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Bilateral jugular bulb dehiscence in achondroplasia
International Journal of Pediatric Otorhinolaryngology Extra (2006) 1, 164—166
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CASE REPORT
Bilateral jugular bulb dehiscence in achondroplasia Jane Williams *, Alok Sharma, Peter Prinsley James Paget NHS Healthcare Trust, Lowestoft Road, Gorleston, Great Yarmouth, NR31 6LA, United Kingdom Received 5 November 2005; accepted 27 April 2006
KEYWORDS Achondroplasia; Middle ear; Hearing loss; Myringotomy
Summary This is the first reported case of bilateral jugular bulb dehiscence in achondroplasia. The girl was 2.5 years old at the time she was diagnosed with bilateral jugular bulb dehiscence. The suspicion of a prominent jugular bulb was raised at myringotomy. Computerised tomography showed the presence of bilateral jugular bulb dehiscences. Achondroplasia is a disorder of endochondral bone growth. Dehiscence of the jugular bulb occurs due to a defect of part of the petrous temporal bone, which develops by endochondral ossification. Thus, a higher incidence of jugular bulb dehiscence can expected to occur more commonly in achondroplasia. # 2006 Elsevier Ireland Ltd. All rights reserved.
1. Introduction In the literature there have been six previously reported cases of jugular bulb dehiscence in patients with achondroplasia. The age at the time of diagnosis was between 12 months and 20 years. In all cases the dehiscence was unilateral. Five cases were right sided and one was left sided. This case is therefore the first reported case of bilateral jugular bulb dehiscence in achondroplasia.
2. Case report A girl with achondroplasia was 2.5 years old at the time she was diagnosed with bilateral jugular bulb * Corresponding author. E-mail address: [email protected] (J. Williams).
dehiscence. At 11 months old she was diagnosed with achondroplasia. She was found to be heterozygote for the G380R g > a mutation in the FGFR3 gene, which is the commonest mutation for achondroplasia [3]. Neither of her parents had the mutation, indicating a spontaneous mutation, since the condition is autosommal dominant in its pattern of inheritance. Most cases occur due to a spontaneous mutation. The suspicion of a prominent jugular bulb was raised at myringotomy. This girl presented to the ENT clinic with developmental delay and a concern from her mother that she had reduced hearing. Examination revealed effusions bilaterally with a retracted tympanic membrane. Tympanograms showed flat traces bilaterally. There was a 40— 60 dB hearing loss on free field play audiometry. This girl was, therefore, booked for bilateral myringotomies and insertion of ventilation tubes.
1871-4048/$ — see front matter # 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.pedex.2006.04.009
Bilateral jugular bulb dehiscence in achondroplasia
165
Fig. 3 Coronal view showing bilateral jugular bulb dehiscence.
the right. Examination in clinic revealed bluish discolouration of the right tympanic membrane (Fig. 1). A CT scan confirmed the presence of a jugular bulb dehiscence on the right; however, it also showed a dehiscent jugular bulb on the left, as well (Figs. 2 and 3). The jugular bulb was more prominent on the right than on the left.
3. Discussion Fig. 1 Photograph of tympanic membrane showing bluish discolouration of jugular bulb dehiscence.
She was admitted and taken to theatre. The operating surgeon for the list was an ENTconsultant. A myringotomy was performed in an anterior/inferior position in the right tympanic membrane. On performing the myringotomy brisk bleeding occurred, with blood rapidly filling the aural speculum. The ear was packed with BIPP and the bleeding stopped. The rest of the operation was abandoned. One week later the patient was returned to theatre. The pack was removed and no further bleeding occurred. The patient was discharged the same day. The occurrence of bleeding highlighted a concern that this girl may have a jugular bulb dehiscence on
Fig. 2 Axial window showing bilateral jugular bulb dehiscence.
Findings consistent with otitis media with effusion in a child with achondroplasia are not unexpected. Previous literature has suggested that there is a higher incidence of otitis media in children with achondroplasia [4,5]. It has been suggested this is due to altered craniofacial morphology [6]. This suggestion makes it likely that myringotomies with the insertion of ventilation tubes would be performed on children with achondroplasia, at a similar, or probably greater rate, than the normal paediatric population. In two of the previously reported cases, as in this case, the diagnosis was suspected following brisk bleeding at myringotomy. The diagnosis was subsequently confirmed, as in our case, with CT scanning. Interestingly though, in one of these cases, uneventful myringotimes with insertion of ventilation tubes had been previously performed. In two other cases, where the diagnosis was finally suspected noting a bluish discolouration of the inferior tympanic membrane, previous myringotomies with insertion of ventilation tubes had also been performed, with an uneventful operative and post-operative course [1]. It should therefore be noted that, although performing a myringotomy has commonly led to the diagnosis of a jugular bulb dehiscence, performing what is felt to be a normal myringotomy, and insertion of ventilation tube, does not exclude the presence of a dehiscent jugular bulb in a patient. The remaining two cases were suspected following tympanotomy [1,2]. In the case of our child examination of her ears post-operatively did reveal bluish discolouration of the inferior aspect of the right tympanic membrane. However, it was only after a CT scan was performed that the bilateral nature of the jugular bulb dehiscence was discovered.
