Cerebellopontine angle craniopharyngioma in familial adenomatous polyposis.

Background: Craniopharyngiomas are benign tumors arising in the sellar and suprasellar regions. Although ectopic tumors do occur, it is usually due to local spread or recurrent tumors. Purely ectopic cerebellopontine angle (CPA) or 4th ventricle tumors are extremely rare and have been found to be significantly associated with familial adenomatous polyposis (FAP), a genetic disorder. Case Description: Only four cases of ectopic CPA craniopharyngioma associated with FAP have been reported to date. Here, we present the 5th case of ectopic CPA craniopharyngioma on a background of FAP. The previously described cases have been elaborated as well. Conclusion: CPA tumor with a background of FAP should raise a differential diagnosis of craniopharyngioma, and similarly, a CPA primary ectopic craniopharyngioma may raise suspicion of underlying APC gene mutation.

A Proposal for Comprehensive Audio-Vestibular Test Battery Protocol for Diagnosis and Follow-Up Monitoring in Patients with Vestibular Schwannoma Undergoing Surgical Tumor Removal.

Background: A vestibular schwannoma (VS) is a benign tumor, causing audiological and vestibular symptoms. This study aimed to propose a comprehensive audio-vestibular test battery protocol for diagnosis and follow-up monitoring in patients with unilateral VSs undergoing surgical removal. Methods: The detailed interpretation of audiological and vestibular findings was presented in two example cases. The surgery was performed through the middle cranial fossa (#1) and translabyrinthine approach (#2). The participants were evaluated with tonal, speech, and impedance audiometry, ABR, caloric test, vHIT, cVEMP, oVEMP, SOT, and DHI. Patient and tumor characteristics were retrieved from the patient's history. Results: In the postoperative period, the reduction in gain of the lateral semicircular canal was observed in the vHITs of both patients. The DHI in case #1 increased after surgery, while it decreased in case #2. The improvement in postural performances compared to the preoperative SOT (CON 5, CON 6, composite score) and immediately after the procedure was observed. Conclusions: A specific diagnostic protocol is necessary to compare the results of different surgical techniques and approaches. Diagnostic tests performed before the surgery should be repeated within a specific time frame during postoperative follow-up to enable the comparison of results. The proposed protocol can help us better understand the processes ongoing during tumor growth and postoperative vestibular compensation.

Consensus guidelines for the management of vestibular schwannoma for lowand middle-income countries.

Vestibular Schwannoma (VS), previously known as acoustic neuroma, constitutes the majority of tumours found in the cerebellopontine angle (CPA). Most guidelines for managing CPA tumours have been developed by high-income countries (HICs). However, these guidelines often fall short in addressing the unique challenges encountered in low- and middle-income countries (LMICs), such as Pakistan. In LMICs, issues related to a limited healthcare workforce, inadequate infrastructure, and constrained financial resources hinder the effective implementation of these HIC-derived guidelines. Additionally, it has been observed that VS tends to present at a larger size in LMICs compared to HICs. Given that VS is the predominant type of CPA tumour and other types are covered under separate guidelines, this article aims to provide practical, contextspecific recommendations for the screening, diagnosis, and management of Vestibular Schwannoma in LMIC settings. Our focus is to bridge the gap in care strategies and adapt them to the resource constraints and clinical realities of LMICs.

Functional outcomes after retrosigmoid approach to the cerebellopontine angle: Observations from a single-center experience of over 13 years.

