Giant intracranial epidermoids: is total removal feasible?

Trigeminal neuralgia secondary to epidermoid cyst and neurovascular conflict: An illustrative case with literature review

Background

Trigeminal neuralgia (TN) is a highly disabling facial pain syndrome, historically known as the suicide disease, in which most cases can be cured with appropriate surgical treatment.

Case Description

We present the case of a 43-year-old male farmer with acute, self-limiting episodes of shock-like pain on the left side of the face that started in June of 2021. He was diagnosed with TN and was treated with carbamazepine. Magnetic resonance imaging was performed, which revealed an epidermoid cyst (EC) at the prepontine cistern with an extension to the left cerebellopontine angle. The neurosurgery department at our institution was consulted, which performed surgical tumor resection and Vth cranial nerve decompression. During the resection, a neurovascular conflict (NVC) was identified at the root entry zone. After the resection around the nerve and its whole tract was completed, a microvascular decompression (MVD) was performed.

Conclusion

TN secondary to EC in association with a NVC is a rare phenomenon, due to the growth pattern of the EC. TN may remit if an appropriate treatment is carried out. In cases of NVC, an MVD is required apart from an appropriate resection to achieve pain relief.

Epidermoid cyst of central nervous system: A case series and review of literature

INTRODUCTION

Epidermoid cysts, originating from ectodermal cell remnants during embryogenesis, are rare, slow-growing tumours commonly found in the cerebellopontine angle, fourth ventricle, and sellar/parasellar regions. This retrospective study explores clinicopathological features, demographics, and radiological details of fifteen central nervous system epidermoid cyst cases over three years.

MATERIALS AND METHODS

Histologically confirmed cases undergoing surgical excision from July 2020 to July 2023 were retrospectively evaluated. Patient age, clinical presentations, radiological features, and histopathological findings were analyzed using descriptive statistics and aligned with the PROCESS criteria.

RESULTS

Fifteen cases, spanning various age groups and clinical presentations, were included. There were four cases each in the posterior fossa and cerebellopontine angle, three in temporal region, two in intraspinal region, and one each in the retromastoid intra-diploic and third intra-ventricular region. Lesions exhibited diverse distribution, gross findings, and microscopic features. Radiological imaging exhibited well-defined hypo-attenuated masses on computed tomography and contributed to the preoperative diagnosis in eight cases. Despite challenges in complete excision due to adherence, 13 cases underwent successful resection. Chemical meningitis, a common postoperative complication, underscores the importance of meticulous surgery.

CONCLUSION

This study highlights clinicopathological characteristics, challenges in surgical management, and postoperative complications of central nervous system epidermoid cysts. Comparative analysis with existing literature emphasizes the uniqueness of epidermoid cysts, differentiating them from craniopharyngiomas and dermoid cysts. Despite the retrospective design, valuable insights are provided, emphasizing the need for prospective studies. Effective management involves complete excision, ensuring long-term remission and emphasizing the distinctive nature of these intriguing intracranial lesions.

Fully neuroendoscopic resection of cerebellopontine angle tumors through a retrosigmoid approach: a retrospective single-center study

The objective of this study is to preliminarily investigate the surgical safety, efficacy, techniques, and clinical value of fully neuroendoscopic surgery for the resection of cerebellopontine angle (CPA) tumors via a retrosigmoid approach. The clinical data of 47 cerebellopontine angle area (CPA) tumors that were treated by full neuroendoscopic surgery from June 2014 to June 2023 were retrospectively analyzed. The efficacy and advantages of the surgical techniques were evaluated based on indicators such as duration of the surgery, neuroendoscopic techniques, intraoperative integrity of nerves and blood vessels, extent of tumor resection, outcomes or postoperative symptoms, and incidence of complications. The 47 cases of cerebellopontine angle tumors include 34 cases of epidermoid cysts, 7 cases of vestibular schwannomas, and 6 cases of meningiomas. All patients underwent fully neuroendoscopic surgery. Twenty tumors were removed using the one-surgeon two-hands technique, and 27 tumors were removed using the two-surgeons four-hands technique. The anatomical integrity of the affected cranial nerves was preserved in all 47 cases. None of the patients suffered a postoperative hemorrhage, cerebrospinal fluid leak, and aseptic or septic meningitis, or died. The rate of total tumor resection was 72.3% (34/47), and the symptom improvement rate was 89.4% (42/47). All patients were followed up for 2 to 12 months, and none died nor showed any signs of tumor recurrence. By analyzing 47 fully neuroendoscopic resections of CPA tumors using the posterior sigmoid sinus approach in our center, we believe that such method allows complete, safe, and effective resection of CPA tumors and is thereby worthy of clinical promotion.

Giant epidermoid cyst penetrating the skull: a case report and literature review

Intracranial epidermoid cyst is a rare pseudotumor of the nervous system, accounting for 0.2%-1.8% of all intracranial tumors. It is usually located in the cerebellopontine Angle or parasellar area, with insipid onset, slow growth and usually less than 2 cm in diameter. Giant epidermoid cysts that invade the bone have rarely been reported in the literature. Herein, we report a case of giant ECs extradural to the parietal bone, penetrating the skull and continuing to expand outward. In addition, a systematic search of four authoritative databases was conducted to collect the relevant reports of giant epidermoid cyst with diameter > 5cm for the first time, and to discuss the clinical and radiographic features of patients with giant epidermoid cyst and the influence of treatment options.

The Endoscopic Resection of Sellar and Suprasellar Epidermoid Cyst in a Pediatric Patient: A Case Report and Review of the Literature

Epidermoid cysts are benign congenital tumors that originate from the ectodermal tissue. The sellar/suprasellar region is an infrequent location for epidermoid cysts and such cases are rarely reported in pediatric patients, as these become symptomatic only when they reach 30 years of age. Surgical intervention is considered the ideal treatment option in patients with suprasellar epidermoid cysts, either via open or endonasal approach. We discuss a case of a 12-year-old male who presented with left visual impairment and was treated with successful resection through an endoscopic endonasal approach (EEA). We also engage in a literature review of the use of EEA in the management of sellar/suprasellar epidermoid cysts in the pediatric age group.

