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Lop ear

MedGen UID:
Concept ID:
Congenital Abnormality
Synonym: Lop ears
SNOMED CT: Bat ear (76223006)
HPO: HP:0000394


Anterior and inferior folding of the upper portion of the ear that obliterates triangular fossa and scapha. [from HPO]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVLop ear

Conditions with this feature

CHARGE association
MedGen UID:
Concept ID:
Disease or Syndrome
CHD7 disorder encompasses the entire phenotypic spectrum of heterozygous CHD7 pathogenic variants that includes CHARGE syndrome as well as subsets of features that comprise the CHARGE syndrome phenotype. The mnemonic CHARGE syndrome, introduced in the premolecular era, stands for coloboma, heart defect, choanal atresia, retarded growth and development, genital hypoplasia, ear anomalies (including deafness). Following the identification of the genetic cause of CHD7 disorder, the phenotypic spectrum expanded to include cranial nerve anomalies, vestibular defects, cleft lip and/or palate, hypothyroidism, tracheoesophageal anomalies, brain anomalies, seizures, and renal anomalies. Life expectancy highly depends on the severity of manifestations; mortality can be high in the first few years when severe birth defects (particularly complex heart defects) are present and often complicated by airway and feeding issues. In childhood, adolescence, and adulthood, decreased life expectancy is likely related to a combination of residual heart defects, infections, aspiration or choking, respiratory issues including obstructive and central apnea, and possibly seizures. Despite these complications, the life expectancy for many individuals can be normal.
Ehlers-Danlos syndrome, classic type, 1
MedGen UID:
Concept ID:
Disease or Syndrome
Classic Ehlers-Danlos syndrome (cEDS) is a connective tissue disorder characterized by skin hyperextensibility, atrophic scarring, and generalized joint hypermobility (GJH). The skin is soft and doughy to the touch, and hyperextensible, extending easily and snapping back after release (unlike lax, redundant skin, as in cutis laxa). The skin is fragile, as manifested by splitting of the dermis following relatively minor trauma, especially over pressure points (knees, elbows) and areas prone to trauma (shins, forehead, chin). Wound healing is poor, and stretching of scars after apparently successful primary wound healing is characteristic. Complications of joint hypermobility, such as dislocations of the shoulder, patella, digits, hip, radius, and clavicle, usually resolve spontaneously or are easily managed by the affected individual. Other features include hypotonia with delayed motor development, fatigue and muscle cramps, and easy bruising. Mitral valve prolapse can occur infrequently, but tends to be of little clinical consequence. Aortic root dilatation has been reported, appears to be more common in young individuals, and rarely progresses.
Corpus callosum agenesis-intellectual disability-coloboma-micrognathia syndrome
MedGen UID:
Concept ID:
Disease or Syndrome
Corpus callosum agenesis-intellectual disability-coloboma-micrognathia syndrome is a developmental anomalies syndrome characterized by coloboma of the iris and optic nerve, facial dysmorphism (high forehead, microretrognathia, low-set ears), intellectual deficit, agenesis of the corpus callosum (ACC), sensorineural hearing loss, skeletal anomalies and short stature.
Temtamy syndrome
MedGen UID:
Concept ID:
Disease or Syndrome
Temtamy syndrome is a mental retardation/multiple congenital anomaly syndrome characterized by variable craniofacial dysmorphism, ocular coloboma, seizures, and brain abnormalities, including abnormalities of the corpus callosum and thalamus (summary by Akizu et al., 2013).
Syndactyly-telecanthus-anogenital and renal malformations syndrome
MedGen UID:
Concept ID:
Disease or Syndrome
Syndrome with the association of toe syndactyly, facial dysmorphism including telecanthus and a broad nasal tip, urogenital malformations and anal atresia. Around ten cases have been reported so far. The syndrome is caused by mutations in the FAM58A gene (located on the X chromosome) encoding a protein of unknown function.
Townes-Brocks syndrome 1
MedGen UID:
Concept ID:
Disease or Syndrome
Townes-Brocks syndrome (TBS) is characterized by the triad of imperforate anus (84%), dysplastic ears (87%; overfolded superior helices and preauricular tags; frequently associated with sensorineural and/or conductive hearing impairment [65%]), and thumb malformations (89%; triphalangeal thumbs, duplication of the thumb [preaxial polydactyly], and rarely hypoplasia of the thumbs). Renal impairment (42%), including end-stage renal disease (ESRD), may occur with or without structural abnormalities (mild malrotation, ectopia, horseshoe kidney, renal hypoplasia, polycystic kidneys, vesicoutereral reflux). Congenital heart disease occurs in 25%. Foot malformations (52%; flat feet, overlapping toes) and genitourinary malformations (36%) are common. Intellectual disability occurs in approximately 10% of individuals. Rare features include iris coloboma, Duane anomaly, Arnold-Chiari malformation type 1, and growth retardation.