Introduction: Accessing the posterior base of the skull is complex because of the vital neurovascular structures in the area. However, the retrosigmoid approach (RSA) offers a solution to this challenge. Research question: To analyze surgical outcome of RSA. Material and methods: This study involved a retrospective review of patient charts from a single center, focusing on the surgical procedure and outcomes following the operation. Results: The study included 517 patients suffering from conditions like vestibular schwannomas (VS), metastatic cancers, and trigeminal neuralgia. The most frequent symptoms reported were balance disorders (42.7%), hearing loss (36.5%), walking difficulties (21.2%), headaches (18.9%), facial pain (17.1%), issues with trigeminal nerve function (14.1%), cerebellar dysfunction (13.5%), and facial nerve paralysis (10.2%). The rate of complications stood at 21.1%, with 11.3% of patients needing revision surgery. The median score on the Clavien-Dindo scale was 2, and the rate of mortality related to surgery was 1.0%. Permanent symptom improvement was seen in 72.1% of cases. Temporary new deficits occurred in 43.2% of patients, with facial nerve paralysis being the most common (14.1%). No significant correlation was found between the size of the craniotomy and the extent of tumor resection (p = 0.155), except in the case of VS (p = 0.041). Larger craniotomy sizes were associated with higher rates of complications (p = 0.016), especially CSF leaks (p = 0.006). Complications significantly affected the likelihood and number of new deficits (p < 0.001 for both), particularly postoperative bleeding (p = 0.019, p = 0.001), CSF leaks (p = 0.026, p = 0.039), and hydrocephalus (p = 0.050, p = 0.007). Conclusions: The potential for complications related to the surgical approach cannot be overlooked. The size of the tumor should not dictate larger surgical approaches due to the associated increase in postoperative complications; a tailored approach that considers the precise tumor location and pathology is crucial for optimizing postoperative outcomes.

Intraoperative Transient Central Diabetes Insipidus Status Post-Cerebellopontine Meningioma Resection: A Case Report.

Central diabetes insipidus (CDI) is a neurological pathological condition in which vasopressin synthesis has been compromised. A 52-year-old male presented with a cerebellopontine angle mass not involving the hypothalamic-pituitary axis. Despite vasopressin therapy, the patient produced a total of 8650 mL of urine, with the urine-specific gravity measured at 1.002 near hour 8. A literature review found associations with certain anesthetic drugs that have an increased incidence of CDI, including alpha-2 agonists and sevoflurane. Reports have recommended administering desmopressin over vasopressin, especially for neurosurgery cases that warrant a more extended operative period, given that desmopressin has a longer context-sensitive half-life.

Schwannoma of the Lower Limb: A Case Report.

Schwannoma is a benign tumor of the peripheral nerve sheath and is a unique clinical entity when localized to a lower limb. Growing as a painless nodule, it might be misdiagnosed by many medical professionals as another benign soft tissue skin condition, such as lipoma, myxoma, or ganglion cyst. Definitive diagnosis of peripheral schwannoma is made by biopsy and histopathologic evaluation, followed by surgical excision, which is the definitive treatment of the tumor. Classic symptoms of schwannoma of the lower limb are peripheral neuropathy (tingling, burning sensations) and motor impairment (weakness, paralysis of the affected limb). MRI imaging and biopsy are the most useful diagnostic methods for peripheral schwannoma, followed by surgical excision, which is the treatment of choice. Postoperative complications, if present, are minimal and rare. Because of the slow-growing nature of the tumor and the complexity of the lower limb's nervous and structural network, it is often asymptomatic and is challenging to diagnose at a primary stage. That is why we want to spread awareness and draw the reader's attention to this rare case of a patient with schwannoma on the left lower limb.

AB087. Rectosigmoid approach for cerebellopontine angle tumors: what have we learned so far?

BACKGROUND: The cerebellopontine angle (CPA) is a multifaceted triangular region bordered by the brainstem medially, the cerebellum superiorly and posteriorly, and the temporal bone laterally. Tumors located in the CPA comprise 5% to 10% of all intracranial neoplasms, with vestibular schwannomas being the most prevalent, followed by meningiomas and epidermoid tumors. Various surgical approaches exist for removing these lesions, which consistently present challenges for neurosurgeons in effectively managing them. This study presents a case of a CPA tumor successfully treated via the retrosigmoid approach, followed by an assessment of the approach's efficacy and surgical outcomes. METHODS: A comprehensive literature search was conducted using electronic databases, including PubMed, ScienceDirect, and Google Scholar, to gather studies on surgically managed CPA tumors. In addition to reviewing the literature, we present a case study of a patient with CPA tumor who underwent surgery using the retrosigmoid approach. RESULTS: The literature review revealed that the retrosigmoid approach emerged as a commonly utilized technique, particularly for tumors in the CPA region. Analysis of the collected data indicated that the retrosigmoid approach offers several advantages, including excellent exposure of the CPA, minimal brain retraction, and reduced risk of injury to critical neurovascular structures. Moreover, studies consistently reported favorable surgical outcomes, with low rates of morbidity and mortality associated with this approach. In our case study, we successfully employed the retrosigmoid approach to resect a CPA tumor in a patient presenting with typical symptoms of spasticity in all four extremities and progressive hearing loss. CONCLUSIONS: In conclusion, the retrosigmoid approach remains a valuable surgical technique for the management of CPA tumors. This approach enhances the exposure of the CPA and increases the surgical angle of maneuverability. In most literature, the retrosigmoid approach provides adequate access that is safe and effective, with a low rate of postoperative complications. However, further prospective studies and comparative analyses are warranted to validate these findings and refine surgical techniques for optimizing patient outcomes.

