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Atypical presentation of geniculate ganglion venous malformation in a child: Conductive hearing loss without facial weakness
International Journal of Pediatric Otorhinolaryngology 76 (2012) 1214–1216
Contents lists available at SciVerse ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Case report
Atypical presentation of geniculate ganglion venous malformation in a child: Conductive hearing loss without facial weakness Julie A. Ames, Jessica R. Levi, Douglas R. Johnston, Colin A. Drake, Thomas O. Willcox, Robert C. O’Reilly * Alfred I. duPont Hospital for Children, Wilmington, DE, United States
A R T I C L E I N F O
A B S T R A C T
Article history: Received 6 February 2012 Accepted 18 April 2012 Available online 17 May 2012
We describe an unusual presentation of geniculate ganglion venous malformation, a rare facial nerve lesion, emphasizing the importance of the differential diagnosis, imaging characteristics, and controversies in management. A child presented with moderate right-sided conductive hearing loss and a House-Brackmann grade I facial nerve function bilaterally. Computed tomography and magnetic resonance imaging showed a mass demonstrating features consistent with a geniculate ganglion venous malformation. To our knowledge, this is the first pediatric case of geniculate ganglion venous malformation presenting solely with conductive hearing loss. Proper management requires differentiating this condition from other geniculate and temporal bone lesions. ß 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Facial nerve Geniculate ganglion Venous malformation
1. Introduction
3. Case report
Geniculate ganglion venous malformation (GGVM) is an extremely rare temporal bone lesion accounting for 0.7% of all vascular lesions in this location [1]. These lesions have historically been referred to as geniculate ganglion hemangiomas, but in recent published literature, reexamination of the histopathology suggests venous malformation is a more accurate classification [2]. Typically, vascular lesions arise from either the geniculate ganglion (GG), producing facial weakness, or from the internal auditory canal (IAC), resulting in sensorineural hearing loss (SNHL). Lesions arising from the GG may encase and erode the ossicular chain, producing a conductive hearing loss (CHL). It is unusual for these lesions to progress to a size that produces CHL without some degree of facial nerve weakness because even small lesions often produce facial nerve paresis or palsy. We present the case of a GGVM that had encased the ossicular chain in the epitympanum, producing a CHL without facial weakness. Radiographic recognition of this lesion and differentiation from the far more common cholesteatoma is vital to guiding management.
A nine-year-old otherwise healthy male presented to our clinic after a moderate CHL was discovered in his right ear during an audiologic screening due to parental concerns of hearing loss over the prior year. There was a remote history of otitis media, which was not associated with hearing loss, and there was no history of otologic surgery. Physical examination revealed no abnormalities of the tympanic membrane or middle ear space. Facial nerve function was House Brackmann (HB) I/VI. A repeat audiologic evaluation one month later confirmed a unilateral moderate CHL with absent ipsilateral otoacoustic emissions. The tympanogram was type As. Computerized tomographic scans of the temporal bone demonstrated an expansile mass with internal calcifications and a honeycomb appearance originating from the area of the GG. The facial canal at the GG and tympanic segment was mildly enlarged with abnormal demineralization. The mass was centered in the epitympanum around the ossicular heads and extended inferiorly to the mesotympanum, medial to the body of the malleus. The mass eroded the body of the incus and obscured the lenticular process and the stapes superstructure. Partial obstruction of the aditus ad antrum resulted in subtotal mastoid air cell opacification. Subsequent MRI showed mild enhancement on T1-weighted postcontrast images of soft tissue within the right epitympanum and mesotympanum, as well as a stable right mastoid effusion.
