Nerve Splitting and Vascular Transposition for Trigeminal Neuralgia Attribute to Nerve Penetrating Trigeminocerebellar Artery: 2-Dimensional Operative Video

The trigeminocerebellar artery (TCA) is an infrequent anatomic anomaly of the branches originating from the basilar artery. It is clinically identifiable by the presence of the ipsilateral superior cerebellar artery and the anterior inferior cerebellar artery, and its course from the basilar artery to the cerebellar hemisphere. Because of its anatomic proximity to the trigeminal nerve root, the TCA often causes trigeminal neuralgia (TGN). Unlike other common arteries, repositioning the TCA is not always feasible when it penetrates the trigeminal nerve root (the intraneural type of TCA). In addition, the rich perforators originating from the TCA may limit its movability. The nerve decompression technique in such a rare condition has not yet been fully assessed. In this video, we present the nerve-splitting method for the intraneural type of TCA, in which sufficient isolation of the sensory root is achieved. The motor root of the trigeminal nerve originates from the brainstem slightly rostral of the root entry zone of the sensory root. Dissecting the motor root from its exit to the porous trigeminus allows mobilization of the root together with penetrating TCA away from the sensory root. The movability of the TCA increases by dissecting its perforators to the nerve root and brain stem. Sufficient separation of the sensory root contributes to ensuring the surgical result of nerve decompression and reducing the risk of recurrence due to adhesion. No complications of motor root retraction, such as masseter weakness and malocclusion, were noted in our experience. All data identifying the patients were anonymized. All procedures performed in this study were in accordance with the ethical standards of our institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. This study also obtained approval from the ethics committee of our institution. Written informed consent was obtained from all individual participants, as well as their first-degree relatives, included in this study.

Dancing larynx syndrome associated with trigeminal neuralgia secondary to multiple sclerosis

A 44-year-old man with multiple sclerosis (MS) presented with focal myoclonus of the mylohyoid and anterior belly of the digastric known as “dancing larynx” [1] which began after gamma knife radiation to the left trigeminal nerve root administered for trigeminal neuralgia (Video 1,). MRI brain showed T2 hyperintensity in the left cerebellopontine angle which expanded following radiation (Figure 1). He received botulinum toxin injections in the mylohyoid muscles with resolution of the movements. The “dancing larynx” was likely from irritation of the trigeminal nerve motor root or pons itself caused by the pontine lesion that enlarged after radiation.

Role of Magnetic Resonance Imaging in Evaluation of Trigeminal Neuralgia with its Anatomical Correlation

Neuropathic Pain is caused by a primary lesion or dysfunction of the peripheral or central nervous system. Trigeminal neuralgia is one such disease which is characterized by episodes of unilateral, lancinating, shock- like pains and are also intermixed with pain free episodes. It has a primary or classic and secondary type. Primary TN is due to neurovascular compression whereas secondary TN is due to any tumor in the brain stem. Trigeminal nerve has a sensory and motor root arising from the pons and travels to the face where it ends as three branches namely ophthalmic, maxillary and mandibular. Magnetic resonance Imaging is a gold in identifying these lesions. However, it is not always prescribed due to lack of insight in using MRI as an evaluating tool. It results in over dosage of medication as the physician prescribes the drug without identifying whether the lesion is primary or secondary. This article give an insight on the various MRI sequences imaged various studies available and also throws light on other sequence which has to be explored in this disease.

Spinal Cord Tumor

Most intradural extramedullary tumors are histologically benign. The three most common intradural extramedullary tumors encountered are meningiomas, schwannomas, and neurofibromas. Excision of intradural meningiomas can be achieved via an en bloc fashion by utilizing a split-thickness durotomy or by ultrasonic aspiration and piecemeal removal. Patients often become symptomatic from spinal cord compression earlier than mass effect upon the brain. Therefore, surgical resection may be undertaken before pial penetration occurs. Neurofibromas commonly arise as a fusiform enlargement of the nerve, making it necessary to sacrifice the root during excision of the tumor. Schwannomas arise from the nerve root of origin, which is usually a nonfunctional dorsal sensory root that can be sacrificed; there is always a corresponding nerve root, which is typically a functional ventral motor root, that needs to be dissected off the tumor.

