Cerebellopontine Angle Epidermoids Research Articles

The endoscopic-assisted approach versus the microscopic only approach in resection of cerebellopontine angle epidermoids: a 5-year retrospective study

BackgroundThe endoscopic-assisted technique has been utilized with various intracranial lesions with many approaches. In the cerebellopontine angle (CPA), the technique has been used to combine the benefits of the operating microscope and the endoscope. In this study, we highlight the use of the endoscopic-assisted technique in resection of CPA epidermoid tumors to ensure a total resection, decrease complications and protect the neurovascular tangles.ResultsIn the endoscopic-assisted group, only 18.8% of the patients had post-operative residual in the post-operative MRI. However, in the microscopic only group 56.3% of the patients had post-operative residual. Consequently, there is a statistically significant difference regarding the post-operative residual between the two groups.ConclusionsThe endoscopic-assisted approach is superior to the microscopic only approach in the excision of CPA epidermoids and minimizing the post-operative residual and the recurrence.

Cerebellopontine Angle Epidermoids: Comparative Results of Microscopic and Endoscopic Excision Using the Retromastoid Approach".

Background Densely packed neurovascular structures, often times inseparable capsular adhesions and sometimes a multicompartmental tumor extension, make surgical excision of cerebellopontine angle epidermoids (CPEs) a challenging task. A simultaneous or an exclusive endoscopic visualization has added a new dimension to the classical microscopic approaches to these tumors recently. Methods Eighty-six patients (age: 31.6 ± 11.7 years, M:F = 1:1) were included. Nineteen patients (22.1%) had a multicompartmental tumor. Tumor extension was classified into five subtypes. Sixty-two patients underwent a pure microscopic approach (72%) out of which 10 patients (16%) underwent an endoscope-assisted surgery (11.6%) and 24 patients (28%) underwent an endoscope-controlled excision. Surgical outcomes were retrospectively analyzed. Results Headache (53.4%), hearing loss (46.5%), and trigeminal neuralgia (41.8%) were the leading symptoms. Interestingly, 21% of the patients had at least one preexisting cranial nerve deficit. Endoscopic assistance helped in removing an unseen tumor lobule in 3 of 10 patients (30%). Pure endoscopic approach significantly reduced the hospital stay from 9.2 to 7.3 days ( p = 0.012), and had a statistically insignificant yet a clearly noticeable lesser incidence of subtotal tumor excision (0 vs. 10%, p = 0.18) with comparable cranial nerve deficits but with a higher postoperative cerebrospinal fluid (CSF) leak rate (29% vs. 4.8%, p = 0.004). Conclusion Endoscope assistance in CPE surgery is a useful addition to conventional microscopic retromastoid approach. Pure endoscopic excision in CPE is feasible, associated with a lesser duration of hospital stay, better extent of excision in selected cases, and it has a comparable cranial nerve morbidity profile albeit with a higher rate of CSF leak.

Surgical management of cerebellopontine angle epidermoid cysts: an institutional experience of 10 years

