Unimpaired postprandial pancreatic polypeptide secretion in Parkinson's disease and REM sleep behavior disorder.

Background: Pancreatic polypeptide is released immediately after food ingestion. The release is operated by vagal-abdominal projections and has therefore been suggested as a test for vagal nerve integrity. Pathoanatomical and clinical studies indicate vagal dysfunction in early Parkinson's disease (PD).

Patients with idiopathic rapid-eye-movement sleep behavior disorder show normal gastric motility assessed by the 13C-octanoate breath test.

Background: Delayed gastric emptying is a non-motor symptom of Parkinson's disease. Few data exist on gastric emptying in early-stage Parkinson's disease. In idiopathic rapid-eye-movement sleep behavior disorder, a presumable pre-motor stage of Parkinson's disease, gastric emptying has not yet been investigated.

Real-time visualization of altered gastric motility by magnetic resonance imaging in patients with Parkinson's disease.

Gastrointestinal motility is frequently affected in Parkinson's disease (PD) and has even been reported in early stages of PD. We hypothesized that gastric motility can be assessed in vivo by real-time magnetic resonance imaging (MRI), an established, noninvasive method. After an overnight fast and a standardized test meal, 10 patients with PD (six drug naïve, four treated) and 10 healthy volunteers underwent real-time MRI scanning of the stomach.

Assessment of idiopathic rapid-eye-movement sleep behavior disorder by transcranial sonography, olfactory function test, and FP-CIT-SPECT.

Idiopathic rapid-eye-movement (REM) sleep behavior disorder (iRBD) has been suggested to be a risk factor for subsequent development of neurodegenerative disorders, especially Parkinson's disease (PD) and other alpha-synucleinopathies. At present, it is not possible to predict whether or not an iRBD patient will eventually develop PD. Here, we report 5 iRBD patients who underwent a test battery comprising a neurological examination (including UPDRS rating), mini mental state examination testing, transcranial sonography, olfactory function testing, and presynaptic dopamine transporter imaging with FP-CIT-SPECT.