Download Free Medical Congenital Hearing Loss PowerPoint Presentation

Congenital Hearing Loss PowerPoint Presentation

DOWNLOAD MEDICAL POWERPOINT PRESENTATION

About This Presentation

Description : Check out this medical presentation on Hearing Disorders, which is titled "Congenital Hearing Loss", to know about congenital hearing loss.

Tags : Hearing Disorders, Congenital Hearing Loss

Published on : Jul 10, 2021 | Views : 2708 | Downloads : 4

Shareable Url :

Embed Code :

Comment

Transcript

Slide 1-

Congenital Hearing Loss Ashley Starkweather, MD UCLA Head and Neck Surgery
Slide 2-

Etiology Congenital HL 50% Genetic 50% Acquired Childhood Onset HL 50% Genetic 25% Acquired 25% Unknown
Slide 3-

Genetic HL 75% non-syndromal 25% syndromal 75% autosomal recessive (AR) 25% autosomal dominant (AD) 1-2% X-linked Rare mitochondrial
Slide 4-

Autosomal recessive HL Monogenic, 25% risk to offspring if both parents are carriers Severe to profound SNHL, prelingual onset
Slide 5-

Autosomal recessive syndromal HL Usher syndrome Pendred Jervel and Lange Nielsen Goldenhar (Oculoauriculoverterbral spectrum)
Slide 6-

Usher Syndrome Retinitis pimentosa and SNHL Night blindness > field cut > central blindness Most common cause of congenital deafness Dx: electroretinography
Slide 7-

Usher Types Type I (most common): Profound SNHL, no vestibular fxn RP onset in early childhood Atypical myosin (myosin 7A): interferes with mechanoelectrical transduction in labyrinthine hair cells Type II: Congenital sloping SNHL Normal vestibular fxn RP onset in teens
Slide 8-

Usher Types Type III: Progressive SNHL and vestibular dysfunction Vestibulocerebellar ataxia Type IV: Mental retardation and hypotonia
Slide 9-

Usher
Slide 10-

Pendred Syndrome Defect in tyrosine iodination Gene mutation: affects pendrin, molecule involved in chloride-iodine transport Sx: severe to profound SNHL, multinodular goiter in childhood Assoc with Mondini malformation and enlarged vestibular aqueduct Dx: (+) perchlorate test Tx: thyroid hormone to suppress goiter
Slide 11-

Transverse CT scans of the middle ear in a 47-year-old patient with Pendred syndrome. (a) Modiolus is not discernible (short arrow). Vestibular aqueduct (arrowheads) and vestibule (long arrow) are enlarged. (b) Interscalar septum between upper and middle turn of the cochlea is absent (arrow).
Slide 12-

Jervell and Lange Nielsen Congenital profound SNHL Prolonged QT interval with syncope, sudden death Gene mutation: KVKQT1 = abnormal K+ channel Dx: EKG Tx: Beta blockers, hearing aids
Slide 13-

Goldenhar Syndrome First and second arch derivatives, hemifacial CHL and SNHL (mixed) Ocular: epibulbar dermoids, colobomas Auricular: preauricular appendages, pinna abnormalities, EAC atresia, ossicular malformation/absence, abnormal facial nerve, stapedius, semicircular canals and oval window Vertebral: fusion/absence of cervical vertebrae
Slide 14-

Goldenhar Syndrome
Slide 15-

Autosomal Dominant Vertical pattern of inheritance Risk to offspring of 50% if 1 parent affected Variable penetrance and expressivity Often postlingual hearing loss, progressive
Slide 16-

AD Syndromes Waardenburg Treacher Collins Apert Crouzon Stickler Neurofibromatosis Brancio-oto-renal
Slide 17-

Waardenburg Syndrome Abnormal tyrosine metabolism Pigment abnormalities: heterochromic iriditis, white forelock, patchy skin depigmentation Craniofacial abnormalities: dystopia canthorum, synophrys, flat nasal root
Slide 18-