Neurosurgical Education Using Cadaver-Free Brain Models and Augmented Reality: First Experiences from a Hands-On Simulation Course for Medical Students

Background and Objectives: Neurosurgery has been underrepresented in the medical school curriculum. Advances in augmented reality and 3D printing have opened the way for early practical training through simulations. We assessed the usability of the UpSurgeOn simulation-based training model and report first experiences from a hands-on neurosurgery course for medical students. Materials and Methods: We organized a two-day microneurosurgery simulation course tailored to medical students. On day one, three neurosurgeons demonstrated anatomical explorations with the help of life-like physical simulators (BrainBox, UpSurgeOn). The surgical field was projected onto large high-definition screens by a robotic-assisted exoscope (RoboticScope, BHS Technologies). On day two, the students were equipped with microsurgical instruments to explore the surgical anatomy of the pterional, temporal and endoscopic retrosigmoid approaches. With the help of the RoboticScope, they simulated five clipping procedures using the Aneurysm BrainBox. All medical students filled out a digital Likert-scale-based questionnaire to evaluate their experiences. Results: Sixteen medical students participated in the course. No medical students had previous experience with UpSurgeOn. All participants agreed that the app helped develop anatomical orientation. They unanimously agreed that this model should be part of residency training. Fourteen out of sixteen students felt that the course solidified their decision to pursue neurosurgery. The same fourteen students rated their learning experience as totally positive, and the remaining two rated it as rather positive. Conclusions: The UpSurgeOn educational app and cadaver-free models were perceived as usable and effective tools for the hands-on neuroanatomy and neurosurgery teaching of medical students. Comparative studies may help measure the long-term benefits of UpSurgeOn-assisted teaching over conventional resources.

Surgical Management of Temporal Lobe Epilepsy Secondary to Epidermoid Cysts: A Case Report With Review of the Literature

Epidermoid cysts represent roughly 1% of all intracranial tumors. They are frequently located in the cerebellopontine angle but rarely extend to the supratentorial brain. Epilepsy is an extremely uncommon manifestation of this neoplasm. We suggest the surgical management of a 35-year-old male who presented with a six-month history of intractable temporal lobe epilepsy. His seizures were characterized by a focal onset in the form of déjà vu experiences, followed by a secondarily generalized tonic-clonic seizure. Imaging revealed a heterogeneous cystic mass in the right cerebellopontine angle, extending supratentorially causing a mass effect on the mesial temporal region. Gross total resection was achieved through a combined subtemporal-retrosigmoid approach. Histopathology revealed an epidermoid cyst. The patient was entirely seizure-free at the three-month follow-up. Epidermoid cysts may present with epileptic seizures. Seizure freedom can be achieved with surgical management in most cases. The patient's symptoms, imaging findings, and epileptogenic focus must be considered to select the appropriate surgical strategy.

Intracranial epidermoid cysts: benign entities with malignant behavior: experience with 36 cases

Intracranial epidermoid cysts are benign slow-growing ectodermal inclusions that account for less than 1% of all intracranial tumors. We retrospectively reviewed 36 such cases to evaluate the demographic characteristics, clinical manifestations, anatomical distribution, surgical management, and treatment outcome of these tumors. Additionally, we sought to identify the relationship between median or paramedian cistern tumor localization and clinical parameters, such as recurrence risk, hospitalization duration, and postoperative complication rates. The most frequently observed neurological symptoms were transient headaches (77.8%), dizziness (36.1%), CN VII palsy (19.4%), CN VIII hearing difficulty (19.4%) and cerebellar signs (19.4%). The most common surgical approaches included retrosigmoid (36.1%), subfrontal (19.4%) and telovelar (19.4%) approaches; gross total resection was feasible in 83.3% of cases. The postoperative complication rate was 38.9%. Tumors were more frequently found in the paramedian cisterns (47.2%), followed by the median line cisterns (41.6%). Multivariate analysis revealed that postoperative hydrocephalus and age < 40 years were prognostic factors for tumor recurrence. Median-like tumor location was a risk factor for the presence of symptomatic hydrocephalus both preoperatively and postoperatively, increasing the likelihood of protracted hospitalization (> 10 days). Despite their benign histopathological nature, these tumors have an important clinical resonance, with a high rate of postoperative complications and a degree of recurrence amplified by younger age and hydrocephalus.

Endoscopically operated 15 ventral skull-base dermoid and epidermoid cysts: Outcomes of a case series and technical note

BACKGROUND

Epidermoid and dermoid tumors in the sellar region are rare. These cystic lesions are a surgical challenge, as the thin capsule adheres firmly to nearby structures. A case series of 15 patients is presented.

METHODS

The patients were operated on in our clinic between April 2009 and November 2021. The endoscopic transnasal approach (ETA) was used. Lesions were located in the ventral skull base. In addition, the literature was reviewed to compare clinical features and outcomes of ventral skull-base epidermoid/dermoid tumors operated on via ETA.

RESULTS

In our series, removal of cystic contents and tumor capsule (gross total resection: GTR) was achieved in 3 patients (20%). GTR was not possible for the others, because of adhesions to vital structures. Near total resection (NTR) was achieved in 11 patients (73.4%), and subtotal resection (STR) in 1 (6.6%). At a mean follow-up of 55±26.27 months, there were no cases of recurrence requiring surgery.

CONCLUSION

Our series demonstrates that ETA is suitable for resection of epidermoid and dermoid cysts in the ventral skull base. GTR cannot always be the absolute clinical aim, because of inherent risks. In patients with expected long-term survival, the aggressiveness of surgery should be weighed on an individual risk/benefit basis.

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.

Giant cerebral cavernous malformations: redefinition based on surgical outcomes and systematic review of the literature

OBJECTIVE

Giant cerebral cavernous malformations (GCCMs) are rare vascular malformations. Unlike for tumors and aneurysms, there is no clear definition of a "giant" cavernous malformation (CM). As a result of variable definitions, working descriptions and outcome data of patients with GCCM are unclear. A new definition of GCCM related to surgical outcomes is needed.

METHODS

An institutional database was searched for all patients who underwent resection of CMs > 1 cm in diameter. Patient information, surgical technique, and clinical and radiographic outcomes were assessed. A systematic review was performed to augment an earlier published review.

RESULTS

In the authors' institutional cohort of 183 patients with a large CM, 179 with preoperative and postoperative modified Rankin Scale (mRS) scores were analyzed. A maximum CM diameter of ≥ 3 cm was associated with greater risk of severe postoperative decline (≥ 2-point increase in mRS score). After adjustment for age and deep versus superficial location, size ≥ 3 cm was strongly predictive of severe postoperative decline (OR 4.5, 95% CI 1.2-16.9). A model with CM size and deep versus superficial location was developed to predict severe postoperative decline (area under the receiver operating characteristic curve 0.79). Thirteen more patients with GCCMs have been reported in the literature since the most recent systematic review, including some patients who were treated earlier and not discussed in the previous review.

