The Ultrasonographic Evaluation of Abdominal Accessory Respiratory Muscle Thickness in Patients With Parkinson's Disease: Correlation With Disease Severity and Expiratory Respiratory Muscle Strength

This study uses ultrasound imaging to measure the thickness of breathing muscles in the abdomen in people with Parkinson's disease, and examines how these muscle changes relate to disease severity and the strength of muscles used for breathing out. **You may be eligible if...** - You are over 18 years old - You have been diagnosed with Parkinson's disease at stages 1, 2, or 3 on the Modified Hoehn and Yahr scale (mild to moderate) - Your cognitive function is relatively preserved (MMSE score above 23) - Your BMI is under 30 **You may NOT be eligible if...** - You are an active smoker - You have an active chest disease - You have hemodynamic instability or unstable vital signs - Your Parkinson's disease is not well controlled with medication - You have Parkinson Plus syndrome (a related but different condition) Talk to your doctor to see if this trial is right for you.