cyclic oculomotor spasm

Question 1

what are the characteristics of celiac oculomotor spasm

Answer 1

Rare disorder
Involuntary, transient spasms of extraocular muscles (EOM)
Typically induced by sustained gaze
Cause intermittent diplopia
Affect EOM supplied by III, IV or VI cranial nerve
Majority have history of parasellar tumour and undergone radiation therapy
Remainder no known cause

Question 2

what is ocular neuromoyontonia

Answer 2

Ocular neuromyotonia (ONM) is a rare neurological disorder that affects the muscles that control eye movement. It is characterized by episodes of involuntary eye movement or double vision (diplopia) that occur intermittently and can last from seconds to minutes. ONM typically affects one eye, but it can affect both eyes in some cases.

ONM is caused by a malfunction in the communication between the nerves and muscles that control eye movement. This malfunction can lead to involuntary contractions or spasms of the eye muscles, causing the eye to move in an abnormal way. The exact cause of ONM is not fully understood, but it is thought to be related to damage or injury to the nerves that control eye movement.

Symptoms of ONM may include eye twitching, eye movement that is out of sync with the other eye, double vision, and difficulty focusing. These symptoms can be triggered by certain activities, such as reading or looking at a computer screen for an extended period of time.

Treatment for ONM may involve the use of medications that help to reduce muscle spasms or surgery to correct the underlying nerve damage. In some cases, the symptoms of ONM may improve on their own over time. It is important to consult with a healthcare provider if you are experiencing any symptoms of ONM.

Question 3

give an example of ocular myotonia

Answer 3

Left oculomotor ocular neuromyotonia.The primary position was characterized by orthotropia (a). Following 30s of right eccentric gaze (b), the patient developed involuntary contraction of left medial rectus, which resulted in left esotropia while returning both eyes to the primary position (c). The left esotropia lasted approximately 2min, then spontaneously resolved (d)

Question 4

what is the treatment for ocular myotonia

Answer 4

Medical - carbamazepine 200mg reduces frequency of attacks

Question 5

what to case reports suggest it can be caused by

Answer 5

tumours

acromegaly - body produces too much growth hormone
achoal

Question 6

what is superior oblique myotonia

Answer 6

Recurrent episodes of fine rapid eye movement causing vertical and torsional eye movements
Microtremor an intorsion - best observed on slit-lamp
Hypotropia
Can follow a superior oblique palsy
Patient aware of oscillopsia ‘funny sensation’ and diplopia
May be triggered by reading, fatigue, stress or occur spontaneously

Question 7

what is the aetiology of superior oblique myokimia

Answer 7

May present following head or ocular trauma or after brainstem tumour (rare)
Also been linked to neurovascular compression syndromes

Question 8

what is the treatment for superior oblique myokimia

Answer 8

Medication
Beta blockers (e.g. propranolol)
Carbamazepine
Surgery
Superior oblique tenectomy/ tenotomy
cause iatrogenic SO palsy and require ipsilateral IR recession
Symptoms can recur
SO tenotomy & IO myectomy
Partial weakening of SO tendon
Botulinum Toxin injection (Superior oblique) – often affect other EOM’s as well

Question 9

give an example of what someone with superior oblique myokymia would present with

Answer 9

53 year old female
Several years history of episodic twitching of her RE

Observation: Rythmic downbeating and intorting movements
Diagnosis: Superior Oblique Myokymia

Question 10

what is a cyclic oculomotor spasm

Answer 10

Rare non-progressive condition
Muscles innervated by the III cranial nerve undergo alternating rhythmic spasm and paralysis
-brief spasms of III nerve function alternates with complete or Partial III nerve palsy
Usually presents in infancy but cases are described in adults
Cycle can consist of periods of ptosis and mydriasis alternating with eyelid retraction with miosis (Yazici, 2000).
Possible lesion in region of supraclinoid

Question 11

what are the two phases of cyclic oculomotor phase

Answer 11

paretic phase and spastic phase

Paretic phase
III nerve palsy - ptosis, dilated pupil (mydriasis), reduced accommodation, exotropia/hypotropia
Spastic phase
Every 2-3 minutes – lasts 10-30 secs
Ptotic lid elevates, pupil constricts (miosis), esotropia