Question

A 56 year old woman visited her family doctor for evaluation of a headache that had persisted for nearly a month. Upon questioning the patient, the doctor learned that her left arm, as she put it, "was a bit unwieldy, hard to control and weak." Through examination, the doctor determined that the entire left upper extremity was generally weak. He also found weakness, although less significant, of the left lower extremity. Sensation in the limbs seemed to be normal, although mild rigidity and hyperactive reflexes were present. Expressing concern, the doctor told the patient that she needed a CT scan of her head and explained that there could be a problem within the brain, possibly a tumor or other lesion. The doctor then picked up the phone and contacted a radiologist. After explaining the patient's case, the doctor remarked parenthetically that he believed he knew where the problem was located.

1) Why did the doctor suggest to the patient that there might be a problem within her brain when the symptoms were weakness of the extremities, and then just on one side of her body?

2) How would he know the location of the suspected brain tumor?

3) In which side of the brain and in which lobe would it be?

4) Explain the muscle weakness in terms of neuronal pathways from the brain to the periphery.

Answer 1

Please find the answer below.

1) patient have complains of persistent headache along with weakness of left side of the body . She shows hyperrefexes and rigid limbs , these are signs of upper motor neuron lesion..ie, lesions of brain or spinal cord. Since patient have headache, it shows there is a space occupied lesion of brain or any haemorrhage or lack of blood supply to areas of brain.

2) suspected lesion or tumour will be in right side of brain area. Because there is decussation of motor fibres at medulla, right side of brain control the motor fibres of left side of body.

3) lesion will be in right side of brain and since her upper extremity is more involved, the areas where middle cerebral artery supply is there ,are areas of lesion. It includes internal capsule, motor and pre motor cortex

4)Motor tracts are corticospinal and corticobulbar tracts. Corticospinal tract is as follows

Corona radiata - motor area of cortex -midbrain - medulla - spinal cord - motor nerves - motor unit of muscle