Search Results (42)

Background/Objectives: Compression syndromes of the stylohyoid complex (SHC) encompass neural, arterial, and venous presentations extending beyond classic Eagle syndrome. Symptomatic disease is increasingly recognised as a dynamic neurovascular conflict determined not by styloid process (SP) length alone, but by three-dimensional orientation, vessel and nerve proximity, and positional musculoskeletal interactions. This review synthesises that literature and proposes a phenotype-based framework integrating neural, arterial, venous, and mixed presentations. Methods: This is a narrative, pathophysiologically organised review rather than a systematic or scoping review. Landmark anatomical, clinical, and cohort studies were synthesised alongside systematic reviews, meta-analyses, osteological data, and selected case reports illustrating mechanisms not captured at cohort level. Evidence strength was interpreted by study design, distinguishing pooled estimates from retrospective series and proposed mechanisms. Results: The SHC and adjacent C1 transverse process form a narrow corridor containing the internal jugular vein, carotid arteries, and lower cranial nerves. SP elongation is common, but symptomatic compression depends more on orientation, SP-to-C1 distance, vessel proximity, and dynamic positional factors than on length. Three-dimensional CT angiography/venography is the anatomical cornerstone for defining morphology and vessel relationships, whereas catheter venography with manometry remains the haemodynamic reference standard in selected venous cases. Jugular narrowing is frequent in asymptomatic individuals and is not diagnostic without clinical and haemodynamic correlation. Surgical decompression appears favourable in selected patients, whereas primary endovascular stenting, evaluated only in single-centre observational series, carries a substantial complication profile and should generally be reserved for refractory or combined presentations. Conclusions: SHC compression syndromes are best understood as overlapping neural, arterial, venous, and mixed phenotypes within a dynamic neurovascular corridor. A phenotype-based classification and a cautious “styloidectomy-first” strategy for osseous venous compression are proposed as practical frameworks, but require prospective validation. Full article

Background: Isolated hypoglossal nerve palsy is a rare neurological condition with a broad differential diagnosis. Although neoplastic disorders are the most common cause, internal carotid artery dissection (ICAD) is an uncommon but clinically important and potentially reversible vascular etiology that is frequently underrecognized. This systematic review synthesized the available evidence regarding the clinical presentation, imaging findings, pathophysiological mechanisms, treatment, and outcomes of isolated hypoglossal nerve palsy associated with ICAD through a standardized patient-level descriptive analysis. Methods: This systematic review was conducted according to the PRISMA 2020 guidelines and prospectively registered in PROSPERO (CRD420261364863). PubMed, Scopus, Web of Science, and the Cochrane Library were searched from inception to April 2026. Manual reference screening and forward citation tracking were also performed. Studies reporting original, patient-level data on isolated hypoglossal nerve palsy associated with ICAD were eligible. Clinical, imaging, treatment, and outcome data were extracted and synthesized descriptively. In hybrid publications combining original case reporting with a narrative literature review, only eligible, original patient data were included in the quantitative synthesis, whereas the narrative review components were used for citation tracking and contextual comparison. Results: A total of 26 standalone primary publications were included, comprising 23 case reports and 3 case series. Two additional hybrid publications each contributed one eligible patient. One hybrid publication contained an original case-report component, whereas the other reported two original cases and was therefore considered to contain a case-series component, although only one of its patients fulfilled the eligibility criteria. Overall, the 28 publications contributed 32 eligible patients to the patient-level quantitative synthesis. The narrative review components of the two hybrid publications were used solely for citation tracking and contextual comparison. Patients were predominantly male (28/32, 87.5%), with a median age of 47 years. Tongue deviation (28/28, 100%) and tongue weakness (30/30, 100%) were the hallmark clinical features, followed by dysarthria (26/26, 100%) and dysphagia (18/22, 81.8%). All patients presented with isolated hypoglossal nerve palsy at presentation, without Horner syndrome or additional lower cranial nerve involvement. MRI was the most frequently reported imaging modality (29/32, 90.6%), whereas CTA was commonly used to characterize luminal abnormalities. Intramural hematoma (25/26, 96.2%), luminal stenosis (23/26, 88.5%), and external arterial enlargement (22/24, 91.7%) were the most consistent neuroradiological findings. Conservative medical management predominated (31/32, 96.9%). The available evidence was more consistent with a compressive mechanism related to subadventitial arterial wall expansion, although an ischaemic contribution involving the vasa nervorum could not be excluded. A favourable clinical outcome (complete recovery or marked improvement) was observed in 21/30 patients (70.0%). Overall, improvement of any degree, including partial recovery, was documented in 25/30 evaluable patients (83.3%). Outcome data should be interpreted cautiously because they derive predominantly from individual case reports. Conclusions: This systematic review provides an updated standardized synthesis of the available case-level evidence on isolated hypoglossal nerve palsy associated with ICAD. CTA and MRI/MRA provide complementary diagnostic information and may facilitate timely diagnosis when interpreted according to the clinical context. The available evidence identifies recurrent clinico-radiological patterns that may assist clinicians in recognizing this uncommon presentation while highlighting the need for prospective multicentre studies to better inform future diagnostic and therapeutic strategies. Full article

