Efficacy of microvascular decompression in patients with trigeminal neuralgia with negative neurovascular relationship shown by magnetic resonance tomography.

OBJECTIVE: To explore the surgical efficacy of microvascular decompression(MVD) when the recent magnetic resonance tomography angiography(MRA) is unable to determine the relationship between blood vessels and nerves in patients with trigeminal neuralgia(TN). MATERIALS AND METHODS: The MRI images of 146 patients with TN who underwent MVD from January 2016 to December 2019 were analyzed retrospectively. The relationship between nerves and vessels was categorized as no contact, suspicious contact, and clear contact. Suspicious contact and clear contact were both defined as positive neurovascular relationship, whereas no contact was defined as negative neurovascular relationship. The efficacy of MVD in positive and negative groups was compared. RESULTS: 1. A total of 146 TN patients underwent MVD. Intraoperative examination revealed that out of 146, 143 patients exhibited contacts, including 110 cases with arterial contact, 22 cases with combined arterial and venous contact, and 11 cases with venous contact. Considering the surgical result as a gold standard, the sensitivity of three-dimensional time leap angiography (3D-TOF-MRA) in assessing vascular compression in TN was 74.0 %; and the sensitivity of three-dimensional steady-state precession rapid imaging sequence (3D-FIESTA) in determining vascular compression was 82.2 %. Out of a total of 17 cases demonstrating negative neurovascular relationship by 3D-TOF-MRA together with 3D-FIESTA, 14 cases were found to have vascular contact during the surgery, and the sensitivity was determined to be 88.4 %. 2.Among the 38 patients with a negative neurovascular relationship demonstrated by 3D-TOF, postoperative efficacy was noted as a cure: 30 cases, improved: 5 cases, no effect: 3 cases. 3D-FIESTA showed 26 cases of negative neurovascular relationship, among them, cured: 20 cases, improved: 3 cases, no effect: 3 cases. A total of 17 patients with negative neurovascular relationships were established by 3D-TOF-MRA together with 3D-FIESTA, and the postoperative effects were found to be cure: 13 cases, improvement: 2 cases, and no effect: 2 cases. There was no statistically significant difference between the negative group and the positive group (x2 test; p > 0.05). CONCLUSION: To conclude, 3D-TOF-MRA, together with 3D-FIESTA, can illustrate the large blood vessels surrounding the trigeminal nerve efficiently, and determine whether it is the offending blood vessel. The interpretation would help reproduce the local anatomical spatial structure of the site before surgery, yet it is impossible to assess the peripheral anatomical relationship of the trigeminal nerve cistern comprehensively and accurately. This hints that a perfect prediction of the surgical effect of MVD is not possible at present. Thus, typical symptoms of TN are the most critical indicators for MVD surgery.

[Intraoperative decisions and surgical efficacies of trigeminal neuralgia responsible vessels].

OBJECTIVE: To explore the types of primary trigeminal neuralgia (TN) responsible vessels and curative efficacies of microscopic vascular decompression (MVD). METHODS: A total of 162 primary TN patients underwent MVD from August 2004 to the present at our hospital.Their clinical data were collected and analyzed. There were 69 males and 93 females with an age range of 22-88 years. RESULTS: The most common responsible vessels were superior cerebellar artery (n = 65, 40.12%), anteroinferior cerebellar artery (n = 45, 27.78%), multiple vessels (n = 26, 16.05%), posteroinferior cerebellar artery (n = 16, 9.88%), veins (n = 6, 3.70%) and vertebral artery (n = 4, 2.47%). And the pressure points were at the root of trigeminal nerve (n = 139, 85.80%), distal part (n = 16, 9.88%) and root and distal part (n = 7, 4.32%). Postoperatively pain disappeared in all patients (including one case on second surgery). Postoperative follow-ups were conducted for 132 cases.Two cases recurred over 8 years and the recurrence rate was 1.52%. CONCLUSION: MVD is preferred method for primary TN non-responsive to pharmacotherapy. Identification and treatment of responsible vessels remain a key. Venous and distal pressure points should be taken care.

Expression and significance of glucocorticoid receptor alpha in meningiomas.

OBJECTIVE: To explore the expression of the glucocorticoid receptor alpha (GRalpha) and its significance in the occurrence and progress of meningiomas. MATERIALS AND METHODS: By the use of flow cytometry, the proliferative index (PI), S-phase fraction (SPF) and DNA ploidy were detected to evaluate the proliferation of tumor cells in 58 meningioma specimens. The expressions of GRalpha in all meningiomas and seven normal dura samples were studied by means of reverse transcription-polymerase chain reaction to compare the difference in GRalpha between meningiomas and normal dura. The relation between GRalpha and histological grades, PI, SPF and DNA ploidy were also analyzed. RESULTS: The mean PI was 9.32%+/-4.41% while the mean SPF was 2.79%+/-2.43% in 58 meningioma specimens. DNA was diploid in 51 cases and aneuploid in the remaining seven cases, with the aneuploid rate being 12.1%. Nine of 58 meningiomas were GRalpha- negative and the rest were GRalpha-positive with a GRalpha-positive rate of 84.5%. The GRalpha-positive meningiomas included 13 '+', 15 '++', 9 '+++' and 12 '++++'. GRalpha was negative in normal dura samples. The GRalpha-positive rate of meningiomas was significantly greater than that of normal dura. There were no significant differences in PI and SPF among GRalpha-negative, GRalpha-weak positive and GRalpha-strong positive meningiomas. The difference in aneuploid rate between GRalpha-positive and GRalpha-negative meningiomas was also not significant. CONCLUSION: GRalpha is of significance in meningiomas, which are a target tissue for glucocorticoid. However, GRalpha's expression had no obvious effect on the proliferative activity of meningiomas, so it may not be a major control of this process.