Neurological Cases Studies

Anne E. Chauvet, DVM, DACVIM (Neurology)


For all questions below, please answer the following

Part A:  Where is the lesion?

Part B:  What are your top three (3) differential diagnoses?

            1.

            2.

            3.

Part C: What is your diagnostic plan?

Question #1:

A 3 month-old thoroughbred filly is presented to you for being down.  She was seen playing in pasture with other horses previously that day but was found down in the field two hours prior to presentation.  All other horses, foals and fillies are fine.  The physical examination indicates a rythmic change in respiratory rate.  Her temperature is 99 F.

Mentation, posture, gait:  

            Occasional thrashing around, stuporous to comatose;  opisthotonus is noted.  Tetraplegic, non ambulatory.

Cranial nerve examination:

            Mid range to dilated pupils, non responsive to light.  Physiologic nystagmus is decreased to absent.  There is no menace response or gag reflex present.

Proprioception:

            The filly cannot bear her own weight.  In a sling, she thrashes. 

Appendicular reflexes:

            All present

Pain evaluation:

            Normal.

Question #2:

A 3 year-old female spayed Labrador Retriever is presented to your clinic for sudden paraplegia that began with the left pelvic limb then the right pelvic limb12 hours prior to presentation.  The significant examination findings are limited to the neurologic system.

Mentation, posture, gait:  

            Paraplegia        

Cranial nerve examination:

            Normal

Proprioception:

             Absent conscious proprioception in the pelvic limbs.

Appendicular reflexes:

            Absent patellar reflexes, normal gastrocnemius and withdrawal reflexes.  Normal cutaneous trunci and perianal reflexes.

Pain evaluation:

            Deep pain present bilaterally.  No pain upon palpation of the spine.

Question #3:

A 7 year-old male intact Miniature Schnauzer is presented to you for progressive recumbency over the last 3 days.  The dog lives in the country and likes to kill opossums and raccoons.  All vaccines are up to date.  The findings are limited to the neurological examination.

Mentation, posture, gait:  

            Normal mentation.  Tetraparetic but ambulatory with support.  Very weak.

Cranial nerve examination:

            Slight decreased palpebral and menace responses.

Proprioception:

             Decreased conscious proprioception is noted in all four limbs.

Appendicular reflexes:

            The reflexes are significantly decreased. The cutaneous trunci reflex is absent bilaterally.

Pain evaluation:

            The dog cries easily when you evaluate the withdrawal and cutaneous trunci reflexes.

Question #4:

A 12 year old male neutered domestic-short-haired cat is presented for a one year history of recurrent lethargy responsive to steroids.  A week ago, he had one grand mal seizure.  The day prior to presentation, the cat had loss of balance and disorientation.  All abnormal findings are limited to the neurologic examination.

Mentation, posture, gait:  

            Moderate obtundation.  Severe ataxia of all four limbs and tetraparesis are noted.

Cranial nerve examination:

            Absent menace bilaterally. Vision is normal as assessed by tracking and pupillary light responses. Horizontal nystagmus with fast phase to the right is noted when sitting up.  When the cat is on his left side, the nystagmus is vertical in the right eye and horizontal  to the right in the left eye.

Proprioception:

             Conscious proprioception is absent in both pelvic limbs and decreased in the thoracic limbs.  Hopping is decreased in the pelvic limbs.  Visual and tactile placing are decreased.

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #5:

An 8 year-old female spayed Shih Tzu is presented with a two day history of seizures. She has been lethargic since. The physical examination and vital signs are normal.

Mentation, posture, gait:  

            Normal

Cranial nerve examination:

            Normal

Proprioception:

             Normal

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #6:

A one year old male neutered Golden Retriever is presented to you for a 1 week history of progressive generalized weakness.  Coughing and increased respiratory difficulty are noted over the last 2 days.  The physical examination reveals crackles in the cranioventral portion of the lung fields.  The rectal temperature is 103.8 F.

Mentation, posture, gait:  

            Alert and responsive.  Tetraparetic, non-ambulatory but when propped up, the dog can take a few steps with support.  Ataxia is not noted.

Cranial nerve examination:

            Normal

Proprioception:

            Conscious proprioception is decreased to absent in all four limbs

Appendicular reflexes:

            Patellar reflexes are decreased.  The biceps and triceps reflexes are not elicited.  The withdrawal reflexes appear slightly decreased but are present. Cutaneous trunci reflex is somewhat weak.

Pain evaluation:

            Normal.

