Objective:

To evaluate whether a valve-agnostic cranial implant allows reliable reprogramming of programmable ventriculoperitoneal (VP) shunt valves in normal pressure hydrocephalus (NPH), and to assess clinical outcomes. 

Background:

Programmable VP shunts permit noninvasive adjustment of opening pressure, enabling individualized titration of cerebrospinal fluid drainage for symptomatic benefit or to address over- and under-drainage. Adjustments are frequent in clinical practice, making consistent access to valve reprogramming essential. The valve-agnostic cranial implant is a low-profile cranial mount that seats the valve flush within a partial-thickness craniotomy, thus involving a “countersunk” configuration. This design reduces scalp tension and wound complications compared to conventional subgaleal placement. However, whether this recessed configuration affects ease or reprogramming outcomes has not been well-characterized. 

Design/Methods:

Single-center retrospective case series of adults with NPH who underwent VP shunting with a valve-agnostic cranial implant between 2019 and 2023. Outcomes included frequency of successful valve reprogramming using standard manufacturer tools, clinical improvement (gait, continence, cognition), and adverse events. 

Results:

Twenty-five patients (mean age 76.4 ± 10.3 years) were included. All valves were successfully reprogrammed during follow-up, with a mean of 2.3 ± 1.4 valve-setting adjustments, reflecting typical postoperative titration patterns. There were no intraoperative complications or postoperative infections within 30 days. One wound dehiscence required revision, and no valve dislodgment occurred. Clinical improvement was observed in gait (18/25; 72%), urinary incontinence (9/25; 36%), and cognition (8/25; 32%). 

Conclusions:

Programmable valves implanted with a valve-agnostic cranial implant remained reliably reprogrammable using standard devices. Early clinical outcomes were comparable to traditional subgaleal placements, suggesting preserved programming accessibility with potentially reduced soft-tissue complications. These results support the feasibility of outpatient reprogramming workflows and warrant future comparisons with fixed-pressure or standard configurations.