Sensory - Hearing Abnormalities

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Newborn hearing test

How and why do things go wrong in development? Developing of hearing requires a complex origin, organisation, and timecourse means that abnormal development of any one system can impact upon the development of hearing. There are many different abnormalities of hearing development that can result in hearing loss and can broadly be divided into either conductive or sensorineural loss. These abnormalities can have genetic, environmental or unknown origins. In addition, abnormalities of the external ear (position and structure) is used as a clinical diagnostic tool for developmental abnormalities in other systems.

In Australia, there is now an early postnatal screening of neonatal hearing as part of a NSW State Wide Infant Screening Hearing (SWISH) Program using Automated Auditory Brainstem Response (AABR).

Many environmental factors during development can lead to hearing abnormalities. A pregnancy Rubella viral infection example may cause deafness associated with congenital rubella syndrome.

Hearing Links: Introduction | Science Lecture | Medicine Lecture | Inner Ear | Middle Ear | Outer Ear | Balance | Hearing - Neural Pathway | Stage 22 | Abnormalities | Neonatal Diagnosis - Hearing | Hearing test | Sensory Introduction | Placodes | Student project | Category:Hearing
Historic Embryology 
Historic Embryology: 1902 Development of Hearing | 1906 Membranous Labyrinth | 1913 Tectorial Membrane | 1918 Human Embryo Otic Capsule | 1918 Cochlea | 1918 Grays Anatomy | 1922 Human Auricle | 1922 Otic Primordia | 1931 Internal Ear Scalae | 1933 Endolymphatic Sac | 1934 Otic Vesicle | 1934 Membranous Labyrinth | 1963 Human Otocyst | Historic Disclaimer

Abnormality Links: Introduction | Genetic | Environmental | Unknown | Teratogens | Cardiovascular | Coelomic Cavity | Endocrine | Gastrointestinal Tract | Genital | Head | Integumentary | Musculoskeletal | Limb | Neural | Neural Crest | Renal | Respiratory | Placenta | Sensory | Hearing | Vision | Twinning | Developmental Origins of Health and Disease | ICD-10
Historic Embryology  
1915 Congenital Cardiac Disease | 1917 Frequency of Anomalies in Human Embryos | 1920 Hydatiform Degeneration Tubal Pregnancy | 1921 Anencephalic Embryo

Some Recent Findings

  • Tmc gene therapy restores auditory function in deaf mice[1] "Genetic hearing loss accounts for up to 50% of prelingual deafness worldwide, yet there are no biologic treatments currently available. To investigate gene therapy as a potential biologic strategy for restoration of auditory function in patients with genetic hearing loss, we tested a gene augmentation approach in mouse models of genetic deafness. We focused on DFNB7/11 and DFNA36, which are autosomal recessive and dominant deafnesses, respectively, caused by mutations in transmembrane channel-like 1 (TMC1). Mice that carry targeted deletion of Tmc1 or a dominant Tmc1 point mutation, known as Beethoven, are good models for human DFNB7/11 and DFNA36. We screened several adeno-associated viral (AAV) serotypes and promoters and identified AAV2/1 and the chicken β-actin (Cba) promoter as an efficient combination for driving the expression of exogenous Tmc1 in inner hair cells in vivo. Exogenous Tmc1 or its closely related ortholog, Tmc2, were capable of restoring sensory transduction, auditory brainstem responses, and acoustic startle reflexes in otherwise deaf mice, suggesting that gene augmentation with Tmc1 or Tmc2 is well suited for further development as a strategy for restoration of auditory function in deaf patients who carry TMC1 mutations." OMIM TMC1 9q21.13
  • Human fetal inner ear involvement in congenital cytomegalovirus infection[2] "Congenital cytomegalovirus (CMV) infection is a leading cause of sensorineural hearing loss (SNHL). ...CMV-infection of the marginal cell layer of the stria vascularis may alter potassium and ion circulation, dissipating the endocochlear potential with consequent SNHL. Although abnormal cerebral ultrasound is highly predictive of brain and inner ear damage, normal ultrasound findings cannot exclude them either." Cytomegalovirus
  • Multicenter newborn hearing screening project[3] "From the actual point of view, the "sensitive period" for the effects of hearing impairment on speech and language development is within the first year of life. Early exposure to acoustic or electric stimulation can compensate for the acoustic deficit. A regional-based, specifically designed concept of a universal newborn hearing screening (UNHS) was started in Hamburg in the year 2002. ...Sixty-three thousand, four hundred fifty-nine out of 65,466 births were registered during the period August 2002 to July 2006, 93% were primarily screened. 3.3% failed the test and 31.3% were lost to follow-up. A total of 118 children were diagnosed with hearing loss in the follow-up."
  • Review - The etiology of otosclerosis[4] "Otosclerosis is a common form of hearing loss characterized by abnormal bone remodeling in the otic capsule. It is a complex genetic disease, caused by a combination of genetic and environmental factors. During the past decade, several attempts have been made to identify factors for otosclerosis."
  • Ototoxic drugs: difference in sensitivity between mice and guinea pigs.[5] "These results indicate that the mouse is not a good model for ototoxicity, which should be taken into consideration in all further investigations concerning ototoxicity-induced hearing loss."
More recent papers
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Search term: Abnormal Development Hearing

