EAR 1 Anatomy

Ear 1: ANATOMYEar 1: ANATOMYJaved shah,

MBBS,DLO,FRCS Bannu Medical College

1. External Ear: Auricle,External Auditory Meatus, TM. a/Auricle, development:First Branchial cleft(EAM),1+5 tubercle.Tragus(1st arch)Rest of pinna 2nd arch.clinical preauricular sinus.Ear lobule?yellow elastic cartilage? tragus and rest of pinna.. End aural incision.grafts: middle ear surgery, septal and rhinoplasty.

External Auditory Meatus:First branchial cleft, length 24 cm. not straight, direction, cartilaginous part 1/3rd ,8mm. skin thick, glands,hairs.. furncles,Bony part:2/3rd (16mm),no hairs or glands but thin skin.isthmus,6mm lateral to TMthin bone separates from TM joint.

Tympanic Membrane(TM) a/Pars Tensa b/Pars Flaccida.TM has 3layers.a/outer epihelium..ectoderm.b/middle fibrous.mesoderm c/inner endoderm.Pars Tensa:outer edge fibrocartilaginous..annulus tympanicus.Umbo p/t at tip of malleus tented inward.cone of light, its importance in clinical practicePars Flaccida.malleolar folds,notch of rivinous.thin.3layers? layyers/

Disease of External Disease of External EarEar

Diseases of Pinna: congenital,Traumatic,inflammatorycongenital: Bat Ears(Lop Ears)defect concha is largeantihelix is poorly developed, treatment: surgery

Pre auricular appendages:skin covered tags,appear on line from tragus to angle of mouth.

Anotia: part of first arch syndrome MacrotiaMicrotia: associated with anomalies of EAM,middle and inner ear, hearing loss is frequent

Inflammatory:1/ Perichondritis.infection secondry to lacerations,haematoma and surgical incisions,psedomonas, treatment, antibiotic for long duration2/ Relapsing polychondritis:autoimmune,affecting laryngeal,trachea,R/ steroids.Chondrodermititis nodularis, nodule on free border of helix,painful R/excision with cartilage’

Trauma to the Auricle: a/haematoma of auricle..(collection of blood between cartilage and perichondrium)..cauliform ear.treatment: aspiration.incision and drainage.aseptic condition,prophylactic antibiotics .

b/Lacerations; to be repaired in 2 layers,perichondrium and skin,prophylactic antibiotics.c/Avulsion of pinna:partial and complete. repairedd/ frostbite;.oedema and erythema,bullae formation,necrosis,treatment, rewarming 38-42 c,analgesics,antibiotics

Keloid: trauma ..surgical,ornament.usual sites..ear lobule,helixtreatment..surgical excision..Recurrence is commonsteroids,low dose radiation(600-800 rads)just to mention.

Diseases of EAM:a/congenital,b/trauma c/inflammationd/tumours e/ miscellaneous.1/Atresia of EAM,2/ collaural fistula,

Otitis externaOtitis externaBacterial: localised(furuncle),diffuse OE,malignantOEFungal: otomycosisviral,herpes zoster otticus,otitus externa haemorragicaReactive: eczematous, seborrhoeic,neurodermatitis.

Furuncle,styphlococcal infection of hair follicle, causative factors. climate,scratching,or daibetic patient.severe pain?swelling EAM, serous discharge.resolves or chronic with meatal narrowing due thichening of meatal skin.R/ analgesia, suction and insertion of pop wick and ear drops,flucloxacillin as antibiotic.

Diffuse otitis externa: diffuse inflammation of EAM,and epidermal layer of TM.loss of retroauricular sulcus?cause, trauma,climate, systemic illness: diabetic.organism: staph, pseudomonas,proteus, Ecoli.R/Aural toilet,pop wick, antibiotics, 10% icthomol in glycerine?,analgesia,MeatoplastyD/D: mastoiditis,by exclusion and radiology if EAM swollen and TM cant be seen.(difficult situation)

Otomycosis: fungal infection of ear canal,organisms: aspergillus niger,A fumigatus,candida albicans.etiology, climate and secondry to over use of antibiotic era drops or discharging ear.symptoms, itching, musty odour discharge,fungal mass in ear canal appear white with black spots.R/ suctin clearance, antifungal (nystatin) and repeated suction.

Malignant (necrotising )otitis externa.elderly daibetics, or immunosupresed.peudomonas,Excruciating pain and resistant to RProgressive to ant/inf/skull base and multiple nerve palsy. high mortality.treatment, aminoglycoside, metronidazole, for long duration, surgery, not encouraged,

Herpes zoster outicus,(Ramsey hunt syndrome)viral infection of posterior root ganglion and vesicles on the external ear,distribution of cutaneous sensory nerve.1/herpes auricularis,2/herpes auricularis with facial nerve palsy3/ hepes auricularis with facial nerve palsy and 8th nerve with auditory symptoms,daefness and problems with balance

Keratosis Obturans:collection of desquamited epithelium in EAM,like white mass.migration of meatal epithelium this process hampered?this mass of keratin cause widening of meatus and absorpion of bone.treatment; removel of this mass a/suction and instruments in clinic,b/ if impacted under GA.

Foreign bodies in EAMnon living.piece of paper, cotton, broken end of match stick,vegetables method of removel: forceps, syringing, suction, GA post aural approach.living: insects, cockroache,maggotsR/ instilling olive or turpentine oil to kill the insector and then remove

Nerve supply of EAM:1/ Greater auricular(C2,3) ,lesser occipital nerve,(C2)Auricular branch of vagus,auriculotemporal 5th cr nerve

Important questions for Final MBBS exam.1/Define furuncle,sign and symptoms,D/D,treatment.2/ Ramsay Hunt syndrome,3/ Keratosis obturan4/ Reapsing perichondritus5/ nerve suppy of Pinna(EAM)