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 of the lumbar spinal drainage trial in patients with normal pressure hydrocephalus.