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Sulcus vocalis in monozygotic twins
Auris Nasus Larynx 37 (2010) 255–257 www.elsevier.com/locate/anl
Sulcus vocalis in monozygotic twins Zeynep Alkan Cakir a,*, Ozgur Yigit a, Ismail Kocak b, A. Volkan Sunter a, Muzeyyen Dogan b a
Istanbul Education and Research Hospital, Otolaryngology Department, Istanbul, Turkey b Yeditepe University, Otolaryngology Department, Istanbul, Turkey Received 23 January 2009; accepted 14 March 2009 Available online 7 May 2009
Abstract Sulcus vocalis is the presence of a groove extending along the vibratory surface of a vocal fold and may result in dysphonia. Depending on the level of severity, this condition may require treatment involving complicated surgical techniques. Cases of sulcus vocalis are classified as physiological, vergeture, or pouch type. A clear explanation of the etiology has not been established, and the currently proposed congenital origin, as described in the literature, remains controversial. This paper presents findings from monozygotic twin sisters with bilateral sulcus vocalis; these patients had similar morphologies, vibratory characteristics, and vocal quality measurements, which support the theory of a congenital etiology. # 2009 Elsevier Ireland Ltd. All rights reserved. Keywords: Congenital etiology; Monozygotic twins; Sulcus vocalis
1. Introduction Sulcus vocalis refers to an anomalous groove extending along the free edge of a vocal fold. These defects may occur bilaterally or unilaterally, and may inhibit closure of the vocal folds or cause stiffness in the vocal fold mucosa, resulting in dysphonia. Ford et al. [1] classified sulcus vocalis cases into three groups. Type 1 refers to cases in which the sulcus is composed of an epithelial invagination into the lamina propria that does not cause a vibratory disturbance. Type 2 indicates sulcus vergeture, which is characterized by epithelial invagination down the vocal ligament that results in vibratory disturbances. Type 3 refers to true sulcus vocalis and indicates an epithelial invagination that completely penetrates the vocal ligament and causes severe dysphonia. In the literature, the frequency of adult sulcus vocalis ranges widely from 0.4 to 48% [2]. One study also reported that sulcus vocalis causes 5% of the cases of dysphonia in * Corresponding author at: Siracevizler Cad Isik Ap No: 108/5, D: 3 34381 Sisli/Istanbul, Turkey. Tel.: +90 532 326 32 08/212 632 00 63; fax: +90 212 632 00 60. E-mail address: [email protected] (Z.A. Cakir).
children [3]. The differences in the reported frequencies of sulcus vocalis may be due to variation in diagnostic approaches and difficulty in diagnosing type 1 sulci. Although a consensus has not been reached, theories involving congenital and acquired origins have been proposed. Demographically, sulcus vocalis has not been associated with a specific region or race. The present paper discusses two monozygotic twin sisters who were found to have bilateral sulcus vocalis; the characteristics of these two patients appear to support a congenital origin for sulcus vocalis development.
2. Case report Fourteen-year-old monozygotic twin sisters were admitted to our hospital with a history of dysphonia since birth. The parents claimed that the twins sometimes experienced total aphonia, which caused difficulty at school and social withdrawal. The twins did not have a history of vocal trauma or childhood infections that could have affected the vocal folds, nor did they demonstrate any change in voice quality over time.
0385-8146/$ – see front matter # 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.anl.2009.03.007
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Z.A. Cakir et al. / Auris Nasus Larynx 37 (2010) 255–257
Fig. 1. (A and B) Videolaryngostroboscopic examination of twins.
Laryngostroboscopic examinations revealed sulcus vocalis type 1 on the left and sulcus vocalis type 2 on the contralateral folds in both twins. Under stroboscopic examination, a consistent, spindle-shaped, incomplete vibratory closure was observed between the vocal cords. In both patients, mucosal waves broke when they reached the edges of the sulci and the amplitudes of mucosal waves were diminished. The appearances and types of the sulci were almost symmetrical (Fig. 1). The twins presented with breathy voices and severe hoarseness. Acoustically, the voices of both patients were strained and diplophonic. The fundamental frequencies were measured as 258.804 and 264.867 Hz, and the maximum phonation times were 2.62 and 2.45 s with s/z ratios of 2.234 and 1.66, respectively. Our management plan based on is the follow-up until patients reach 18 years old.