2. Materials and methods A systematic review of the patient medical record including clinic notes, audiometric findings, computed tomography (CT), and magnetic resonance imaging (MRI) data was performed. * Corresponding author at: Division of Pediatric Otolaryngology, Alfred I. duPont Hospital for Children, P.O. Box 269, Wilmington, DE 19899, United States. Tel.: +1 302 651 5829; fax: +1 302 651 6410. E-mail address: [email protected] (R.C. O’Reilly). 0165-5876/$ – see front matter ß 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijporl.2012.04.021
4. Discussion Symptoms of GGVM may include facial nerve weakness, facial spasm or twitching, tinnitus, facial pain, vestibular disturbance,
J.A. Ames et al. / International Journal of Pediatric Otorhinolaryngology 76 (2012) 1214–1216
hearing loss, and epiphora or xerophthalmia [3]. The earliest symptom of GGVM is reportedly be facial nerve paresis or palsy. In the largest case series to date by Semaan et al., 94% (17 out of 18) of patients presented with facial nerve dysfunction [4]. Typically, facial nerve weakness is slowly progressive or recurrent in nature; this weakness necessitates imaging to rule out a lesion. However, hearing loss is the second most common symptom in the adult literature. Piccirillo et al. reported 10 patients with temporal bone vascular lesions, with an age range of 38–58 years. While four of the 10 patients had an HB I/VI at the time of diagnosis, the remaining six patients had an HB III/VI or worse. In addition, 70% of the patients presented with hearing loss, including one patient with CHL, four patients with SNHL, and two patients with total deafness [5]. In the series by Semaan et al., 22% of patients had some degree of hearing loss. There are very few cases of GG venous malformations reported in the literature and they are typically described as hemangiomas. However, the pathophysiology of this lesion has been shown to be more consistent with a venous vascular malformation than that of a hemangioma. Infantile hemangiomas are benign vascular tumors resulting from cellular hyperplasia, and have a characteristic period of growth followed by involution in early-to-mid childhood. In contrast, vascular malformations are errors of vascular morphogenesis that develop in utero, and persist after birth with a pattern of proportional growth [2]. In fact, Benoit et al. suggested that the designation of facial nerve hemangioma be replaced by the more accurate term ‘‘venous vascular malformation of the facial nerve.’’ Indeed, these lesions are thought to arise from the vascular network that surrounds the GG. This network derives its blood supply from the petrosal branch of the middle meningeal artery [6]. The case series by Benoit et al. included seven patients with vascular malformations that were resected from the facial nerve. These lesions lacked immunohistochemical staining for glucose transporter protein isoform 1 (GLUT1); Lewis Y antigen (LeY), a sensitive and specific marker of infantile hemangioma; and podoplanin staining utilizing D2-40 antibody, an indicator of lymphatic differentiation. The hematoxylin and eosin histopathology of these vascular lesions uniformly revealed dilated vessels with scant smooth muscle, no internal elastic laminae, and a mitotically quiescent appearance consistent with venous origin. Presentation of GGVM in the pediatric age group is very rare. The majority of lesions reportedly occur in the fourth and fifth decade of life. A case study by Fierek et al. presented a large vascular lesion in a six-year-old child with a history of recurrent otitis media and mild CHL [7]. This lesion occupied the mastoid and tympanic cavity without producing facial nerve weakness. The anatomic origin of the lesion is unclear, but it does not appear to have arisen from the GG. Fierek et al. cite two other case reports of pediatric patients with hemangiomas involving the mastoid and petrous apex (12 and 14 years of age) and conclude that the occurrence of these lesions in children favors the hypothesis of hereditary vascular malformation [1,8]. Based on this finding, they state that it appears that intratemporal hemangiomas in sites
1215