Professional guidelines


Charipova K, Rogers A, Barra C, Baker SB
Plast Reconstr Surg 2022 Nov 1;150(5):1049e-1056e. Epub 2022 Aug 24 doi: 10.1097/PRS.0000000000009638. PMID: 35998128

Recent clinical studies


Kim YS, Chung S
J Plast Reconstr Aesthet Surg 2016 Apr;69(4):e71-6. Epub 2016 Feb 2 doi: 10.1016/j.bjps.2016.01.009. PMID: 26922051
Yotsuyanagi T, Yamauchi M, Yamashita K, Sugai A, Gonda A, Kitada A, Saito T, Urushidate S
Plast Reconstr Surg 2015 Jul;136(1):78e-88e. doi: 10.1097/PRS.0000000000001383. PMID: 26111335
Byrd HS, Langevin CJ, Ghidoni LA
Plast Reconstr Surg 2010 Oct;126(4):1191-1200. doi: 10.1097/PRS.0b013e3181e617bb. PMID: 20453717
Horlock N, Grobbelaar AO, Gault DT
Plast Reconstr Surg 1998 Dec;102(7):2325-32; discussion 2333-5. doi: 10.1097/00006534-199812000-00008. PMID: 9858166
Tanzer RC
Plast Reconstr Surg 1975 Apr;55(4):406-15. PMID: 1118500


Li J, Tan J, Yang D, Chen L
BMC Pediatr 2023 Mar 3;23(1):101. doi: 10.1186/s12887-023-03916-3. PMID: 36869317Free PMC Article
Zhao H, Lin G, Seong YH, Shi J, Xu J, Huang W
J Matern Fetal Neonatal Med 2019 Apr;32(7):1176-1183. Epub 2017 Dec 8 doi: 10.1080/14767058.2017.1402877. PMID: 29219007
Garg A, Wadhera R, Gulati SP, Kumar A
J Assoc Physicians India 2008 Nov;56:904-5. PMID: 19263692


Ho K, Boorer C, Khan U, Deva A, Chang L
J Plast Reconstr Aesthet Surg 2006;59(5):494-8. doi: 10.1016/j.bjps.2005.09.029. PMID: 16749194
Horlock N, Grobbelaar AO, Gault DT
Plast Reconstr Surg 1998 Dec;102(7):2325-32; discussion 2333-5. doi: 10.1097/00006534-199812000-00008. PMID: 9858166
Park C
Plast Reconstr Surg 1997 Jun;99(7):1846-57. doi: 10.1097/00006534-199706000-00007. PMID: 9180708

Clinical prediction guides

Li J, Tan J, Yang D, Chen L
BMC Pediatr 2023 Mar 3;23(1):101. doi: 10.1186/s12887-023-03916-3. PMID: 36869317Free PMC Article
Leonardi A, Bianca C, Basile E, Ungari C, Arangio P, Filiaci F, Papoff P, Vellone V, Moretti C, Cascone P
Eur Rev Med Pharmacol Sci 2012 Oct;16(11):1554-8. PMID: 23111969
Singh P, Purkait R
Homo 2009;60(5):461-72. Epub 2009 Sep 11 doi: 10.1016/j.jchb.2009.08.002. PMID: 19748090
Matsuo K, Hayashi R, Kiyono M, Hirose T, Netsu Y
Clin Plast Surg 1990 Apr;17(2):383-95. PMID: 2189652

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