Botulinum toxin in Ophthalmic Practice Dr Sunayana Bhat
Botulinum toxin in Ophthalmic Practice Dr Sunayana Bhat Consultant Paediatric ophthalmology , Strabismus and Neuro ophthalmology Vasan eye care , Mangalore Ph : 9611102754 chanyn 9@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 k. Da • Light chain of 50 k. Da 150 k. Da 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 : LD 50 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 Relaxation of corrugator ? Mechanism Nociceptive activity Frontalis Temporalis muscle on both sides Occipital muscle 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 gland 8 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
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