Background Cerebellopontine angle (CPA) epidermoids, although of benign nature, are of considerable neurosurgical interest because of their close proximity and adherence to the cranial nerves and brain stem. In this paper, we describe our experience and attempt to correlate the final outcomes with the extent of surgical removal. The main objectives were to study various modes of surgical management of CPA epidermoids with regard to removal and preservation of the cranial nerves and also to evaluate the role of endoscopic assisted microsurgical excision thereby minimizing recurrences. This case series is one of the largest series reported so far worldwide. Materials and methods From 2006 to 2016, 139 patients with CPA epidermoids were operated at Grant Medical College and J. J. Hospital, Mumbai. All patients underwent detailed magnetic resonance imaging (MRI) of brain. Lesions were classified according Rogelio Revuelta-Gutiérrez et al. with respect to their anatomic extent: grade I- within the boundaries of the CPA, grade II- extension to the suprasellar and perimesencephalic cisterns, and grade III-parasellar and temporomesial region involvement. Retrosigmoidal and sub temporal approaches were taken to excise the lesions. Endoscopic assisted microsurgical excision was done in cases with extensions beyond the CPA. Patient follow-up was based on outpatient repeated brain MRI studies. Results The mean duration of symptoms before surgery was 42 months (range, 2 months to 6 years). The mean follow-up period was 27 months (range, 2–60 months). The main presenting sympt om was headache in 69% (96/139) of the cases and trigeminal neuralgia in 30% cases was the second most common cause of consultation. Seventy-five percent of patients had some degree of cranial nerve (CN) involvement. Retrosigmoid approach was taken in 92% patients and 7 patients with supratentorial extension were operated by combined retrosigmoidal and subtemporal approach. Endoscopic assisted microsurgical excision was done in 40% cases. Use of angled views by an endoscope helped to excise residual tumor in 47 (83%) patients. Complete excision was achieved in 67% of cases. In 33% patients, small capsular remnants could not be removed completely because of their adherence to vessels, brainstem and cranial nerves. Compared with their preoperative clinical status, 74% improved and 20% had persistent cranial nerve deficits in the first year of follow up. Conclusions Epidermoid cysts are challenging entities in current neurosurgery practice due to tumor adhesions to neurovascular structures. Meticulous surgical technique with the aid of neurophysiological monitoring is crucial to achieve safe and effective total or subtotal removal of these lesions. A conservative approach is indicated for patients in whom the fragments of capsule is adhered closely to blood vessels, nerves, or the brainstem, in order to avoid risk of serious neurological deficits related to an inadvertent damage of these structures. Use of angled views by endoscope at the conclusion of the surgery may assure the surgeon of total removal of the tumor.

Evaluation of Cerebellopontine Angle Epidermoid Presenting with Cranial Nerve Deficit: A Surgical Perspective.

Context:Cerebellopontine angle (CPA) epidermoids are essentially benign tumors, and treatment is complete surgical excision.Aims:The aim of this study was to evaluate the surgical perspective and outcome analysis of CPA epidermoids.Settings and Design:This was a retrospective cohort study.Subjects and Methods:This study includes a cohort of 15 patients operated for CPA epidermoid in the Department of Neurosurgery of Institute of Medical Sciences, Banaras Hindu University, Varanasi, India, between August 1, 2016, and January 31, 2020. Each patient was evaluated in terms of demographic profile, clinical presentation, surgical management, and postoperative outcome characteristics.Statistical Analysis Used:Unpaired t-test and Chi-square test were used for analysis. Values with P < 0.05 were considered statistically significant. Statistical tests were done using GraphPad Prism version 8.3.0 software.Results:The mean age was 43 years, with the majority of patients being female (56.5%). The most common cranial nerve (CN) involved was CN VIII (67.7%), followed by CN VII (60%). Persisting CN deficit (P = 0.0118) was significantly (P < 0.05) associated with subtotal resection (STR). Gross-total resection was significantly associated (P < 0.05) to CN VII (P = 0.0233) and VIII (P = 0.0157) recovery.Conclusions:The extent of the tumor excision had no effect on the postoperative morbidity and the risk of recurrence. STR can be considered when there is dense adherence to blood vessels, nerves, or the brain stem to prevent the risk of serious neurological deficits. STR is significantly associated with persisting CN deficit postoperatively. During long-term follow-up, resolution or improvement of neurological deficits may be expected in most patients.

Clinical, radiological and microneurosurgical aspects in the management of intracranial epidermoid cysts: Experience with 38 cases