Beata Aleksiūnienė, Rugilė Matulevičiūtė, Aušra Matulevičienė, Birutė Burnytė, Natalija Krasovskaja, Laima Ambrozaitytė, Violeta Mikštienė, Vaidas Dirsė, Algirdas Utkus, Vaidutis Kučinskas Opposite chromosome constitutions due to a familial translocation t(1;21)(q43;q22) in 2 cousins with development delay and congenital anomalies: A case report. Medicine (Baltimore): 2017, 96(16);e6521 PubMed 28422838

Vijayalakshmi Easwar, Hiroshi Yamazaki, Michael Deighton, Blake Papsin, Karen Gordon Simultaneous bilateral cochlear implants: Developmental advances do not yet achieve normal cortical processing. Brain Behav: 2017, 7(4);e00638 PubMed 28413698

Antonietta Giannattasio, Pasquale Di Costanzo, Paola Milite, Daniela De Martino, Eleonora Capone, Antonia Romano, Carmela Bravaccio, Letizia Capasso, Francesco Raimondi Is lenticulostriated vasculopathy an unfavorable prognostic finding in infants with congenital cytomegalovirus infection? J. Clin. Virol.: 2017, 91;31-35 PubMed 28412596

Haoxing Jin, Gail J Demmler-Harrison, David K Coats, Evelyn A Paysse, Amit Bhatt, Jane C Edmond, Kimberly G Yen, Paul Steinkuller, Jerry Miller, Congenital CMV Longitudinal Study Group Long-term Visual and Ocular Sequelae in Patients with Congenital Cytomegalovirus Infection. Pediatr. Infect. Dis. J.: 2017; PubMed 28399055

Megan R Reynolds, Abbey M Jones, Emily E Petersen, Ellen H Lee, Marion E Rice, Andrea Bingham, Sascha R Ellington, Nicole Evert, Sarah Reagan-Steiner, Titilope Oduyebo, Catherine M Brown, Stacey Martin, Nina Ahmad, Julu Bhatnagar, Jennifer Macdonald, Carolyn Gould, Anne D Fine, Kara D Polen, Heather Lake-Burger, Christina L Hillard, Noemi Hall, Mahsa M Yazdy, Karnesha Slaughter, Jamie N Sommer, Alys Adamski, Meghan Raycraft, Shannon Fleck-Derderian, Jyoti Gupta, Kimberly Newsome, Madelyn Baez-Santiago, Sally Slavinski, Jennifer L White, Cynthia A Moore, Carrie K Shapiro-Mendoza, Lyle Petersen, Coleen Boyle, Denise J Jamieson, Dana Meaney-Delman, Margaret A Honein, U.S. Zika Pregnancy Registry Collaboration Vital Signs: Update on Zika Virus-Associated Birth Defects and Evaluation of All U.S. Infants with Congenital Zika Virus Exposure - U.S. Zika Pregnancy Registry, 2016. MMWR Morb. Mortal. Wkly. Rep.: 2017, 66(13);366-373 PubMed 28384133

Inner Ear Abnormalities

Large Vestibular Aqueduct Syndrome (LVAS)

Vestibular sac abnormality

This inner ear abnormality can be one of the common causes of hearing loss.

