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Rare Defect at Superior Helix As Morphological Variation of Right Auricle

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Rare Defect at Superior Helix As Morphological Variation of Right Auricle International Journal of Research in Medical Sciences Parwanto MLE. Int J Res Med Sci. 2018 May;6(5):1800-1803 www.msjonline.org pISSN 2320-6071 | eISSN 2320-6012 DOI: http://dx.doi.org/10.18203/2320-6012.ijrms20181780 Case Report Rare defect at superior helix as morphological variation of right auricle Mauritius Lambertus Edy Parwanto* Department of Biology, Faculty of Medicine, University of Trisakti, Indonesia Received: 25 March 2018 Revised: 16 April 2018 Accepted: 20 April 2018 *Correspondence: Dr. Mauritius Lambertus Edy Parwanto, E-mail: [email protected] Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT Auricle is the part of external ear. Morphological appearance and biometric of auricle are influenced by genetic and environmental factors. Base on the fact that morphological appearance and biometric of auricle vary in different human ethnic races. Normal of auricle have complete component with normal of dimension and appearance. Population studies show the different of morphological and biometric of auricle. Generally, the right and left auricles in the individual is symmetrical in both size and appearance. We reported about defect at superior helix of right auricle. In this case it shows that right and left auricles have complete components. The biometric comparison of right and left auricles showed equal or not significant different. Defect of right auricle at superior helix were indentation as morphological variation. Keywords: Auricle, Morphological defect, Superior helix INTRODUCTION years in female, but for males it stopped around age of 50-70 years.5 The human ear is divided into 3 parts, namely outer, middle and inner parts. The human auricle is part of the Base on the fact that there was a variety of morphological outer ear. Morphologically, the outer ear consists of three and biometric appearance of human auricle. There are main components that are the helical complexes, the shell individuals who have a right and left auricles with complex, and the lobe.1 Generally, the human auricle morphological and biometric in the normal size, but there consists of helix, anti-helix, tragus, anti-tragus, concha, are also individuals who have one or both auricles with lobe, scapha and triangular fossa. morphological and biometric in the abnormal size. Auricle is one of five main characteristics of the human The morphological appearance and biometric of auricle face and is very influential in determining its 6 vary in different human ethnic races.2 Moreover, the appearance. Type of external ear malformations that characteristic of morphological appearance and biometric affect to the facial appearance can be found, among of auricle in individual are influenced by genetic and others in oculo-auriculo-vertebral spectrum patients ran- environment factors.3,4 Because that, of course that the ged from slightly dysmorphic to absent ears (or anotia: 7 shape, size and orientation of each auricle in individual is the most severe form of microtia). specific and associate with genetic and or environment factors. With regard to auricle size, length and width of The incidence of outer ear malformation has been the auricle increase with age. The increase in length and reported at 1: 6830.8 Previous studies have shown that width of the auricle occurs from birth to the age of 99 auricle morphological defects are caused by congenital International Journal of Research in Medical Sciences | May 2018 | Vol 6 | Issue 5 Page 1800 Parwanto MLE. Int J Res Med Sci. 2018 May;6(5):1800-1803 malformations and or external factors such as trauma, (Figure 1A), whereas the right auricle has an abnormal burns, tumors, punctured defects, scars, and morphological appearance (Figure 1B). Defect of right inflammation/allergies.4 More over that congenital defect auricle shows the presence indentation at the superior of auricle show varying degrees, and is more commonly helix along 2.1cm (see red mark at Figure 1B). Based on unilateral than bilateral, more effecting on the right ear morphological examination in this case, we believe that than left ear and occurs in males more than females.9 superior helix indentation is due to abnormalities of Certainly, the consequences of congenital defect will cartilage tissue synthesis. affect the morphological variation in the individual. In this case, we reported about defect at superior helix of right auricle on Indonesian men. CASE REPORT Table 1: Anatomical landmarks of ear biometrics. Anatomical landmarks of ear Left Right biometrics auricle auricle 1. Total Ear Length (TEL): the distance between superior most 73.23 73.01 pinna point to inferior most point of lobule (mm). 