Objectives: There is considerable debate in the surgical management of epidermoid cyst whether gross total or subtotal resection yields better long term outcomes. We present our institutional experience in evaluating the clinical presentation, diagnosis and surgical strategy and extent of resection in the management of intracranial epidermoid cyst.Methods: We retrospectively reviewed the case records of 38 patients with intracranial epidermoid tumors surgically treated at our institution between 2010 and 2019.Results: A total of 38 patients who underwent surgery for intracranial epidermoid lesions were identified. Of these 17 were supratentorial, 20 were infratentorial lesions and one case lesion was extending from cerebellopontine region to middle fossa. The mean duration from onset of symptoms to surgery was 3.9 years. Cranial nerve dysfunction was noted in 73% of patients preoperatively most of them being the Cerebellopontine angle epidermoids. Total removal was achieved in 28 patients, near-total removal in 8 patients, and subtotal removal in 2 patients. 6 patients developed recurrence radiologically of them only one patient became symptomatic. Of the six 2 were patients who underwent gross total resection and the remaining 4 were from near and subtotal resection. The mean duration of follow-up was 3.8 years. The content of the tumor was pearly white/white material in all cases. complications noted in the present series were not related to the completeness of excision. Mortality was noted in one patient.Conclusions: The present study highlights various precautions to be taken intraoperatively in the prevention of development of aseptic meningitis and concludes that total removal of epidermoids does not result in significantly increased morbidity and mortality and should be the goal of surgical treatment. However, near/subtotal resection oflesions that are densely adherent to neurovascular structures is justified, as there is no significant difference in the rate of recurrence. An endoscope can be used to assess the completeness of surgery.

Temporal Bone and Cerebellopontine Angle Epidermoid Resulting in Facial Nerve Paralysis: Resection and Facial Nerve Coaptation.

Objectives Demonstrate the utilization of a transcochlear approach for resection of an epidermoid involving the temporal bone and cerebellopontine angle (CPA) with end-to-end facial nerve coaptation. Designs Single case-based operative video. Setting Tertiary center with dedicated skull base team. Participants The patient is a 50-year-old left handed male with a history of a remote left Bell's palsy, left sudden sensorineural hearing loss, and a rapidly progressive facial nerve paralysis. His balance was impaired, and his videonystagmography showed a significant left sided peripheral vestibular weakness. Computed tomography (CT) scan showed an erosive lesion of his left temporal bone involving the cochlea and semicircular canals, and magnetic resonance imaging (MRI) showed a T2 hyperintense lesion with restricted diffusion and no enhancement on postcontrast T1 sequences. Main Outcome Measures Gross total resection of the epidermoid, recovery of facial nerve function, balance improvement. Results The patient underwent resection via a transcochlear approach. The tumor involved the epitympanum and eroded the semicircular canals, vestibule, and basal turn of the cochlea. Gross total tumor resection was attained. The facial nerve was isolated in the mastoid and tympanic segments, traced proximally to the geniculate ganglion, and then into the internal auditory canal (IAC). The nerve was discontinuous in the distal IAC and a reactive neuroma was resected. The facial nerve was mobilized and an end-to-end coaptation was performed in the CPA using a collagen tubule. The 3-month postoperative MRI showed no residual or recurrent disease. His postoperative balance was improved. Partial facial nerve recovery is not expected prior to 9 to 12 months. The link to the video can be found at: https://youtu.be/C6N8qPwBt2Y .

Primary Epidermoid Tumors of the Cerebellopontine Angle: A Review of 47 Cases.

To analyze disease presentation, treatment, and clinical course of a consecutive series of patients with primary cerebellopontine angle (CPA) epidermoids. Forty-seven consecutive patients with previously untreated CPA epidermoids. Observation and microsurgery. Disease- and treatment-associated morbidity, recurrence. Forty-seven patients (mean age 39 years; 53% women) were analyzed and the average duration of follow-up was 42 months. The most common presenting symptom was headache (27; 57%); 13 (28%) exhibited preoperative asymmetric sensorineural hearing loss, 3 (6%) facial nerve paresis, and 3 (6%) hemifacial spasm. Thirteen patients (28%) were initially observed over a mean interval of 56 months; however, five experienced disease progression requiring operation. Thirty-nine patients (83%) underwent surgical resection; 18 (46%) received gross total, 5 (13%) near total, and 16 (41%) aggressive subtotal resection. Three patients (8%) recurred at a median of 53 months; two after subtotal and one after gross total resection. Ninety-three percent of patients with useful hearing maintained serviceable hearing following treatment and one patient (3%) experienced mild long-term postoperative facial nerve paresis (HB II/VI). All patients with preoperative facial nerve paresis recovered normal function postoperatively. There were no episodes of stroke or death. Surgical intervention is effective in alleviating symptoms of cranial neuropathy and brainstem compression from CPA epidermoids. Gross total resection is preferred; however, aggressive subtotal removal should be considered with adherent or extensive disease as reoperation rates are low, even in the setting of aggressive subtotal resection. Conservative observation with serial imaging is a viable initial strategy in asymptomatic or minimally symptomatic patients.