Common cavity, severe cochlear hypoplasia


Epithelium trapped within skull base in development, erosion of bones: temporal bone, middle ear, mastoid

Mondini Dysplasia

Incomplete cochlea CT[6]

(Mondini defect, Mondini malformation) Incomplete cochlea development, thought to occur during embryonic stage of growth. A common associated form of sensory neural hearing loss not associated with any known syndrome, as well as occurring as a feature of other congenital abnormalities (Turner's syndrome). Can be identified by CT scans of the head showing the cochlea region. First described by Carlo Mondini in 1791 "The Anatomic Section of a Boy Born Deaf".[7][8]

Increased risk of developing:

  • recurrent meningitis
  • perilymphatic fistula
  • a cerebrospinal fluid (CSF) leak due to either an enlarged cochlear aqueduct or an abnormal connection between the internal auditory canal and membranous labyrinth.

Autosomal Dominant Deafness

This form of deafness is caused by heterozygous mutation in the transmembrane cochlear-expressed gene-1 (TMC1) on chromosome 9 (9q21.13). The TMC1 protein is probably a membrane ion channel located at the tips of hair cells and required for the normal function of cochlear hair cells, it has been predicted to contain 6 transmembrane domains and to have cytoplasmic orientation of both N and C termini.

A recent study has used a mouse model of this mutation causing deafness and rescued hearing by use of gene therapy.[1] Such studies point to the future use of gene therapy for treatment of some genetic forms of deafness.

Links: OMIM TMC1

Middle Ear Abnormalities

Rare and can be part of first arch syndrome.

Fixation of the middle ear ossicles Malleus, Incus and Stapes Middle ear abnormalities (ossicular anomalies) are rare and can be part of first arch syndrome.

  • familial expansile osteolysis
  • malleus/incus fixation
  • absence of the long process of the incus
  • congenital fixation of stapes (stapes anchored to oval window)
  • failure of annular ligament development
  • cholesteatoma

Familial Expansile Osteolysis (FEO)

A rare congenital (autosomal dominant, 18q21.1-q22) disorder similar to Paget's disease of bone. Osteolytic lesions occur in all bones (mainly long bones) causing medullar expansions and lead eventually to middle ear and jaw abnormalities.[9]

Malleus/Incus Fixation

Congenital absence of the long process of the incus.[10]

Congenital Fixation of Stapes

In this condition the stapes is anchored to oval window often by growth of bone around the stapes (otosclerosis). Surgicallly treated by stapedectomy, where the bone and stapes is removed and replaced by a prosthesis.[11]


Squamous epithelium that has been trapped within the skull base during development (congenital) and also occurs in an acquired form. The presence of this abnormality leads to erosion of the bones (temporal bone, middle ear, or mastoid) in which the epithelium is embedded.

Persistent Stapedial Artery

Stapedial Artery

The fetal stapedial artery initially lies between the foramen of the stapes and is lost before birth. If this regression fails, a persistent stapedial artery will affect conduction through the middle ear ossicle chain.

The condition can be seen in hemifacial microsomia (14q32), a reasonably common sporadic and rare familial autosomal dominant abnormality of the first and second pharyngeal arch derivatives.[12][13]

Chronic Otitis Media

Associated with ossicular defects, the most frequent being necrosis of the long process of incus.

Outer Ear Abnormalities

Several genetic effects and syndromes can include impacts on developmental of the external ear either directly or by altering development of the skull or face. Several developmental environment effects can be indicated by changes in the relative position or appearance of the external ear at birth. (More? Abnormal Development - Fetal Alcohol Syndrome.

