For medicolegal purposes, before videotaping a patient exam, written informed consent must be obtained from the patient. The physician should keep this consent together with all other medical documents. We find it preferable to videotape the signed consent form so that it is located directly with the patient's examination on the same video. Written informed consent is also important for facilitating sharing of the videotape with other providers, if needed. All relevant documents should be videotaped, such as the Montreal Cognitive Assessment, handwriting, and Archimedes spiral drawing, given that these tests frequently add valuable information regarding the diagnosis. Ideally, the videotape should be systematic and follow a consistent pattern. Though every physician will have his own style of examining the patient, we have found it works best to first videotape the patient while sitting, and then proceed in the examination in a rostral-caudal sequence, comparing the two sides after each exam maneuver. This is followed by having the patient arise from a sitting to a standing position (initially without pushing off, if the patient is able, and then pushing off with his or her hands if the patient fails to arise initially). The patient is then asked to walk for at least 5 meters in each direction in an unimpeded corridor with at least two turns to assess gait and turning. Walking is best observed by videotaping the patient walking away from and toward the camera, such that both arms and legs are visible at all times, rather than in a plane 90 degrees from the camera, from which one cannot observe the two sides of the patient's body at the same time. Postural reflexes are assessed with the pull test, which is often abnormal in classical parkinsonism, but may also be helpful in distinguishing between other movement disorders. For example, patients with Huntington's disease, dopa-responsive dystonia, and MSA frequently have positive pull tests, in contrast to patients with other forms of chorea, dystonia, and cerebellar ataxia, which do not affect postural stability. During the pull test or gait assessment, posture may be recorded as well. After these standing procedures, it is useful to observe the patient in the act of sitting down. This concludes the standard videotape. If clinically indicated, additional videotaping can be done to demonstrate the effect of postures or positions (e.g., lying supine) or specific tasks such as writing, talking, singing, biting, chewing, swallowing, drinking, holding objects, pouring water into a cup, running, tandem walking, walking backward, or standing on one leg.
In almost all circumstances, the videotape can be performed with the patient fully clothed. In specific cases, it may be necessary to remove specific items of clothing obstructing anatomical locations of interest, as in, for example, foot dystonia or spinal myoclonus. The videotape is not uniform for all patients, although the general guidelines do apply to all cases. Different symptoms require focusing on specific tasks.
While videotaping a patient, the camera should be placed directly in front of the patient (rather than off to one side) in order to observe for asymmetries between the two sides of the body. Any objects impairing the camera's view should be removed and care should be taken to avoid videotaping bystanders or family and friends accompanying the patient. The room should be well lit and be large enough to include the patient's entire body within the camera screen. Avoid backlighting by not aiming the camera toward windows or lamps. The background noise (air conditioners and fans) should be minimized in order not to miss relevant clinical signs, such as slurred speech or voice tremor. The photographer should alternately zoom in on the area of interest being examined and zoom out to show the whole body during motor activation. This can sometimes enhance involuntary movements in other parts of the body,[7, 8] or cause the disappearance of movements by distraction as occasionally observed in patients with psychogenic movement disorders. The patient should sit with arms and legs uncrossed (hands in lap). The camera battery should be fully charged before beginning to videotape in order to maintain continuity of the exam. We recommend videotaping the patient at the first clinic visit in order to have a baseline audiovisual record with which to compare future clinical evaluations. Preferably, the camera operator is not simultaneously examining the patient given that some features of the exam may not be videotaped by the examiner. In the remainder of this article, we offer specific recommendations for videotaping an examination tailored to several common movement disorders.