Presentation on theme: "Botulinum toxin in Ophthalmic Practice Dr Sunayana Bhat Consultant Paediatric ophthalmology, Strabismus and Neuro ophthalmology Vasan eye care, Mangalore."— Presentation transcript:
Botulinum toxin in Ophthalmic Practice Dr Sunayana Bhat Consultant Paediatric ophthalmology, Strabismus and Neuro ophthalmology Vasan eye care, Mangalore Ph :
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
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
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