2. Ear length above tragus (ELAT): A B distance between superior point of 33.14 32.69 ear to tragion (mm). 3. Ear length below tragus (ELBT): distance between intertragic incisure 22.76 23.12 to lower most lobule point (mm). 4. Tragus length (TL): distance between tragion to intertragic 24.14 24.16 incisures (mm). 5. Ear breadth (EB): distance between maximum convexity of the 27.21 27.26 helix and the root of ear (mm). 6. Concha length (CL): distance between intertragic incisures and 38.17 38.24 C D cymba concha (mm). 7. Concha breadth (CB): distance between maximum concavity of the Figure 1: Morphological appearance and biometric 22.11 21.85 anti-helix and posterior margin of measurement of auricles. A) Left auricle showed tragus (mm). complete of all components and normal appearance. 8. Lobule height (LH): distance B) Right auricle showed complete of all components between inferior most point of with defect at superior helix. C) Biometric 08.26 08.28 external ear attachment head up to measurement of left auricle showed normal the free margins of ear lobe (mm). appearance. D) Biometric measurement of right 9. Lobule width (LW): distance auricle with defect (shows indentation along 2.1 between outermost maximum centimeter) at superior helix (see Red mark). transverse width of ear lobule and 23.42 23.37 caudal most attachment of ear Biometric of the right and left auricles are measured lobule (mm) (Figure 1C, Figure 1D). The parameters were total ear 10. Ear index (EI): (ear breadth: length (TEL), ear length above tragus (ELAT), ear length 37.15 37.33 total ear lenght) x 100 below tragus (ELBT), tragus length (TL), ear breadth 11. Lobule index (LI): (lobule (EB), concha length (CL), concha breadth (CB), lobule 283.53 282.24 width: lobule height) x 100 height (LH), lobule width (LW), ear index (EI) and Abbreviations: mm= millimetres lobule index (LI) for right and left auricles of the subject. All the measurements were done on bilateral of auricles A 61 years old Indonesian men has body height of 180 using standard digital Vernier’s caliper with measuring centimeter (cm) and body weight 83 kilogram (kg), has a capability to the nearest 0.1 millimeter (mm). Biometrics complete component on the right and left auricles. The of right and left auricles showed in Table 1. left auricle has a normal morphological appearance International Journal of Research in Medical Sciences | May 2018 | Vol 6 | Issue 5 Page 1801 Parwanto MLE. Int J Res Med Sci. 2018 May;6(5):1800-1803 Based on the results of biometric measurement in this reported that the missense mutation of Hoxa-2 gene in a case, it shows that ELBT, TL, EB, CL, LH, and EI of consanguineous Iranian family segregating for an right auricle are longer than left auricle, and the other autosomal recessive form of bilateral microtia.16 hand TEL, ELAT, CB, LW and LI of left auricle are Certainly, Hoxa-2 gene organises patterns of cell longer than right auricle. proliferation and which will contribute to the control of auricle appearance. Severerity of Hoxa-2 gene mutation DISCUSSION corresponds to severerity of auricle morphological defect. Morphologically, the auricle appearance is normal and The size of normal auricle depends on various factors some are abnormal, both of which give meaning to such as age,4 gender, and body height has been morphological variations. It has been reported that reported.2,4 The TEL in adults is about 58-66mm (in abnormal auricle displays are caused by genetic factors. women 58–63 mm and men 62-66mm) and EB Genetic defect can caused embryonic development defect approximately 32-34mm.4 Based on guideline used by (congenital abnormalities). In the other hand, auricle Storck et al, TEL of the left and right auricles in this case deformities may be caused by tumor resection, trauma, is longer and EB is normal.4 Beside that the TEL and LW burns, and infections.10 We know that external ear in this case are longer than means of population study development is a lengthy and complex process that results.2,5 The ELAT, ELBT, TL, CL, CB in this case are extends from early embryonic life until well into the also longer than the results of population studies in postnatal period. The development of auricle and external Northwest India and Northeast India, but EB and LH are auditory canal during the fourth and fifth weeks of the opposite. The EI in this case is smaller than the results gestation. Additionally that auricle development of population studies in Northwest India and Northeast associated with many congenital disorders and India. LI of the right auricle in this case is longer than the syndromes.11 Morphological defect of right auricle at average of population study result in Northwest India and superior helix in this case accordance to the statement is smaller than the results of population studies in that external ear malformation generally on right ear and Northeast India.
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