Waardenburg Types Type I: Dystopia canthorum, pigment and craniofacial abnormalities, 20% with SNHL Mutation in PAX3 gene Type II: No dystopia canthorum, 50% with SNHL but not as severe MITF mutation
Slide 19-

Waardenburg Types Type III (most severe): Unilateral ptosis and skeletal abnormalities PAX3 mutation Type IV: Type II plus Hirschsprung’s disease (aganglionic megacolon)
Slide 20-

Treacher Collins (Mandibulofacial dysostosis) Hypoplasia of mandible and facial bones Downsloping palpebral fissures, colobomas Atretic external and middle ear Mixed HL Cleft palate (35%) Gene mutation on chr 5q: TCOF1 codes for a cell transport protein (treacle) Tx: BAHA, bone conduction HA, surgical correction of aural atresia
Slide 21-

Treacher Collins
Slide 22-

Apert Syndrome (Acrocephalosyndactyly) Middle and inner ear affected Stapes fixation (CHL), patent cochlear aqueduct, large subarcuate fossa Hand syndactyly, midface abnormalities, craniofacial dysostosis, trapezoid mouth
Slide 23-

Apert
Slide 24-

Crouzon Syndrome (craniofacial dysostosis) Atresia and stenosis of EAC, CHL, ossicular deformities Cranial synostosis, small maxilla, exophthalmos, parrot nose, short upper lip, mandibular prognathism, hypertelorism Abnormal FGF receptors
Slide 25-

Crouzon
Slide 26-

Stickler Syndrome Progressive Arthro-Ophthalmopathy Progressive SNHL (80%) Marfanoid body habitus Severe myopia, retinal detachment Flat midface Hypermobile joints Pierre Robin sequence: micrognathia, glossoptosis, cleft palate
Slide 27-

Neurofibromatosis NF-1 (Von Recklinghausen Disease) Café au lait spots, neurofibromas, Lisch nodules, 5% risk of unilateral acoustic neuroma NF-1 gene on Chr 17 NF-2 (central neurofibromatosis) Bilateral acoustic neuromas or unilateral with 1st degree relative with NF-2 or multiple central schwannomas NF-2 gene Chr 22q12 (tumor suppressor gene mutation)
Slide 28-

NF-1
Slide 29-

Branchio-oto-renal (Melnick Fraser Syndrome) Renal abnormalities: mild hypoplasia to bilateral aplasia Branchial cleft cyts Preauricular pits EYA1 on Chr 8q13 Hearing loss: Penetrance: 80% Mixed: 50% Conductive: 30% SNHL: 20%
Slide 30-

X-linked Disorders Alport’s syndrome Otopalatal-digital Norrie syndrome
Slide 31-

Alport’s Syndrome X-linked 80%, autosomal dominant 20% Progressive glomerulonephritis and SNHL Abnormal type IV collagen in GBM; gene COL4A5
Slide 32-

Alport’s Syndrome Bilateral degeneration of organ of Corti and stria vascularis Ocular disorders (myopia, cataracts) Dx: UA, BUN, Cr Tx: dialysis, renal transplant
Slide 33-

Otopalatal-digital Ossicular malformation (CHL) Palate defects Digital abnormalities: broad fingers and toes Hypertelorism, short stature, mental retardation
Slide 34-

Otopalatal-digital
Slide 35-

Norrie Syndrome Blindness Progressive mental retardation Hearing loss
Slide 36-

Mitochondrial Disorders Follows maternal line Postlingual HL Associated with systemic metabolic disorders Increased sensitivity to aminoglycoside ototoxicity Ex: MELAS: mitochondrial encephalopath, lactic acidosis, and strokelike syndrome MIDD: maternally inherited diabetes and deafness
Slide 37-

Acquired Congenital HL Prenatal: infections, teratogens Perinatal: NICU admission Postnatal: infections, neoplasms
Slide 38-

Prenatal Infections TORCHS: Toxoplasmosis Rubella CMV HSV encephalitis Syphilis
Slide 39-

