Cervical spine disease may result in a negative lumbar spinal drainage trial in normal pressure hydrocephalus: Case report

OBJECTIVE: In this case report, we present a patient with normal pressure hydrocephalus in whom a lumbar drainage trial yielded a false-negative result secondary to cervical spondylosis. CLINICAL PRESENTATION: An 80-year-old woman presented with classic symptoms of normal pressure hydrocephalus as well as evidence of cervical myelopathy. Magnetic resonance imaging of the brain and spine showed enlarged ventricles and single-level cervical canal narrowing. INTERVENTION: An initial lumbar drainage trial was performed, which revealed negative results. The patient then underwent cervical decompression and fusion. Despite this procedure, the patient's symptoms continued to worsen. A repeat lumbar drainage trial was performed with positive results. Subsequently, a ventriculoperitoneal shunt was placed, resulting in significant improvement of her symptoms. CONCLUSION: This case report illustrates how altered cerebrospinal fluid flow dynamics may impact the accuracy ofthe lumbar spinal drainage trial in patients with normal pressure hydrocephalus.