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What is Which of the following is decussated in superior medullary velum? and explain in detail?
ANSWER: (B) 4th nerveREF: Neurology: A Queen Square Textbook - page 516Trochlear nucleus (4th nerve) is located in the midline, just ventral to the cerebral aqueduct. Axons leave the nucleus and course dorsally around the aqueduct, decussates within the superior medullary velum and exit from the midbrain on its dorsal surface."Bilateral 4th nerve palsy may be due to a lesion in the superior medullary velum"