166 Subsequent to the discovery of bilateral jugular bulb dehiscence, it was decided to manage this child with bilateral hearing aids. Hearing aids are still a safe and effective treatment for hearing loss due to otitis media with effusion. This may prove particularly to be the case for children with achondroplasia, due to the increased potential for jugular bulb dehiscence compared to the normal paediatric population. One paper has also suggested that hearing loss may be commonly mixed in children with achondroplasia [7]. The majority of the previously reported cases have been right sided (five of the previous six cases) [1,2]. In this case, although it is bilateral, the jugular bulb dehiscence is more prominent on the right. This is consistent with previous literature looking at high jugular bulbs in temporal bones. It has been reported for them to occur more commonly on the right [8,9]. The majority of cases have also been unilateral. An explanation proposed for the preponderance on the right is that, in roughly three quarters of individuals, the right jugular vein and transverse sinus are larger on the right [10]. An increased incidence of jugular bulb dehiscence has been reported in children with achondroplasia [1]. An explanation for this lies in the nature of the disorder of achondroplasia. Achondroplasia is a disorder of endochondral bone growth. Dehiscence of the jugular bulb occurs due to a defect of the bony plate that normally separates the middle ear from the jugular bulb [9]. This indicates a defect of part of the petrous portion of the temporal bone, which develops by endochondral ossification [7]; thus, a defect can be expected to occur more commonly in achondroplasia. The concern in this case, and in those previously reported, is that diagnosis was only made following at least one operation. In the majority of cases it
J. Williams et al. was the operative procedure that led to the diagnosis. This suggests that there needs to be a higher index of suspicion of jugular bulb dehiscence in patients with achondroplasia, especially when middle ear surgery is contemplated. In conclusion, children with achondroplasia have a higher risk of jugular bulb dehiscence; thus, extra care should be taken when performing middle ear surgery, including simple myringotomies.
References [1] R.M. Pauli, P. Modaff, Jugular bulb dehiscence in achondroplasia, Int. J. Pediatr. Otorhinolaryngol. 48 (1999) 169—174. [2] J.M. West, B.C. Bandy, B.W. Jafek, Aberrant jugular bulb in the middle ear cavity, Arch. Otolaryngol. 100 (1974) 370— 372. [3] G.A. Bellus, T.W. Heffernon, R.I. Ortiz de Luna, J.T. Hecht, W.A. Horton, M. Machado, et al., Achondroplasia is defined by recurrent G380R mutations of FGFR3, Am. J. Hum. Genet. 56 (1995) 368—373. [4] R.F. Gorlin, J.J. Pindborg, M.M. Cohen, Syndromes of the Head and Neck, McGraw-Hill, New York, 1976. [5] M.M. Cohen, Dysmorphic syndromes with craniofacial manifestations, in: R.E. Stewart, G. Prescott (Eds.), Oral Facial Genetics, Mosby, St. Louis, 1976, pp. 523—526. [6] L. Glass, I. Shapiro, S.E. Hodge, L. Bergstrom, D.L. Rimoin, Audiological findings of patients with achondroplasia, Int. J. Pediatr. Otorhinolaryngol. 3 (1981) 129—135. [7] S.R. Cobb, M. Shohat, C.M. Mehringer, R. Lachman, CTof the temporal bone in achondroplasia, Am. J. Neuroradiol. 9 (1988) 1195—1199. [8] D.-J. Lin, C.-J. Hsu, K.-N. Lin, The high jugular bulb: report of five cases and a review of the literature, J. Formos. Med. Assoc. 92 (1993) 745—750. [9] S.B. Overton, F.N. Ritter, A high placed jugular bulb in the middle ear: a clinical and temporal bone study, Laryngoscope 83 (1973) 1986—1991. [10] T. Gejrot, Retrograde jugulography in the diagnosis of abnormality of the superior bulb of the internal jugular vein, Arch. Otolaryngol. 57 (1964) 177—180.