Question #7:

A 6 year old male neutered Weimeraner is presented to you for a 2 months history of progressive cervical pain.  He holds his head  low and will not go up and down stairs anymore.  All abnormal findings are limited to the neurologic system.

Mentation, posture, gait:  

            Alert and responsive.  The gait is stiff and hesitant in the thoracic limbs and more fluid in the pelvic limbs.  Some ataxia is noted in the pelvic limbs.  Tetraparesis is mild.

Cranial nerve examination:

            Normal

Proprioception:

             The conscious proprioception is decreased in the pelvic limbs but normal in the thoracic limbs.

Appendicular reflexes:

            Normal

Pain evaluation:

            Severe pain is noted upon palpation and manipulation of the neck.  The cervical muscles are very tense, especially in the lower neck.

Question #8:

An 11 year-old male German Shepherd Dog is presented to you with a 6 months history of progressive pelvic limb weakness.  The dog has trouble getting in and out of the car as well as going up stairs.  The owner does not think the dog is painful. 

Mentation, posture, gait:  

            Mentation is normal.  The pelvic end is crouched low.  The dog is paraparetic, ambulatory and ataxic in the pelvic limbs.  The tail carriage is low.

Cranial nerve examination:

            Normal

Proprioception:

             Conscious proprioception is absent in the pelvic limbs.

Appendicular reflexes:

            The crossed extensor reflex is noted in the pelvic limbs.

Pain evaluation:

            No pain is palpated

Question #9:

A 6 year-old female spayed domestic short haired cat with progressive loss of balance for 3 weeks is presented to you.  The cat had been more lethargic  over the last 2 to 3 months.  Over the past two days, the patient has been falling and leaning to the right.  The owner reports that she also has had a hard time picking up her food and smashes her nose in her food.  When excited, her head sways side to side.

Mentation, posture, gait:  

            Alert and responsive.  Severe ataxia on all four limbs with leaning and falling to the right.  She circles to the right.  Dysmetria/hypermetria is noted on the left limbs, especially the thoracic one.

Cranial nerve examination:

            Menace is absent in the left eye.  Vision and palpebral reflexes are normal bilaterally.  Vertical nystagmus is noted in both eyes when the cat is on her back and a rotatory nystagmus to the right is noted when the cat is standing.

Proprioception:

             Visual placing is present in both thoracic limbs.  Tactile placing is absent in the left thoracic limb.  Conscious proprioception is decreased on the left side.

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #10:

You are called to a feedlot to look at a number of calves that are dying.  The owner has had a recent epidemic since he received a new shipment of calves about 4 weeks prior.  Ten calves are in isolation for respiratory distress.  About 5 calves are lame.  Over the last week two calves were found dead after seizures and head pressing episodes.  This morning, three more calves are demonstrating neurologic signs and seem blind.  The feed source has been constant as has the water supply.

Mentation, posture, gait:  

            The 3 calves examined are obtunded to varying degrees and are ataxic.  One calf is recumbent and opisthotonic with severe obtundation.  One other calf has a seizure during your visit. 

Cranial nerve examination:

            Menace and vision are absent in two of the three calves.

Proprioception:

             Not assessable.

Appendicular reflexes:

            Not assessable.

Pain evaluation:

            All three animals are very vocal but seem more demented than painful.

Question #11:

An 8 month-old male neutered Lasha Apso is presented for episodic weakness over the last two weeks.  The abnormalities are limited to the neurological examination.

Mentation, posture, gait:  

            Normal mentation.  The pup tires quickly with exercise and becomes hunched up and lame.  With cage rest, he recovers with a half hour.

Cranial nerve examination:

            Normal although the palpebral response is inconsistent.

Proprioception:

             Normal

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #12:

A 10 year old female spayed Labrador Retriever is presented for sudden loss of balance the night prior to presentation. You find out that this patient had a bout of diarrhea two weeks earlier and is currently treated with metronidazole (300 mg/kg 2 times a day).  This patient also receives L- levothyroxine twice daily.

Mentation, posture, gait:  

            Alert and responsive but rolling and leaning to the left.  The patient is unable to ambulate even with support due to loss of balance but she is very strong.  Increased extensor tone is noted on the right side. 

Cranial nerve examination:

            Non positional horizontal nystagmus to the right is noted.

Proprioception:

             Normal

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #13:

A 7 year old male English Toy Spaniel is presented to you for episodic disorientation, circling and placing deficits of a week duration.  The disorientation is worse 2 to 4 hours post prandial.  The owners also report seizures once or twice a month for the past 6 months.  The referral blood work indicates a normal CBC and chemistry.