Epidermoid cysts of the cerebellopontine angle: Clinical features and treatment outcomes

ObjectiveTo report clinical characteristics, treatment outcomes and risk of recurrence in patients with surgically treated cerebellopontine angle epidermoids. MethodsIn 1994–2013, we operated 17 patients, including 7 with tumor limited to the cerebellopontine angle, 7 with cerebellopontine angle tumor penetrating supratentorially, and 3 with cerebellopontine angle tumor extending along skull base to contralateral cerebellopontine angle. All patients were followed-up for the mean duration of 126 months. ResultsOn admission cranial nerve symptoms predominated. Total tumor removal was achieved in 5 patients, and incomplete removal (with small tumor remnants left on vessels, nerves, or brainstem) in 12 patients. Postoperatively, preoperative deficits worsened in 2 and new postoperative deficits occurred in 10 patients. The extent of tumor expansion had no effect on postoperative morbidity and risk of recurrence. During long-term follow-up, improvement or resolution of preoperative deficits was seen in 11 of 17 patients, and new postoperative deficits in 8 of 10 patients. Symptomatic recurrences after an average of more than 9 years were noted in 5 patients, 3 of whom were reoperated. Recurrences occurred in some younger patients and always in area of primary tumor. No effect of extent of tumor removal on risk of recurrence was found. ConclusionsThe extent of tumor removal had no effect on the risk of recurrence, and thus it may be acceptable to leave tumor capsule fragments adhering closely to nerves, vessels, or brainstem. During long-term follow-up, resolution or improvement of present preoperatively and new postoperative neurological deficits may be expected in most patients.

Pure endoscopic removal of epidermoid tumors of the cerebellopontine angle

Epidermoid tumors located in the cerebellopontine angle (CPA) are challenging lesions because they tend to grow slowly in the subarachnoid cisterns around delicate neurovascular structures and often extend into surgical anatomic corners. The aim of this paper is to demonstrate the advantages and limitations of purely endoscopic removal of the CPA epidermoids. Six patients harboring an epidermoid tumor located in the CPA were treated using an endoscope-controlled microsurgical technique. A retrosigmoid suboccipital approach was used in all patients. The cerebellomedullary cistern and the cisterna magna were opened to allow cerebrospinal fluid drainage and cerebellar drop, thus yielding a wide and straight working channel to the CPA. Then, the tumor and its capsule were removed by the modified microsurgical instruments. The symptoms caused by mass effect of the lesion resolved after surgery. There were no deaths, but permanent deficits occurred in one patient whose cranial nerves VII/VIII complex was accidentally lesioned. Tumors and their capsules were totally removed in five cases. All patients were discharged 3-5days after surgery. To date, no recurrences have been observed (follow-up range 14-50months). The endoscope-controlled microsurgical technique enables a safe tumor removal even when parts of the lesion are not visible in a straight line in CPA epidermoids. By angled endoscopic lenses, tumor extending into adjacent cranial compartments or surgical anatomic corners can be removed through a single small craniotomy without retracting neurovascular structures.

Long term outcome in surgically treated posterior fossa epidermoids

ObjectivesTo study posterior fossa epidermoids treated surgically at our institute and to compare their long term outcome with respect to extent of surgical decompression. Materials and methodsRetrospective analysis of 50 cases of posterior fossa epidermoid surgically treated at our institute between 1997 and 2007. ResultsThe mean duration from onset of symptoms to surgery was 2.5 years. Patients with cerebellopontine angle (CPA) epidermoids presented predominantly with trigeminal neuralgia (35%) and hearing loss (29%) while patients with fourth ventricle epidermoids had features of raised intracranial pressure (ICP) and gait ataxia (69.2% each). The rate of recurrence was 9% in tumors considered totally removed and 93% in those subtotally removed. Of the 17 patients with recurrences, 3 (7.9%) underwent a second operation. The mean duration of follow up at first recurrence was 9.3 years. ConclusionBased on our experience, the rate of recurrence is significantly higher after subtotal removal as compared to total removal of epidermoids on long-term follow up. Symptomatic recurrence requiring re-exploration is evident only after a long duration (∼10.9 year) following primary surgery. Hence, total removal without producing new neurological deficits should be the standard goal when operating on posterior fossa epidermoid cysts.