3. Discussion The reported frequency of sulcus disorders varies. In postmortem studies, Shin [2] found a frequency of 0.4% in 1200 cases. Ishii et al. [2] reported a frequency of 2.5% in their study involving 200 autopsies. Nakayama et al. [4] reported the presence of sulci in 20% of normal cases and 48% of cases with laryngeal cancer. Additionally, Hsiung et al. [5] reported a frequency of 23%, which was consistent with that reported by Nakayama et al. [4], and attributed the wide range of previously reported frequencies to artifacts during pathologic investigations, differences in the processing of specimens, and the misdiagnosis of type 1 sulci upon gross physical examination. The etiology of sulcus vocalis is still under debate. In the beginning of the 20th century, some investigators supported the congenital theory and attributed sulcus development to Darwin’s theory of evolution. This version of the congenital theory proposed that the accessory vocal fold reappears during the developmental period [2]. However, Bouchayer et al. [6] claimed that sulcus vocalis is a congenital disease
arising from developmental defects of the fourth and sixth branchial arches. Type 2 and type 3 sulci may be caused by ruptured epidermoid cysts. Bouchayer et al. [6] classified sulci as epidermoid cysts or mucosal bridges. As further evidence of this theory, the authors noted that the frequency of dysphonia existing from childhood was 55%. The alternative concept, that sulcus vocalis is an acquired condition, was proposed by Itoh [2]. In support of this study, described a cohort in which two-thirds of the patients had developed dysphonia after their 40s and argued that the rupture of bilateral cysts was an improbable etiology of bilateral sulcus vocalis. According to a report from the University of Wisconsin, sulcus vocalis was found in 48% of cases as a coincidental finding of histological examination after the resection of laryngeal cancer [4]. Upon pathological examination, increased fibrous tissue and vascularity were observed, which suggested that inflammation and irritation play a major role in pathogenesis. A number of previous studies have stated that chronic irritation, inflammation, and age play important roles in the emergence of sulcus vocalis [1,2,4,7]. In regard to the twins described here, dysphonia had been present since birth, supporting the congenital theory. The symmetric localization and similarities in the sulci in both patients further supports the congenital theory of sulcus development. A recent case report described the presence of sulcus vocalis in four members of a family, reinforcing the hypothesis of a genetic origin even in the absence of identified phenotypic or karyotypic alterations [8]. Consequently, the karyotype of our monozygotic twin patients may be important for investigating the genetic etiology of sulcus vocalis.
References [1] Ford CN, Inagi K, Khidr A, Bless DM, Gilchrist KW. Sulcus vocalis: a rational approach to diagnosis and management. Ann Otol Rhinol Laryngol 1996;105:189–200. [2] Giovanni A, Chanteret C, Lagier A. Sulcus vocalis: a review. Eur Arch Otorhinolaryngol 2007;264:337–44.
Z.A. Cakir et al. / Auris Nasus Larynx 37 (2010) 255–257 [3] Xu Z, Xia Z, Wang Z, Jiang F. Pediatric sulcus vocalis. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2007;21(12):550–1. [4] Nakayama M, Ford CN, Brandenburg JH, Bless DM. Sulcus vocalis in laryngeal cancer: a histopathologic study. Laryngoscope 1994;104: 16–24. [5] Hsiung MW, Woo P, Wang HW, Su WY. A clinical classification and histopathological study of sulcus vocalis. Eur Arch Otorhinolaryngol 2000;257:466–8.
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[6] Bouchayer M, Cornut G, Witzig E, Loire R, Roch JB, Bastian RW. Epidermoid cyst, sulci, and mucosal bridges of the true vocal cord: a report of 157 cases. Laryngoscope 1985;95:1087–94. [7] Hirano M, Yoshida T, Tanaka S, Hibi S. Sulcus vocalis: functional aspects. Ann Otol Rhinol Laryngol 1990;99:679–88. [8] Martins RH, Silva R, Ferreira DM, Dias NH. Sulcus vocalis: probable genetic etiology. Report of four cases in close relatives. Rev Bras Otorhinolaryngol 2007;73(4):573.