other than the GG and IAC may develop preferentially in children. Our case report does not support this conclusion. Since these lesions appear to be congenital by their histology and pathophysiology, it is more likely that they arise from the GG in children but take years to decades to infiltrate the facial nerve to produce weakness or to envelop the ossicular chain sufficiently to produce noticeable hearing loss. Indeed, it is possible that many of these lesions are extremely indolent in their growth pattern or do not progress. The differential diagnosis of a mass in the temporal bone includes facial nerve schwannoma, cholesteatoma, meningioma, and metastatic lesions [3]. A GGVM in a child with a CHL and a lesion in the anterosuperior pitympanum must be distinguished from a congenital cholesteatoma. Successfully making this distinction is vital to appropriate management. On CT, congenital cholesteatomas typically arise from the anterosuperior quadrant of the tympanum and produce smoothly marginated erosion of the surrounding bone, including the scutum, with interruption of the ossicles. In contrast, GGVM is typically centered upon the GG and produces an area of irregular bony erosion with a characteristic ‘‘moth-eaten’’ appearance and intralesional calcifications. On MRI, GGVM is often hyperintense on T2-weighted images and has enhancement with gadolinium on T1-weighted images [9]. A cholesteatoma has no contrast enhancement with CT or MRI, and is hypointense on T1-weighted images and hyperintense on T2weighted images (Table 1). Further, a facial nerve schwannoma has smoothly marginated edges without internal calcifications on CT, has enhancement with gadolinium on T1-weighted images, and is hyperintense on T2-weighted images [3,9]. The imaging appearance in our patient is not pathognomonic, but is most consistent with a venous vascular malformation of the GG because of the location, the expansion of the facial canal, the mild enhancement seen on T1 post-contrast images, as well as a stable right mastoid effusion and the calcifications. Congenital cholesteatoma was a strong consideration in the differential diagnosis because the lesion was dense on CT, and was located near the attic. Presentation at age eight years, however, is unlikely for a congenital cholesteatoma that shows minimal bony destruction on CT (Fig. 1). In addition, the presence of intralesional calcifications seen on CT makes schwannoma a less likely diagnosis. Management of GGVM remains controversial and difficult. Although several theories have evolved to explain the decline of facial nerve function, including nerve compression, ‘‘vascular steal’’ from the arterial supply of the nerve, and infiltration of the nerve, the infiltrative nature of the lesion often requires resection of the involved segment of facial nerve with grafting [3]. The best possible facial nerve function post-grafting is HB III/VI. Thus, the function of the nerve preoperatively must be considered in light of the expected postoperative deficit. Indeed, the feasibility of complete separation of the vascular malformation from the facial nerve is questionable given the findings of Isaacson et al. who noted that in the majority of cases (five of six), the facial nerve had to be resected for complete removal [10]. In these cases, the vascular lesions were found to be infiltrating the nerve. Thus
Table 1 Comparison of clinical and diagnostic features of GGVM and cholesteatoma [1–5,9].
GGVM
Audiogram physical exam
Location
CT
MRI
Conductive hearing loss Facial paralysis, unilateral hearing loss
Centered upon the geniculate ganglion
Intralesional calcifications and bony spicules, irregular borders
T2-weighted hyperintense, T1-weighted post-gadolinium enhancement
Anterosuperior Conductive hearing loss T2-weighted hyperintense, T1-weighted Smooth, marginated bony erosion mesotympanum mass Facial paralysis unilateral hypointense; no post-gadolinium enhancement hearing loss CT, computed tomography; GGVM, geniculate ganglion venous malformation; and MRI, magnetic resonance imaging. Cholesteatoma
1216
J.A. Ames et al. / International Journal of Pediatric Otorhinolaryngology 76 (2012) 1214–1216
Fig. 1. Congenital cholesteatoma (A and B) and GGVM (C and D). Axial computed tomography scan (A and B) shows a soft tissue opacification in the anterosuperior quadrant of the tympanum with characteristic smoothly marginated erosion of the surrounding bone with interruption of the ossicles, consistent with a congenital cholesteatoma. In contrast, computed tomographic imaging suggestive of GGVM includes a lesion centered upon the geniculate ganglion that produces an area of irregular bony erosion with a characteristic ‘‘moth-eaten’’ appearance and intralesional calcifications (C). Magnetic resonance imaging of our patient (D) shows enhancement with gadolinium on T1weighted images, typical of GGVM. GGVM, geniculate ganglion vascular malformation.