CONCLUSIONS

The authors propose that cerebral CMs with a diameter ≥ 3 cm be defined as GCCMs on the basis of the inflection point for functional and neurological outcomes. This definition is in line with the definitions for other giant lesions. It is less exclusive than earlier definitions but captures the rarity of these lesions (approximately 1% incidence) and variation in outcomes. GCCMs remain operable with potentially favorable outcomes. The term "giant" is not meant to deter or contraindicate surgery.

Surgical Presets of Ruptured Dermoid Cyst Resection: 2-Dimensional Operative Video

Intracranial dermoid cyst is a benign expansive lesion typically affecting children and young adults. They become symptomatic by progressive enlargement of the cyst and spilling of its content. In such cases, recurrent aseptic meningitis is observed. When located in the suprasellar area, optic pathways are usually displaced and compressed, and visual symptoms are common, as well as seizures. The tumor capsule can be thick and very adherent to the anterior cerebral arteries and the small arterial perforators. Radical surgical resection, including the capsule, is the current mainstay of treatment.1-5 The cranio-orbital approach is considered as an excellent surgical access option. Vascular adhesions are associated with a considerable surgical risk to the circle of Willis and its small branches. Residual cyst or perioperative spilling of its content produces severe aseptic meningitis and vasospasm associated with postoperative complications and long-term recurrences.4 This article demonstrates the details of the surgical management of a ruptured suprasellar dermoid cyst in a 22-year-old man. The patient consented to the procedure and publication of images. Image at 2:23 reprinted with permission from Al-Mefty O, Operative Atlas of Meningiomas, Vol 1, ©LWW, 1998. Illustration at 2:47 reprinted from Surgical Neurology, 50(6), Arnautovic et al, "A combined microsurgical skull-base and endovascular approach to giant and large paraclinoid aneurysms," p 17, ©1998, with permission from Elsevier.

Long-term surgical oncological and functional outcome of large spetroclival and cerebellopontine angle epidermoid cysts: a multicenter study

Cranial nerve (CN) disorders are the foremost symptoms in cerebellopontine angle (CPA) and petroclival area (PCA) epidermoid cysts (EC).The aim of this work was to  assess the long-term surgical results on CN function and tumor control in these patients EC. We performed a retrospective cohort study about 56 consecutive patients operated on for a CPA or PCA EC between January 2001 and July 2019 in six participating French cranial base referral centers. Sixteen patients (29%) presented a PCA EC and 40 a CPA EC (71%). The median clinical and radiological follow-up was 46 months (range 0-409). Preoperative CN disorders were present in 84% of patients (n = 47), 72% of them experienced CN deficits improvement at the last follow-up consultation (n = 34): 60% of cochlear and vestibular deficits (n = 9/15 in both groups), 67% of trigeminal neuralgia (n = 10/15), 53% of trigeminal hypoesthesia (n = 8/15), 44% of lower cranial nerve disorders (n = 4/9), 38% of facial nerve deficits (n = 5/8) and 43% of oculomotor deficits (n = 3/7) improved or were cured after surgery. New postoperative CN deficits occurred in 48% of patients (n = 27). Most of them resolved at the last follow-up, except for cochlear deficits which improved in only 14% of cases (n = 1/7). Twenty-six patients (46%) showed evidence of tumor progression after a median duration of 63 months (range 7-210). The extent of resection, tumor location, and tumor size was not associated with the occurrence of new postoperative CN deficit or tumor progression. A functional nerve-sparing resection of posterior fossa EC is an effective strategy to optimize the results on preexisting CN deficits and reduce the risk of permanent de novo deficits.

Giant Pediatric Supratentorial Tumor: Clinical Feature and Surgical Strategy

PURPOSE

To analyze the clinical character of giant pediatric supratentorial tumor (GPST) and explore prognostic factors.

MATERIALS AND METHODS

We analyzed the clinical data comprising of 35 cases of GPST from a single center between January 2015 and December 2020. The tumor volume was measured by 3D slicer software based on preoperative magnetic resonance imaging (MRI). Glasgow Outcome Scale (GOS) was used to evaluate the short-term prognosis.

RESULT

The tumor volume varied from 27.3 to 632.8 ml (mean volume 129.8 ml/ median volume 82.8 ml). Postoperative histopathological types include ependymoma, pilocytic astrocytoma, choroid plexus papilloma (CPP), craniopharyngioma, primitive neuroectoderm tumor (PNET), choroid plexus carcinoma (CPC), immature teratoma, atypical teratoid rhabdoid tumor (AT/RT), anaplastic astrocytoma, and gangliocytoma. Tumors in children younger than 3 years and tumors located at the hemispheres appeared to be larger than their respective counterparts, though no statistical significance was found. A patient with giant immature teratoma died during the operation because of excessive bleeding. Postoperative complications include cerebrospinal fluid subgaleal collection/effusion, infection, neurological deficits, and seizures. The mean GOS score of patients with GPST in 6 months is 3.43 ± 1.12, and 83% of patients (29/35) showed improvement. Favorable GPST characteristics to indicated better GOS included small tumor (≤100 ml) (p = 0.029), low-grade (WHO I-II) (p = 0.001), and gross total resection (GTR) (p = 0.015). WHO grade was highly correlated with GOS score (correlation coefficient = -0.625, p < 0.001). GTR and tumor volume were also correlated (correlation coefficient = -0.428, p = 0.010).

CONCLUSION

The prognosis of GPST is highly correlated with the histopathological type. Smaller tumors are more likely to achieve GTR and might lead to a higher GOS score. Early diagnosis and GTR of the tumor are important for GPST management.

Dysfunctions and anatomical relationships of cranial nerves in epidermoids of the cerebellopontine angle

OBJECTIVE

To evaluate the correlation of neurological symptoms with anatomical relationships of cranial nerves, lesions and vessels in patients with epidermoids of the cerebellopontine angle.

MATERIAL AND METHODS

We analyzed neurological symptoms, magnetic resonance data, intraoperative findings and postoperative functional outcomes in 25 patients (14 females and 11 males aged 22-77 years) with epidermoids of the cerebellopontine angle.

RESULTS

Cranial nerve dysfunctions were noted in 15 patients. Involvement of cochlear (n=9) and trigeminal (9 cases including 4 ones with sensory impairment and 5 patients with neuralgia) nerves was the most common. There were 10 patients with ataxia, hemiparesis and seizures without cranial nerve dysfunction. In 15 patients, epidermoids spread to supratentorial space and contralateral cerebellopontine angle. Lesion-induced brainstem compression was found in 22 cases. Cranial nerves and cerebellar arteries were partially or completely enclosed by lesion in all cases. Severe compression and dislocation of the nerve root entry/exit zone were found in all cases. One patient with trigeminal neuralgia had vascular compression of trigeminal nerve caused by superior cerebellar artery. Total resection was achieved in 16 patients. Small capsule remnants were left on vessels, nerves or brainstem in 9 patients. Postoperative complete or partial restoration of cranial nerve functions was noted in 11 cases. Deterioration of preoperative neurological deficit in 4 patients and postoperative neurological symptoms de novo in 3 patients were temporary.