Mentation, posture, gait:  

            Severe obtundation.  Stiff pelvic gait with some pelvic ataxia.

Cranial nerve examination:

            The pupillary light response is absent bilaterally but menace is present.  The pupils are dilated. 

Proprioception:

             Normal

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #14:

An 8 year-old male neutered Golden Retriever is presented to your clinic with a history of difficulty rising in the pelvic limb for 2 weeks.  The right pelvic limb was first affected then the left one.  Steroids have improved clinical signs.

Mentation, posture, gait:  

            Paraparetic and non-ambulatory, worse on the right.

Cranial nerve examination:

            Normal

Proprioception:

            Conscious proprioception is absent in the pelvic limbs

Appendicular reflexes:

            Normal

Pain evaluation:

            Severe pain upon palpation of the lumbosacral spine.

Question #15:

A 6 year old female spayed Beagle is presented with a history of recurrent back pain and hunched back over the past 18 months.  Two days prior to presentation, she began having another episode.  The clinical signs progressed to difficulty walking and then recumbency in the pelvic limbs.  Abnormalities are limited to the neurological examination.

Mentation, posture, gait:  

            Normal mentation.  Paraparesis but non-ambulatory.

Cranial nerve examination:

            Normal

Proprioception:

Absent proprioception in the pelvic limbs

Appendicular reflexes:

            Cutaneous trunci cut off at T12-13, bilaterally.

Pain evaluation:

            Pain is elicited upon palpation of the thoracolumbar spine.

Question #16:

A 3 year old ewe is brought to your clinic for circling.  The physical examination is unremarkable except for the neurological findings.

Mentation, posture, gait:  

            Moderate obtundation.  Circling to the left.  Hemiparesis on the left but still ambulatory.

Cranial nerve examination:

            The menace, palpebral and vibrissae reflexes are absent on the left side.  The corneal response is absent on the left.  Horizontal nystagmus is noted to the right, in all head positions.

Proprioception:

            Decreased conscious proprioception is noted on the left side only.  When hemiwalked, the sheep collapses on the left side.    

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #17:

A 3 year old female spayed domestic short haired cat is presented for seizures.  This cat was adopted one year prior and is FeLV and FIV negative.  The cat has had the right thoracic limb amputated due to trauma.  Six other cats are in the same household, all indoors only.  The cat is a known diabetic and is receiving Insulin twice a day.  The seizures have been noted for a week and are non responsive to valium and phenobarbital.  The cat is clustering at the time of presentation.

Mentation, posture, gait:  

            The cat is post-ictal, pacing, twitching at the face and weak.

Cranial nerve examination:

            Can not assess due to post ictal status.

Proprioception:

             Post ictal, therefore can not assess

Appendicular reflexes:

            Appear normal

Pain evaluation:

            Normal

Question #18:

A 7 year old female spayed Labrador Retriever presents to you for a 3 day history of progressive weakness in the thoracic limbs.  She became recumbent on all 4 limbs the night prior to presentation.  Steroids seem to be of little help.  The abnormal findings are limited to the neurological examination.

Mentation, posture, gait:  

            The mentation is normal.  The dog is paretic in the pelvic limbs and paralyzed in the thoracic limbs.  She is non-ambulatory.

Cranial nerve examination:

            The left pupil is small than the right pupil.

Proprioception:

            Absent on all four limbs.

Appendicular reflexes:

            All present.

Pain evaluation:

            Pain is noted upon palpation of the high cervical spine.

Question # 19:

A 6 year old gelded Thoroughbred is presented for muscle atrophy and weak pelvic limbs.  One week prior to the examination, the owner noted atrophy of the left masseter muscle.  Rapid muscle atrophy was noted in the right gluteal musle and in the right temporalis muscle as well.

Mentation, posture, gait:  

            The horse is alert and responsive.  The protraction phase of the right pelvic limb is delayed when walking.  The right pelvic limb is uncoordinated with the left and the horse steps on his right pelvic limb when turned to the right.

Cranial nerve examination:

            The muscle atrophy noted by the owner are recorded.

Proprioception:

            The horse will not adduct the right pelvic limb back in normal position, when abducted.

Appendicular reflexes:

            Not assessed in the horse.

Pain evaluation:

            Normal

Question #20:

A 2 year old male Great Dane is presented for abnormal gait.  The changes in gait have progressed over the past 3 months.  The vital signs and physical examination are normal.