  • Microtia - abnormally small external ear
  • Preauricular sinus - occurs in 0.25% births, bilateral (hereditary) 25-50%, unilateral (mainly the left), duct runs inward can extend into the parotid gland, Postnatally sites for infection



The condition in humans of an abnormally small external ear is called "microtia".

This abnormality can generally be surgically repaired by use of rib cartilage to reconstruct the external ear.[14]

A recent study has identified a genetic mouse model for this condition with the knockout of the Pact gene.[15]

Preauricular Sinus

Preauricular sinus in ascending limb of the helix

Preauricular sinus occurs in 0.25% births, is bilateral (hereditary) in 25-50% of cases and unilateral (mainly the left). They are developmental and generally occur on the surface in anterior margin of the ascending limb of the helix, and the duct runs inward to the perichondrium of the auricular cartilage and in some cases extend into the parotid gland. Postnatally they are a site for infection, mainly Staphylococcus aureus and less commonly by Streptococcus and Proteus, leading to preauricular sinus abscess.

Search PubMed: Preauricular Sinus

Links: Medline Plus - Preauricular tag or pit

Preauricular Tag

Skin tags in front of the external ear opening are common in neonates and in most cases are normal, though in some cases are indicative of other associated abnormalities.

Preauricular tag Preauricular tag

Search PubMed: Preauricular Tag

Links: Medline Plus - Preauricular tag or pit

External Meatus Stenosis

Stenosis (narrowing) of the external auditory meatus is uncommon and can be due to chronic otitis externa or acquired atresia. The condition can be treated surgically by meatoplasty (reconstructive surgery of the canal) alone, though acquired atresia requires removal of the soft tissue plug and a split skin graft.

Search PubMed: external meatus stenosis

Congenital Deafness

Sensorineural - cochlear or central auditory pathway Conductive - disease of outer and middle ear


Cochlear or central auditory pathway

  • Hereditary
  • recessive- severe
  • dominant- mild
    • can be associated with abnormal pigmentation (hair and irises)
  • Acquired
    • rubella (German measles), maternal infection during 2nd month of pregnancy, vaccination of young girls
    • cytomegalovirus [16][17]
    • streptomycin
    • antibiotic
    • thalidomide
Links: Cytomegalovirus | Rubella | Drugs | Thalidomide


Disease of outer and middle ear

  • produced by otitis media with effusion, is widespread in young children.
  • temporary blockage of outer or middle ear

Ototoxic Medications

  • Aminoglycoside antibiotics – degeneration of inner hair cells.
  • Chemotherapeutic agents – cochlear metabolism toxicity
  • Salicylates – cochlear metabolism toxicity (reversible).
  • Nonsteroidal anti-inflammatory drugs – cochlear metabolism toxicity (reversible).
  • Quinine – cochlear metabolism toxicity.
  • Loop diuretics - degeneration of inner hair cells.
  • Erythromycin – possible effect on central nervous system pathways.
  • Vancomycin – etiology unknown, usually enhances aminoglycocide toxicity.


Newborn Hearing Screening


Newborn hearing test

In Australia, there is now an early postnatal screening of neonatal hearing as part of a NSW State Wide Infant Screening Hearing (SWISH) Program using Automated Auditory Brainstem Response (AABR).

Links: NSW Statewide Infant Screening - Hearing (SWISH) Program


Multicenter newborn hearing screening project[3] "From the actual point of view, the "sensitive period" for the effects of hearing impairment on speech and language development is within the first year of life. Early exposure to acoustic or electric stimulation can compensate for the acoustic deficit. A regional-based, specifically designed concept of a universal newborn hearing screening (UNHS) was started in Hamburg in the year 2002. ...Sixty-three thousand, four hundred fifty-nine out of 65,466 births were registered during the period August 2002 to July 2006, 93% were primarily screened. 3.3% failed the test and 31.3% were lost to follow-up. A total of 118 children were diagnosed with hearing loss in the follow-up."