Squamous Cell Carcinoma Arising in a Remnant of an Extirpated Cerebellopontine Angle Epidermoid Tumor: Case Report and Literature Review

Squamous Cell Carcinoma Arising in a Remnant of an Extirpated Cerebellopontine Angle Epidermoid Tumor: Case Report and Literature Review

Cerebellopontine Angle Epidermoid Cyst: Surgical Experience of 40 Cases at Bellaria Hospital

Cerebellopontine Angle Epidermoid Cyst: Surgical Experience of 40 Cases at Bellaria Hospital

Comparative Analysis of FIESTA versus Conventional Imaging for Assessment of Cerebellopontine Angle Epidermoid Tumors

Comparative Analysis of FIESTA versus Conventional Imaging for Assessment of Cerebellopontine Angle Epidermoid Tumors

Epidermoid Tumors in the Cerebellopontine Angle Presenting with Trigeminal Neuralgia

The purpose of this study is to evaluate the clinical characteristics and surgical outcome of cerebellopontine angle (CPA) epidermoids presenting with trigeminal neuralgia. Between 1996 and 2004, 10 patients with typical symptoms of trigeminal neuralgia were found to have cerebellopontine angle epidermoids and treated surgically at our hospital. We retrospectively analyzed the clinico-radiological records of the patients. Total resection was done in 6 patients (60%). Surgical removal of tumor and microvascular decompression of the trigeminal nerve were performed simultaneously in one case. One patient died due to postoperative aseptic meningitis. The others showed total relief from pain. During follow-up, no patients experienced recurrence of their trigeminal neuralgia (TN). The clinical features of TN from CPA epidermoids are characterized by symptom onset at a younger age compared to TN from vascular causes. In addition to removal of the tumor, the possibility of vascular compression at the root entry zone of the trigeminal nerve should be kept in mind. If it exists, a microvascular decompression (MVD) should be performed. Recurrence of tumor is rare in both total and subtotal removal cases, but long-term follow-up is required.

Cerebellopontine epidermoid presenting with trigeminal neuralgia for 10 years: a case report.

Trigeminal neuralgia, also called tic douloureux, is a common and potentially disabling pain syndrome, which affects the trigeminal or fifth cranial nerve. The precise pathophysiology of Trigeminal neuralgia remains obscure. The disorder causes extreme, sporadic, sudden burning or shock-like face pain that lasts from few seconds to minutes and can be physically and mentally incapacitating. More than one nerve branch can be affected by the disorder. A 55-year-old female presented with pain over the left side of face for 10 years uncontrolled with carbamazepine. On examination the positive findings were reduced sensation by 25% over the left side of face with House and Brackman grade II facial nerve palsy. The corneal reflex was absent on left side. Magnetic resonance imaging showed left cerebellopontine angle (CPA) mass suggestive of an epidermoid involving the Vth nerve and Gasserian ganglion and extending into the middle cranial fossa. She underwent left suboccipital craniectomy and near total excision of the tumor with decompression of the Vth nerve which was fully engulfed by the tumor. Postoperative the VII nerve palsy increased to grade III and she had 50% loss of sensation over left side. She had no further attacks of pain and hence tapered off the carbamazepine. TN caused by cerebellopontine angle epidermoids is uncommon and should be kept in view in all cases presenting with TN. The aim of surgery for epidermoids is to decompress the cranial nerves and brain stem and not total removal with its attendant morbidity and mortality.

