1. disorders of the innervation of pupils

Question 1

Causes of myadriasis

Answer 1

• Complete oculumotor nerve lesion
• Adies pupil (tonic pupil)
• Migraine
• Drugs

Question 2

Causes of miosis

Answer 2

• Horner syndrome
• Argyll-Robertson pupil
• Drugs

Question 3

Pupil innervation

Answer 3

Sympatetic: dilation
Parasympatetic: constriction

Question 4

Sympatetic innervation of pupil

Answer 4

• Innervation of dilator pupillae m.
• Dilates the pupil
• Response to decreased light or fight-or-flight-mode

Question 5

Parasympatethic innervation of pupil

Answer 5

• Oculumotor nerve (short ciliary nerves) innervating sphincter pupillae m.
• Constricts the pupil
• Part of accomodation-convergence reflex

Question 6

Lesion of symp. inn. of pupil

Answer 6

Horner-triad

Question 7

Lesion of parasymp. inn of pupil

Answer 7

Myadriasis

Question 8

Examination of intraocular muscles

Answer 8

• Size and shape
• Direct/indirect pupillary reflex
• Accomodation-convergence reflex

Question 9

Signs of complete oculumotor nerve lesion

Answer 9

• Myadriasis, ptosis, impaired eye movement on affected side
• Loss of direct pupillary reflex
• Loss of accomodation reaction

Question 10

Characteristics of Adies pupil

Answer 10

• Bilateral myadris
• Benign, young womem
• Acute onset

Question 11

Clinical features of Adies pupil

Answer 11

• Myadriasis
• Absent direct and indirect pupillary reflex
• May have reduced/absent limb reflexes (called Holmes-Adie syndrome)

Question 12

Drugs causing myadriasis

Answer 12

• Anticholinergic drugs
• TCA
• NSAIDS
• Antihistamines
• Oral contraceptives

Question 13

Location of damage in Horner’s syndrome

Answer 13

Sympathetic damage at:
- brainstem
- cervical cord
- cerv. symp. chain
- middle fossa
- int. carotid a.
- anterior roots of C8 and T1

Question 14

Etiology of Horner’s syndrome

Answer 14

• Tumor (pancoast)
• Vascular lesions
• Congenital (syringomyelia)

Question 15

How to distinguish between central and peripheral cause of Horner’s syndrome

Answer 15

If lesion is preganglionic, cocaine in eyes will still cause dilation

Question 16

Clinical features of Horner’s syndrome

Answer 16

• Ptosis (weakness of sup. and inf. tarsal muscles
• Miosis (weakness of dil. pupillae m.)
• Disturbance of sweating (depends on lesion site)

Question 17

Clinical features of Argyll-Robertson pupil

Answer 17

• Irregular shaped, small pupils not reacting to light
• Accomodation present
• Do not respond to pupillary dilator drugs
• Usually together with syphilis infection

Question 18

Drugs causing miosis

Answer 18

Parasympathomimetics:
- Direct acting (muscarinic receptor agonists, pilocarpine)
- Indirect acting (acetylcholinesterase inhibitors, neostigmine, rivastigmine)

Question 19

Other pupillary disorders

Answer 19

• Failure of accommodation and convergence
• Amaurotic pupil
• Marcus Gunn pupil
• Anisocoria

Question 20

Causes of failure of accommodation and convergence

Answer 20

• Extrapyramidal diseases (parkinosis)
• Pineal region tumors

Question 21

What is amaurotic pupil?

Answer 21

Absolute afferent pupillary defect
- lesions of the optic nerve
- direct and consensual light reflex cannot be elicited from affected side
- consensual light reflex can be elicited from normal side (intact oculomotor nerve

Question 22

Marcus Gunn pupil

Answer 22

Relative afferent pupillary defect
- impaired optic nerve causing decreased response to swinging-flaslight test

Question 23

Swinging-flashlight test

Answer 23

less constriction when bright light is swung from unaffected to affected side. The affected side still senses the light and produces constriction to some degree (but reduced)

Question 24

Anisocoria

Answer 24

Unequal pupil size. Fixed and dilated pupil indicates oculumotor lesion. May be caused by transtentorial herniationdue to space occupying lesions, compressing oculumotor nerve