Background: Intracranial accessory nerve schwannomas involving the jugular foramen are rare tumors with heterogeneous clinical presentations. Although lower cranial nerve dysfunction is common, hypoglossal nerve palsy is uncommon and may obscure identification of the nerve of origin. Methods: A narrative review of the literature was conducted to identify reported cases from 1961 to December 2025. Clinical manifestations were categorized as initial and preoperative symptoms, and their temporal evolution was analyzed according to tumor location. Imaging findings, surgical management, and neurological outcomes were reviewed. An illustrative case with hypoglossal nerve palsy was included. Results: A total of 58 cases, including the present case, were identified. According to the Julow classification, 38 tumors were intracisternal and 20 were intrajugular. Intracisternal tumors predominantly caused posterior fossa compression symptoms, whereas intrajugular tumors more frequently showed lower cranial nerve dysfunction. Hypoglossal nerve palsy was observed in seven cases, including three as the initial symptom, and occurred mainly in intrajugular tumors. Imaging commonly demonstrated jugular foramen enlargement and, in selected cases, continuity with enlargement of the extracranial hypoglossal canal. Surgical treatment was associated with improvement or stabilization of hypoglossal nerve function in all reported cases. Conclusions: Accessory nerve schwannomas may occasionally present with hypoglossal nerve palsy, most likely due to secondary compression. Careful assessment of symptom progression and skull base imaging may improve preoperative diagnosis and surgical planning. Full article

Background: Schwannomas of the third cranial nerve are exceedingly rare benign tumors, and standardized management guidelines are lacking. Their close relationship with critical neurovascular structures makes diagnosis and treatment challenging, with a significant risk of postoperative neurological deficits. Methods: A systematic review of the literature was conducted according to the PRISMA guidelines, including case reports and clinical studies on oculomotor nerve schwannomas (ONSs). Demographic data, clinical presentation, tumor location, diagnostic methods, treatment strategies, and functional outcomes were analyzed. In addition, an illustrative case treated with a multimodal approach is presented. Results: Ninety-six cases met the inclusion criteria. The mean age at diagnosis was 34 years, with a slight female predominance. The most common presenting symptoms were diplopia and ptosis. Contrast-enhanced magnetic resonance imaging was the diagnostic modality of choice. Surgical resection was the primary treatment in most cases but was associated with worsening oculomotor nerve function in 43.1% of surgically treated patients. Stereotactic radiotherapy demonstrated favorable tumor control with lower neurological morbidity. In the presented case, subtotal resection followed by stereotactic radiotherapy resulted in sustained tumor stability at the one-year follow-up. Conclusions: Management of oculomotor nerve schwannomas should be individualized. For small or mildly symptomatic lesions, stereotactic radiotherapy appears to be an effective and less invasive option, while surgery should be reserved for large tumors causing a mass effect or progressive neurological deterioration. Full article

