Surgical treatment of trigeminal neuralgia of third division

Extracellular vesicles derived from Porphyromonas gingivalis induce trigeminal nerve-mediated cognitive impairment

INTRODUCTION

Porphyromonas gingivalis (PG)-infected periodontitis is in close connection with the development of Alzheimer's disease (AD). PG-derived extracellular vesicles (pEVs) contain inflammation-inducing virulence factors, including gingipains (GPs) and lipopolysaccharide (LPS).

OBJECTIVES

To understand how PG could cause cognitive decline, we investigated the effects of PG and pEVs on the etiology of periodontitis and cognitive impairment in mice.

METHODS

Cognitive behaviors were measured in the Y-maze and novel object recognition tasks. Biomarkers were measured using ELISA, qPCR, immunofluorescence assay, and pyrosequencing.

RESULTS

pEVs contained neurotoxic GPs and inflammation-inducible fimbria protein and LPS. Gingivally exposed, but not orally gavaged, PG or pEVs caused periodontitis and induced memory impairment-like behaviors. Gingival exposure to PG or pEVs increased TNF-α expression in the periodontal and hippocampus tissues. They also increased hippocampal GP+Iba1+, LPS+Iba1+, and NF-κB+Iba1+ cell numbers. Gingivally exposed PG or pEVs decreased BDNF, claudin-5, and N-methyl-D-aspartate receptor expression and BDNF+NeuN+ cell number. Gingivally exposed fluorescein-5-isothiocyanate-labeled pEVs (F-pEVs) were detected in the trigeminal ganglia and hippocampus. However, right trigeminal neurectomy inhibited the translocation of gingivally injected F-EVs into the right trigeminal ganglia. Gingivally exposed PG or pEVs increased blood LPS and TNF-α levels. Furthermore, they caused colitis and gut dysbiosis.

CONCLUSION

Gingivally infected PG, particularly pEVs, may cause cognitive decline with periodontitis. PG products pEVs and LPS may be translocated into the brain through the trigeminal nerve and periodontal blood pathways, respectively, resulting in the cognitive decline, which may cause colitis and gut dysbiosis. Therefore, pEVs may be a remarkable risk factor for dementia.

Histopathological Evaluation of Inferior Alveolar Neurovascular Bundle in Cases of Trigeminal Neuralgia

BACKGROUND

Trigeminal neuralgia is a painful disease that has been afflicting mankind since time immemorial. The etiology and pathophysiology have been widely studied but poorly understood. There are well-documented researches analyzing ultrastructural changes in trigeminal root specimens obtained following microvascular decompression surgery. However, there are no studies evaluating microscopic changes following peripheral neurectomy.

PURPOSE

The present study examined microscopic changes in inferior alveolar neurovascular bundle in trigeminal neuralgia patients of mandibular division with no underlying cause.

MATERIALS AND METHODS

The biopsy specimens were obtained from peripheral neurectomy of 11 trigeminal neuralgia patients' refractory to anti-neuralgic medications. The autopsy specimens from 10 cadavers were used as control. The specimens were subjected to histopathological examination by hematoxylin and eosin, Masson trichrome and Luxol fast blue stains.

RESULTS

All biopsy specimens reported luminal occlusion of small vessels, medial degeneration and intense mononuclear inflammatory infiltrate. Focal myelin digestion chambers were observed in large and small axons. No pathological alterations of either blood vessel or nerve fibers were reported in autopsy specimens.

CONCLUSION

The demyelination of inferior alveolar nerve due to pathologic vascular changes in peripheral vasculature may have a role in initiation and precipitation of trigeminal neuralgia, and hence, peripheral neurectomy has a significant role in alleviating pain.

Peripheral neurectomy: minimally invasive surgical modality for trigeminal neuralgia in Indian population: a retrospective analysis of 20 cases

OBJECTIVE

To evaluate the efficacy of peripheral neurectomy in 20 cases of trigeminal neuralgia as minimally invasive surgical treatment modality.

MATERIALS AND METHODS

Twenty (12 males and 8 females) patients with trigeminal neuralgia aged between 35 and 68 years (mean 48 years), who had undergone peripheral neurectomy, were retrospectively analyzed for relief of pain, complications, recurrence of pain, and any additional procedure required to treat recurrence, in a follow-up period of 36 months postoperatively.

RESULTS

There was no significant intra-operative and post-operative complications. There was recurrence of pain in two patients (10 %) in 24 and 28 months post-operative follow-up respectively, whereas, rest of the 18 patients were symptom free during 36 months follow-up.

CONCLUSION

Peripheral neurectomy is one of the minimally invasive and expeditious forms of surgical modality for the treatment of trigeminal neuralgia. This treatment option is cost effective and provides long term relief from neuralgic pain.

Peripheral neurectomy: a minimally invasive treatment for trigeminal neuralgia. A retrospective study

AIM

Investigate the efficacy of peripheral neurectomy as a surgical procedure in the treatment of trigeminal neuralgia and to evaluate the results obtained by this procedure and their recurrences in a period of three years followup.

MATERIALS AND METHODS

Thirty patients were retrospectively reviewed who underwent peripheral neurectomy. The factors analyzed were the demographic details of the patients, side of involvement, branch of nerve involved and procedure used postoperative complications, prognosis and any additional procedure used in cases of recurrences.

RESULTS

The mean age of the patient was 57.1 years (range 35-71 years) more were males (M:F = 1.73:1) and the surgical treatment was peripheral neurectomy of the involved branch following failure of carbamazepine therapy. There was no intra operative and postoperative complications noted and follow up over 3 years revealed only two cases (6.66%) of recurrence. Two patients were lost to followup, total number evaluated between 0 and 3 years after treatment was 28 patients.

CONCLUSION

Peripheral neurectomy is one of the oldest, minimal invasive forms of surgery, well tolerated by the patient and can be done under local anesthesia.

Trigeminal neuralgia. Report of 140 cases

140 patients suffering from trigeminal neuralgia are evaluated. 22 patients were treated by symphatholytic and parasympatholytic drugs and the remaining 118 were operated on by peripheral neurectomy and nerve avulsion. In case of involvement of the inferior alveolar nerve, Thoma's, Poppen's and Ginwalla's method were tried. All cases were critically evaluated and followed for a period of 6 months to 5 years. The objective was to assess the different techniques and to find out the most ideal method of management. Our study showed that an injection of atropine was quite promising in the third division involvement while peripheral neurectomy in second division involvement (Ginwalla's technique of nerve avulsion) was found to be more satisfactory than Thoma's or Poppen's method.