OBJECTIVE: Cranial nerve (CN) involvement is not a common feature of typical chronic inflammatory demyelinating polyneuropathy (CIDP). Patients with acute presentation of CN palsy in CIDP may be misdiagnosed and treated as other pathologies.
METHODS: We report a patient with multiple cranial neuropathies at the onset of CIDP in detail. In addition, we reviewed a large cohort of patients with CN involvement in CIDP and summarized their characteristics and clinical findings.
RESULTS: We presented a 28-year-old woman who presented with progressive weakness and involvement of CN III, VII, X, XII in the subacute phase who was diagnosed as CIDP and was treated accordingly. A scoping review of the literature resulted in a total of 59 patients with available patient-level data [61.2% men, median age of 32 (Q1-Q3; 20-51.5) years]. CN impairment was present in the acute phase of the polyneuropathy in 10 out of 43 patients (23.3%), while it took a median of 7.7 [Q1-Q3; 3-13] years for other patients to present CN palsy. Sensitivity analysis did not reveal any difference among patients with acute-phase presentation of CN symptoms (N = 11) compared with those with delayed CN palsy (N = 33) in terms of demographics, patterns of CN involvement, associated diminished sensorimotor findings, or relapse. However, patients with acute presentation of CN palsy underwent plasmapheresis approximately 4 times more than those with delayed CN presentations (45.5% vs. 12.1%, P = 0.02).
CONCLUSIONS: In this case presentation and review study, we observed that in one-fourth of patients with CIDP and CN neuropathy, CN involvement occurred in the acute phase. This finding indicates the necessity of considering CIDP among differential diagnoses of patients with CN involvement and polyneuropathies.

BACKGROUND: Jugular paragangliomas are highly vascularized tumors that can grow in challenging neurovascular compartments and are particularly challenging to resect. There is still no consensus whether preoperative embolization should be employed to minimize intraoperative morbidity.
METHODS: A systematic review and meta-analysis was conducted by searching PubMed, Web of Science, and Embase databases for key terms including \"embolization,\" \"jugular paragangliomas,\" and \"surgery.\"
RESULTS: This review included 25 studies with 706 patients and 475 (67%) preoperative embolizations. Polyvinyl alcohol particles were the most common embolic agent (97.8% of all patients who underwent embolization). Complication rate of embolization was 1% (95% confidence interval [CI]: 0%, 2%). Preoperative embolization was significantly associated with less intraoperative estimated blood loss (mean difference of -7.92 dL [95% CI: -9.31 dL, -6.53 dL]), shorter operating room times (mean difference of -55.24 minutes [95% CI: -77.10 minutes, -33.39 minutes]), and less overall tumor recurrence (odds ratio = 0.23 [95% CI: 0.06, 0.91]) compared with resective surgery alone. Preoperative embolization had no impact on the development of postoperative new cranial nerve deficits not associated with embolization (odds ratio = 1.17 [95% CI: 0.47, 2.91]) and achievement of gross total resection (odds ratio = 1.92 [95% CI: 0.67, 5.53]).
CONCLUSIONS: Preoperative embolization may provide surgical efficiency with faster surgical times and less bleeding and safety with diminished overall recurrence via safe embolization with minimal risks. These results must be considered taking into account the nonrandomness of studies.