HTLV-1 and HTLV-2 infections are associated with various neurological manifestations, particularly HTLV-1-associated myelopathy (HAM). This descriptive, cross-sectional observational study aimed to investigate and analyze the neurological manifestations in patients treated at the Service for the Care of People Living with HTLV (Serviço de Atendimento à Pessoa Vivendo com HTLV-SAPEVH) at the Federal University of Pará. A cohort of 957 individuals underwent screening for HTLV-1/2 infection using enzyme-linked immunosorbent assay (ELISA), with seropositive samples subsequently confirmed via Western blotting or quantitative polymerase chain reaction (qPCR). HTLV-1/2 infection was confirmed in 69 individuals. Of these, fifteen individuals—diagnosed with HTLV-1 (n = 11) or HTLV-2 (n = 4) infection—who presented with neurological complaints at the first nursing consultation, were referred to a neurologist for clinical evaluation of neurological signs and symptoms. Most of the patients were female (13), ranging from 33 to 80 years of age. Neurological symptoms were present in 86.7%, and included spasticity, paraparesis, chronic pain, both motor and sensory deficits, as well as urinary disorders, predominantly affecting the thoracic spinal cord and lower limbs. Urinary symptoms were observed in 77% of symptomatic patients, often preceding other neurological signs that suggest a role as “sentinel symptoms” in the clinical screening of HTLV carriers. The results demonstrated the presence of neurological impairment in patients infected with both HTLV-1 and HTLV-2, with motor symptoms ranging from moderate to advanced. In addition, cases of cranial nerve and upper limb involvement were reported, a finding that is rarely described in the literature. The study highlights the importance of neurological assessment as early as possible in patients infected with either HTLV-1 or HTLV-2 and suggests that sphincter dysfunctions can serve as early clinical markers of future neurological impairment. Full article

A 79-year-old former marathoner, with memory impairment since age 78, developed increasing stumbling and progressively worsening waddling gait. Three months after gait disturbance onset, she noted mild dysphagia. With declining walking distance and endurance, she presented to our hospital six months after onset, exhibiting frontal signs, Parkinsonism with marked trunk rigidity, and hyperreflexia of the jaw and limbs. L-dopa challenge tests showed no improvement. At seven months post-onset, she had difficulty rising. By nine months, she relied on a walker, and speech disturbance appeared. At 10–11 months, both dysarthria and dysphagia rapidly worsened, she became bed-ridden, and upper limb weakness developed (though she could still use chopsticks). Neurological examination at one year revealed severe dysarthria/dysphagia, four extremity fasciculations and muscle weakness (grade 2 in upper limbs, grade 1 in lower limbs), trunk-dominant rigidity, and hyperreflexia in the jaw and limbs. Brain MRI, specifically susceptibility-weighted imaging, revealed motor band signs. Cerebrospinal fluid study revealed albuminocytological dissociation. Needle electromyography revealed acute denervation and chronic reinnervation in the cranial nerve, cervical, and lumbar areas, which was suggestive of motor neuron disease (MND). Serum anti-GQ1b antibodies were detected. Immunotherapy was followed by mild improvement, which might suggest a reversible component, although definitive pathological overlap remains unconfirmed. This case highlights a diagnostic challenge where an acute immune-mediated neuropathy could potentially be superimposed on a chronic neurodegenerative process. Anti-GQ1b antibodies should be interpreted with caution, as they may reflect either a true clinicopathological overlap with Guillain-Barré syndrome or a secondary phenomenon (epiphenomenon) related to the primary neurodegenerative process. Full article

Primary parapharyngeal space (PPS) tumors are rare neoplasms comprising 0.5% of head and neck tumors. Their complex anatomical location and proximity to critical neurovascular structures pose significant surgical challenges. While transcervical and transcervical-combined approaches represent the primary surgical techniques, no comprehensive systematic comparison exists. This systematic review compared surgical success, complications, functional outcomes, and recurrence rates between these approaches. Following PROSPERO registration (CRD420251037201), we searched PubMed, Cochrane, Web of Science, Google Scholar, and ScienceDirect without date restrictions. Independent dual screening identified retrospective cohort studies and case series comparing both approaches. Data extraction and risk of bias assessment employed standardized tools, with synthesis conducted per PRISMA 2020 guidelines using narrative analysis. Ten studies encompassing 505 patients with 508 tumors met inclusion criteria. Both approaches achieved excellent complete resection rates (95–100%). Transcervical approaches demonstrated lower overall complication rates (4.8–52.6%) versus transcervical-combined approaches (7.7–100%), though rates varied substantially by tumor type, and differences likely reflect case selection rather than approach-specific effects. Cranial nerve injuries (VII, X, XII) constituted predominant complications. Infratemporal fossa approaches showed the highest morbidity. Recurrence rates ranged from 0–30.3% without consistent patterns favoring either approach. Transcervical-combined approaches were essential for superior compartment extension and for skull base involvement. Both transcervical and transcervical-combined approaches achieve excellent tumor resection with acceptable morbidity when appropriately selected. For most benign PPS tumors, a transcervical approach may be preferred. Combined approaches may be considered in specific anatomic scenarios that require enhanced exposure, particularly when the superior compartment and skull base are involved, although the decision is always highly individual. Full article

