This report proposes a new approach to assess dysarthria in patients with brainstem infarction by involving familiar individuals. Collaboration provides valuable insights compared to subjective traditional methods. A man in his 70s presented with resolved positional vertigo. Standard neurological tests showed no abnormalities, and inquiries with the patient’s friend did not reveal voice changes. While inquiring about voice changes with family, friends, and acquaintances is a common practice in clinical settings, our approach involved the patient calling out to his friend from a distance. Despite the physician detecting no abnormalities, the friend noticed a lower voice. Subsequent magnetic resonance imaging (MRI) confirmed brainstem infarction. Early and subtle symptoms of brainstem infarction pose a detection challenge and can lead to serious outcomes if overlooked. This report provides the first evidence that distance calling can detect subtle voice changes associated with brainstem infarction potentially overlooked by conventional neurological examinations, including inquiries with individuals familiar with the patient’s voice. Detecting brainstem infarction in emergency department cases is often missed, but conducting MRIs on every patient is not feasible. This simple method may identify patients overlooked by conventional screening who should undergo neuroimaging such as MRI. Further research is needed, and involving non-professionals in assessments could significantly advance the diagnostic process.