BACKGROUND: Recent literature highlights anomalous cranial nerves in the sinonasal region, notably in the sphenoid and maxillary sinuses, linked to anatomical factors. However, data on the suspended infraorbital canal (IOC) variant is scarce in cross-sectional imaging. Anatomical variations in the sphenoid sinuses, including optic, maxillary, and vidian nerves, raise interest among specialists involved in advanced sinonasal procedures. The infraorbital nerve\'s (ION) course along the orbital floor and its abnormal positioning within the orbital and maxillary sinus region pose risks of iatrogenic complications. A comprehensive radiological assessment is crucial before sinonasal surgeries. Cone-beam computed tomography (CBCT) is preferred for its spatial resolution and reduced radiation exposure.
OBJECTIVE: The aim of this study was to describe the prevalence of anatomical variants of the infraorbital canal (IOC) and report its association with clinical condition or surgical implication.
METHODS: We searched Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to June 2023. Two authors independently performed the search, study selection, data extraction, and assessed the methodological quality with assurance tool for anatomical studies (AQUA). Finally, the pooled prevalence was estimated using a random effects model.
RESULTS: Preliminary results show that three types are prevalent, type 1: the IOC does not bulge into the maxillary sinus (MS); therefore, the infraorbital foramen through the anterior wall of MS could be used for identification of the ION. Type 2: the IOC divided the orbital floor into medial and lateral aspects. Type 3: the IOC hangs in the MS and the entire orbital floor lying above the IOC. From which the clinical implications where mainly surgical, in type 1 the infraorbital foramen through the anterior wall of MS could be used for identification of the ION, while in type 2, since the lateral orbital floor could not be directly accessed an inferiorly transposition of ION is helpful to expose the lateral orbital wall directly with a 0 scope; or using angled endoscopes and instruments, however, the authors opinion is that direct exposure potentially facilitates the visualization and management in complex situations such as residual or recurrent mass, foreign body, and fracture located at the lateral aspect of the canal. Lastly, in type 3, the ION it\'s easily exposed with a 0° scope.
CONCLUSIONS: This systematic review identified four IOC variants: Type 1, within or below the MS roof; Type 2, partially protruding into the sinus; Type 3, fully protruding into the sinus or suspended from the roof; and Type 4, in the orbital floor. Clinical recommendations aim to prevent nerve injuries and enhance preoperative assessments. However, the lack of consistent statistical methods limits robust associations between IOC variants and clinical outcomes. Data heterogeneity and the absence of standardized reporting impede meta-analysis. Future research should prioritize detailed reporting, objective measurements, and statistical approaches for a comprehensive understanding of IOC variants and their clinical implications. Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/UGYFZ .

An in-depth understanding of the anatomy of the craniocervical junction (CCJ) is indispensable in skull base neurosurgery. In this paper, we discuss the osteology of the occipital bone, the atlas (C1) and axis (C2), the ligaments and the muscle anatomy of the CCJ region and their relationships with the vertebral artery. We will also discuss the trajectory of the vertebral artery and review the anatomy of the jugular foramen and lower cranial nerves (IX to XII). The most important surgical approaches to the CCJ, including the far lateral approach, the anterolateral approach of Bernard George and the endoscopic endonasal approach, will be discussed to review the surgical anatomy.

The purpose of this study was to review the diagnostic accuracy of MRI in detecting perineural spreading (PNS) of head and neck tumors using histopathological or surgical evidence from the afflicted nerve as the reference standard. Previous studies in the English language published in the last 30 years were searched from PubMed and Embase databases. We included studies that used magnetic resonance imaging (MRI) (with and without contrast enhancement) to detect PNS, as well as the histological or surgical confirmation of PNS, and that reported the exact numbers of patients required for assessing diagnostic accuracy. The outcome measures were sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Heterogeneity was assessed with the Higgins inconsistency test (I2). P-values smaller than 0.05 were considered statistically significant. A total of 11 retrospective studies were found, reporting 319 nerve samples from 245 patients. Meta-analytic estimates and their 95% confidence intervals were as follows: sensitivity 0.85 (0.70-0.95), specificity 0.85 (0.80-0.89), PPV 0.86 (0.70-0.94), and NPV 0.85 (0.71-0.93). We found statistically significant heterogeneity for sensitivity (I2 = 72%, p = 0.003) and PPV (I2 = 70%, p = 0.038), but not for NPV (I2 = 65%, p = 0.119) or specificity (I2 = 12%, p = 0.842). The most frequent MRI features of PNS were nerve enlargement and enhancement. Squamous cell carcinoma and adenoid cystic carcinoma were the most common tumor types, and the facial and trigeminal nerves were the most commonly affected nerves in PNS. Only a few studies provided examples of false MRI diagnoses. MRI demonstrated high diagnostic accuracy in depicting PNS of cranial nerves, yet this statement was based on scarce and heterogeneous evidence.

