Microsurgical Gross Total Resection of a WHO Grade II Cerebellopontine Angle Ependymoma in an Adult

Cerebellopontine angle ependymoma presenting as isolated hearing loss in an elderly patient: A case report and literature review

Background:

Ependymoma is an uncommon tumor accounting for approximately 1.9% of all adult central nervous system tumors. Ependymomas at the cerebellopontine angle (CPA) are even more rare and only previously described in isolated case reports. Typically, acoustic neuromas and meningiomas represent the bulk of adult CPA tumors. Diagnosis can be challenging, as ependymomas have clinical findings and imaging characteristics that overlap with more common tumor histologies at the CPA.

Case Description:

We present the case of a 70-year-old male patient with progressive, isolated left-sided hearing loss found to have a World Health Organization (WHO) Grade II CPA ependymoma, representing one of the oldest recorded patients presenting with this primarily pediatric malignancy in this unique location. The patient presentation with isolated hearing loss was particularly unusual. When associated with neurologic deficits, CPA ependymomas more characteristically result in facial nerve impairment with fully preserved hearing, while vestibular schwannomas tend to present with isolated hearing loss. The standard of care for pediatric ependymomas is maximal safe resection with adjuvant radiotherapy, but treatment paradigms in adult CPA ependymoma are not well defined particularly for WHO Grade II disease. After resection, he received adjuvant radiation to decrease the risk of local recurrence. Twenty-nine months after resection, the patient remains free of treatment-related toxicity or disease recurrence.

Conclusion:

We review this patient’s clinical course in the context of the literature to highlight the challenges associated with timely diagnosis of this rare tumor and the controversial role of adjuvant therapy in preventing local recurrence in these patients.

Clinical Importance of the Posterior Inferior Cerebellar Artery: A Review of the Literature

The posterior inferior cerebellar artery (PICA), with its unique anatomical complexity, is of great clinical importance and involved in many diseases including aneurysm, ischemic stroke, neurovascular compression syndrome (NVCS), arteriovenous malformation (AVM), and brain tumor. However, a comprehensive systematic review of the importance of the PICA is currently lacking. In this study, we perform a literature review of PICA by searching all the associated papers in the PUBMED database hoping to provide a better understanding of the artery. The PICA has tortuous and variable course and territory, divided into 5 segments. Various aneurysms involving PICA were not uncommon, of which the treatment is challenging. The PICA infarct typically manifests lateral medullary syndrome (LMS) and is more likely to cause mass effects. The PICA frequently compresses the medulla and the cranial nerves resulting in various neurovascular compression syndromes (NVCS). Arteriovenous malformation (AVM) fed by PICA are associated with aneurysm and dissection which have high risk of rupture and worse outcome. PICA injured by head trauma can cause fatal SAH. VA terminating in PICA probably cause Bow hunter's syndrome (BHS). The PICA supplies many brain tumors and can be used in intracerebellar chemotherapy. The PICA can be exposed and injured during surgeries especially in telovelar approach, and it also plays an important role in bypass surgeries, hinting the surgical importance of PICA. In conclusion, PICA is very important in clinical practice.

Clinical Importance of the Posterior Inferior Cerebellar Artery: A Review of the Literature

The posterior inferior cerebellar artery (PICA), with its unique anatomical complexity, is of great clinical importance and involved in many diseases including aneurysm, ischemic stroke, neurovascular compression syndrome (NVCS), arteriovenous malformation (AVM), and brain tumor. However, a comprehensive systematic review of the importance of the PICA is currently lacking. In this study, we perform a literature review of PICA by searching all the associated papers in the PUBMED database hoping to provide a better understanding of the artery. The PICA has tortuous and variable course and territory, divided into 5 segments. Various aneurysms involving PICA were not uncommon, of which the treatment is challenging. The PICA infarct typically manifests lateral medullary syndrome (LMS) and is more likely to cause mass effects. The PICA frequently compresses the medulla and the cranial nerves resulting in various neurovascular compression syndromes (NVCS). Arteriovenous malformation (AVM) fed by PICA are associated with aneurysm and dissection which have high risk of rupture and worse outcome. PICA injured by head trauma can cause fatal SAH. VA terminating in PICA probably cause Bow hunter's syndrome (BHS). The PICA supplies many brain tumors and can be used in intracerebellar chemotherapy. The PICA can be exposed and injured during surgeries especially in telovelar approach, and it also plays an important role in bypass surgeries, hinting the surgical importance of PICA. In conclusion, PICA is very important in clinical practice.