CONCLUSION

Cranial nerve dysfunctions are caused by compression of the nerve root entry/exit zones by epidermoids of the cerebellopontine angle. Surgical intervention is effective in alleviating symptoms of cranial neuropathy and brainstem compression. Vascular decompression should be performed in patients with trigeminal neuralgia.

A Good Aesthetic Outcome After Gross Total Tumor Resection in Combination With the Skull Reconstruction on Giant Epidermal Cyst Involving Both Intracranial and Extracranial Tissues

ABSTRACT

Epidermal or epidermoid cysts are 1 of the most frequent benign masses, they rarely grow to a huge size, and only a few cases have been reported. We report a rare case of a 52-year-old man with giant neoplasm growing invasively in the frontal region, including both intracranial and extracranial extensions, and caused extensive brain deformation and skull lesions. It is worth noting that the patient did not present any significant neurological symptoms and deficits for more than 40 years on admission. A combination of gross total tumor resection and cranioplasty was performed. The patient was satisfied with the results of the surgery, and no evidence of recurrence or complications were found in the 2 years follow-up. The authors reported the case not only to propose the first-stage aesthetic treatment option for this unusual mass on the scalp but also hinted at the vigilance and importance of systematic monitoring of the small skull mass for avoiding the potential risk of tumor progression, malignant transformation, operative trauma, and financial burden.

Case report: Scattered intraventricular lesions on MRI following epidermoid cyst resection

Local recurrence after epidermoid cyst surgery is a frequently reported complication, but intraventricular spread after surgery has not yet been described in literature. We present the case of a 61-year-old male patient with steadily progressive headaches after surgical excision of an epidermoid cyst in the right cerebellopontine angle about two months ago. The MRI showed multiple intraventricular FLAIR-hyperintensities with diffusion restriction, suggestive of scattered remnants of the epidermoid cyst. We recommend early postoperative MRI-scans after cranial epidermoid surgery, which should be carefully inspected not only for local remnants but also rare complications like intraventricular spread.

Long-term surgical outcomes of intracranial epidermoid tumors: impact of extent of resection on recurrence and functional outcomes in 63 patients

OBJECTIVE

The authors' objective was to reevaluate the role of microsurgery for epidermoid tumors by examining the associations between extent of resection (EOR), tumor control, and clinical outcomes.

METHODS

This was a retrospective study of patients with microsurgically treated intracranial epidermoid tumors. The recurrence-free and intervention-free rates were calculated using the Kaplan-Meier method. EOR was graded as gross-total resection (GTR) (total resection without residual on MRI), near-total resection (NTR) (a cyst lining was left in place), subtotal resection (STR) (> 90% resection), and partial resection (PR) (any other suboptimal resection) and used to stratify outcomes.

RESULTS

Sixty-three patients with mean clinical and radiological follow-up periods of 87.3 and 81.8 months, respectively, were included. Sixteen patients underwent second resections, and 5 underwent third resections. The rates of GTR/NTR, STR, and PR were 43%, 35%, and 22%, respectively, for the initial resections; 44%, 13%, and 44% for the second resections; and 40%, 0%, and 60% for the third resections (p < 0.001). The 5- and 10-year cumulative recurrence-free rates after initial resection were 64% and 32%, respectively. When stratified according to EOR, the 10-year recurrence-free rate after GTR/NTR was marginally better than that after STR (61% vs 35%, p = 0.130) and significantly better than that after PR (61% vs 0%, p < 0.001). The recurrence-free rates after initial microsurgery were marginally better than those after second surgery (p = 0.102) and third surgery (p = 0.065). The 5- and 10-year cumulative intervention-free rates after initial resection were 91% and 58%, respectively. When stratified according to EOR, the 10-year intervention-free rate after GTR/NTR was significantly better than that after STR (100% vs 51%, p = 0.022) and PR (100% vs 27%, p < 0.001). The 5-year intervention-free rate after initial surgery was marginally better than that after second surgery (52%, p = 0.088) and significantly better than that after third surgery (0%, p = 0.004). After initial, second, and third resections, permanent neurological complications were observed in 6 (10%), 1 (6%), and 1 (20%) patients, respectively. At the last follow-up visit, 82%, 23%, and 7% of patients were free from radiological recurrence after GTR/NTR, STR, and PR as the initial surgical procedure, respectively.

CONCLUSIONS

GTR/NTR seems to contribute to better disease control without significantly impairing functional status. Initial resection offers the best chance to achieve better EOR, leading to better disease control.

Endoscopic Keyhole Approach for Intracranial Epidermoid

Objective  In contemporary neurosurgical practice, keyhole endoscopic approach has established its role in various neurosurgical pathologies. Intracranial epidermoid is an ideal pathology for endoscopic keyhole approach as epidermoid is well encapsulated, extra-axial, avascular, and easily suckable. The objective of this study is to share our experience of endoscopic keyhole approach for intracranial epidermoids at various locations as a new minimally invasive neurosurgical approach to deal with these lesions. Materials and Methods  We conducted a retrospective study on 26 patients who underwent keyhole pure endoscopic excision of intracranial epidermoid between July 2015 and December 2019. Patient's demographics, clinical features, radiological imaging, and postoperative complications were noted. Follow-up outcome of preoperative symptoms and postoperative complications were also analyzed. Results  The mean age of the study population was 30.5 years with a mean follow-up of 30 months. The common presenting features were headache, hearing loss, and trigeminal neuralgic pain. Gross total resection was achieved in 73.1% cases, while near total resection and subtotal resection were achieved in 19.2 and 7.7% cases, respectively. In the follow-up, maximal improvement was seen in trigeminal neuralgic pain (83%) and headache (66.7%). Major postoperative complications were facial nerve paresis, lower cranial nerve paresis, and transient facial hypoesthesia, most of which improved over time. None of the patients required resurgery till date. Statistical Analysis  Patients' data were analyzed using SPSS software version 23 (Statistical Package for Social Sciences, IBM, Chicago, United States). Conclusion  This study demonstrates that with careful patient selection, endoscopic keyhole excision of epidermoid is a good alternative to conventional microsurgical excision with comparable surgical and functional outcomes.

