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Botulinum toxin in Ophthalmic Practice Dr Sunayana Bhat Consultant Paediatric ophthalmology , Strabismus and Neuro ophthalmology Vasan eye care , Mangalore Ph : 9611102754 [email protected] 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 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