Sacrifice or preserve the superior petrosal vein in microvascular decompression surgery

J Neurosurg 138:390–398, 2023

In microvascular decompression (MVD) surgery through the retrosigmoid approach, the surgeon may have to sacrifice the superior petrosal vein (SPV). However, this is a controversial maneuver. To date, high-level evidence comparing the operative outcomes of patients who underwent MVD with and without SPV sacrifice is lacking. Therefore, this study sought to bridge this gap.

METHODS The authors searched the Medline and PubMed databases with appropriate Medical Subject Heading (MeSH) terms and keywords. The primary outcome was vascular-related complications; secondary outcomes were new neurological deficit, cerebrospinal fluid (CSF) leak, and neuralgia relief. The pooled proportions of outcomes and OR (95% CI) for categorical data were calculated by using the logit transformation and Mantel-Haenszel methods, respectively.

RESULTS Six studies yielding 1143 patients were included, of which 618 patients had their SPV sacrificed. The pooled proportion (95% CI) values were 3.82 (0.87–15.17) for vascular-related complications, 3.64 (1.0–12.42) for new neurological deficits, 2.85 (1.21–6.58) for CSF leaks, and 88.90 (84.90–91.94) for neuralgia relief. The meta-analysis concluded that, whether the surgeon sacrificed or preserved the SPV, the odds were similar for vascular-related complications (2.5% vs 1.5%, OR [95% CI] 1.01 [0.33–3.09], p = 0.99), new neurological deficits (1.2% vs 2.8%, OR [95% CI] 0.55 [0.18–1.66], p = 0.29), CSF leak (3.1% vs 2.1%, OR [95% CI] 1.16 [0.46–2.94], p = 0.75), and neuralgia relief (86.6% vs 87%, OR [95% CI] 0.96 [0.62–1.49], p = 0.84).

CONCLUSIONS SPV sacrifice is as safe as SPV preservation. The authors recommend intentional SPV sacrifice when gentle retraction fails to enhance surgical field visualization and if the surgeon encounters SPV-related neurovascular conflict and/or anticipates impeding SPV-related bleeding.


Individual variations of the superior petrosal vein complex and their microsurgical relevance in 50 cases of trigeminal microvascular decompression

Acta Neurochirurgica (2020) 162:197–209

We investigated the understudied anatomical variations of the superior petrosal vein (SPV) complex (SPVC), which may play some role in dictating the individual complication risk following SPVC injury.

Methods Microvascular decompressions of the trigeminal nerve between September 2012 and July 2016. All operations utilized an SPVC preserving technique. Preoperative balanced fast field echo (bFFE) magnetic resonance imaging, or equivalent sequences, and operative videos were studied for individual SPVC anatomical features.

Results Applied imaging and operative SPVC anatomy were described for fifty patients (mean age, 67.18 years; female sex and right-sided operations, 58% each). An SPVC component was sacrificed intentionally in 6 and unintentionally in only 7 cases. Twenty-nine different individual variations were observed; 80% of SPVCs had either 2 SPVs with 3 or 1 SPV with 2, 3, or 4 direct tributaries. Most SPVCs had 1 SPV (64%) and 2 SPVs (32%). The SPV drainage point into the superior petrosal sinus was predominantly between the internal auditory meatus and Meckel cave (85.7% of cases). The vein of the cerebellopontine fissure was the most frequent direct tributary (86%), followed by the pontotrigeminal vein in 80% of SPVCs. Petrosal-galenic anastomosis was detected in at least 38%of cases. At least 1 SPVin 54%of the cases and at least 1 direct tributary in 90%disturbed the operative field. The tributaries were more commonly sacrificed.

Conclusions The extensive anatomical variation of SPVC is depicted. Most SPVCs fall into 4 common general configurations and can usually be preserved. BFFE or equivalent sequences remarkably facilitated the intraoperative understanding of the individual SPVC in most cases.

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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