The role of apparent diffusion coefficient as a predictive factor for tumor recurrence in patients with cerebellopontine angle epidermoid tumor

Intracranial epidermoid tumors are slowly growing benign tumors, but due to adjacent critical neurovascular structures, surgical resection is challenging, with the risk of recurrence. The apparent diffusion coefficient (ADC) has been used to evaluate the characteristics of brain tumors, but its utility for intracranial epidermoid tumors has not been specifically explored. This study analyzed the utility of preoperative ADC values in predicting tumor recurrence for patients with intracranial epidermoid tumors. Between 2008 and 2019, 21 patients underwent surgery for cerebellopontine angle (CPA) epidermoid tumor, and their preoperative ADC data were analyzed. The patients were divided into two groups: the recurrence group, defined by regrowth of the remnant tumor or newly developed mass after gross total resection on magnetic resonance imaging (MRI); and the stable group, defined by the absence of growth or evidence of tumor on MRI. Receiver operating characteristic (ROC) analysis was used to obtain the ADC cutoff values for predicting tumor recurrence. The prognostic value of the ADC was assessed using Kaplan-Meier curves. The minimum ADC values were significantly lower in the recurrence group than in the stable tumor group (P = 0.020). ROC analysis showed that a minimum ADC value lower than 804.5 × 10^-6 mm²/s could be used to predict higher recurrence risk of CPA epidermoid tumors. Non-total resection and mean and minimum ADC values lower than the respective cutoffs were negative predictors of recurrence-free survival. Minimum ADC values could be useful in predicting the recurrence of CPA epidermoid tumors.

Importance of appropriate surgical approach selection for radical resection of cerebellopontine angle epidermoid cysts with preservation of cranial nerve functions: our experience of 54 cases

BACKGROUND

Although many reports state that only the lateral suboccipital retrosigmoid approach (LSO) should be used for removal of cerebellopontine angle (CPA) epidermoid cysts, it is preferable to use various surgical approaches as appropriate for each patient, for radical resection with an optimal operative field under direct visualization, and for the preservation of cranial nerve (CN) functions. In the present study, we hence focused on the importance of surgical approach selection for removal of CPA epidermoid cysts and analyzed the results of CPA epidermoid cysts after surgery in our series.

METHODS

Fifty-four patients who underwent surgery for CPA epidermoid cysts were retrospectively analyzed, regarding their surgical approaches, removal rates, preservation rates of CN function 1 year after surgery, and recurrence. Surgical approaches were selected for patients according to the size and extension of the tumor.

RESULTS

Surgical approaches consisted of LSO (20 cases), anterior transpetrosal approach (ATP; 3 cases), combined transpetrosal approach (27 cases), and ATP + LSO (4 cases). Mean tumor content removal and capsule removal rates were 97.4% and 78.3%, respectively. Preservation rates of facial nerve function and useful hearing were 94.4% and 90.7%, respectively. The mean postoperative follow-up time was 62.8 months, and there were two cases of recurrence requiring reoperation about 10 years after surgery.

CONCLUSIONS

For CPA epidermoid cyst surgeries, selection of the appropriate surgical approach for each patient and radical resection with an optimal operative field under direct visualization enable tumor removal without the need for reoperation for a long time, with preservation of CN functions.

Radical Resection of a Giant Epidermoid Tumor Associated With Miniature Chordoma Utilizing a Combined Endoscopic-Microscopic Technique: 2-Dimensional Operative Video

Epidermoid tumors arise from misplaced squamous epithelium and enlarge through the accumulation of desquamated cell debris.1 Notwithstanding the prevailing conservative attitudes to minimize morbidity, optimal treatment consists of total removal of the capsule2,3; therefore, giant and multicompartmental tumors are particularly challenging. The utilization of simultaneous endoscopic microscopic techniques by tandem endoscopic and microscopic dissection to overcome the shortcomings of both modalities, markedly enhances the ability of radical removal,4 thus eliminating or at least long-delaying inevitable recurrences with subsequent accumulated morbidity. The transmastoid approach by skeletonizing and reflexing the transverse-sigmoid sinus offers wide exposure of the cerebellopontine angle avoiding cerebellar retraction and allowing 4-hands dissection.5 The patient is a 17-yr-old male with a giant epidermoid tumor in the cerebellopontine angle, extending through the incisura. The patient underwent surgical resection with maximum pursuit of the epithelial capsule. After removing the epidermoid tumor, a miniature intra and extradural midclival tumor was encountered and removed with a proven pathology of chordoma. Patient did well postoperatively with relief of his hemifacial spasms. Patient consented for surgery and photograph publication. Image at 1:23, ©1997, O. Al-Mefty, used with permission. All rights reserved.

Endoscopic-Assisted Keyhole Resection of a Recurrent Epidermoid Tumor: 2-Dimensional Operative Video

Epidermoid tumors are benign lesions. Surgical resection is the only treatment option available for these lesions.1 The surgical approach should be tailored to the clinical and anatomic findings to achieve radical resection, preferably total removal of the content and the capsule to prevent recurrences.2 Total resection is frequently possible in de novo lesions using tailored skull base approaches and their combination as well as modern microsurgical techniques, including the endoscope-assisted tools.2,3 Giant recurrent tumors, however, are not amenable for total resection. Hence, the severe adhesions will lead to a higher morbidity as the epidermoid capsule becomes thicker and more fibrous after prior resections attempts.2,4 The extent of the resection should still be safely extended as much as possible to delay the interval between surgeries. Endoscopic techniques are of great help in achieving such results through a keyhole approach when conservative surgery is decided.3 We present the case of a 69-yr-old male with a past medical history of coronary heart disease, hypertension, hypothyroidism, and recurrent giant epidermoid cyst in the left cerebellopontine angle, with significant compression of the brainstem and extended into Meckel's cave, internal auditory canal, and jugular fossa. He underwent resection in 1983, 2004, and 2012. He presented with worsening gait, and multiple cranial nerves deficits. A minimally invasive approach through a keyhole craniotomy was performed given the age, comorbidity, and multirecurrent nature of his lesion. The patient consented to the intervention and publication of his image. He had a satisfying evacuation of his cyst content with transient facial and lower cranial nerve postoperative worsening.

Analysis of Giant Intraventricular and Extraventricular Epidermoids, Defining Risk Factors for Recurrence, an Institutional Experience

Background:

Multicompartmental intraventricular epidermoids behave differently from multicompartmental extraventricular lesions and localized lesions during its management. Few studies are available which have analyzed risk factors separately in these groups of cases for recurrence of these lesions and time to recur.

