BACKGROUND: Trigeminal schwannomas (TSs) are intracranial tumors that can cause significant brainstem compression. TS resection can be challenging because of the risk of new neurologic and cranial nerve deficits, especially with large (≥ 3 cm) or giant (≥ 4 cm) TSs. As prior surgical series include TSs of all sizes, we herein present our clinical experience treating large and giant TSs via microsurgical resection.
METHODS: This was a retrospective, single-surgeon case series of adult patients with large or giant TSs treated with microsurgery in 2012-2023.
RESULTS: Seven patients underwent microsurgical resection for TSs (1 large, 6 giant; 4 males; mean age 39 ± 14 years). Tumors were classified as type M (middle fossa in the interdural space; 1 case, 14%), type ME (middle fossa with extracranial extension; 3 cases, 43%), type MP (middle and posterior fossae; 2 cases, 29%), or type MPE (middle/posterior fossae and extracranial space; 1 case, 14%). Six patients were treated with a frontotemporal approach (combined with transmastoid craniotomy in the same sitting in one patient and a delayed transmaxillary approach in another), and one patient was treated using an orbitofrontotemporal approach. Gross total resection was achieved in 5 cases (2 near-total resections). Five patients had preoperative facial numbness, and 6 had immediate postoperative facial numbness, including two with worsened or new symptoms. Two patients (28%) demonstrated new non-trigeminal cranial nerve deficits over mean follow-up of 22 months. Overall, 80% of patients with preoperative facial numbness and 83% with facial numbness at any point experienced improvement or resolution during their postoperative course. All patients with preoperative or new postoperative non-trigeminal tumor-related cranial nerve deficits (4/4) experienced improvement or resolution on follow-up. One patient experienced tumor recurrence that has been managed conservatively.
CONCLUSIONS: Microsurgical resection of large or giant TSs can be performed with low morbidity and excellent long-term cranial nerve function.

BACKGROUND: Neurosarcoidosis is rare, and among its manifestations, nerve root involvement has been reported in only a few cases. Therefore, magnetic resonance imaging (MRI) findings of neurosarcoidosis, particularly those involving nerve roots, are scarce in the literature.
METHODS: We presented the case of neurosarcoidosis involving cervical nerve roots and cranial nerves, alongside a systematic literature review.
RESULTS: A 28-year-old female suddenly developed right facial numbness as well as left upper extremity and left hand pain. Initial brain and spine MRI showed a bulging mass of T2 iso-to-high signal intensity in the left Meckel\'s cave/trigeminal nerve, as well as diffuse enlargement of the right C6 and C7 nerve roots. Follow-up MRI at 2 months revealed a reduction in the size of the initial lesion and the appearance of new similar lesions on the contralateral side (right Meckel\'s cave, left C3-C8 nerve roots). In particular, the lesions involving the nerve roots demonstrated central enlargement along the nerve roots, without involvement of the adjacent spinal cord. All these lesions exhibited enhancement, leading to the differentiation between sarcoidosis and lymphoma. Sarcoidosis was subsequently confirmed through biopsy of a hilar lymph node.
CONCLUSIONS: This report presents a distinctive MRI feature of neurosarcoidosis involving spinal nerve roots, representing the first of its kind, and describes the evolution of MRI findings throughout the clinical course.

BACKGROUND: Cavernous malformations (CMs) are clusters of thin-walled sinusoidal vessels without well-defined walls. Though they can occur anywhere in the neuroaxis, cranial nerve (CN) CMs are rare.
METHODS: We report a 47-year-old male with gradual CN III palsy. Initial imaging showed no significant findings, but a follow-up MRI revealed a growing lesion along CN III. Intraoperative findings confirmed a CN III CM. Diagnosing and treating CN III CM are complex. Radiological findings lack specificity, requiring consideration of various diagnoses for patients with isolated CN III palsy and abnormal radiological findings.
CONCLUSIONS: Surgery is the gold standard, aiming for complete lesion removal while minimizing neurological complications.