Differences Among Elderly Patients Having Asymmetric Sensorineural Hearing Loss With and Without Cerebellopontine Angle Tumors.

Objective: Asymmetric sensorineural hearing loss (ASNHL) exhibits a higher prevalence among the elderly compared to younger individuals, yet optimal management remains subject to ongoing debate. We aimed to elucidate the clinical disparities among elderly patients with ASNHL, distinguishing between those with and without cerebellopontine angle (CPA) tumors. Methods: A retrospective analysis was conducted on elderly patients (aged ≥65 years) diagnosed with ASNHL who underwent magnetic resonance imaging (MRI) between January 2012 and December 2022 at our tertiary referral center. Results: A total of 119 patients were enrolled, with a median age of 71 years (range: 65-89 years). Among them, 11 patients (9.2%) exhibited abnormal MRI findings. In the CPA tumors group, vestibular schwannoma was the most prevalent abnormality (63.6%), with a mean growth rate of 0.53 mm/year (range: 0-1.33 mm/year). The prevalence of CPA tumors in patients with diabetes mellitus (DM) and ASNHL was significantly lower than in those without DM (P = .021). Vertigo emerged as a significant associated symptom in cases with CPA tumors (P = .011). However, there were no significant differences in mean hearing thresholds or asymmetry of hearing loss at individual frequencies between the 2 groups. Conclusions: Elderly patients with ASNHL and vertigo should undergo radiological assessment. Patients with DM exhibit a lower prevalence of CPA tumors than those without DM, warranting careful observation and follow-up due to the limited diagnostic yield of MRI. No discernible differences in audiometric patterns were detected between patients with and without CPA tumors.

Utility of cone beam computed tomography for rare temporal bone lesion: A case report.

This case report aims to describe the clinical presentation, imaging findings, diagnostic challenges, and management of a patient with a cerebellopontine angle lesion. A 63-year-old woman presented with progressive headaches, tinnitus, right ear pressure, and dizziness. Initial imaging studies (computed tomography and magnetic resonance imaging) suggested either a thrombosed aneurysm or a lipoma. However, advanced imaging with cone beam computed tomography provided a definitive diagnosis of temporal bone exostosis. This case highlights the importance of cone beam computed tomography in diagnosing complex intracranial lesions due to its superior spatial resolution and lower radiation dose.

Posterior Fossa Ependymoma in a Child with Extensive Chondro-Osseous Metaplasia Occurring at Cerebellopontine Angle and Masquerading as a Vestibular Schwannoma: An Exceptionally Rare Clinicopathological Manifestation with Review of Literature.

