Question

What's the most common cause of "locked in syndrome" (quadriplegia & inability to speak in otherwise cognitively normal person, with preserved eye muscle function)?

Answer 1

The most common cause of locked-in syndrome is a vascular lesion in the brainstem, such as a pontine hemorrhage or infarct, leading to quadriplegia and inability to speak with preserved consciousness.

Step-by-step explanation:

The most common cause of locked-in syndrome is a vascular lesion in the brainstem, particularly a pontine hemorrhage or infarct. Locked-in syndrome is characterized by quadriplegia and anarthria (inability to speak) but with preservation of consciousness and eye movements. Patients are cognitively aware but cannot move or communicate verbally due to complete paralysis of nearly all voluntary muscles in the body, except for the eyes.

Brainstem strokes that can lead to locked-in syndrome are often caused by an embolus or a hemorrhage in the part of the brain that contains the majority of the cranial nerve nuclei and is responsible for transmitting signals for motor function.

As the condition progresses, patients may require a brain-computer interface to communicate. Treatment and recovery vary depending on the severity and cause of the brain injury. While some recoveries are possible, they are typically limited and the condition is generally considered irreversible.