An 11 years old male Labrador cross presented with unilateral vestibular signs, ipsilateral facial paresis, moderate obtundation, ptyalism, and paraparesis. MRI of the brain revealed diffuse, multifocal T2/FLAIR hyperintense changes throughout various regions of the brain including the medulla, midbrain, pons, thalamus and right cerebral hemisphere with mild multifocal contrast enhancement. The patient progressed to trismus with generalized increased extensor tone and risus sardonicus. A diagnosis of generalized tetanus was made and the patient was started on antibiotics, skeletal muscle relaxants and tetanus antitoxin and made a full recovery. To the best of the authors\' knowledge, this is the first reported case of canine tetanus in which the presenting signs involved cranial nerve dysfunction as well as the first report describing MRI changes in canine tetanus within the central nervous system.

Ramsay Hunt syndrome is a clinical manifestation of the reactivation of latent varicella zoster virus in the geniculate ganglion after acute infection. It is commonly associated with an acute peripheral facial nerve paralysis, auricular vesicular eruption and acute sensorineural hearing loss. However, in some rare cases the involvement of other cranial nerves, especially the glossopharyngeal and vagal is described. We present a 56-year-old male patient who was diagnosed with acute pharyngitis. Two days later, the patient developed dysarthria, hoarseness, and left side facial weakness. Considering a patient\'s history of cardiovascular events, the acute stroke was suspected. Magnetic resonance imaging ruled out an acute cerebrovascular accident. The patient\'s otalgia aggravated and he reported hearing loss. Clinical examination revealed facial paralysis affecting the left side of the face, erythematous rash on the left auricle, multiple vesicles present on patient\'s left tympanic membrane, ulcerous lesion on the left side of the soft palate and ipsilateral velopharyngeal palsy. Indirect laryngoscopy revealed ulcerous lesions in the left side of the epiglottis and left vocal cord paralysis. The patient was diagnosed with Ramsay Hunt syndrome with cranial polyneuropathy. Oral acyclovir and oral prednisolone were administered. Seven months after discharge, facial paralysis improved to lower grade and flexible laryngoscopy showed that the left vocal cord had resumed normal movement. Ramsay Hunt syndrome can be accompanied by involvement of other cranial nerves. Previous history of hypertensive crises and myocardial infarction may influence a diagnosis of Ramsay Hunt syndrome, especially when it has atypical presentation. However, this diagnosis should be considered in patients with unilateral multiple cranial nerve palsies.

UNASSIGNED: Isolated inferior rectus muscle palsy is a rare entity and even more rarely induced by an anatomical conflict. We report here a clinical case of third cranial nerve (CN III) compression in its cisternal segment by an idiopathic uncal protrusion in a patient presenting an isolated inferior rectus muscle palsy.
UNASSIGNED: We report a case of an anatomical conflict between the uncus and the CN III in the form of a protrusion and highly asymmetrical proximity of the uncus and asymmetrically thinned nerve diameter deviated from its straight cisternal trajectory on the ipsilateral side were supported by an altered diffusion tractography along the concerned CN III. Clinical description, review of the literature, and image analysis were done including CN III fiber reconstruction using a fused image from diffusion tensor imaging images, constructive interference in steady state, and T2-fluid-attenuated inversion recovery images on a dedicated software (BrainLAB AG).
UNASSIGNED: This case illustrates the importance of anatomical-clinical correlation in cases of CN deficits and supports the use of new neuroradiologically based interrogation methods such as CN diffusion tractography to support anatomical CN conflicts.

