Botulinum toxin in Ophthalmic Practice Dr Sunayana Bhat Consultant Paediatric ophthalmology , Strabismus and Neuro ophthalmology Vasan eye care , Mangalore Ph : 9611102754chanyn9@gmail.com

Botulinum toxin injections are the fastest-growing cosmetic procedure all over the world

• Neurotoxin : Bacterium “Clostridium botulinum” • 'botulus' sausage German physician who described the poisoning after the ingestion of sausage.

• Mechanism of action • Activity and dosing• Clinically available forms • Uses • Complications

Mechanism of action • Heavy chain of 100 kDa • Light chain of 50 kDa 150 kDa core type A molecule

Mechanism of action ENDOCYTOSIS

SUBSTRATE MODIFICATION

Mechanism of action • Differ in SNARE protein / cleavage site A,B,C,D,E,F

PROCESS OF FUNCTIONAL RECOVERY

Sprouting of nerve fibers from the terminal axons Extra junctional Ach receptors

Activity and Dosing• 1 unit : LD50 female swiss webster mice , intra peritoneal

injection • 1 unit : 0.05 ng of toxin

• Stored dry • Reconstitution with saline 5-10 u : 0.1 ml

Commercial Preparations

Benign Essential Blepharospasm• Functional blindness : Episodic Spasms • Effective in 75%• 2.5 u each site …

• Subcutaneous • Sites :

Stabismus : Muscle Inj • Post paralytic ( prevent contractures )• With transpositions : for horizontals • Dysthyroid orbitopathy • Surgical surprises !• Infantile ET ??? Buying time

Nystagmus / Oscillopsia

The "ideal" patient for retrobulbar Botox -restricted movement -oscillopsia, -willing to use only one eye.

Chronic Dry Eyes Medial orbicularis muscle : inj

failed lacrimal pump

Subjective improvement of symptoms in 70% of cases

Post Peripheral Facial Nerve Synkinesis • Facial deformity• Drooling• Twitching / muscle spasms

Tics,Tremors and Myokymia• Spontaneous discharges• Known to resolve spontaneously

2.5 u

Elevated IOP due to Restrictive Myopathy

Corneal Protective Ptosis

Direct infiltration of levator muscle

Headache Syndromes

50 – 100 u

Eyelid diseases • Retraction grave’s disease

• Spastic Entropion Pre tarsal orbicularis overides- Ocular sx- Irritation

Compressive Optic Neuropathy • Enlarged muscles : crowding

• Reduced contraction • Reduced muscle bulk

Hyperhydrosis Lacrimal Hypersecretion syndromes • 1% population • Face , axilla , palms

• Frey syndrome : gustatory sweating

• Gustatory epiphora 2.5 U palpebral lobe of lacrimal gland8 mm of schirmer value reduction

Aesthetic uses • Forehead furrows• Glabellar lines • Lateral rhytides ( crows feet )• Brow lift • Perioral rhytides ( smokers lines )• Mesolabial folds (marionette lines )• Platysmal bands

ALL

IS

WELL………….

Complications • Ptosis - always transient• Induced deviations - usually transient• Diplopia - transient• Dilated pupil - rare• Reduced accommodation - rare• Scleral perforation* - rare - potentially serious• Lip droop - very bothersome; may be persistent

Future Trends • Antibody development ….

• Complication : anti globulin within 4 hrs

• Bioterrorism ……VACCINES ????.....

Thank u