Normal pressure hydrocephalus plus atypical presentation with symptomatic resolution following the restoration of CSF flow: illustrative case.

backgroundNormal pressure hydrocephalus (NPH) is a condition characterized by enlarged intracerebral ventricles with normal intracranial pressure. The typical clinical presentation includes cognitive decline, gait disturbances, and urinary incontinence. While the classic triad of symptoms is well documented, atypical presentations, including focal deficits and aphasia, pose significant diagnostic challenges. OBSERVATIONS: This is the case of a previously healthy 70-year-old patient presenting with rapidly progressive gait disturbances, right hemiplegia, cognitive decline, and mutism. The focal presentation suggested a left hemispheric cerebrovascular insufficiency. A comprehensive diagnostic workup, including serial imaging, lumbar punctures, and electroencephalography, was undertaken given diagnostic uncertainty. Initial evaluations suggested a left hemispheric stroke or neurodegenerative process, ultimately delaying the definitive diagnosis and treatment of NPH. MRI revealed progressive ventriculomegaly and white matter changes prompting a lumbar drain trial. This yielded clinical improvement and ventriculoperitoneal shunt placement. Postoperatively, the patient had complete resolution of symptoms and returned to a normal functional status within 6 weeks. LESSONS: This case demonstrates the diagnostic challenges in differentiating NPH from stroke or neurodegenerative disorders. Recognizing its varied presentations and distinguishing them from other diseases is crucial for initiating appropriate treatment. Early intervention improved this patient's outcome and prevented unnecessary morbidity, demonstrating the significant impact of accurate and timely diagnosis. https://thejns.org/doi/10.3171/CASE25620.