Neurolymphomatosis is rarely encountered in high-grade lymphomas. In this case series, we retrospectively analyzed six neurolymphomatosis cases to look for possible risk factors, common and uncommon presentations, and the lessons learned. Neuropathic pain was the most common symptom with mono or polyradiculopathy in this series. However, all lymphomatous infiltrated nerves diagnosed on fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) were not symptomatic. The lumbar, brachial plexus, and trigeminal nerve were the most common sites and were depicted well on FDG PET/CT. Magnetic resonance imaging (MRI) of the brain better delineates cranial nerves and meningeal involvement. Cerebrospinal fluid flow cytometry was normal until meninges were involved. FDG PET/CT incrementally evaluated extra-neural disease sites, thus helping in deciding biopsy sites and further management. We concluded that a whole-body FDG PET/CT including limbs with MRI brain was the appropriate investigation for evaluating suspected neurolymphomatosis in advanced-stage diffuse large B-cell lymphoma.

The anti-GQ1b IgG antibody is often accompanied by other anti-ganglioside antibodies, which induces various neurological symptoms. We herein report a patient with anti-ganglioside antibodies, including anti-GQ1b IgG and anti-GT1a IgG antibodies, showing bilateral ophthalmoplegia, facial nerve palsies, dysarthria, dysphagia, dysesthesia in both hands, and enhancement of the bilateral oculomotor, abducens, and facial nerves on gadolinium (Gd)-enhanced T1-weighted brain magnetic resonance imaging (MRI). He was first treated with intravenous immunoglobulin, which improved ophthalmoplegia, bulbar palsies, and dysesthesia of hands, but the facial nerve palsies worsened, and Gd enhancement of the brain nerves persisted. High-dose methylprednisolone therapy subsequently improved the facial nerve palsies and Gd enhancement of the cranial nerves. This is the first case with anti-ganglioside antibodies presenting with multiple cranial nerve palsies that was followed to track the changes in the Gd enhancement of cranial nerves on MRI.

(1) Background: This study aimed to evaluate the efficacy and treatment-related toxicity of proton radiotherapy (PRT) for vestibular schwannoma (VS) in patients with neurofibromatosis type 2-related schwannomatosis (NF2). (2) Methods: Consecutive NF2 patients treated with PRT for VS between 2004 and 2016 were retrospectively evaluated, focusing on tumor volume, facial and trigeminal nerve function, hearing, tinnitus, vestibular symptoms, and the need for salvage therapy after PRT. (3) Results: Eight patients were included (median age 36 years, 50% female). Median follow-up was 71 months. Five (63%) patients received fractionated PRT and three (38%) received PRT radiosurgery for VS. Six patients (75%) received prior VS surgery; three also received bevacizumab. Six patients (75%) did not require salvage therapy after PRT. Two patients (25%) with residual hearing lost it after PRT, and six had already lost ipsilateral hearing prior to PRT. Tumor and treatment-related morbidity could be evaluated in six patients. Following PRT, conditions that occurred or worsened were: facial paresis in five (83%), trigeminal hypoesthesia in two (33%), tinnitus in two (33%), and vestibular symptoms in four patients (67%). (4) Conclusion: After PRT for VS, the majority of the NF2 patients in the cohort did not require additional therapy. Tumor and/or treatment-related cranial nerve deficits were common. This is at least partly explained by the use of PRT as a salvage treatment after surgery or bevacizumab, in the majority of cases. There remains the further opportunity to elucidate the efficacy and toxicity of proton radiotherapy as a primary treatment.

This study reported a case of a Rhino-Orbital-Cerebral Mycosis (ROCM) patient with multiple groups of cranial nerve damage as the primary clinical manifestation, confirmed by histopathology and cerebrospinal fluid metagenomic next-generation sequencing (mNGS) technology. Relying on the MRI3D-SPACE technology, we observed the location and extent of the cranial nerve damage in the patient. The results suggested that fungal meningoencephalitis caused by mucor may enter the skull retrograde along the cranial nerve perineurium. The patient was admitted to the hospital with a preliminary diagnosis of mucormycosis infection after 1.5 days of mouth deviation. We treated the patient immediately with intravenous amphotericin B liposomes. After 21 days of hospitalization, the clinical symptoms of the patient did not improve significantly. The patient was discharged due to financial difficulties and antifungal treatment at home, and his disease had stabilized at the 6-month follow-up.