www.elsevier.com/locate/ijporl
CASE REPORT
Bilateral jugular bulb dehiscence in achondroplasia Jane Williams *, Alok Sharma, Peter Prinsley James Paget NHS Healthcare Trust, Lowestoft Road, Gorleston, Great Yarmouth, NR31 6LA, United Kingdom Received 5 November 2005; accepted 27 April 2006
KEYWORDS Achondroplasia; Middle ear; Hearing loss; Myringotomy
Summary This is the first reported case of bilateral jugular bulb dehiscence in achondroplasia. The girl was 2.5 years old at the time she was diagnosed with bilateral jugular bulb dehiscence. The suspicion of a prominent jugular bulb was raised at myringotomy. Computerised tomography showed the presence of bilateral jugular bulb dehiscences. Achondroplasia is a disorder of endochondral bone growth. Dehiscence of the jugular bulb occurs due to a defect of part of the petrous temporal bone, which develops by endochondral ossification. Thus, a higher incidence of jugular bulb dehiscence can expected to occur more commonly in achondroplasia. # 2006 Elsevier Ireland Ltd. All rights reserved.
1. Introduction In the literature there have been six previously reported cases of jugular bulb dehiscence in patients with achondroplasia. The age at the time of diagnosis was between 12 months and 20 years. In all cases the dehiscence was unilateral. Five cases were right sided and one was left sided. This case is therefore the first reported case of bilateral jugular bulb dehiscence in achondroplasia.
2. Case report A girl with achondroplasia was 2.5 years old at the time she was diagnosed with bilateral jugular bulb * Corresponding author. E-mail address: [email protected] (J. Williams).
dehiscence. At 11 months old she was diagnosed with achondroplasia. She was found to be heterozygote for the G380R g > a mutation in the FGFR3 gene, which is the commonest mutation for achondroplasia [3]. Neither of her parents had the mutation, indicating a spontaneous mutation, since the condition is autosommal dominant in its pattern of inheritance. Most cases occur due to a spontaneous mutation. The suspicion of a prominent jugular bulb was raised at myringotomy. This girl presented to the ENT clinic with developmental delay and a concern from her mother that she had reduced hearing. Examination revealed effusions bilaterally with a retracted tympanic membrane. Tympanograms showed flat traces bilaterally. There was a 40— 60 dB hearing loss on free field play audiometry. This girl was, therefore, booked for bilateral myringotomies and insertion of ventilation tubes.
1871-4048/$ — see front matter # 2006 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.pedex.2006.04.009
Bilateral jugular bulb dehiscence in achondroplasia
165
Fig. 3 Coronal view showing bilateral jugular bulb dehiscence.
the right. Examination in clinic revealed bluish discolouration of the right tympanic membrane (Fig. 1). A CT scan confirmed the presence of a jugular bulb dehiscence on the right; however, it also showed a dehiscent jugular bulb on the left, as well (Figs. 2 and 3). The jugular bulb was more prominent on the right than on the left.
3. Discussion Fig. 1 Photograph of tympanic membrane showing bluish discolouration of jugular bulb dehiscence.
She was admitted and taken to theatre. The operating surgeon for the list was an ENTconsultant. A myringotomy was performed in an anterior/inferior position in the right tympanic membrane. On performing the myringotomy brisk bleeding occurred, with blood rapidly filling the aural speculum. The ear was packed with BIPP and the bleeding stopped. The rest of the operation was abandoned. One week later the patient was returned to theatre. The pack was removed and no further bleeding occurred. The patient was discharged the same day. The occurrence of bleeding highlighted a concern that this girl may have a jugular bulb dehiscence on
Fig. 2 Axial window showing bilateral jugular bulb dehiscence.
Findings consistent with otitis media with effusion in a child with achondroplasia are not unexpected. Previous literature has suggested that there is a higher incidence of otitis media in children with achondroplasia [4,5]. It has been suggested this is due to altered craniofacial morphology [6]. This suggestion makes it likely that myringotomies with the insertion of ventilation tubes would be performed on children with achondroplasia, at a similar, or probably greater rate, than the normal paediatric population. In two of the previously reported cases, as in this case, the diagnosis was suspected following brisk bleeding at myringotomy. The diagnosis was subsequently confirmed, as in our case, with CT scanning. Interestingly though, in one of these cases, uneventful myringotimes with insertion of ventilation tubes had been previously performed. In two other cases, where the diagnosis was finally suspected noting a bluish discolouration of the inferior tympanic membrane, previous myringotomies with insertion of ventilation tubes had also been performed, with an uneventful operative and post-operative course [1]. It should therefore be noted that, although performing a myringotomy has commonly led to the diagnosis of a jugular bulb dehiscence, performing what is felt to be a normal myringotomy, and insertion of ventilation tube, does not exclude the presence of a dehiscent jugular bulb in a patient. The remaining two cases were suspected following tympanotomy [1,2]. In the case of our child examination of her ears post-operatively did reveal bluish discolouration of the inferior aspect of the right tympanic membrane. However, it was only after a CT scan was performed that the bilateral nature of the jugular bulb dehiscence was discovered.
