Objective:

To report a unique case of a chronic PICA aneurysm causing progressive gait imbalance and falls.

Background:

PICA aneurysms pose a significant risk for subarachnoid hemorrhage (SAH). Presentation varies based on the anatomical location and compression of nearby structures. However, the presence of an unruptured PICA aneurysm as a cause of a patient’s imbalance has rarely been reported. 

Design/Methods:

Case Report

Results:

An 82-year-old woman with hypothyroidism, osteoporosis, and a several year history of recurrent falls, gait instability, syncope, and left hemifacial paralysis presented to our clinic for evaluation of recurrent falls and imbalance. The exam revealed a left facial and a partial CN III palsy. Gait showed a normal stride, but with lateropulsion, mild stooping, and inability to perform tandem walking. The patient also had asymmetric hearing with finger rubbing (L>R) and brisk deep tendon reflexes (L>R). Despite multiple falls and visits to primary care and other neurology clinics, no clear cause has been identified. A brain MRI performed 15 years ago revealed a partially thrombosed, calcified aneurysm of the left PICA at the cerebellopontine angle (CPA) region. A repeat brain MRI demonstrated a large, thrombosed PICA aneurysm with brainstem shift.

Conclusions:

Diagnosis relies on imaging with CTA or MRA while management includes careful monitoring or surgical interventions depending on size and risk factors. This case demonstrates the importance of identifying PICA aneurysms near the CPA as a potential cause of chronic gait instabilities, particularly in the elderly patient, and to always consider second level causes of gait disorders in the elderly.