Background and Clinical Significance: Hypoglossal nerve palsy is an uncommon neurological complication of infectious mononucleosis and is only rarely reported. Putative mechanisms include virus-triggered neuritis (Epstein–Barr virus (EBV) or Cytomegalovirus (CMV)) and/or mechanical compression related to cervical lymphadenopathy. Case Presentation: We report two children with infectious mononucleosis and transient unilateral hypoglossal nerve palsy. Case 1 was a 15-year-old boy with 7 days of fever and typical mononucleosis features who developed leftward tongue deviation accompanied by sialorrhea, dysarthria, and dysphagia. Laboratory testing showed marked hepatocellular injury and EBV-specific IgM positivity. Case 2 was a 9-year-old girl with a 24 h history of bilateral lateral cervical lymphadenopathy with overlying inflammatory signs; examination revealed rightward tongue deviation with similar associated symptoms. CMV-specific IgM antibodies were detected on serological testing. Both patients received systemic corticosteroids and empiric intravenous antibiotics, with supportive care. Hypoglossal nerve function fully recovered within 2–4 weeks of treatment initiation. Conclusions: These cases underscore that isolated hypoglossal nerve palsy may complicate EBV- or CMV-associated mononucleosis in children. Although the prognosis is generally favorable, the presentation warrants careful evaluation to exclude alternative causes of lower cranial neuropathies and close follow-up until complete neurological resolution. Full article

Objectives: To characterize the learning curve of endoscopic transsphenoidal pituitary adenoma surgery performed by a single neurosurgeon, assess how operative time, resection rates, and clinical outcomes evolved with experience, and identify tumor-related factors influencing surgical performance. Methods: This retrospective study included 123 consecutive endoscopic transsphenoidal pituitary adenoma resections performed between 2018 and 2025. Cases were divided into quartiles according to chronological order. Clinical, radiological, endocrinological, and operative variables were analyzed. Gross total resection (GTR), biochemical remission, postoperative complications, and visual and cranial nerve outcomes were compared between quartiles. A segmented linear regression model was applied to identify changepoints in the operative-time learning curve. Statistical significance was set at p < 0.05. Results: The mean operative time decreased by 31.8%, from 160.8 min in Quartile 1 to 109.7 min in Quartile 4. Segmented regression revealed two changepoints at cases 47 and 85, defining three learning phases: a steep improvement phase, a consolidation phase, and a plateau. GTR was achieved in 51.2% of patients and did not significantly differ across quartiles. For Knosp 0–2 tumors, GTR was 76.1% overall; for Knosp 3–4 tumors, 30%. Tumor diameter, Knosp grade, and sphenoid sinus invasion were strongly associated with lower GTR rates (all p < 0.05). Biochemical remission was achieved in 74.2% of patients with functional adenomas. New or worsened postoperative pituitary insufficiency significantly decreased across quartiles (p < 0.001). Rates of postoperative diabetes insipidus (30.8%) and CSF leak (6.5%) were comparable with published literature and showed no consistent temporal trend. Conclusions: A clear learning curve exists in endoscopic pituitary surgery, with operative proficiency achieved after approximately 50 cases and an experienced plateau after ~90 cases. Surgical experience significantly reduced operative time and postoperative pituitary insufficiency but did not influence GTR rates, likely due to a high and increasing proportion of large tumors with cavernous sinus invasion. Tumor size, Knosp grade, and sphenoid sinus invasion were identified as major determinants of surgical complexity and should be accounted for when evaluating learning curves and surgical outcomes. Full article