Herpes Zoster Radiculopathy in a Systemic Lupus Erythematosus Patient – A Case Report

Background:Motor neuropathy is an extremely rare herpes complication, with a mere prevalence of 0.5–5%. The case of segmental zoster paresis of limbs, resulting from motor radiculopathy, is especially limited, with cervical and thoracic segments being the least frequent.Setting:Neurology outpatient clinic. CaseDescription:We report a case of a 16-year-old female who presented sudden-onset right upper extremity weakness, a week after her herpes zoster lesions first appeared. As she was diagnosed with systemic lupus erythematosus (SLE) 4 months prior, she routinely consumed steroids and azathioprine. Initial examinations revealed multiple vesicles along right C5-C6 roots dermatome accompanied by upper right extremity weakness (manual muscle test [MMT] 3) corresponding to the myotome of C5-C6 roots. An electromyography assessment uncovered results relevant to motor root neuritis in C5-C6. Magnetic resonance imaging of the cervical radix with contrast showed no abnormality. Thus, she received acyclovir, gabapentin and physiotherapy.Results:A follow-up visit after 2 weeks revealed an improvement of the weakness along C5-C6 myotome (MMT 4). A month later, all motor functions were restored with hypoesthesia and hypoalgesia sensory sequelae along C5-C6 dermatome.Conclusion:Herpes zoster radiculopathy, though rare, can occur after the onset of characteristic rash. Since cellular-mediated immunity holds crucial roles in varicella zoster virus activation, SLE and immunosuppression therapy is pertinent to this rare motoric complication of herpes. The prognosis is good. Acyclovir, gabapentin and physiotherapy treatments resulted in satisfactory recovery.

Effects of expiratory muscle activation via high-frequency spinal cord stimulation

In persons with spinal cord injury, lower thoracic low-frequency spinal cord stimulation (LF-SCS; 50 Hz, 15 mA) is a useful method to restore an effective cough. Unfortunately, the high-stimulus-amplitude requirements and potential activation of pain fibers significantly limit this application in persons with intact sensation. In this study, the mechanism of the expiratory muscle activation, via high-frequency SCS (HF-SCS; 500 Hz, 1 mA) was evaluated in dogs. In group 1, the effects of electrode placement on airway pressure generation (P) was evaluated. Maximal P occurred at the T9–T10 level with progressive decrements in P at more rostral and caudal levels for both LF-SCS and HF-SCS. In group 2, electromyographic (EMG) latencies of internal intercostal muscle (II) activation were evaluated before and after spinal root section and during direct motor root stimulation. Onset time of II EMG activity during HF-SCS was significantly longer (3.84 ± 1.16 ms) than obtained during direct motor root activation (1.61 ± 0.10 ms). In group 3, P and external oblique (EO) EMG activity, before and after sequential spinal section at the T11–T12 level, were evaluated. Bilateral dorsal column section significantly reduced EO EMG activity below the section and resulted in a substantial fall in P. Subsequent lateral funiculi section completely abolished those activities and resulted in further reductions in P. We conclude that 1) activation of the expiratory muscles via HF-SCS is dependent entirely on synaptic spinal cord pathways, and 2) HF-SCS at the T9 level produces a comparable level of muscle activation with that achieved with LF-SCS but with much lower stimulus amplitudes. NEW & NOTEWORTHY The findings in the present study suggest that lower thoracic high-frequency spinal cord stimulation with low stimulus currents results in sufficient activation of the expiratory muscles via spinal circuitry to produce large positive airway pressures sufficient to generate an effective cough mechanism. This method, therefore, may be applied in patient populations with intact sensation such as stroke and amyotrophic lateral sclerosis to restore an effective cough.