Ependymoma occurring at the cerebellopontine (CP) angle is an extremely uncommon sight and poses diagnostic and management dilemmas to neurosurgeons, radiologists, and neuropathologists alike. Moreover, the presence of extensive chondro-osseous metaplastic elements in ependymomas is an exceptionally infrequent histopathological manifestation. However, due to the seldom-seen nature of this histomorphological feature, there is no definite consensus regarding its etiopathogenesis and clinical consequences, and there is an extreme scarcity of literature elucidating its clinicopathological spectrum and prognostic significance. Herein, we illustrate an intriguing clinical tale of a 7-year-old male child with posterior fossa ependymoma, central nervous system (CNS) World Health Organization (WHO) grade 3, arising at the right CP angle and masquerading as a vestibular schwannoma, which in itself is a rare presentation, and additionally, exhibiting extensive chondro-osseous metaplasia, which is a very uncommon histomorphological observation. To the best of the authors' knowledge and after a comprehensive literature search, the coexistence of these two rare observations has merely been described once in international literature. This case sheds light on and highlights the importance of keeping ependymoma as a possible differential while coming across CP angle space-occupying lesions. They should be diligently distinguished from schwannomas and other masqueraders that typically occur at this site, as they have diverse management and follow-up protocols, with varying prognostic outcomes for the patients. Moreover, this case also unravels and details the clinicopathological characteristics of a scarcely described feature of chondro-osseous metaplasia in ependymomas.

The predictive value of intraoperative facial motor evoked potentials in cerebellopontine angle tumor surgery.

OBJECTIVE: Our aim is to explore the value of intraoperative facial motor evoked potentials (FMEP) for facial outcomes in cerebellopontine angle (CPA) tumor surgery to provide an evidence-based consensus standard for future clinical practice and prospective studies. METHODS: Electronic databases were searched from inception to June 2023. Study quality was assessed with the QUADAS-2 tool. Bivariate and random-effects models for meta-analysis and meta-regression generated summary receiver operating characteristic curves (ROC) and forest plots for estimates of sensitivity and specificity. RESULTS: We included 17 studies (1,206 participants). Sensitivity was lower in the immediate (IM) post-operative (0.76, 95% CI 0.65-0.84) compared to follow-up (FU) period (0.82, 95% CI 0.74-0.88) while specificity was similar in both groups (IM, 0.94, 95% CI 0.89-0.97; FU, 0.93, 95% CI 0.87-0.96). Data driven estimates improved FMEP performance but require confirmation from future studies. Amplitude cutoff criteria and studies that scored new deficits as worse than House-Brackmann (HB) grade 2 yielded best sensitivities. CONCLUSIONS: FMEP demonstrated statistically significant accuracy for facial function monitoring. Implementation of FMEPs varied widely across studies. SIGNIFICANCE: Our study is the first systematic review with meta-analysis to demonstrate that intraoperative FMEP is valuable in CPA tumor surgery for facial outcomes. Meta-regression identified the methods that were most useful in the application of FMEPs.

A minimally invasive endovascular approach to the cerebellopontine angle cistern enables broad CNS biodistribution of scAAV9-CB-GFP.

Neurological disorders pose a challenge for targeted therapy due to restricted access of therapeutic agents to the central nervous system (CNS). Current methods are limited by procedure-related risks, invasiveness, and insufficient CNS biodistribution. A novel percutaneous transvenous technology, currently in clinical trials for communicating hydrocephalus, offers a minimally invasive approach by providing endovascular access to the cerebrospinal fluid-filled cerebellopontine angle (CPA) cistern. We hypothesized that drug delivery to the CPA cistern could yield widespread CNS distribution. Using an ovine model, we compared the biodistribution of scAAV9-CB-GFP following CPA cistern infusion with previously reported cisterna magna (CM) administration. Targeting both the CPA cistern and CM in sheep, we employed a lumbar spine-inserted microcatheter under fluoroscopy. CPA delivery of AAV9 demonstrated biodistribution and transduction in the cerebral cortices, striatum, thalamus, midbrain, cerebellum, and spinal cord, with minor liver distribution comparable to CM. The favorable safety profile in humans with hydrocephalus suggests that percutaneous endovascular injection into the CPA could offer a clinically safer and minimally invasive delivery system for CNS gene and cell-based therapies.

Creeping through the cranium: A rare and interesting presentation of a meningioma.