Isaacson et al. recommend that surgical excision be deferred until the facial nerve function has declined to HB III/VI or worse. Semaan et al. found that the electromyographic findings in patients with this GGVM showed a mixed pattern of degeneration and regeneration, with simultaneous presence of fibrillation potentials and polyphasic action potentials [4]. In the series by Semaan et al., although six of 18 patients had excision of the lesion without nerve sacrifice, the patients who did require a nerve graft had worse postoperative facial nerve function. Therefore, early resection of the lesion to prevent irreversible nerve degeneration may not be warranted. The traditional management of venous malformations of the head and neck includes observation, sclerotherapy, surgical resection, and laser treatments. Unlike the treatment strategy for hemangiomas, which have characteristic periods of growth, then involution, venous malformations are managed with the expectation that they will grow in proportion with the patient. The frequently multi-septated, complex structure of head and neck venous malformations often results in excessive blood loss and potential neurologic sequelae during surgery, which is why observation, sclerotherapy, and laser treatment are more commonly used. Injection sclerotherapy poses a risky option in which sclerosants could cause significant ototoxicity or endarterial labyrinthine damage. Intra-lesional steroid injection is a viable treatment option for carefully selected hemangiomas of the face, orbit, and airway, but is likely of low efficacy in venous malformations given the low proliferative state. The prospect of intratympanic steroids, while labyrinthine-sparing, is likewise of seemingly low therapeutic benefit. Lastly, the use of a carbon dioxide or YAG laser (time-tested in otologic surgery) could be contemplated for treating the portion of the malformation surrounding the ossicles to relieve the compressive effect. Attempts to laser the component adjacent to or involving the geniculate ganglion would result in direct damage to the facial nerve. In the case presented, surgical excision is a probable eventuality given the propensity for these GGVMs to slowly enlarge and destroy facial nerve function and worsen hearing.
5. Conclusion Geniculate ganglion venous malformations are rare lesions arising within the temporal bone. In the adult literature, the primary clinical finding of a GGVM is progressive facial nerve weakness; however, our patient presented with CHL. Therefore, when evaluating a patient with a temporal bone lesion involving the GG, it is important to be vigilant for the possibility of a GGVM presenting with conductive hearing loss but without any facial nerve weakness. Careful evaluation of the imaging, including CT and MRI, will assist in distinguishing a GGVM from other temporal bone lesions, which is vital for correct preoperative diagnosis and proper medical or surgical management. Conflicts of interest The authors have no funding or conflicts of interest to disclose. References [1] C.A. Mangham, J.N. Carberry, D.E. Brackmann, Management of intratemporal vascular tumors, Laryngoscope 91 (1981) 867–876. [2] M.M. Benoit, P.E. North, M.J. McKenna, M.C. Mihm, M.M. Johnson, M.J. Cunningham, Facial nerve hemangiomas: vascular tumors or malformations? Otolaryngol. Head Neck Surg. 142 (2010) 108–114. [3] H.A. Arts, Geniculate hemangioma, in: R.K. Jackler, C.L.W. Driscoll (Eds.), Tumors of the Ear and Temporal Bone, Lippincot, Williams & Wilkins, Philadelphia, 2000, pp. 290–302. [4] M.T. Semaan, W.H. Slattery, D.E. Brackmann, Geniculate ganglion hemangiomas: clinical results and long-term follow-up, Otol. Neurotol. 31 (2010) 665–670. [5] E. Piccirillo, M. Agarwal, M.S. Rohit, T. Khrais, M. Sanna, Management of temporal bone hemangiomas, Ann. Otol. Rhinol. Laryngol. 113 (2004) 431–437. [6] H. El-Khouly, J. Fernandez-Miranda, A.L. Rhoton Jr., Blood supply of the facial nerve in the middle fossa: the petrosal artery, Neurosurgery 62 (2008) ONS297– ONS303 (discussion ONS303–ONS304). [7] O. Fierek, R. Laskawi, E. Kunze, Large intraossesous hemangioma of the temporal bone in a child, Ann. Otol. Rhinol. Laryngol. 113 (2004) 394–398. [8] E. Kley, Das intraossare angiom des schlafenbeines, eine seltene erkrankung,(Intraosseous angioma of the temporal bone—a rare disease), Z. Laryngol. Rhinol. Otol. 51 (1972) 824–829. [9] V. Achilli, S. Mignosi, Facial nerve hemangioma, Otol. Neurotol. 23 (2002) 1003–1004. [10] B. Isaacson, S.A. Telian, P.E. McKeever, H.A. Arts, Hemangiomas of the geniculate ganglion, Otol. Neurotol. 26 (2005) 796–802.
