Giant cystic intradural extramedullary pilocytic astrocytoma of Cauda equina
A 20-year-old male patient presented to us with complaints of progressive weakness in bilateral lower limbs, saddle anesthesia and bladder dysfunction for past 2 years. Clinical examination revealed weakness of bilateral lower limbs (Medical Research Council grade: 4/5), asymmetrical sensory loss in bilateral L5-S3 distribution. Patient had Foley's catheter in situ. Rest of the neurological examination was normal. Patient did not have any neurocutaneous markers.\nMagnetic resonance imaging (MRI) of the lumbosacral spine showed an intradural lesion that extended from L4 to S4 vertebral segments causing scalloping of the posterior surface of vertebral bodies and expansion of the spinal canal. There was no extension into the vertebral foramina. The lesion was hypointense on T1-weighted images and hyperintense on T2-weighted images. The conus medullaris was low lying and reached up to the level of L4 vertebral body. The tumor was abutting the conus medullaris. The wall of the lesion showed intense contrast enhancement. The lesion did not extend into the foramina []. A screening MRI of the rest of the cranial-spinal axis was done to rule out any other lesion was done. MRI of the rest of the spine was normal []. However, patient was found to have right cerebellopontine angle enhancing lesion suggestive of acoustic schwannoma and another lesion in the suprasellar region suggestive of hypothalamic glioma [].\nPatient was operated in the prone position. Midline incision was made. The posterior bony elements were absent in the sacral region. A large intradural cystic lesion, with a thin cyst wall formed by the tumor tissue, was present in the lumbosacral region. The cyst contained xanthochromic fluid. Yellowish, soft, mildly vascular tumor was covering the nerve roots of Cauda equina and the filum terminale. The wall of the tumor and the filum terminale covered with the tumor were removed. The tumor draping the nerve roots was left behind as it entailed the risk of causing neurological deficits. Post-operative course was uneventful. Patient developed no fresh neurological deficits. Histopathological examination showed features consistent with pilocytic astrocytoma []. As the patient was asymptomatic for intracranial lesions a decision to conservatively follow the patient was taken.\nDuring follow-up, patient's bladder dysfunction improved gradually and presently patient is able to void himself. However, patient's motor and sensory symptoms showed neither improvement nor deterioration during 2 years follow-up.\nFollow-up MRI revealed recurrence of the lesion []. The intracranial lesions did not increase in size during follow-up. Patient is currently awaiting second surgery.