Rubella Cataracts, cardiac defects, HL Atrophy of Organ of Corti, thrombosis of stria vascularis, loss of hair cells, endolymphatic hydrops Anemia, metal retardation, LE deformities, microcephaly, thrombocytopenia Dx: culture virus from urine, throat or amniotic fluid; antirubella IgM
Slide 40-

CMV 1-2% of live births Only 10% have HL Hemolytic anemia, microcephaly, mental retardation, HSM, jaundice, cerebral calcifications Dx: serum anti-CMV IgM, intranuclear inclusions “owl eyes” in renal tubular cells on UA
Slide 41-

Syphilis Treponema pallidum crosses placenta Often fatal Hutchinson’s Triad: abnormal central incisors, interstitial keratitis, profound SNHL Dx: VDRL, FTA-ABS, audiogram Tx: long term PCN, ampicillin, tetracycline or erythromycin; steroids for HL
Slide 42-

Prenatal Teratogens EtOH Thalidomide Radiation Aminoglycosides
Slide 43-

Perinatal Causes of HL Hypoxia Kernicterus Persistent fetal circulation
Slide 44-

Postnatal Causes of HL Meningitis (suppurative labryrinthitis) Ossification of labryinth Steroids help prevent HL Most common postnatal cause of HL Viral infection: mumps Ototoxins/Chemotherapy Trauma (acoustic, blunt, penetrating) Perilymph fistula Neoplasm: medulloblastoma, AN, fibrous dysplasia, histiocytosis) Autoimmune (rare in children)
Slide 45-

Inner Ear Dysmorphologies Michel’s aplasia Mondini aplasia Scheibe aplasia Alexander aplasia Bing Siebenmann Enlarged vestibular aqueduct Absence of CN VIII
Slide 46-

Michel’s aplasia AD or thalidomide exposure Complete aplasia of inner ear Anacusis, normal middle and outer ear Dx: CT shows hypoplastic petrous pyramid, absent cochlea and labyrinth
Slide 47-

Mondini Aplasia AD Most common cochlear abnormality Progressive or fluctuating HL  risk of perilymphatic gusher and meningitis from dilated cochlear aqueduct Dx: CT reveals single turned cochlea, no interscalar septum Tx: HA, cochlear implant
Slide 48-

ppt slide no 48 content not found
Slide 49-

Schiebe Aplasia AR Partial or complete aplasia of pars inferior (cochlea and saccule), normal pars superior (SCC and utricle) Defect of membranous labyrinth only, therefore can not diagnose on CT
Slide 50-

Alexander Aplasia AR Abnormal cochlear duct/ basal turn High frequency SNHL Cannot diagnose on CT
Slide 51-

Enlarged vestibular aqueduct Defined by diameter of duct >2mm at midpoint Progressive cochleovestibular loss No treatment
Slide 52-

Thanks for listening!
Slide 53-

Questions What % of patients with NF-1 have acoustic neuromas? 5% 20% 50% 95%
Slide 54-

What % of patients with NF-2 have acoustic neuromas? 5% 20% 50% 95%
Slide 55-

What is the basic defect that causes Alport syndrome? abnormal renal tubules abnormal collagen IV in glomerulus abnormal collagen I in glomerulus abnormal renal arteries
Slide 56-

What is the primary inheritance pattern for Alport’s syndrome?
Slide 57-

What syndrome does this patient have? Goldenhar Treacher Collins Crouzon Apert
Slide 58-

What inner ear aplasia will not allow for cochlear implants or amplification aids? Mondini aplasia Michel’s aplasia Enlarged vestibular aqueduct Alexander aplasia
Slide 59-

Which inner ear dyplasia is characterized by a lack of septae in the cochlea and only a basal turn? Mondini aplasia Michel’s aplasia Enlarged vestibular aqueduct Alexander aplasia
Slide 60-

What is the inheritance pattern of MIDD and MELAS?
Slide 61-

What abnormality is noted on this temporal bone CT?
Slide 62-

What genetic mutation is responsible for type I and III Waardenburg syndrome? COL2A1 Pendrin PAX3 Chr 22q12
Slide 63-

Thanks for listening!