Background/Objectives: Tumors of the cerebellopontine angle (CPA) encompass a limited range of histologies, predominantly vestibular schwannomas (VSs), meningiomas, and paragangliomas (PGLs). Their growth region threatens the cranial nerves (V–XII), brainstem, and cerebellum, possibly causing functional deficits. This review aims to synthesize clinical features and multidisciplinary treatment strategies for CPA tumors with brainstem involvement, emphasizing functional preservation alongside tumor control. Methods: A systematic PubMed search identified studies on VSs, CPA meningiomas, and intradural PGLs. Eligibility criteria included studies reporting tumor management and cranial nerve outcomes. Data extraction focused on tumor size, neurological presentation, surgical approach, adjunctive therapies, and postoperative cranial nerve function. Multidisciplinary involvement and rehabilitation strategies were noted. Results: Twenty studies (3311 patients) analyzed large VSs, showing facial nerve dysfunction in 8–53%, trigeminal neuropathy in 20–77%, and cerebellar signs in up to 79%. Microsurgery (MS) achieved variable gross total resection, while stereotactic radiosurgery (SRS) preserved facial nerve function but carried trigeminal and hydrocephalus risks. CPA meningiomas demonstrated cranial nerve displacement patterns critical for surgical planning, with transient deficits common and recovery linked to baseline function. In 388 intradural PGL cases, staged surgery combined with preoperative embolization was standard; functional preservation of lower cranial nerves was often limited. Across all histologies, multidisciplinary management and targeted rehabilitation were essential. Conclusions: Optimal CPA tumor management balances tumor control with functional preservation. VSs benefit from individualized MS or SRS based on size and mass effect. Meningioma surgery prioritizes cranial nerve preservation over radical resection. Intradural PGLs require staged vascular-conscious approaches. Multidisciplinary care and structured rehabilitation are pivotal to improving outcomes and quality of life. Full article

The stylohyoid complex (SHC), comprising the styloid process (SP), stylohyoid ligament, and lesser horn of the hyoid bone, arises from Reichert’s cartilage and plays a central role in head and neck organization. Although anatomically small, it occupies a strategic position in the parapharyngeal space, linking neural, vascular, and visceral compartments. This review integrates embryological, comparative, anatomical, and clinical perspectives to provide an updated synthesis of SHC morphology and significance. Developmental studies highlight the early segmentation of Reichert’s cartilage, its transient relationships with the otic capsule, facial canal, and carotid arteries, and its role in shaping muscular and fascial compartments. Comparative anatomy demonstrates the evolutionary transition from a continuous ossicular chain to a vestigial human structure, reflecting a trade-off between rigidity and vocal tract flexibility. In humans, the SHC exhibits marked variability in length, angulation, segmentation, and ligamentous ossification, which directly influence its spatial relationships with the internal and external carotid arteries, the internal jugular vein, and the lower cranial nerves. These variations underpin the clinical spectrum of Eagle’s syndrome and vascular complications, including carotid artery dissection and jugular compression syndromes. Recognition of these embryological origins, evolutionary trajectories, and anatomical variants is essential for accurate diagnosis, imaging interpretation, and surgical planning. As both an embryological remnant and a clinical landmark, the SHC bridges fundamental anatomy with practical implications for imaging, diagnosis, and surgery. Full article

Introduction: Tympanojugular paragangliomas (TJ-PGs) showing intradural growth into the cerebellopontine angle (Fisch classification Di) represent a surgical challenge, with their proper surgical management still under debate. Methods: This is an international multicenter retrospective review of patients with Di TJ-PGs who underwent surgery in three high-volume skull base surgery centers. We aimed to establish practice patterns for treating Di TJ-PGs, namely the surgical approach, total versus partial resection, and whether a staged procedure was needed. We also examined the status of the facial and lower cranial nerves (LCNs), postoperative complications, and residue management after partial resection. Results: Thirty-two patients were included in this study with an average follow-up of 66 months. Preoperative angiography with selective embolization was performed in all patients, and a type A infratemporal fossa approach was the most common surgical technique. Total resection was achieved in 16 cases. A single-stage procedure was performed in 26 patients and a staged procedure in 6. CSF leakage in the neck was the main reported complication. Most patients had an HB I-II-grade facial nerve at the last follow-up, and three patients experienced worsened lower cranial neuropathies. In 16 patients residual disease was present after surgery and was managed with either radiotherapy or observation. Conclusions: Di TJ-PGs pose a complex treatment challenge for which clear-cut management recommendations have not been established. Surgical resection, when indicated, may be total, the preferred option in young healthy candidates, or partial, mainly employed in elderly or high-risk patients, always considering the tumor’s relationship to critical structures. When residual tumor is present, both radiological surveillance and adjuvant radiotherapy can be effective strategies. Full article