166 Subsequent to the discovery of bilateral jugular bulb dehiscence, it was decided to manage this child with bilateral hearing aids. Hearing aids are still a safe and effective treatment for hearing loss due to otitis media with effusion. This may prove particularly to be the case for children with achondroplasia, due to the increased potential for jugular bulb dehiscence compared to the normal paediatric population. One paper has also suggested that hearing loss may be commonly mixed in children with achondroplasia [7]. The majority of the previously reported cases have been right sided (five of the previous six cases) [1,2]. In this case, although it is bilateral, the jugular bulb dehiscence is more prominent on the right. This is consistent with previous literature looking at high jugular bulbs in temporal bones. It has been reported for them to occur more commonly on the right [8,9]. The majority of cases have also been unilateral. An explanation proposed for the preponderance on the right is that, in roughly three quarters of individuals, the right jugular vein and transverse sinus are larger on the right [10]. An increased incidence of jugular bulb dehiscence has been reported in children with achondroplasia [1]. An explanation for this lies in the nature of the disorder of achondroplasia. Achondroplasia is a disorder of endochondral bone growth. Dehiscence of the jugular bulb occurs due to a defect of the bony plate that normally separates the middle ear from the jugular bulb [9]. This indicates a defect of part of the petrous portion of the temporal bone, which develops by endochondral ossification [7]; thus, a defect can be expected to occur more commonly in achondroplasia. The concern in this case, and in those previously reported, is that diagnosis was only made following at least one operation. In the majority of cases it
J. Williams et al. was the operative procedure that led to the diagnosis. This suggests that there needs to be a higher index of suspicion of jugular bulb dehiscence in patients with achondroplasia, especially when middle ear surgery is contemplated. In conclusion, children with achondroplasia have a higher risk of jugular bulb dehiscence; thus, extra care should be taken when performing middle ear surgery, including simple myringotomies.
References [1] R.M. Pauli, P. Modaff, Jugular bulb dehiscence in achondroplasia, Int. J. Pediatr. Otorhinolaryngol. 48 (1999) 169—174. [2] J.M. West, B.C. Bandy, B.W. Jafek, Aberrant jugular bulb in the middle ear cavity, Arch. Otolaryngol. 100 (1974) 370— 372. [3] G.A. Bellus, T.W. Heffernon, R.I. Ortiz de Luna, J.T. Hecht, W.A. Horton, M. Machado, et al., Achondroplasia is defined by recurrent G380R mutations of FGFR3, Am. J. Hum. Genet. 56 (1995) 368—373. [4] R.F. Gorlin, J.J. Pindborg, M.M. Cohen, Syndromes of the Head and Neck, McGraw-Hill, New York, 1976. [5] M.M. Cohen, Dysmorphic syndromes with craniofacial manifestations, in: R.E. Stewart, G. Prescott (Eds.), Oral Facial Genetics, Mosby, St. Louis, 1976, pp. 523—526. [6] L. Glass, I. Shapiro, S.E. Hodge, L. Bergstrom, D.L. Rimoin, Audiological findings of patients with achondroplasia, Int. J. Pediatr. Otorhinolaryngol. 3 (1981) 129—135. [7] S.R. Cobb, M. Shohat, C.M. Mehringer, R. Lachman, CTof the temporal bone in achondroplasia, Am. J. Neuroradiol. 9 (1988) 1195—1199. [8] D.-J. Lin, C.-J. Hsu, K.-N. Lin, The high jugular bulb: report of five cases and a review of the literature, J. Formos. Med. Assoc. 92 (1993) 745—750. [9] S.B. Overton, F.N. Ritter, A high placed jugular bulb in the middle ear: a clinical and temporal bone study, Laryngoscope 83 (1973) 1986—1991. [10] T. Gejrot, Retrograde jugulography in the diagnosis of abnormality of the superior bulb of the internal jugular vein, Arch. Otolaryngol. 57 (1964) 177—180.