BACKGROUND: In patients with traumatic head injuries, the percentage of cranial nerve injuries (CNI) range from4.3 to 17.6% in which majority are isolated CNI[1-5].In present literature, moderate to severe types of head injuries are often studied which may result in a lack of representation and description of CNI associated with minor head injuries (MHI). Alongside this peculiar case of a traumatic cavernous sinus syndrome (CSS) that is non-thrombotic and non-fistulous in nature, this paper aims to analyse traumatic CNI in non-severe head injuries and the surrounding literature.
METHODS: A 65-year-old man who had sustained a minor head injury was found to have CNI of III, IV and VI.Brain imaging showed scattered traumatic subarachnoid haemorrhage and a non-displaced right zygomatic arch fracture. Despite the short course of high dose dexamethasone, he showed only partial recovery of his CNI after one year.
CONCLUSIONS: We present a case of traumatic CSS likely secondary to tractional injury from a MHI. Injury to the extraocular nerves wasfound to be one of the more commonly observed combination of CNI from the literature review conducted. In patients with MHI, multiple CNI is less common. Hence, consideration should be given to work upfor secondary causes such as tumours. There is presently no known clear identifiable pattern of CNI associated with MHI. CT brain findings of skull base fractures and early onset of cranial nerve palsies are generally associated with worse outcomes. More remains to be studied about tractional CNI in non-severe head injuries.

OBJECTIVE: The study aimed to summarize all published cases of intrinsic brainstem epidermoid cysts in a timeline to highlight the specific characteristics and individualize the disease, in addition to discussing the best treatment used.
METHODS: The scientific literature on pediatric cases of intrinsic epidermoid cysts of the brainstem was analyzed. We present the case of a 1.5-year-old male with incidental presentation, who was treated with gross total resection. We summarize all previously published cases to individualize the disease.
RESULTS: We identified 21 patients, including 10 boys and 11 girls, with a mean age of 4.85 (1-15) years at the time of surgery. The most frequent symptoms were cranial nerve palsy (71.4%), pyramidal tract deficit (57.14%), and headache (52.38%). Among the affected cranial nerves, VII was the most frequently reported in 10 patients.
CONCLUSIONS: Brainstem epidermoid cysts are extremely rare pathologies with relevant age involvement in young children. The treatment objective should be the maximum resection of the lesion through a careful approach and with the appropriate tools for the functional preservation of the patient.

OBJECTIVE: To investigate the effect of Bell\'s palsy (BP) presenting as polycranial neuropathy (PCN) compared with BP caused by isolated facial nerve (CNVII).
METHODS: We carried out a retrospective cohort study of the medical records of all consecutive patients who were diagnosed with BP at a single tertiary referral center between 2010 and 2017. Included were patients 18 years or older who were clinically diagnosed with BP and completed 7 days of systemic steroidal treatment and at least 6 months of follow-up. The patients were divided into two groups according to whether the BP derived from a monocranial neuropathy or a PCN. Demographics and BP severity and outcome were compared between these groups. A systematic literature review using Medline via \"PubMed,\" \"Embase,\" and \"Web of Science\" was conducted.
RESULTS: In total, 321 patients with BP were enrolled. The median (interquartile range) age at presentation was 44 (33-60) years. Sex distribution showed male predominance of 57.6% (n = 185) versus 42.4% (n = 136), and 21.2% (n = 68) had PCN. The most concomitantly affected cranial nerve (CN) was the trigeminal (CNV; n = 32, 47%), followed by the glossopharyngeal nerve (CNIX; n = 14, 21%) and the audiovestibular nerve (CNVIII; n = 10, 15%). Age, House-Brackmann score on presentation, and diabetes mellitus (DM) were independent predictors for PCN etiology ( p = 0.001, p = 0.034, and p < 0.001, respectively). Each increase in 1 year of age was associated with additional odds ratio (95% confidence interval) of 0.97 (0.95-0.99) for PCN. The odds ratio (95% confidence interval) associated with DM was 8.19 (4.02-16.70). Our systematic literature review identified 1,440 patients with the PCN type of BP. The most commonly affected CN was the trigeminus (25-48%), followed by the glossopharyngeal and audiovestibular nerves (2-19% and 0-43%, respectively).
CONCLUSIONS: The severity of facial weakness on initial presentation among PCN patients was significantly higher compared with the monocranial neuropathy-type BP patients. The authors believe that the significant association and prevalence rate ratio between DM and PCN warrant that a patient presenting with PCN undergo screening for DM.

