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Blood-brain barrier integrity in a zolpidem-responder patient
N E Nyakale1, R P Clauss, H W Nel
1Nuclear Medicine Department, University of Pretoria, South Africa.
Abstract:
A 27-year-old neurologically disabled but fully conscious male zolpidem-responder patient was investigated for blood brain barrier (BBB) dysfunction 5 years after a traumatic brain injury. A baseline single-photon emission computed tomography (SPECT) technetium-99m-labelled hexamethylpropylene amine oxime (99mTcHMPAO) brain scan was performed and the patient was administered 10 mg zolpidem daily. The patient was rescanned 2 weeks later when 99mTcHMPAO was injected 1 hour after zolpidem application. SPECT technetium-99m-labelled diethylene-triamine-pentacetic acid (99mTcDTPA) BBB scans were also performed before and after zolpidem treatment. There was decreased uptake of 99mTcHMPAO in the left frontoparietal brain region, left temporal region and left thalamus on baseline scanning; this improved within 1 hour after zolpidem treatment at the follow-up scan. The 99mTcDTPA scan remained within normal limits before and after zolpidem treatment. The patient's neurological disabilities, especially coordination, speech and gait, improved markedly. The Barthel Index remained normal, but the Tinetti falls efficacy scale improved from 21/100 to 15/100. The results implied that the underlying cause for the patient's long-term neurological disability and brain suppression was not due to a long-term dysfunctional BBB.
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