Contents lists available at SciVerse ScienceDirect
International Journal of Pediatric Otorhinolaryngology journal homepage: www.elsevier.com/locate/ijporl
Case report
Atypical presentation of geniculate ganglion venous malformation in a child: Conductive hearing loss without facial weakness Julie A. Ames, Jessica R. Levi, Douglas R. Johnston, Colin A. Drake, Thomas O. Willcox, Robert C. O’Reilly * Alfred I. duPont Hospital for Children, Wilmington, DE, United States
A R T I C L E I N F O
A B S T R A C T
Article history: Received 6 February 2012 Accepted 18 April 2012 Available online 17 May 2012
We describe an unusual presentation of geniculate ganglion venous malformation, a rare facial nerve lesion, emphasizing the importance of the differential diagnosis, imaging characteristics, and controversies in management. A child presented with moderate right-sided conductive hearing loss and a House-Brackmann grade I facial nerve function bilaterally. Computed tomography and magnetic resonance imaging showed a mass demonstrating features consistent with a geniculate ganglion venous malformation. To our knowledge, this is the first pediatric case of geniculate ganglion venous malformation presenting solely with conductive hearing loss. Proper management requires differentiating this condition from other geniculate and temporal bone lesions. ß 2012 Elsevier Ireland Ltd. All rights reserved.
Keywords: Facial nerve Geniculate ganglion Venous malformation
1. Introduction
3. Case report
Geniculate ganglion venous malformation (GGVM) is an extremely rare temporal bone lesion accounting for 0.7% of all vascular lesions in this location [1]. These lesions have historically been referred to as geniculate ganglion hemangiomas, but in recent published literature, reexamination of the histopathology suggests venous malformation is a more accurate classification [2]. Typically, vascular lesions arise from either the geniculate ganglion (GG), producing facial weakness, or from the internal auditory canal (IAC), resulting in sensorineural hearing loss (SNHL). Lesions arising from the GG may encase and erode the ossicular chain, producing a conductive hearing loss (CHL). It is unusual for these lesions to progress to a size that produces CHL without some degree of facial nerve weakness because even small lesions often produce facial nerve paresis or palsy. We present the case of a GGVM that had encased the ossicular chain in the epitympanum, producing a CHL without facial weakness. Radiographic recognition of this lesion and differentiation from the far more common cholesteatoma is vital to guiding management.
A nine-year-old otherwise healthy male presented to our clinic after a moderate CHL was discovered in his right ear during an audiologic screening due to parental concerns of hearing loss over the prior year. There was a remote history of otitis media, which was not associated with hearing loss, and there was no history of otologic surgery. Physical examination revealed no abnormalities of the tympanic membrane or middle ear space. Facial nerve function was House Brackmann (HB) I/VI. A repeat audiologic evaluation one month later confirmed a unilateral moderate CHL with absent ipsilateral otoacoustic emissions. The tympanogram was type As. Computerized tomographic scans of the temporal bone demonstrated an expansile mass with internal calcifications and a honeycomb appearance originating from the area of the GG. The facial canal at the GG and tympanic segment was mildly enlarged with abnormal demineralization. The mass was centered in the epitympanum around the ossicular heads and extended inferiorly to the mesotympanum, medial to the body of the malleus. The mass eroded the body of the incus and obscured the lenticular process and the stapes superstructure. Partial obstruction of the aditus ad antrum resulted in subtotal mastoid air cell opacification. Subsequent MRI showed mild enhancement on T1-weighted postcontrast images of soft tissue within the right epitympanum and mesotympanum, as well as a stable right mastoid effusion.