A meningioma is a rare primary CNS tumor that tends to present more so in females in a slowly progressive fashion. The cavernous sinus and cerebellopontine angle are uncommon locations for meningiomas. We present a case of a meningioma in a 60-year-old female presenting to the emergency department for a sudden onset headache, vertigo, facial paresthesias, and chest pain. Inpatient workup revealed orthostatic hypotension, a meningioma spanning from the left cavernous sinus to the left cerebellopontine angle encasing the left cavernous internal carotid artery on MRI and CTA, and an incidental 12 mm calcified fibroadenoma on CT. Hospital course consisted of supportive treatment, physical rehabilitation, and review of previous imaging to determine need for intervention per consultants' recommendations. The patient was discharged with an antiplatelet, an antihistamine, appropriate additional medications, a vestibular therapy script, and outpatient referrals for a decision regarding surveillance and intervention. Overall, this case describes some key points. It demonstrates that cavernous sinus and cerebellopontine angle meningiomas can occur simultaneously, especially as a continuous mass, which very few cases have done so far. It also highlights an acute clinical presentation of a meningioma, contrary to the gradually progressive one observed in most instances. Last, but not least, it shows how nonspecific symptoms can lead to unique findings at times.

Fully Endoscopic Retrosigmoid Approach for Cerebellopontine Angle Tumors.

BACKGROUND: Fully endoscopic or endoscope-controlled approaches are essentially keyhole approaches in which rigid endoscopes are the sole visualization tools used during the whole procedure. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Fully endoscopic retrosigmoid approach for cerebellopontine angle tumors is a minimally invasive approach that is not routinely practiced by neurosurgeons, with few series published so far. Unfamiliarity with the technique, steep learning curve, and concerns about inadequate exposure, neurovascular injury, and decreased visibility may explain this fact. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic retrosigmoid approach and present an overview of the published series. METHODS: From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases undergoing fully endoscopic retrosigmoid approach for cerebellopontine angle tumors were retrieved and analyzed. The pertinent literature was also reviewed. RESULTS: The surgical technique of the fully endoscopic retrosigmoid approach was formulated. CONCLUSION: The endoscopic technique has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.

Magnetic resonance imaging of the cerebellopontine angle: comparison between constructive interference steady-state and small field-of-view technique turbo spin echo sequences.

BACKGROUND: The aim of this work was to optimize a three-dimensional (3D) turbo-spin-echo (TSE) sequence using a small field-of-view (FOV) technique for the study of the cerebellopontine angle and to compare it with a constructive interference steady-state (CISS) sequence. METHODS: A total of 30 consecutive patients underwent magnetic resonance imaging with a 3Tesla (T) scanner, including 3D CISS and the optimized 3D small FOV technique turbo spin echo (3D SFT-TSE) T2-weighted sequences for the study of the cerebellopontine angle. The 3D SFT-TSE sequence was optimized after three different steps, and a quantitative evaluation of the signal-to-noise ratio (SNR) was obtained according to the National Electrical Manufacturers Association (NEMA) method. Three neuroradiologists made a blind comparative qualitative evaluation of the images between the 3D CISS and the 3D SFT-TSE obtained after the third optimization step, based on spatial resolution, contrast resolution, and presence of artifacts and noise. RESULTS: The calculation of SNR using the NEMA method confirmed the superiority of the third optimization step over the others. For both spatial and contrast resolution, the optimized SFT-TSE was considered better (p < 0.001) than the CISS, while image artifacts and noise were considered worse in the CISS sequence (p < 0.001). Intraobserver analysis showed that all neuroradiologists preferred the 3D SFT-TSE sequence in terms of both spatial resolution and contrast resolution and found more noise and artifact disruption in the CISS sequence. CONCLUSIONS: The use of the 2D radiofrequency pulse technique with a 3D SFT-TSE T2 sequence was significantly more efficient than the 3D CISS sequence for the study of the cerebellopontine angle and inner ear structures.

Clinicopathological characteristics of secondary trigeminal neuralgia due to cerebellopontine angle tumors. / æ¡¥å°è„‘è§’è‚¿ç˜¤ç»§å‘æ€§ä¸‰å‰ç¥žç»ç—›çš„ä¸´åºŠç— ç†ç‰¹å¾.