Materials and Methods:

In this retrospective observational study, 72 cases of intracranial epidermoid were treated over a span of 7 years. Cases were categorized into three groups. Group 1 comprised 15% (11/72) of cases with intraventricular multicompartmental, Group 2 with 22% (16/72) extraventricular giant tumors with multicompartmental involvement and size >4.5 cm, and Group 3 comprised 63% (45/72) of patients with lesions <4.5 cm and localized. Data pertaining to demography, clinical and radiological features, surgery performed, postoperative complication, histology, and follow-up were obtained from medical records available in the institute.

Results:

The average duration to treat was 1.86 ± 0.52 (standard deviation [SD]) years, with headache as a major complaint in all the groups. Combined endoscope-assisted microsurgery was performed in 38.8% (28/72), microsurgery in 54.1% (39/72), and endoscopic excision in 6.9% (5/72) of cases. Tumor calcification was found in 23.6% (17/72) and preoperative capsular enhancement was seen in 19.4% (14/72) which persisted in 79% (11/14) of cases postoperatively on subsequent follow-up suggesting recurrence. On stepwise logistic regression analysis, preoperative capsular enhancement was a strong predictor of recurrence of tumor (P = 0.001). The average follow-up was 46 ± 14.92 (SD) months in Group 1, 52.34 ± 11.45 (SD) months in Group 2, and 63.36 ± 18.42 (SD) months in Group 3.

Conclusion:

Although the intracranial epidermoid is known to recur after long interval, tumor with specific characteristics can recur in short span of 5–6 years. Tumor characteristics such as preoperative capsular enhancement, multicompartmental distribution in vertebrobasilar territory, large size, and presence of calcification are strong predictors for recurrence. Performing endoscope-assisted microsurgery can decrease the postoperative morbidities but does not reduce the recurrence risk.

Microsurgery for intradural epidermoid cyst at cauda equina level in a 9-year-old child: A case report

Introduction and importance

Epidermoid cysts are rare benign tumors. Here, we present a case of spontaneous intradural epidermoid cyst at cauda equina level in a 9-year-old patient, which we believed the first case to be reported in Vietnam.

Case presentation

A 9-year-old boy presented with 4 months of spontaneous left lower extremity muscle weakness and paresthesia. The MRI images suggested the diagnosis of intradural epidermoid cyst at cauda equina level. The patient underwent L5–S1 laminectomy and durotomy for tumor resection. The histology confirmed the diagnosis of epidermoid cyst. Post-operative images demonstrated total cyst removal.

Clinical discussion

The epidermiology, presentation and diagnosis and strategy of treatments as well as their outcomes were discussed.

Conclusion

Diagnosis of spinal epidermoid cyst is often delayed for its obscure presentation. Microsurgical dissection along with intra-operative mobile C-Arms enable total tumor resection while preserving spinal stability and neurological function. Follow-up with post-operative magnetic resonance imaging and tumor marker are helpful.

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Diagnosis of spinal epidermoid cyst is often delayed for its obscure presentation.

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Microsurgical dissection and mobile C-Arm enables total tumor resection while preserving stability and neurological function

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Magnetic resonance imaging and tumor marker are helpful in follow-up.

Fully Endoscopic Resection of an Epidermoid Cyst of the Cerebellopontine Angle: Bilateral Resection via a Unilateral Approach

BACKGROUND AND IMPORTANCE

Epidermoid cysts are rare, benign intracranial neoplasms that typically arise at the cerebellopontine angle (CPA) and can be extensive lesions that intricately involve many critical neurovascular structures. We describe the case of a patient who presents with the classic picture of CPA epidermoid cyst and describe the value of the 4K endoscope for resection, which is illustrated in our accompanying surgical video.

CLINICAL PRESENTATION

The patient presents with headache, nausea, and vomiting accompanied by dizziness and balance issues. Radiographic imaging demonstrated a large lesion highly consistent with epidermoid cyst which involved the left CPA, encircled the basilar artery, and extended to the opposite side. Surgery was planned with a small left-sided retrosigmoid craniotomy with use of a 2-dimensional 4K endoscope to aid in resection, particularly of the contralateral side. This approach was successful with gross total resection apparent at 14-mo follow-up.

CONCLUSION

We describe the use of a fully endoscopic technique from a unilateral approach for resection of a lesion that extended in the CPA bilaterally. Additionally, we highlight the relevant neuroanatomical and neurovascular structures in this highly critical intracranial region which is well-visualized through endoscopy in the associated surgical video.

A Case of Trigeminal Neuralgia Due to Cerebellopontine Epidermoid Cyst: Discrepancy between Intraoperative and Radiological Findings of Constructive Interference in Steady State (CISS)

Trigeminal neuralgia (TN) is characterized by lightning pain paroxysms in the somatosensory distribution of the trigeminal nerve accompanied by hypersensitivity to non-nociceptive stimuli. Epidermoid cysts sometimes cause TN. To plan the surgery, constructive interference in steady state (CISS) image is useful for understanding the tumor’s location, extent, and relationship against the cranial nerves, and epidermoid cysts are shown as hypointense compared to cerebrospinal fluid (CSF). However, we herein describe a case with TN due to epidermoid cysts, whose intraoperative findings are different from the preoperative and postoperative CISS image. A 49-year-old woman has suffered from TN. CISS images revealed the prolonged trigeminal nerve and the hypointense tumor compared to the CSF at the right cerebellopontine angle. CISS image suggested that the tumor would surround the trigeminal nerve, reach into the Meckel cavity, and offend and compress the trigeminal nerve’s root entry zone (REZ). However, contrary to our expectation, the trigeminal nerve was not surrounded by the tumor. Neuroendoscope revealed that the tumor compressed the REZ, but the tumor was not present in the Meckel cavity. We performed partial tumor removal around the trigeminal nerve, and her symptoms improved. However, the postoperative CISS image was similar to the preoperative one, and so we could not evaluate the remaining tumor. The pathological diagnosis was epidermoid cysts. Intraoperative findings are sometimes different from the pre- and postoperative CISS images, making it difficult to follow up the remaining part of the epidermoid cyst.

Extent of resection of epidermoid tumors and risk of recurrence: case report and meta-analysis

OBJECTIVE

Intracranial epidermoid tumors are slow-growing, histologically benign tumors of epithelial cellular origin that can be symptomatic because of their size and mass effect. Neurosurgical resection, while the treatment of choice, can be quite challenging due to locations where these lesions commonly occur and their association with critical neurovascular structures. As such, subtotal resection (STR) rather than gross-total resection (GTR) can often be performed, rendering residual and recurrent tumor potentially problematic. The authors present a case of a 28-year-old man who underwent STR followed by aggressive repeat resection for regrowth, and they report the results of the largest meta-analysis to date of epidermoid tumors to compare recurrence rates for STR and GTR.

