Synchronous presentation of trigeminal, glossopharyngeal and geniculate neuralgias in a single patient

A pain in the ear: Two case reports of nervus intermedius neuralgia and narrative review

OBJECTIVE

Present two cases of nervus intermedius neuralgia (NIN) in which patients described unilateral deep ear pain as their primary complaint and present a summary of NIN cases reported in the literature.

BACKGROUND

The nervus intermedius is a tiny branch of the facial nerve that, with neuralgia, can present as a deep ear pain (NIN). The International Classification of Headache Disorders, 3rd edition, (ICHD-3) criteria for an NIN diagnosis include a unilateral deep ear pain with possible radiation that occurs in paroxysms with sharp pain and a tactile trigger.

METHODS

A PubMed search was conducted for NIN and geniculate neuralgia. Two patients recently diagnosed with NIN at a single clinic were selected for case reports to highlight the variability of symptom presentation.

RESULTS

The two cases reported here and the 127 cases reported in the literature show a wider range of presentations than included in the ICHD-3 criteria, including variable pain radiation sometimes diagnosed as concurrent trigeminal, glossopharyngeal, or occipital neuralgia. Pain was reported as constant or paroxysmal, as well as dull, sharp, or neuralgiform with inconsistent presence of triggers. While ICHD-3 does mention reported taste change, lacrimation, and salivation, the literature reports a much wider range of potential features associated with NIN. Optimal medical treatment is unclear given the predominance of surgical reporting of positive response to microvascular decompression, nerve sectioning, or other procedures. The two cases described here were successfully managed medically.

CONCLUSION

NIN can present as described in the ICHD-3, but a more variable presentation may be possible. More studies are needed to clarify presentation, optimal medical treatment, and surgical indications for patients with NIN, especially when patients have no clear neurovascular conflict on neuroimaging.

Reoperation after failed microvascular decompression for glossopharyngeal neuralgia

BACKGROUND

Microvascular decompression (MVD) is known as a safe and effective procedure to treat glossopharyngeal neuralgia (GN). However, some patients experienced poor pain relief after MVD, for which the mechanism is not clear yet. Reviewing the intraoperative findings and postoperative effect of reoperation for patients who failed the first MVD, is helpful to figure out why the first MVD for GN failed.

METHODS

There were eight patients with GN who failed first MVD. The possibilities for secondary GN were eliminated by physical and radiological examination. The reoperation through the previous incision was conducted, and appropriately, treatment was provided according to the intraoperative findings. The video data and prognosis of the reoperation were retrospectively reviewed. The reasons for the invalid first MVD were analyzed.

RESULTS

To the end of follow-up, there were 7 patients of pain-free, and one patient with occasional mild pain attacks (VAS 2). There was one patient who experienced transient hoarseness in 3 months after the reoperation. We summarized the causes for failed first MVD which were omission of the offending vessel in 3 cases, inadequate decompression of the nerve root in 2 cases, and excessive decompression materials which caused iatrogenic nerve root compression in 3 cases.

CONCLUSIONS

For patients with recurrent or failed after MVD, a thorough examination should be carried out to eliminate the possibility of secondary GN. Reoperation through the previous incision is safe and effective. The bone window should be close enough to the sigmoid sinus to aid the exposure of the nerve root. The nerve transection could be adopted if no offending vessels were found. And a multi-site decompression could be used when the vertebral artery is the offending vessel.

Adaptive Bayesian label fusion using kernel-based similarity metrics in hippocampus segmentation

The effectiveness of brain magnetic resonance imaging (MRI) as a useful evaluation tool strongly depends on the performed segmentation of associated tissues or anatomical structures. We introduce an enhanced brain segmentation approach of Bayesian label fusion that includes the construction of adaptive target-specific probabilistic priors using atlases ranked by kernel-based similarity metrics to deal with the anatomical variability of collected MRI data. In particular, the developed segmentation approach appraises patch-based voxel representation to enhance the voxel embedding in spaces with increased tissue discrimination, as well as the construction of a neighborhood-dependent model that addresses the label assignment of each region with a different patch complexity. To measure the similarity between the target and training atlases, we propose a tensor-based kernel metric that also includes the training labeling set. We evaluate the proposed approach, adaptive Bayesian label fusion using kernel-based similarity metrics, in the specific case of hippocampus segmentation of five benchmark MRI collections, including ADNI dataset, resulting in an increased performance (assessed through the Dice index) as compared to other recent works.