Very low birthweight infants and universal newborn hearing screening[19] "very low birth weight (VLBW) infants in resource-poor settings are associated with the risk of sensorineural hearing loss and other perinatal outcomes that may potentially compromise their optimal development in early childhood."

Cochlear Implant

Cochlear implant (NIDCD - Cochlear Implants)

The "Bionic Ear" was pioneered in development by Professor Graeme Clark in Australia (1960s) and first successfully used in 1978, there are now a variety of different implant devices.[20] By the year 2000 more than 13,000 children worldwide have received these implants. The medical device consists of an array of electrodes implanted within cochlea, that directly electrically stimulate the auditory nerve fibres.

The sound used to test persons with cochlear implants can be delivered by two methods, referred to as ‘‘HL’’ (hearing level) and ‘‘SPL’’ (sound pressure level), both of these methods are expressed in dB, but a specific dB HL is not the same level of loudness as the same dB SPL.

  • Young children with cochlear implants compared with children with normal hearing.[21]

Fetal Alcohol Syndrome

Fetal Alcohol Syndrome Face
  • Postion- Lower or uneven height, "railroad track” appearance, curve at top part of outer ear is under-developed, folded over parallel to curve beneath
Links: Abnormal Development - Fetal Alcohol Syndrome


  1. 1.0 1.1 Charles Askew, Cylia Rochat, Bifeng Pan, Yukako Asai, Hena Ahmed, Erin Child, Bernard L Schneider, Patrick Aebischer, Jeffrey R Holt Tmc gene therapy restores auditory function in deaf mice. Sci Transl Med: 2015, 7(295);295ra108 PubMed 26157030
  2. Liliana Gabrielli, Maria Paola Bonasoni, Donatella Santini, Giulia Piccirilli, Angela Chiereghin, Brunella Guerra, Maria Paola Landini, Maria Grazia Capretti, Marcello Lanari, Tiziana Lazzarotto Human fetal inner ear involvement in congenital cytomegalovirus infection. Acta Neuropathol Commun: 2013, 1(1);63 PubMed 24252374
  3. 3.0 3.1 Anna-Katharina Rohlfs, Thomas Wiesner, Holger Drews, Frank Müller, Achim Breitfuss, Regina Schiller, Markus Hess Interdisciplinary approach to design, performance, and quality management in a multicenter newborn hearing screening project: introduction, methods, and results of the newborn hearing screening in Hamburg (Part I). Eur. J. Pediatr.: 2010, 169(11);1353-60 PubMed 20549232
  4. Isabelle Schrauwen, Guy Van Camp The etiology of otosclerosis: a combination of genes and environment. Laryngoscope: 2010, 120(6);1195-202 PubMed 20513039
  5. A L Poirrier, P Van den Ackerveken, T S Kim, R Vandenbosch, L Nguyen, P P Lefebvre, B Malgrange Ototoxic drugs: difference in sensitivity between mice and guinea pigs. Toxicol. Lett.: 2010, 193(1);41-9 PubMed 20015469
  6. S M Shah, S S Prabhu, R H Merchant Mondini defect. J Postgrad Med: 2002, 47(4);272-3 PubMed 11832648
  7. Mondini C. Anatomia surdi nati sectio: De Bononiensi Scientiarum et Artium Institute atque Academia commentarii. Bononiae. 1791;7:419-428
  8. W W Lo What is a 'Mondini' and what difference does a name make? AJNR Am J Neuroradiol: 1999, 20(8);1442-4 PubMed 10512226
  9. Ahmad Daneshi, Yousef Shafeghati, Mohammad Hassan Karimi-Nejad, Amir Khosravi, Fariba Farhang Hereditary bilateral conductive hearing loss caused by total loss of ossicles: a report of familial expansile osteolysis. Otol. Neurotol.: 2005, 26(2);237-40 PubMed 15793411