Brainstem cavernous malformations (CMs) encompass up to 20% of all intracranial CMs and are considered more aggressive than cerebral CMs because of their high annual bleeding rates. Microsurgical resection remains the primary treatment modality for CMs, but long-term functional outcomes and complications are heterogenous in the literature. The authors performed a systematic review on brainstem CMs in 4 databases: PubMed, EMBASE, Cochrane library, and Google Scholar. We included studies that reported on the long-term functional outcomes and complications of brainstem CMs microsurgical resection. A meta-analysis was performed and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The search yielded 4781 results, of which 19 studies met our inclusion criteria. Microsurgery was performed on 940 patients (mean age 35 years, 46.9% females). Most of the brainstem CMs were located in the pons (n = 475). The pooled proportions of improved, stable, and worsened functional outcomes after microsurgical resection of brainstem CMs were 56.7% (95% CI 48.4-64.6), 28.6% (95% CI 22.4-35.7), and 12.6% (95% CI 9.6-16.2), respectively. CMs located in the medulla were significantly (p = 0.003) associated with a higher proportion of improved outcome compared with those in the pons and midbrain. Complete resection was achieved in 93.3% (95% CI 89.8-95.7). The immediate postoperative complication rate was 37.2% (95% CI 29.3-45.9), with new-onset cranial nerve deficit being the most common complication. The permanent morbidity rate was 17.3% (95% CI 10.5-27.1), with a low mortality rate of 1% from the compiled study population during a mean follow-up of 58 months. Our analysis indicates that microsurgical resection of brainstem CMs can result in favorable long-term functional outcomes with transient complications in the majority of patients. Complete microsurgical resection of the CM is associated with a lower incidence of CM hemorrhage and the morbidity related to it.

OBJECTIVE: Proton beam therapy is considered, by some authors, as having the advantage of delivering dose distributions more conformal to target compared with stereotactic radiosurgery (SRS). Here, we performed a systematic review and meta-analysis of proton beam for VSs, evaluating tumor control and cranial nerve preservation rates, particularly with regard to facial and hearing preservation.
METHODS: We reviewed, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) articles published between 1968 and September 30, 2022. We retained 8 studies reporting 587 patients.
RESULTS: Overall rate of tumor control (both stability and decrease in volume) was 95.4% (range 93.5-97.2%, p heterogeneity= 0.77, p<0.001). Overall rate of tumor progression was 4.6% (range 2.8-6.5%, p heterogeneity < 0.77, p<0.001). Overall rate of trigeminal nerve preservation (absence of numbness) was 95.6% (range 93.5-97.7%, I2 = 11.44%, p heterogeneity= 0.34, p<0.001). Overall rate of facial nerve preservation was 93.7% (range 89.6-97.7%, I2 = 76.27%, p heterogeneity<0.001, p<0.001). Overall rate of hearing preservation was 40.6% (range 29.4-51.8%, I2 = 43.36%, p heterogeneity= 0.1, p<0.001).
CONCLUSIONS: Proton beam therapy for VSs achieves high tumor control rates, as high as 95.4%. Facial rate preservation overall rates are 93%, which is lower compared to the most SRS series. Compared with most currently reported SRS techniques, proton beam radiation therapy for VSs does not offer an advantage for facial and hearing preservation compared to most of the currently reported SRS series.