Dyspnea as a side effect of subthalamic nucleus deep brain stimulation for Parkinson's disease.

Bilateral subthalamic nucleus deep brain stimulation for Parkinson's disease improves limb function. Unpublished observations from our clinic noted that some subthalamic nucleus deep brain stimulation patients complain of post-operative dyspnea. Therefore, we designed a prospective, longitudinal study to characterize this in greater depth. We used specific questionnaires to assess dyspnea in patients with electrodes in the subthalamic nucleus (n=13) or ventral intermediate thalamus (n=7). St. George's Hospital Respiratory Questionnaire symptom subscale scores were greater in subthalamic nucleus patients (median=18.60, interquartile range=40.80) than ventral intermediate thalamus patients (median = 0.00, interquartile range=15.38) at greater than 6 months post-operatively (p<0.05). Several of the subthalamic nucleus patients exhibited functional impairments as judged by the St. George's Hospital Respiratory Questionnaire impact subscale, the Medical Research Council Dyspnoea Scale, and the Dyspnoea-12 Questionnaire. There was no correlation between limb function ratings, stimulation parameters, or precise electrode position and dyspnea severity. We have shown, for the first time, that dyspnea can be a side effect of subthalamic nucleus deep brain stimulation, and that this dyspnea may be highly disabling.

Idiopathic normal pressure hydrocephalus: an important differential diagnosis.

Idiopathic normal pressure hydrocephalus, an uncommon but important differential diagnosis for ataxia, cognitive impairment and urinary incontinence, is surgically treatable, unlike many of its differential diagnoses. This article discusses its assessment, investigation and therapeutic interventions.

The periaqueductal grey area and control of blood pressure in neurodegeneration.

The periaqueductal/periventricular grey area (PAG/PVG) is a midbrain nucleus with an important role in pain signalling and autonomic control. We present the case of an initially hypertensive man who developed a presumed neurodegenerative disorder over a decade, characterised by progressive right-sided chronic pain, extra-pyramidal symptoms and autonomic dysfunction including postural hypotension, sleep apnoea, and bladder instability. He underwent a variety of treatments for his symptoms, including deep brain stimulation (DBS) of the PAG/PVG. 24-h blood pressure monitoring was carried out 1 and 5 years after implantation. Although the DBS initially produced a significant reduction in blood pressure, the effect was significantly reversed when the same tests were repeated 5 years after surgery. This may imply a functional involvement of the PAG/PVG in the neurodegenerative process.

Neurotrauma outside the high-income setting: a review of audit and data-collection strategies.

OBJECTIVE: To review the sparse literature that exists on the topic of head injury assessment and management outside high-income settings and attempt to: 1) identify strengths and weaknesses of the currently published clinical data relating to head injuries in lower-income countries; and 2) consider specific objectives for future head injury research in the resource-limited setting. If levels of excellence in neurosurgery are to be sustainably achieved outside high-income countries, there must be good systems of research and audit in place both to identify where development is needed and to evaluate the efficacy of development projects already in progress. METHODS: We performed a MEDLINE search of publications between 1980 and 2010 by using the search terms head injuries/craniocerebral trauma/neurotrauma and developing world/developing nations. Information was extracted and compared between publications by using our local head injury evaluation and audit database (OxHEAD) as a quality standard. RESULTS: The issue of traumatic brain injury management in low-income countries is underrepresented in the international literature relative to the scale of the problem. However, epidemiologic data generally are better reported than data relating to in-hospital care and follow-up, which suffers as a result of heterogeneous data collection and categorization techniques. CONCLUSION: The use of standardized scoring systems and outcome measures is likely to improve the comparability of data between studies. A multicenter collaborative approach towards data collection in resource-limited settings may be the most efficient and productive strategy for future research.

Switching off micturition using deep brain stimulation at midbrain sites.

Most of the time the bladder is locked in storage mode, switching to voiding only when it is judged safe and/or socially appropriate to urinate. Here we show, in humans and rodents, that deep brain stimulation in the periaqueductal gray matter can rapidly and reversibly manipulate switching within the micturition control circuitry, to defer voiding and maintain urinary continence, even when the bladder is full. Manipulation of neural continence pathways by deep brain stimulation may offer new avenues for the treatment of urinary incontinence of central origin.