METHODS

The authors conducted a systemic review of PubMed, Web of Science, and the Cochrane Collaboration following the PRISMA guidelines. They then conducted a proportional meta-analysis to compare the pooled recurrence rates between STR and GTR in the included studies. The authors developed fixed- and mixed-effect models to estimate the pooled proportions of recurrence among patients undergoing STR or GTR. They also investigated the relationship between recurrence rate and follow-up time in the previous studies using linear regression and natural cubic spline models.

RESULTS

Overall, 27 studies with 691 patients met the inclusion criteria; of these, 293 (42%) underwent STR and 398 (58%) received GTR. The average recurrence rate for all procedures was 11%. The proportional meta-analysis showed that the pooled recurrence rate after STR (21%) was 7 times greater than the rate after GTR (3%). The average recurrence rate for studies with longer follow-up durations (≥ 4.4 years) (17.4%) was significantly higher than the average recurrence rate for studies with shorter follow-up durations (< 4.4 years) (5.7%). The cutoff point of 4.4 years was selected based on the significant relationship between the recurrence rate of both STR and GTR and follow-up durations in the included studies (p = 0.008).

CONCLUSIONS

STR is associated with a significantly higher rate of epidermoid tumor recurrence compared to GTR. Attempts at GTR should be made during the initial surgery with efforts to optimize success. Surgical expertise, as well as the use of adjuncts, such as intraoperative MRI and neuromonitoring, may increase the likelihood of completing a safe GTR and decreasing the long-term risk of recurrence. The most common surgical complications were transient cranial nerve palsies, occurring equally in STR and GTR cases when reported. In all postoperative epidermoid tumor cases, but particularly following STR, close follow-up with serial MRI, even years after surgery, is recommended.

Microsurgical Resection of the Epidermoid Tumor in the Cerebellopontine Angle

In this video, we demonstrate epidermoid tumor microsurgical resection of the cerebellopontine angle (CPA) performed by the senior author (K.I.A.). Epidermoid tumors arise from ectoderm trapped within/displaced into the central nervous system. They show predilection for CPA Angle (up to 40%), 4th ventricle, suprasellar region, and spinal cord. 1 They are the 3rd most common CPA tumor, comprising approximately 7% of CPA pathology. CPA lesions can produce 5th and 7-12th cranial nerve neuropathies. 2 3 4 Recurrent episodes of aseptic meningitis caused by cyst content rupture may occur. Symptoms include fever, meningeal irritation, and hydrocephalus. A 26-year-old female presented with headaches. Head magnetic resonance imaging (MRI) revealed right CPA tumor with brain stem compression ( Fig. 1 , A - C ). There was evidence of restricted diffusion in diffusion-weighted imaging, typical of epidermoid tumor. Surgery was performed in prone position with head turned 25 degrees to the ipsilateral side using retrosigmoid craniotomy. 5 Tumor was ventral to the 7th and 8th cranial nerve complexes, between the 5th nerve as well as toward the brainstem. The surgical plan was gross total resection with tumor capsule resection to prevent recurrence. 6 (Small residuals can be left behind when capsule is adherent to critical structures.) Tumor was adherent to brain stem perforators which were preserved using meticulous dissection. Cranial nerves and vascular structures were also left intact. We irrigated with antibiotic saline and used perioperative treatment to prevent aseptic meningitis. The pathohistological diagnosis revealed epidermoid tumor cyst. Postoperative MRI revealed complete resection ( Fig. 1 , D - F ). The patient recovered fully and was neurologically intact. The link to the video can be found at: https://youtu.be/LyWl-KZUSGY .

Microsurgical Treatment of Epidermoids. Case Report and Literature Review

The aim of the research: study the features of surgical treatment of epidermoids.

Materials and methods. We present a literature review and the clinical case of surgical treatment of a patient with epidermoid. We have searched medical databases: Medline, Russian Science Citation Index, EMedicine, United Medical Knowledge Base. We considered the features of the clinic, diagnosis, and surgical intervention. The article presents a clinical example of successful surgical treatment of a patient with an epidermoid cyst of the posterior cranial fossa. The result of the literature review was the writing of a clinical lecture; the current state of the issue of etiopathogenesis, diagnosis and management of patients with epidermoids was studied.

Results. The authors found that total microsurgical removal is the method of choice, and the operative technique should be aimed at preventing postoperative aseptic meningitis. Although it was not possible to establish the cause of the development of aseptic meningitis, the authors assume that the mechanism of its formation lies in the self-breaking of the capsule of the epidermoid cyst, probability of which was confirmed by a number of studies. Further study of this pathology is a promising direction in neurosurgery.

Conclusion. Difficulties in the diagnosis and choice of surgical tactics point at the need for detailed preoperative planning of surgical intervention, performing a precise total removal of a lesion with compliance with preventive measures for aseptic meningitis to improve clinical results and reduce the incidence of perioperative complications.

Endoscopic endonasal resection of epidermoid cysts involving the ventral cranial base

OBJECTIVE

Epidermoid cysts (ECs) commonly extend to involve the ventral cisterns of the cranial base. When present, symptoms arise due to progressive mass effect on the brainstem and adjacent cranial nerves. Historically, a variety of open microsurgical approaches have been used for resection of ECs in this intricate region. In recent years, the endoscopic endonasal approach (EEA) has been proposed as an alternative corridor that avoids crossing the plane of the cranial nerves. To date, there is a paucity of data in the literature regarding the safety and efficacy of the EEA in the treatment of ECs of the ventral cranial base.

METHODS

The authors reviewed a prospectively acquired database of EEAs for resection of ECs over 8 years at Weill Cornell, NewYork-Presbyterian Hospital. All procedures were performed by the senior authors. Standardized clinical and radiological parameters were assessed before and after surgery. Statistical tests were used to determine the impact of previous surgery and tumor volume on extent of resection and recurrence as well as the method of closure on rate of CSF leak.