OBJECTIVES: Cerebellopontine angle (CPA) tumors are a common cause of secondary trigeminal neuralgia (TN), characterized by their concealed location, slow progression, and difficulty in early detection. This study aims to explore the clinicopathological characteristics of patients with secondary TN due to CPA tumors to enhance understanding and management of secondary TN. METHODS: A retrospective analysis was conducted on clinical data and pathological results of 116 patients with CPA tumor-related TN treated at Xiangya Hospital of Central South University from January 1, 2017 to December 31, 2022. The study analyzed the relationship of tumor pathological types with clinical manifestations, tumor location, surgical methods, and treatment outcomes. RESULTS: Among the cases, 95.7% (111/116) were benign tumors, 3.4% (4/116) were malignant tumors, and 0.9% (1/116) were borderline tumors. Benign tumors were predominantly acoustic neuromas, meningiomas, and schwannomas. Among the patients, 46.6% (54/116) presented with isolated TN, while 53.4% (62/116) exhibited other associated symptoms depending on factors such as tumor growth location and rate. The complete resection rate in this group was over 90%, with 41.4% (48/116) of patients undergoing concurrent microvascular decompression after tumor resection, predominantly for schwannomas. The overall effective rate of surgical treatment reached 93.9%, with schwannomas showing higher efficacy rates compared with acoustic neuromas and meningiomas (P<0.05). The recurrence rate of acoustic neuromas was significantly higher than that of meningiomas and schwannomas (P<0.05). CONCLUSIONS: CPA tumors are a major cause of secondary TN, predominantly benign, with occasional underdiagnosed malignant tumors. Early diagnosis and treatment significantly impact prognosis. Different tumor types vary in clinical symptoms, surgical approaches, and treatment efficacy. Surgical strategies should balance tumor resection extent and neural function preservation, with microvascular decompression as necessary.

Surgical Outcomes and Predictive Factor Analysis for Facial Nerve Preservation in Patients With Cerebellopontine Angle (CPA) Tumors: A Ten-Year Single Institutional Study.

Objective To analyze the surgical outcome and predictive factors for facial nerve preservation in patients with surgically operated cerebellopontine angle (CPA) tumors. Methodology Methodology Data were retrospectively retrieved from inpatient medical records of patients admitted with CPA tumors from January 1, 2011, to December 31, 2020, at our institute. Epidemiological, clinical and radiological findings, histopathological types, surgical outcomes, and facial nerve function of these patients were recorded using a data-gathering tool. Results Out of 230 patients, 188 (81.7%) were diagnosed histopathologically with vestibular schwannoma (VS), 20 (8.7%) with meningioma, 15 (6.5%) with epidermoid, and 7 (3.1%) with other conditions. The most common clinical features were hearing loss in VS and headaches in meningioma and epidermoid. Preoperatively, 103 (44.8%) had grade 2, 68 (29.6%) had grades 3 or 4, and 8 (3.5%) had grade 5 facial nerve palsy, while post-operatively, 93 (40.9%) patients had grade 2, 83 (36.6%) had grades 3 or 4, and 6 (2.6%) had grade 5 facial palsy. Greater facial nerve preservation was observed in patients with tumor sizes <4 cm (p=0.0041) and in those who underwent near-total (NTR) or subtotal resection (STR) (p=0.0442). Excellent facial nerve outcomes (HB grades 1 or 2) were noted in patients who underwent intraoperative facial nerve monitoring (p<0.0001). CSF leak and meningitis were present in 3.5% and 2.2% of patients, respectively. The mortality rate was 6.1%, with a recurrence rate of 4.8%. Conclusion Intraoperative facial nerve monitoring, tumor size less than 4 cm, and extent of resection (NTR/STR) are predictive factors that significantly affect facial nerve outcomes.

Prevalence of Anterior Inferior Cerebellar Artery Vascular Loop in Cerebellopontine Angle With Three-Dimensional Constructive Interference in Steady State (CISS) Sequence MRI.

