Case 179

Basic Human Neuroanatomy

A Clinically Oriented Atlas

Case History #179

Date of Consultation: 5-3-1990

HISTORY OF PRESENT ILLNESS:

This 58-year-old right-handed white male retired engineer was referred for neurologic consultation because of sensory complaints involving the tongue. These symptoms began in March of 1987, shortly after he underwent a craniotomy.

Prior to his craniotomy in March 1987, the patient experienced a few episodes of “losing track of where he was”. Because of these episodes, an imaging procedure was performed which demonstrated an abnormality. Because of this abnormality he underwent a craniotomy.

Since his operation, he has been bothered by a soreness and irritability of the right side of the tongue, especially when using it to speak, eat, or manipulate food. He also noticed numbness and tingling in the right perioral region and the lateral aspect of the right side of the nose. Since the operation, he also noted predominantly horizontal (side-by-side) diplopia, especially in right gaze. Immediately after the operation, he also noted weakness of the right side of the face, consisting of difficulty in closing the eye completely and moving the right side of the mouth. This facial weakness has improved somewhat in the past two years. Lastly, prior to the operation he experienced ringing in his right ear. This symptom has actually worsened since the operation, and his hearing in the right ear worsened after the procedure.

NEUROLOGICAL EXAMINATION:

Mental Status Exam: Intact.

Cranial Nerves: Sensation of smell was absent on the right and present on the left. Visual acuity was J16 in the right eye and J1 in the left eye with his glasses. Visual field and funduscopic examinations were unremarkable. External ocular movement testing revealed an esotropia and slight hypertropia of the right eye in primary gaze. Abduction of the right eye was limited and horizontal diplopia ensued with attempted right gaze. He was able to fuse the double images with left gaze, especially with his head tilted slightly downward and to the right. Ductions in the left eye were completely normal. Pupils were 5 mm, round, and reactive to light. There was no ptosis present. Sensory testing of the Vth cranial nerve revealed hypalgesia and hypesthesia involving all 3 divisions of the right trigeminal nerve with a mild to moderate degree of hyperpathia and allodynia also present, especially in the maxillary and mandibular divisions of V. This hyperpathic response was also present on the right side of the tongue. With maximal mouth opening, the jaw deviated slightly to the right. A very mild weakness of wrinkling the forehead, eyelid closure, and grimacing was present on the right side. Hearing was diminished in the right ear. Lower cranial nerve functions were normal.

Motor System: There was no evidence of focal or generalized muscular atrophy. There were no fasciculations. Muscle tone and power were normal in all 4 limbs.

Reflexes: Deep tendon reflexes were equal and symmetric except for absent ankle jerks bilaterally. Plantar reflexes were flexor bilaterally.

Sensory System: All modalities of sensation, including cortical sensations, were normal.

Cerebellar Function: The patient performed all cerebellar functions normally.

Gait and Stance: Regular and tandem gait were performed normally, and the Romberg test was negative.

Questions:

1. Was the involvement in this case intrinsic to or extrinsic to the central nervous system?

2. List all of the possible structures that could be involved by the pathologic process to produce each of the abnormal signs and symptoms experienced by this patient.

3. Indicate the anatomical location of the pathologic process in this case. Include the side of involvement.

4. In general, what type of pathologic process do you think is involved in this case? What other differential diagnostic considerations would you entertain?

5. What diagnostic procedure(s) would you have undertaken prior to this patient’s surgery?

Answers