RESULTS

Between January 2009 and February 2017, 7 patients (4 males and 3 females; age range 16-70 years) underwent a total of 8 surgeries for EC resection utilizing the EEA. Transplanum and transclival extensions were performed in 3 and 5 patients, respectively. Methods of closure incorporated a gasket seal in 6 of 8 procedures and a nasoseptal flap in 7 of 8 procedures. Gross-total resection (GTR) was achieved in 43% of patients, and near-total resection (> 95%) was obtained in another 43%. Complications included diabetes insipidus (n = 2), postoperative CSF leak (n = 2), transient third cranial nerve palsy (n = 1), and epistaxis (n = 1). With a mean follow-up of 43.5 months, recurrence has been observed in 2 of 7 patients. In 1 case, reoperation for recurrence was required 71 months following the initial surgery. Use of the gasket-seal technique with nasoseptal flap coverage significantly correlated with the absence of postoperative CSF leakage (p = 0.018). GTR was achieved in 25% of the patients who had prior surgeries and in 50% of patients without previous resections. The mean volume of cysts in which GTR was achieved (4.3 ± 1.8 cm3) was smaller than that in which subtotal or near-total resection was achieved (12.2 ± 11 cm3, p = 0.134).

CONCLUSIONS

The EEA for resection of ECs of the ventral cranial base is a safe and effective operative strategy that avoids crossing the plane of the cranial nerves. In the authors' experience, gasket-seal closure with nasoseptal flap coverage has been associated with a decreased risk of postoperative CSF leakage.

Surgical Management of Intracranial Giant Epidermoid Cysts in Adult: A Case-Based Update

Epidermoid cysts (ECs) are benign and slow-growing lesions that account for about 0.2%-2% of all intracranial tumors. Symptoms appear slowly and tumors may have already grown to giant proportions when patients receive their first diagnosis. The optimal treatment for ECs is surgical removal, which includes the total resection of the entire capsule of the lesion in order to minimize the risk of malignant transformation associated with partial removal. However, considering the giant size that the ECs can reach at the time of the diagnosis, and their adherence to the surrounding structures, the risks and benefits of total versus subtotal resections in the short- and long-term patients' outcome are still under debate. Here, we report a case of an extensive giant EC and offer a discussion of its characteristics, surgical management, and postoperative outcome, taking a cue to argue about the recent literature based in the latest case studies.

Cerebellar Vermian Epidermoid Tumor: A Report of 2 Cases

BACKGROUND

Epidermoid tumors are rare, benign slow-growing congenital tumors, most frequently located in the cerebellopontine angle of the intracranial cavity. They usually grow to a large size before patients become symptomatic. Although these tumors are amenable to surgery, their adherence to neurovascular structures poses a surgical challenge that results in subtotal resection, thus increasing the risk of recurrence.

CASE DESCRIPTION

We report 2 adult patients whose imaging studies revealed epidermoid tumors located in the cerebellar vermis, an uncommon site for such tumors. The patients presented with variable symptomatology. We highlight the imaging features and challenges of surgery. Both patients had good outcomes, with resolution of symptoms and neurologic deficits.

CONCLUSIONS

A safe complete excision of epidermoid tumor and its capsule is possible with a good understanding of their clinical and radiologic features and a high index of suspicion. To the best of our knowledge, this is the first report of cerebellar vermian epidermoid tumors from sub-Saharan Africa.

Surgical Resection of Cerebellopontine Epidermoid Cysts: Limitations and Outcome

Objective  Epidermoid cysts are benign slowly growing tumors commonly involving the cerebellopontine angle (CPA). The aim of this study was to analyze the surgical limitations, surgical strategies, complications, and outcome of resection of these lesions. Material and Methods  The clinical data and outcome of 32 cases operated for CPA epidermoid between 2007 and 2015 were retrospectively analyzed. The mean follow-up period was 42.6 months, and all patients were followed up at least for a whole year. Results  There were 15 males and 17 females. The median age was 37.6 years. Headache and cranial nerves dysfunction were the most common presenting symptoms. Surgery was performed in all patients using the standard lateral suboccipital retrosigmoid approach. In three cases, microvascular decompression of an arterial loop was performed in addition to tumor excision. Total resection was accomplished in 19 out of 32 cases (59.4%), subtotal resection in 7 cases (21.9%), and only partial excision was achieved in 6 cases (18.7%). There was no recurrence or regrowth of residual tumor during the follow-up period. We had a single postoperative mortality due to postoperative pneumonia and septic shock. New cranial nerves deficits occurred in 15.6% of cases but were transient in most of them. Conclusion  The favorable outcome of total resection of CPA epidermoids should always be weighed against the critical risks that accompany it especially in the presence of tight adhesions to vital neurovascular structures. The retrosigmoid approach is suitable for the resection of these tumors even if they were large in size.

Giant Epidermoid Cyst: A Rare Cause of Temporal Lobe Epilepsy

Introduction  Epidermoid tumors represent approximately 0.3 to 1.8% of all intracranial brain tumors. Only 1.5% of all intracranial epidermoid cysts (ECs) invade the brain and secondary epilepsy is extremely rare. Since August 2014, a 59-year-old male smoker had been presenting bad smell feelings, totaling four episodes with sudden onset and duration of 2 minutes. On September 2014, after a sense of smell episode, it evolved into loss of contact and automatic movements followed by generalized tonic–clonic movements. The brain magnetic resonance imaging revealed an extensive subtemporal lesion affecting anterior, middle, and posterior fossa with invasion of the choroidal fissure and projection to the temporal horn of the lateral ventricle. Pretemporal craniotomy with combined approaches, transsylvian and subtemporal, allowed for the excision of a white keratinized and softened lesion suggestive of EC.

Discussion  The optimal surgical strategy in individuals with ECs and seizures is not established. The evaluation of the cause and risk–benefit must be held to choose the appropriate surgical strategy: lesionectomy, lobectomy, or amygdalohippocampectomy. In this case, a lesionectomy was performed due to an absence of evidence of involvement of hippocampus and amygdala.

Conclusion  Epilepsy secondary to ECs is a rare association. Lesionectomy can be an option with good results without increasing the morbidity.

Endoscopic Treatment of a Third Ventricular Epidermoid Cyst

Epidermoid cyst is a benign and congenital lesion of ectodermal origin. Traditionally, microsurgical techniques are used to treat these lesions, and their occurrence in the third ventricle is rare. Here, the authors report a case of epidermoid cyst in the third ventricle that presented with signs and symptoms of intracranial hypertension, which was treated safely and effectively using neuroendoscopic surgery.

Endoscopic endonasal resection of a giant middle fossa epidermoid cyst

Intracranial epidermoid cysts are rare. We report a case of a 55-year-old man who presented with trigeminal neuralgia and was found, on imaging, to have an epidermoid cyst located in the right middle fossa. He was managed via an entirely endoscopic endonasal approach. Postoperative magnetic resonance imaging confirmed complete removal of the mass, and the patient continued to have complete resolution of symptoms at a 1-year follow-up.