Sulcus vocalis in monozygotic twins Zeynep Alkan Cakir a,*, Ozgur Yigit a, Ismail Kocak b, A. Volkan Sunter a, Muzeyyen Dogan b a
Istanbul Education and Research Hospital, Otolaryngology Department, Istanbul, Turkey b Yeditepe University, Otolaryngology Department, Istanbul, Turkey Received 23 January 2009; accepted 14 March 2009 Available online 7 May 2009
Abstract Sulcus vocalis is the presence of a groove extending along the vibratory surface of a vocal fold and may result in dysphonia. Depending on the level of severity, this condition may require treatment involving complicated surgical techniques. Cases of sulcus vocalis are classified as physiological, vergeture, or pouch type. A clear explanation of the etiology has not been established, and the currently proposed congenital origin, as described in the literature, remains controversial. This paper presents findings from monozygotic twin sisters with bilateral sulcus vocalis; these patients had similar morphologies, vibratory characteristics, and vocal quality measurements, which support the theory of a congenital etiology. # 2009 Elsevier Ireland Ltd. All rights reserved. Keywords: Congenital etiology; Monozygotic twins; Sulcus vocalis
1. Introduction Sulcus vocalis refers to an anomalous groove extending along the free edge of a vocal fold. These defects may occur bilaterally or unilaterally, and may inhibit closure of the vocal folds or cause stiffness in the vocal fold mucosa, resulting in dysphonia. Ford et al. [1] classified sulcus vocalis cases into three groups. Type 1 refers to cases in which the sulcus is composed of an epithelial invagination into the lamina propria that does not cause a vibratory disturbance. Type 2 indicates sulcus vergeture, which is characterized by epithelial invagination down the vocal ligament that results in vibratory disturbances. Type 3 refers to true sulcus vocalis and indicates an epithelial invagination that completely penetrates the vocal ligament and causes severe dysphonia. In the literature, the frequency of adult sulcus vocalis ranges widely from 0.4 to 48% [2]. One study also reported that sulcus vocalis causes 5% of the cases of dysphonia in * Corresponding author at: Siracevizler Cad Isik Ap No: 108/5, D: 3 34381 Sisli/Istanbul, Turkey. Tel.: +90 532 326 32 08/212 632 00 63; fax: +90 212 632 00 60. E-mail address: [email protected] (Z.A. Cakir).
children [3]. The differences in the reported frequencies of sulcus vocalis may be due to variation in diagnostic approaches and difficulty in diagnosing type 1 sulci. Although a consensus has not been reached, theories involving congenital and acquired origins have been proposed. Demographically, sulcus vocalis has not been associated with a specific region or race. The present paper discusses two monozygotic twin sisters who were found to have bilateral sulcus vocalis; the characteristics of these two patients appear to support a congenital origin for sulcus vocalis development.
2. Case report Fourteen-year-old monozygotic twin sisters were admitted to our hospital with a history of dysphonia since birth. The parents claimed that the twins sometimes experienced total aphonia, which caused difficulty at school and social withdrawal. The twins did not have a history of vocal trauma or childhood infections that could have affected the vocal folds, nor did they demonstrate any change in voice quality over time.
0385-8146/$ – see front matter # 2009 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.anl.2009.03.007
256
Z.A. Cakir et al. / Auris Nasus Larynx 37 (2010) 255–257
Fig. 1. (A and B) Videolaryngostroboscopic examination of twins.
Laryngostroboscopic examinations revealed sulcus vocalis type 1 on the left and sulcus vocalis type 2 on the contralateral folds in both twins. Under stroboscopic examination, a consistent, spindle-shaped, incomplete vibratory closure was observed between the vocal cords. In both patients, mucosal waves broke when they reached the edges of the sulci and the amplitudes of mucosal waves were diminished. The appearances and types of the sulci were almost symmetrical (Fig. 1). The twins presented with breathy voices and severe hoarseness. Acoustically, the voices of both patients were strained and diplophonic. The fundamental frequencies were measured as 258.804 and 264.867 Hz, and the maximum phonation times were 2.62 and 2.45 s with s/z ratios of 2.234 and 1.66, respectively. Our management plan based on is the follow-up until patients reach 18 years old.