  10. R E Wehrs Congenital absence of the long process of the incus. Laryngoscope: 1999, 109(2 Pt 1);192-7 PubMed 10890764
  11. Michael D Seidman, Seilesh Babu A new approach for malleus/incus fixation: no prosthesis necessary. Otol. Neurotol.: 2004, 25(5);669-73 PubMed 15353993
  12. G J Carvalho, C S Song, K Vargervik, A K Lalwani Auditory and facial nerve dysfunction in patients with hemifacial microsomia. Arch. Otolaryngol. Head Neck Surg.: 1999, 125(2);209-12 PubMed 10037288
  13. R Silbergleit, D J Quint, B A Mehta, S C Patel, J J Metes, S E Noujaim The persistent stapedial artery. AJNR Am J Neuroradiol: 2000, 21(3);572-7 PubMed 10730654
  14. Shane Aldwin Zim Microtia reconstruction: an update. Curr Opin Otolaryngol Head Neck Surg: 2003, 11(4);275-81 PubMed 14515077
  15. M Granitzer, W Nagel, J Crabbé Voltage dependent membrane conductances in cultured renal distal cells. Biochim. Biophys. Acta: 1991, 1069(1);87-93 PubMed 1657165
  16. Yoav Yinon, Dan Farine, Mark H Yudin, Robert Gagnon, Lynda Hudon, Melanie Basso, Hayley Bos, Marie-Franc Delisle, Savas Menticoglou, William Mundle, Annie Ouellet, Tracy Pressey, Anne Roggensack, Marc Boucher, Eliana Castillo, Andrée Gruslin, Deborah M Money, Kellie Murphy, Gina Ogilvie, Caroline Paquet, Nancy Van Eyk, Julie van Schalkwyk, Fetal Medicine Committee, Society of Obstetricians and Gynaecologists of Canada Cytomegalovirus infection in pregnancy. J Obstet Gynaecol Can: 2010, 32(4);348-54 PubMed 20500943
  17. Natacha Teissier, Anne-Lise Delezoide, Anne-Elisabeth Mas, Suonavy Khung-Savatovsky, Bettina Bessières, Jeannette Nardelli, Christelle Vauloup-Fellous, Olivier Picone, Nadira Houhou, Jean-François Oury, Thierry Van Den Abbeele, Pierre Gressens, Homa Adle-Biassette Inner ear lesions in congenital cytomegalovirus infection of human fetuses. Acta Neuropathol.: 2011, 122(6);763-74 PubMed 22033878
  18. NSW Statewide Infant Screening - Hearing (SWISH) Program Guideline (2010) PDF
  19. Bolajoko O Olusanya Perinatal profile of very low birthweight infants under a universal newborn hearing screening programme in a developing country: a case-control study. Dev Neurorehabil: 2010, 13(3);156-63 PubMed 20450464
  20. Graeme M Clark Personal reflections on the multichannel cochlear implant and a view of the future. J Rehabil Res Dev: 2008, 45(5);651-93 PubMed 18816421 JRRD
  21. Bianka Schramm, Andrea Bohnert, Annerose Keilmann Auditory, speech and language development in young children with cochlear implants compared with children with normal hearing. Int. J. Pediatr. Otorhinolaryngol.: 2010, 74(7);812-9 PubMed 20452685

Online Textbooks



Kirsten Dutton, Leila Abbas, Joanne Spencer, Claire Brannon, Catriona Mowbray, Masataka Nikaido, Robert N Kelsh, Tanya T Whitfield A zebrafish model for Waardenburg syndrome type IV reveals diverse roles for Sox10 in the otic vesicle. Dis Model Mech: 2008, 2(1-2);68-83 PubMed 19132125

Douglas H Keefe, Michael P Gorga, Walt Jesteadt, Lynette M Smith Ear asymmetries in middle-ear, cochlear, and brainstem responses in human infants. J. Acoust. Soc. Am.: 2008, 123(3);1504-12 PubMed 18345839

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Search Pubmed: Abnormalities | Microtia | Middle ear ossicular anomalies | familial expansile osteolysis | cholesteatoma | | cochlear implant |

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Cite this page: Hill, M.A. 2017 Embryology Sensory - Hearing Abnormalities. Retrieved April 26, 2017, from

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