Mentation, posture, gait:  

            Normal mentation.  When walking or trotting, the gait in the thoracic limbs is stiff and choppy.  Ataxia is noted in the thoracic limbs.  Mild paraparesis is noted.

Cranial nerve examination:

            Normal

Proprioception:

            Decreased proprioception is noted in the pelvic limbs.

Appendicular reflexes:

            Normal

Pain evaluation:

            When the neck is dorsoflexed or ventroflexed, the dog sits or collapses.  The dog is only resistant to lateral flexion of the neck is pressure is placed on the lower cervical spine.

Question #21:

A 9 year-old male neutered Springer Spaniel is presented for lameness of the right thoracic limb.  The first signs of lameness were noted about 3 weeks ago and have progressed to lameness in the right pelvic limb as well.  The vital signs are normal but the respiratory rate is high.

Mentation, posture, gait:  

            Normal mentation.  The dog is paraparetic, ambulatory. and holds the right thoracic limb up.  He scuffs in the right thoracic and pelvic limbs.  Ataxia is noted in the pelvic limbs

Cranial nerve examination:

            The right pupil is smaller in size than the left but both are responsive to light.  The right third eyelid is slightly prolapsed and the orbital fissure is smaller on the right.

Proprioception:

            Conscious proprioception is absent in the right thoracic and pelvic limb and decreased in the left pelvic limb.  Hopping is absent in the right thoracic limb.

Appendicular reflexes:

            The right triceps reflex can not be elicited/is absent.  The biceps reflex is present on both sides.  Withdrawal response is decreased in the right thoracic limb.  When you pinch the skin, on either side and at any level, to assess the cutaneous trunci response,

the right side does not contract.

Pain evaluation:

            Some pain is elicited upon manipulation of the right thoracic limb but you can not localize it.  The right triceps muscle group appears atrophied compared to the left side.

Question #22:

A 5 year-old male neutered domestic long haired cat is presented for plantigrade gait in the pelvic limbs.  The gait was first noted to be abnormal about 1 week prior to presentation.  The cat is reluctant to jump heights now.  The owner has also reported urinary accidents in the house.  The urine appears pinkish.  On physical examination, the cat is obese.  The only other abnormalities are limited to the neurological examination.

Mentation, posture, gait:  

            Normal mentation.  The cat seems to prefer to sit.  The gait is plantigrade in the pelvic limbs. 

Cranial nerve examination:

            Normal

Proprioception:

            Normal although occasionally, the proprioception is decreased in the pelvic limbs.

Appendicular reflexes:

            The withdrawal and gastrocnemius reflexes are decreased in the pelvic limbs.  The cutaneous trunci reflex is present but weaker.  The tail carriage is normal as are all pudendal reflexes. 

Pain evaluation:

            Normal

Question #23:

A 12 year old female Boxer cross dog is presented for masticatory muscle atrophy.  The owners have noted the atrophy of the left temporalis and masseter muscle over the last 2 weeks.  Two days ago, the dog began having difficulty chewing/eating.  The only abnormalities are limited to the neurological examination.

Mentation, posture, gait:  

            The dog is slightly obtunded but still reponsive to praise.  The gait is slightly hemiparetic on the left and ataxic on turns.  The stance is broad base.

Cranial nerve examination:

            The left pupil is dilated and non responsive to light.  Menace and tracking is absent on the left side.  The palpebral and vibrissae reflex are absent on the left side.  Physiologic nystagmus is absent in the left eye and the eye is more sunken in on the left side resulting in  prolapsed third eyelid and smaller fissure on that side.  The corneal reflex is absent on the left.  The gag response is present but decreased.  Excessive drooling is noted on the left side and the masticatory muscles are severely atrophied.   The dogís head is tilted to the left and vertical nystagmus is noted in the right eye.  The tongue is deviated to the right and the dog can not lick the left upper lip.

Proprioception:

            Conscious proprioception is severely decreased on the left thoracic and pelvic limbs.

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal although the dog resists upper cervical lateral flexion on either side and tends to hold the head straight out.

Question #24:

A 2 year-old Thoroughbred colt is presented for abnormal gait, progressive over the past 2 months.  His performance in training declined since to the point that he stumbles frequently and has been pulled out of training.

Mentation, posture, gait:  

            The mentation is normal.  The colt is ataxic, more so in the pelvic limbs.  He stumbles in turns and steps on his hooves repeatedly.  When blindfolded, his ataxia is worse and his stance is broad base.  The colt is weak especially with back pressure.