3. Discussion The reported frequency of sulcus disorders varies. In postmortem studies, Shin [2] found a frequency of 0.4% in 1200 cases. Ishii et al. [2] reported a frequency of 2.5% in their study involving 200 autopsies. Nakayama et al. [4] reported the presence of sulci in 20% of normal cases and 48% of cases with laryngeal cancer. Additionally, Hsiung et al. [5] reported a frequency of 23%, which was consistent with that reported by Nakayama et al. [4], and attributed the wide range of previously reported frequencies to artifacts during pathologic investigations, differences in the processing of specimens, and the misdiagnosis of type 1 sulci upon gross physical examination. The etiology of sulcus vocalis is still under debate. In the beginning of the 20th century, some investigators supported the congenital theory and attributed sulcus development to Darwin’s theory of evolution. This version of the congenital theory proposed that the accessory vocal fold reappears during the developmental period [2]. However, Bouchayer et al. [6] claimed that sulcus vocalis is a congenital disease
arising from developmental defects of the fourth and sixth branchial arches. Type 2 and type 3 sulci may be caused by ruptured epidermoid cysts. Bouchayer et al. [6] classified sulci as epidermoid cysts or mucosal bridges. As further evidence of this theory, the authors noted that the frequency of dysphonia existing from childhood was 55%. The alternative concept, that sulcus vocalis is an acquired condition, was proposed by Itoh [2]. In support of this study, described a cohort in which two-thirds of the patients had developed dysphonia after their 40s and argued that the rupture of bilateral cysts was an improbable etiology of bilateral sulcus vocalis. According to a report from the University of Wisconsin, sulcus vocalis was found in 48% of cases as a coincidental finding of histological examination after the resection of laryngeal cancer [4]. Upon pathological examination, increased fibrous tissue and vascularity were observed, which suggested that inflammation and irritation play a major role in pathogenesis. A number of previous studies have stated that chronic irritation, inflammation, and age play important roles in the emergence of sulcus vocalis [1,2,4,7]. In regard to the twins described here, dysphonia had been present since birth, supporting the congenital theory. The symmetric localization and similarities in the sulci in both patients further supports the congenital theory of sulcus development. A recent case report described the presence of sulcus vocalis in four members of a family, reinforcing the hypothesis of a genetic origin even in the absence of identified phenotypic or karyotypic alterations [8]. Consequently, the karyotype of our monozygotic twin patients may be important for investigating the genetic etiology of sulcus vocalis.
References [1] Ford CN, Inagi K, Khidr A, Bless DM, Gilchrist KW. Sulcus vocalis: a rational approach to diagnosis and management. Ann Otol Rhinol Laryngol 1996;105:189–200. [2] Giovanni A, Chanteret C, Lagier A. Sulcus vocalis: a review. Eur Arch Otorhinolaryngol 2007;264:337–44.
Z.A. Cakir et al. / Auris Nasus Larynx 37 (2010) 255–257 [3] Xu Z, Xia Z, Wang Z, Jiang F. Pediatric sulcus vocalis. Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2007;21(12):550–1. [4] Nakayama M, Ford CN, Brandenburg JH, Bless DM. Sulcus vocalis in laryngeal cancer: a histopathologic study. Laryngoscope 1994;104: 16–24. [5] Hsiung MW, Woo P, Wang HW, Su WY. A clinical classification and histopathological study of sulcus vocalis. Eur Arch Otorhinolaryngol 2000;257:466–8.
257
[6] Bouchayer M, Cornut G, Witzig E, Loire R, Roch JB, Bastian RW. Epidermoid cyst, sulci, and mucosal bridges of the true vocal cord: a report of 157 cases. Laryngoscope 1985;95:1087–94. [7] Hirano M, Yoshida T, Tanaka S, Hibi S. Sulcus vocalis: functional aspects. Ann Otol Rhinol Laryngol 1990;99:679–88. [8] Martins RH, Silva R, Ferreira DM, Dias NH. Sulcus vocalis: probable genetic etiology. Report of four cases in close relatives. Rev Bras Otorhinolaryngol 2007;73(4):573.