The varicella-zoster virus is a human herpesvirus that causes varicella as the primary infection and HZ as the reactivation of a latent infection. Ten to twenty percent of cases of herpes zoster ophthalmicus (HZO) involve the ophthalmic branch of the fifth cranial nerve. Any area of the eye may be affected by the condition. HZ has a lifetime risk of more than 30%. Complications from herpes zoster can significantly lower quality of life. The goal of HZ vaccinations is to stop HZ activation and PHN formation. Despite the uncommon possibility of side effects such as eye problems, the majority of vaccines on the market now are safe. The purpose of this review is to discuss VZV infection and analyze and summarize the ocular complications following VZV vaccination. Full article

Background/Objectives: Schwannoma is a rare tumor, typical in young adults, originating from the myelin sheath that surrounds Schwann cells. It can occur in any part of the Peripheral Nervous System (PNS). It develops in the head and neck region in 25–48% of cases, and the eighth pair of cranial nerves (vestibulocochlear nerves) are the most hit (vestibular schwannoma). Oral cavity involvement is exceedingly rare, accounting for about 1–2% of all cases. The most affected oral site is the tongue, especially its anterior third, while localization on the lip is one of the least common sites for the development of this lesion. Case Presentation: A lower lip schwannoma on a 17-year-old boy, present for about 7 years, was documented. Material and Methods: PubMed and Google Scholar were used as research engines; English scientific works published in the last 20 years (2005–2024) regarding oral cavity involvement, using the keywords “Schwannoma”, “Oral Schwannoma”, “Pediatric Oral Schwannoma”, and “Schwannoma of the lip”, were considered. Results: In total, 805 and 16,890 items were found on PubMed and Google Scholar search engines, respectively. After title, abstract, full text evaluation, and elimination of duplicates, 26 articles were included in the review process. Discussion: Clinically, oral schwannoma presents as an asymptomatic hard–elastic fluctuating mass, often misdiagnosed on the lip as a traumatic or inflammatory lesion (e.g., mucocele). Biopsy is mandatory, and histological examination reveals positivity to the neuronal marker S-100. Conclusions: Complete excision also prevents recurrence. Malignant transformation is extremely rare. Full article

(1) Introduction: The main way of spreading the herpes simplex virus 1 (HSV-1) is through direct contact, as the virus enters the host via mucous membranes. Ocular infection can occur as a primary infection or as a recurrent one. The movement of HSV-1 along the ophthalmic branch of the fifth cranial nerve from its latency phase in the trigeminal ganglion and its activation represent a process influenced by various symbiotic factors, such as environmental conditions and the host’s genetic characteristics. The aim of this study was to assess the frequency of IL28 (rs12980275) and (rs8099917) in recurrent ocular HSV infections. (2) Materials and methods: The study included 60 patients aged over 18, of both sexes, all of whom had a history of herpes simplex labialis (HSL). Patients were tested for HSV-1-specific IgG antibodies, and seropositive individuals were genotyped for single nucleotide polymorphisms (SNPs) rs12980275 and rs8099917. A total of 57 seropositive patients were included in the study. (3) Results: A statistically significant association was found between recurrent HSV keratitis (HSK) and heterozygous GT rs8099917 and homozygous TT rs8099917, as well as heterozygous AG rs12980275 and homozygous AA rs12980275 (p < 0.01). Interestingly, patients with homozygous GG polymorphism for both genotypes GG rs8099917 and GG rs12980275 did not develop recurrent HSV keratitis. (4) Conclusion: The most frequent SNP variations in patients with recurrent HSV disease were heterozygous AG rs12980275 (61.40%) and heterozygous GT rs8099917 (52.63%). Patients with recurrent HSV keratitis lacked the homozygous GG polymorphism in both GG rs8099917 and GG rs12980275 genotypes, suggesting that HSV-seropositive individuals expressing these genotypes may have lower predisposition to develop recurrent stromal HSV keratitis. Full article