A Case of Cerebellopontine Angle Epidermoid Cyst Presenting as Trigeminal Neuropathy

We present the case of a 35-year-old female who had paraesthesia and numbness on the left side of her face. Initially the ophthalmic division and maxillary divisions on the trigeminal nerve were involved, but later involved the mandibular division as well. On MRI, a cerebellopontine angle (CPA) epidermoid cyst was detected. After 18 months of follow up, her symptoms remain stable and she is being managed conservatively.

Has Management of Epidermoid Tumors of the Cerebellopontine Angle Improved? A Surgical Synopsis of the Past and Present

We compared the surgical outcomes of recent patients with cerebellopontine angle (CPA) epidermoids treated with advanced surgical tools with those of patients treated in earlier series. From November 2000 to June 2004, we treated 12 patients with epidermoid tumors. One patient had a strict CPA lesion. Tumors extended into the prepontine region in seven cases and supratentorially in two. In two cases the CPA was involved bilaterally. All patients but one underwent a lateral suboccipital approach in a semi-sitting position with microsurgical technique. Endoscopic assistance was used in cases with extensions beyond the CPA. In one case, a subtemporal route was used. The mean follow-up was 27 months (range, 8 to 50 months). There were no deaths. Total removal was achieved in 7 of the 10 patients with unilateral CPA epidermoids. Preoperative status improved in eight (80%) patients, particularly the function of cranial nerves (CNs) V and VII. Only two patients had permanent CN deficits. Complete excision with preservation of CN function should be the goals of management of epidermoids of the CPA. In some cases, these goals can be difficult to achieve, even with contemporary surgical equipment. Bilateral and extensive tumors should be removed in staged procedures. The function of CN V and CN VII may recover after decompression, but the outcome of symptoms related to CN VIII is less certain. The endoscope is a reliable tool for assessing the extension of epidermoids, but it cannot be used for tumor removal.

Primary Intracranial Squamous Cell Carcinoma in the Brain Stem with a Cerebellopontine Angle Epidermoid Cyst

Primary intracranial squamous cell carcinoma is extremely rare, with most cases arising from a preexisting benign epidermoid cyst. We report a rare case of primary intracranial squamous cell carcinoma in the brain stem with a cerebellopontine angle (CPA) epidermoid cyst. A 72-year-old female suffered from progressive left hemiparesis, difficulty in swallowing, and right hemifacial numbness. Diffusion-weighted magnetic resonance imaging revealed a high signal intensity (SI) lesion in the CPA region and an intra-axially ring-enhanced cystic mass in the right brain stem with low SI. Whole-body positron emission tomography showed no evidence of metastatic disease. The histological findings revealed a typical epidermoid cyst in the CPA region and a squamous cell carcinoma in the brain stem. We speculate that the squamous cell carcinoma may have been developed due to a chronic inflammatory response by the adjacent epidermoid cyst. The patient underwent a surgical resection and radiotherapy. After 12 months, she had no evidence of recurrence.

Cerebellopontine angle epidermoids presenting with trigeminal neuralgia

We studied the clinical characteristics of cerebellopontine angle (CPA) epidermoids presenting with trigeminal neuralgia (TN). Twenty-four patients were analyzed retrospectively and the literature reviewed with regard to clinical manifestation, imaging features, surgical procedures and prognosis. TN may be the initial symptom of CPA epidermoid, particularly in young patients. Epidermoids are characteristically hypodense nonenhancing lesions on CT scans, while on MRI they exhibit long T1 and T2 relaxation times. Although complete removal is ideal in the surgical management of CPA epidermoid, proximity to cranial nerves and the brain stem may pose technical difficulties in complete resection. In addition to complete resection of the tumour, arterial compression at the root entry zone (REZ) of the trigeminal nerve should be sought, and if found, a microvascular decompression (MVD) should be performed. Cranial nerve dysfunction and aseptic meningitis are the most common operative complications.

Microsurgical Management of Cerebellopontine Angle Epidermoid Tumors: Operative Technique and Results in 152 Cases

Microsurgical Management of Cerebellopontine Angle Epidermoid Tumors: Operative Technique and Results in 152 Cases