Cranial nerve examination:

            Normal

Proprioception:

            Severely impaired placing on all four limbs, worse pelvic.

Appendicular reflexes:

            Not assessed except for cutaneous trunci which is normal

Pain evaluation:

            Normal

Question # 25:

A 4 year old mare is presented for sweating behind the ear and difficulty swallowing.  She also has had increased attempts to swallow.  Nasal discharge is noted on the left side.

Mentation, posture, gait:  

            Mentation, gait and posture are normal

Cranial nerve examination:

            The left pupil is smaller than the right one but both respond to light and both eyes are visual.  Sweating is noted in the distribution of C1-2 skin innervation on the left side.  The slap test which assesses swallowing is decreased on the left. 

Proprioception:

            Normal

Appendicular reflexes:

            Not assessed in the horse.

Pain evaluation:

            Normal

Question #26:

An 8 year-old female mixed breed farm dog is presented for urinary incontinence of sudden onset.  The only abnormalities noted are in the neurological examination.

Mentation, posture, gait:  

            The tail is flaccid.  The gait is normal

Cranial nerve examination:

            Normal

Proprioception:

            Normal

Appendicular reflexes:

            The limb reflexes are normal. The anus is gaping open and the perianal reflex is absent.   Urine is leaking constantly and minimal abdominal pressure results in a large amount of urine voiding.  The tail is flaccid.

Pain evaluation:

            No pain on palpation.  Deep pain is present in the tail.  The cutaneous sensation perianally is absent.

Question #27:

A 4 year old male neutered mixed breed dog is presented for lameness in the right thoracic limb.  The lameness started 6 months ago and worsened since.  All orthopedic examinations were non rewarding. All abnormal findings are limited to the neurologic examination.  The orthopedic examination in the examination room is normal.

Mentation, posture, gait:  

            Normal mentation.  The dog is lame in the right thoracic limb and holding the limb up. 

Cranial nerve examination:

            Normal

Proprioception:

            Conscious proprioception is normal in all limbs but the right thoracic limb.  The dog will not place the right thoracic limb down.

Appendicular reflexes:

            The biceps and triceps reflexes are absent in the right thoracic limb.  The withdrawal response is decreased in the right thoracic limb.  The cutaneous trunci motor reflex is absent on the right.

Pain evaluation:

            Normal on palpation.  The cutaneous sensory testing reveals loss of sensation in the limb up to the elbow.

Question #28:

A 10 year old female spayed Miniature Poodle is presented with a  10 week history of altered mentation and seizures.  The owners report that she does not know where her food is and has to turn in circles a number of times before she finds it.  The physical examination is normal except for the neurological examination.

Mentation, posture, gait:  

            The dog is severely obtunded.  She paces constantly and walks in large circles to the right.  She is not ataxic.

Cranial nerve examination:

            The dog does not tract to the left side although the menace is normal on that side.  The dog tries to bite when you pinch the right upper lip but ignores the left lip pinch.  She does not respond to auditory stimuli on the left.

Proprioception:

            Conscious proprioception is absent on the left thoracic and pelvic limb and decreased on the right side.

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal on palpation.  When you pinch the dog on the right side, she turns promptly to that side but ignores pinches on the left side.

Question #29:

A 5 year old male domestic short haired cat is presented to you for a 3 days progressive onset of tremors.  On examination the rectal temperature is 103.5 F.  The abdomen is slightly enlarged. 

Mentation, posture, gait:  

            The catís mentation is slightly obtunded.  He tends to lean and fall to the right.  Whole body tremors are noted.  The head bobs when the cat attempts to focus its attention on an object.   The gait is hypermetric on both thoracic limbs mostly.  The stance is broad base.

Cranial nerve examination:

            The menace is absent bilaterally but tracting and pupillary light response are intact as well as palpebral reflexes.

Proprioception:

            Normal

Appendicular reflexes:

            Normal

Pain evaluation:

            Normal

Question #30:

You are called to a pig farm to see a 2 year old breeding male that was found down that morning.  All other pigs are normal.  All pigs are on the same feed and water.  The males are housed separately.

Mentation, posture, gait:  

            Normal mentation.  Paraparesis non ambulatory.

Cranial nerve examination:

            Normal

Proprioception:

            You can not stand this large pig to assess its proprioception.

Appendicular reflexes:

            The withdrawal is brisk in both pelvic limbs.  You can not assess the other reflexes.  The tail tone is excellent.  The anus is not gaping open.

Pain evaluation:

            Normal sensation and no pain on palpation of the spine.