Visual Disturbance Following Shunt Malfunction in a Patient With Congenital Hydrocephalus

Abstract

A 25-year-old woman presented with complaints of nausea and headache. She had been treated with a ventriculoperitoneal shunt for hydrocephalus when she was 7 months old. Her bilateral optic discs showed moderate atrophy. Right visual acuity allowed only perception of hand movement and left visual acuity was 0.02 (1.2). Computed tomography (CT) showed mild ventricular dilation but no periventricular lucency. Intracranial pressure (ICP) was not high when the shunt valve was punctured. Her visual acuity deteriorated 5 days after the consultation. She was referred again 8 days after the first consultation. The bilateral optic discs were completely pale. Both pupils were dilated on admission, and the bilateral direct light reflexes were absent. The patient could slightly detect only green light stimulus. CT showed moderate enlargement of the ventricle. ICP was 47 cmH 2 O when the shunt valve was punctured. Shuntgraphy showed obstruction of the shunt at the distal end of peritoneal catheter. Emergent total shunt revision was performed. She could detect dark stimulus and the still-dilated left pupil had recovered direct light reflex on the next day. The visual acuity was 0.01 (0.7) on the left 6 months after the operation, although she was blind in the right eye and the bilateral optic discs were completely pale. Visual loss associated with shunt failure remains a major morbidity in shunted congenital hydrocephalus. Early diagnosis and shunt revision may allow visual recovery.

Occam's razor in the management of ventriculoperitoneal shunt dysfunction: Diagnosis and management of an unusual pediatric case

“…[ 6 ] Decreased visual acuity has rarely been documented in the literature but is considered an atypical presentation along with other presentations such as seizures, abdominal pseudocyst, syringomyelia, cranial nerve palsies, and hemiparesis. [ 3 4 6 7 ] Although rare, decreased visual acuity could be a portent of permanent visual impairment such has been reported in 1.8% of all children experiencing an episode of raised intracranial pressure due to shunt malfunction. [ 7 ] It has also been reported that in such cases the patient need not have features of raised intracranial pressure or papilledema.…”

“…[ 3 4 6 7 ] Although rare, decreased visual acuity could be a portent of permanent visual impairment such has been reported in 1.8% of all children experiencing an episode of raised intracranial pressure due to shunt malfunction. [ 7 ] It has also been reported that in such cases the patient need not have features of raised intracranial pressure or papilledema. [ 2 3 4 7 ] Cerebral infarcts in the posterior cerebral artery territory have been documented.…”

“…[ 7 ] It has also been reported that in such cases the patient need not have features of raised intracranial pressure or papilledema. [ 2 3 4 7 ] Cerebral infarcts in the posterior cerebral artery territory have been documented. [ 3 ] There are reports of patients presenting with isolated oculomotor paresis as the only clinical sign of hydrocephalus.…”

“…The radiology may be deceptive, and there have been reports with brain scans revealing normal-sized ventricles. [ 1 3 4 7 ] In one study, there was 84% correlation between the diagnosis of shunt malfunction and change in the size of the ventricles on CT scan, but in comparison with a baseline CT scan, prior to the malfunction. [ 6 ] In the present case, there was no change in the size of the ventricles as compared to previous scans on the initial CT scan.…”

“…[ 7 ] Alternately, it has been hypothesized that a VP shunt done early in life may be responsible for early sutural closure and sub-ependymal gliosis which makes the ventricular system resistant to subsequent dilatation when a shunt malfunction occurs, thus being responsible for normal appearing ventricles on a CT scan. [ 7 ]…”