Background The cerebellopontine angle (CPA) cistern houses vital neurovascular structures such as cranial nerves V, VII, and VIII and the anterior inferior cerebellar artery (AICA), often leading to neurovascular compression syndromes due to its complex anatomy. Although vascular compression is a recognized cause of certain neuralgias, its association with otologic symptoms such as tinnitus, hearing loss, and dizziness remains uncertain. Hence, this study aims to determine the prevalence of the AICA vascular loop in the CPA cistern on MRI in patients with asymptomatic audiovestibular symptoms. Methodology Adult patients who underwent MRI, including the posterior fossa's high-resolution volumetric T2 sequence (three-dimensional constructive interference in steady state (3D-CISS)), were assessed. Patients with a history of audiovestibular symptoms (tinnitus/dizziness/vertigo/sensorineural hearing loss), intracranial tumor, vascular lesions, intracranial surgery, brain radiation therapy, traumatic brain injury, poor image quality, and MRI scans without 3D-CISS sequences were excluded. Two radiologists independently reviewed 114 (228 sides) MRI studies for the vascular loop of AICA in the CPA cistern and the extension of the AICA loop into the ipsilateral internal acoustic meatus which was graded by Chavda's classification. Results The prevalence of vascular loop of AICA in the CPA cistern was as high as 47.6% in asymptomatic patients. Grade I Chavda vascular loop was the most common type followed by type II, with type III being the least common type. Conclusions Knowledge regarding the high prevalence of the AICA loop in the asymptomatic population and the lack of significant correlation between the presence of the AICA loop and otovestibular symptoms should be considered in preoperative planning for decompression procedures.

A Case Report of Malignant Cerebellopontine Angle Lesion Highlighting the Interdisciplinary Diagnostic Challenge in the Case of Unilateral Progressive Hearing Loss.

The authors present the case of a young boy who experienced progressive unilateral hearing loss initially believed to be unrelated to any other medical condition. Methods: The patient received a thorough evaluation, which included a comprehensive battery of audiological tests, a CT scan, and a gadolinium-enhanced MRI. Results: A repeated imaging investigation revealed the presence of a mass that mimicked a vestibular schwannoma (VS), but despite this, the boy was ultimately diagnosed with cerebral manifestations of B-cell acute lymphoblastic leukemia (B-ALL). Conclusions: Cerebral lesions originating from the internal auditory canal are rare in cases of B-ALL. In this case, the initial signs and symptoms of the disease were solely related to the audiovestibular system, making the diagnostic process particularly complicated. Unilateral hearing loss cases may indicate the presence of potentially life-threatening conditions, even if the hearing loss appears to be clinically non-syndromic. For these reasons, unilateral hearing losses necessitate a comprehensive interdisciplinary diagnostic approach from the very start of auditory manifestation and, in particular, if the hearing impairment demonstrates threshold progression.

Role of Neuroradiological Imaging in Progressive Sensorineural Hearing Loss: A Retrospective Study.

Aim: Our aim was to determine prevalence and type of neuro-radiological lesions detected on screening Magnetic Resonance Imaging (MRI) of brain in patients presenting with progressive sensorineural hearing loss in otorhinolaryngology clinic. Materials and Methods: This retrospective study included 96 screening magnetic resonance imaging MRI brain scans of patients who presented with progressive sensorineural hearing loss in department of otorhinolaryngology. The clinical and radiological data was collected and analysed. Results: Out of 96 screening MRI brain, 19 (19.8%) had positive findings. The commonest imaging finding was presence of vascular loop around facial and vestibulocochlear nerve root complex in 9 cases (9.4%) followed by presence of a cerebellopontine angle lesions in 5 cases (5.2%). The mean age of all patients was 48.5 years and those with positive screening MRI was 40.6 years. A gender gap was noticed with female being 22 (22.9%) in number against 74 (77.1%) males. Conclusion: This is the first retrospective study to determine prevalence and type of neuro-radiological lesions detected on screening magnetic resonance imaging in patients with progressive sensorineural hearing loss. We recommend screening MRI brain in patients with progressive SNHL aged below 60 years and all the described neuroradiological finding provide differential diagnosis. Definition and classification of progressive sensorineural hearing loss should be formulated to standardize the management. Further multi-institutional studies are required to identify social, occupational, genetic, or other factors that can cause gender disparity in patients with progressive SNHL.