only compressive vessel. Probability of relief with no need for medication at 10 years was 70.6 %. The patients with focal arachnoiditis had a poor long-term outcome, i.e. BNI III-V, in 85.7 % compared with 20.8 % without arachnoiditis (p = 0.0037 Fisher’s exact test). No differences in outcome were found between patients presenting with purely venous compression and patients with mixed compression. Outcome was similarly good for patients with atypical neuralgia when compared to patients with typical clinical presentation.

Conclusions: Venous NVC as a cause of TN is far from rare. MVD with complete liberation of the entire root in cases with clear-cut venous compression on imaging studies gives a good probability of long-term pain relief, thus encouraging to propose surgery for such patients.

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Trigeminal neuralgia due to neurovascular conflicts from venous origin: an anatomical-surgical study

Trigeminal neuralgia due to neurovascular conflicts from venous origin- an anatomical-surgical study-1

Acta Neurochir (2015) 157:455–466

Veins as the source of trigeminal neuralgias (TN) lead to controversies. Only a few studies have specifically dealt with venous implication in neurovascular conflicts (NVC). The aim of this study was the anatomical-surgical description of the compressive veins found during microvascular decompression (MVD).

Methods Patients retained were those in whom a vein was considered compressive, alone, or in association with an artery. The study defined the type of vein involved, its situation along, the location around the root, and management. For this study, denomination of veins in relation with the root was revisited.

Results Of the 326 consecutive patients who underwent MVD from 2005 to 2013, 124 (38.0 %) had a venous conflict, alone in 29 (8.9 %), or in association with an artery in 95 (29.1 %). The compressive veins belonged to one of the two venous systems described: the superficial or the deep superior petrosal venous system (sSPVS or dSPVS). A vein from sSPVS was found compressive in 81 cases (59.6 %), for the major part it was the pontine affluent of the superior petrosal vein (48 cases). The conflict was situated at TREZ in 28.4 %, midcisternal portion in 50.6 %, and porus in 8.6 %. The dSPVS was found compressive in 55 cases (40.4 %), almost always a transverse vein at porus (51 cases). Decompression was coagulation-division of the conflicting vein in 36.8 % and simple cleavage in the other.

Conclusions The study shows the frequent implication of veins in NVC as the source of TN. NVC are not only at TREZ but also at mid-cisternal portion and porus of Meckel cave.

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