Deck 18: The Eye and the Ear

Question 1

A 49-year-old woman was found on ophthalmoscopic examination to have edema of both optic discs (bilateral papilledema) and congestion of both retinal veins. The cause of the condition was found to be a rapidly expanding intracranial tumor.

-The following statements concerning this patient are correct except which?

A) An intracranial tumor causes a rise in cerebrospinal fluid pressure.
B) The optic nerves are surrounded by sheaths derived from the pia mater, arachnoid mater, and dura mater.
C) The intracranial subarachnoid space extends forward around the optic nerve for about half its length.
D) The thin walls of the retinal vein will be compressed as the vein crosses the extension of the subarachnoid space around the optic nerve.
E) Because both subarachnoid extensions are continuous with the intracranial subarachnoid space, both eyes will exhibit papilledema and congestion of the retinal veins.

Answer 1

The intracranial subarachnoid space extends forward around the optic nerve for about half its length.

Question 2

A 33-year-old woman was riding her bicycle when she swerved to avoid a pothole and lost her balance. She then crashed and hit her head hard on the sidewalk. When she regained consciousness in the hospital, it was immediately noted that she had medial strabismus (squint) of her left eye.

-Which eye muscle was paralyzed in this injury?

A) The medial rectus muscle
B) The inferior rectus muscle
C) The superior rectus muscle
D) The lateral rectus muscle
E) The superior obliques muscle

Answer 2

The lateral rectus muscle

Question 3

An 18-year-old student went to the clinic complaining of an acute tender area on the middle of his right upper eyelid. Examination revealed a localized red, indurated area on the eyelid margin. Close inspection showed a yellowish spot in the center of the swelling. Gentle eversion of the lid showed no evidence of swelling on its posterior surface. What is the diagnosis? Which anatomic structure(s) is (are) involved in the inflammatory process? On which part of the eyelid does the abscess tend to point?

Answer 3

The student had a hordeolum or stye in his right eye. The usual cause is a staphylococcal infection of the eyelash follicle, the sebaceous gland of Zeis, or the ciliary gland of Moll. The suppurative infection tends to point on the anterior part of the lid margin. Repeated multiple styes tend to occur as the result of spread of infection along the eyelid margin.

Question 4

A 13-year-old schoolboy was hit in the left eye by another boy during recess. During the next hour, both the eyelids of the victim swelled up until he could barely see. Examination in the emergency department revealed a bluish-red discoloration of both eyelids of his left eye with narrowing of the palpebral fissure. The discoloration extended to the forehead and the left cheek. Careful separation of the eyelids showed a localized hemorrhage of the inferolateral part of the bulbar conjunctiva (part of the conjunctiva adherent to the sclera of the eyeball). When the conjunctiva was gently moved with the tip of the examiner's little finger, the hemorrhage moved also.
When the patient was asked to look medially, the physician could clearly see the posterior limit of the conjunctival hemorrhage. Does this patient have a simple "black eye," or is this a fracture of the anterior cranial fossa of the skull? What role does the orbital septum play in enabling one to distinguish between these lesions? Is the appearance of the conjunctival hemorrhage important in making the diagnosis?

Question 5

A 6-month-old girl was seen in the emergency department because her mother had noticed a yellow, sticky discharge from the baby's left eye. On questioning, the mother said that she had first noticed the condition that morning when her daughter woke up. She also said that she had noticed that her daughter's left eye watered excessively when she cried ever since birth. The physician confirmed the epiphora of the left eye and noted the emergence of yellow pus into the lacus lacrimalis from the puncta when gentle pressure was exerted over the medial palpebral ligament. What is the diagnosis? What is the most likely cause in a child of this age? What are the posterior relations of the medial palpebral ligament? Describe the anatomy of the drainage passages of the conjunctival sac and give the direction of each of the tubes.

Question 6

A 7-year-old boy with right-sided otitis media was treated with antibiotics. The organisms did not respond to the treatment, and the infection spread to the mastoid antrum and the mastoid air cells. The surgeon decided to perform a radical mastoid operation. After the operation, it was noticed that the boy's face was distorted.

-The following signs and symptoms suggest that the right facial nerve had been damaged during the operation except which?

A) The mouth was drawn upward to the right.
B) He was unable to close his right eye.
C) Saliva tended to accumulate in his right cheek.
D) The saliva tended to dribble from the corner of his mouth.
E) All the muscles of the right side of his face were paralyzed.

Question 7

A 3-year-old boy was playing with his friend when they decided to see how many peas they could stick into each others ears. Later, the babysitter noticed that one of the boys had become completely deaf in his left ear. On examination in the emergency department of the local hospital, the physician's assistant noticed what appeared to be several peas deeply embedded in the left external auditory meatus. She decided to attempt the removal of the peas through an otoscope. Which direction should the auricle be pulled in a child to straighten the meatus and assist in the operation? How does this change in the adult?

Question 8

Following a severe cold, a 10-year-old girl complained of severe right-sided earache. On examination by her pediatrician, the tympanic membrane looked reddened and bulged laterally. A diagnosis of otitis media was made. A yellowish area was apparent close to the umbo and it appeared that perforation of the tympanic membrane was about to take place. It was decided to do a myringotomy (incise the tympanic membrane). Where would you do a myringotomy? What structures do you have to avoid in this operation? What are the features normally seen on the tympanic membrane with an otoscope?

Question 9

A 13-year-old boy was struck on his right ear by another boy's fist during a fight. By the time the boy was examined, the ear was extremely swollen and bluish and very painful. Explain in anatomic terms where the blood and edema fluid collect in such a case. Can the ear be treated conservatively or should the hematoma be drained? What is a cauliflower ear?

Question 10

A 45-year-old woman with a severe cold had to make a business trip by plane. On takeoff she noticed that her hearing became impaired and she experienced acute pain in her right ear. She told the stewardess about her problem and asked for an aspirin. The stewardess advised the patient to relax and swallow hard several times. On reaching the cruising altitude the right ear suddenly popped and the deafness and pain disappeared. In anatomic terms explain this patient's condition.