Introduction: Despite over 60 years of experience with cerebrospinal fluid shunts, failure rates remain high and failure causes a variety of non-specific symptoms which can be challenging and costly to work-up in the clinical setting. Current diagnostic modalities to assess shunt patency include head CT, shunt series XR, shunt taps, and radionucleotide studies among others. Each of these exams has associated patient risks including shunt infection and radiation exposure. The ShuntCheck system utilizes a non-invasive transcutaneous temperature probe to assess shunt patency and has no known associated risks making it an enticing alternative to standard methods of shunt interrogation.
Methods: Novel mobilized computer workstations with ShuntCheck software capabilities were developed for inpatient assessments. Additionally, an algorithmic model was developed to assess the cost-effectiveness of using ShuntCheck to evaluate shunt patency compared to radionucleotide studies (See Figure 1). Sensitivities and specificities of diagnostic modalities were obtained from literature review and costs were obtained from our hospital billing department.
Results: Using our proposed algorithm, screening patients for shunt failure using ShuntCheck was cost-effective in the case of a patent shunt after nine patients were screened. The differential cost savings in this setting was $505. Cost was comparable between the two screening arms when assessing patients with slowed shunt flow. ShuntCheck was not cost-effective to screen patients with truly obstructed shunts, however this was due to use of confirmatory radionuclide studies in our model.
Conclusions: ShuntCheck is a safe, inexpensive, and accurate method of assessing patency of CSF shunts. Further studies are needed to confirm the sensitivity and specificity of ShuntCheck, however given current estimates it may replace radionucleotide studies as the gold standard exam for evaluating shunt patency.
Patient Care: Adapting ShuntCheck for the inpatient evaluation of patients with potential shunt failure will likely decrease both visit cost and patient exposure to radiation or other invasive diagnostic tests.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Understand the rationale behind the ShuntCheck system
2) Appreciate how ShuntCheck is easily adaptable to the inpatient setting
3) Critically analyze costs associated with evaluating a patient for shunt failure.
4) Develop an opinion on the merits of expanding the role of ShuntCheck
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