2. Materials and methods A systematic review of the patient medical record including clinic notes, audiometric findings, computed tomography (CT), and magnetic resonance imaging (MRI) data was performed. * Corresponding author at: Division of Pediatric Otolaryngology, Alfred I. duPont Hospital for Children, P.O. Box 269, Wilmington, DE 19899, United States. Tel.: +1 302 651 5829; fax: +1 302 651 6410. E-mail address: [email protected] (R.C. O’Reilly). 0165-5876/$ – see front matter ß 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijporl.2012.04.021
4. Discussion Symptoms of GGVM may include facial nerve weakness, facial spasm or twitching, tinnitus, facial pain, vestibular disturbance,
J.A. Ames et al. / International Journal of Pediatric Otorhinolaryngology 76 (2012) 1214–1216
hearing loss, and epiphora or xerophthalmia [3]. The earliest symptom of GGVM is reportedly be facial nerve paresis or palsy. In the largest case series to date by Semaan et al., 94% (17 out of 18) of patients presented with facial nerve dysfunction [4]. Typically, facial nerve weakness is slowly progressive or recurrent in nature; this weakness necessitates imaging to rule out a lesion. However, hearing loss is the second most common symptom in the adult literature. Piccirillo et al. reported 10 patients with temporal bone vascular lesions, with an age range of 38–58 years. While four of the 10 patients had an HB I/VI at the time of diagnosis, the remaining six patients had an HB III/VI or worse. In addition, 70% of the patients presented with hearing loss, including one patient with CHL, four patients with SNHL, and two patients with total deafness [5]. In the series by Semaan et al., 22% of patients had some degree of hearing loss. There are very few cases of GG venous malformations reported in the literature and they are typically described as hemangiomas. However, the pathophysiology of this lesion has been shown to be more consistent with a venous vascular malformation than that of a hemangioma. Infantile hemangiomas are benign vascular tumors resulting from cellular hyperplasia, and have a characteristic period of growth followed by involution in early-to-mid childhood. In contrast, vascular malformations are errors of vascular morphogenesis that develop in utero, and persist after birth with a pattern of proportional growth [2]. In fact, Benoit et al. suggested that the designation of facial nerve hemangioma be replaced by the more accurate term ‘‘venous vascular malformation of the facial nerve.’’ Indeed, these lesions are thought to arise from the vascular network that surrounds the GG. This network derives its blood supply from the petrosal branch of the middle meningeal artery [6]. The case series by Benoit et al. included seven patients with vascular malformations that were resected from the facial nerve. These lesions lacked immunohistochemical staining for glucose transporter protein isoform 1 (GLUT1); Lewis Y antigen (LeY), a sensitive and specific marker of infantile hemangioma; and podoplanin staining utilizing D2-40 antibody, an indicator of lymphatic differentiation. The hematoxylin and eosin histopathology of these vascular lesions uniformly revealed dilated vessels with scant smooth muscle, no internal elastic laminae, and a mitotically quiescent appearance consistent with venous origin. Presentation of GGVM in the pediatric age group is very rare. The majority of lesions reportedly occur in the fourth and fifth decade of life. A case study by Fierek et al. presented a large vascular lesion in a six-year-old child with a history of recurrent otitis media and mild CHL [7]. This lesion occupied the mastoid and tympanic cavity without producing facial nerve weakness. The anatomic origin of the lesion is unclear, but it does not appear to have arisen from the GG. Fierek et al. cite two other case reports of pediatric patients with hemangiomas involving the mastoid and petrous apex (12 and 14 years of age) and conclude that the occurrence of these lesions in children favors the hypothesis of hereditary vascular malformation [1,8]. Based on this finding, they state that it appears that intratemporal hemangiomas in sites
1215
other than the GG and IAC may develop preferentially in children. Our case report does not support this conclusion. Since these lesions appear to be congenital by their histology and pathophysiology, it is more likely that they arise from the GG in children but take years to decades to infiltrate the facial nerve to produce weakness or to envelop the ossicular chain sufficiently to produce noticeable hearing loss. Indeed, it is possible that many of these lesions are extremely indolent in their growth pattern or do not progress. The differential diagnosis of a mass in the temporal bone includes facial nerve schwannoma, cholesteatoma, meningioma, and metastatic lesions [3]. A GGVM in a child with a CHL and a lesion in the anterosuperior pitympanum must be distinguished from a congenital cholesteatoma. Successfully making this distinction is vital to appropriate management. On CT, congenital cholesteatomas typically arise from the anterosuperior quadrant of the tympanum and produce smoothly marginated erosion of the surrounding bone, including the scutum, with interruption of the ossicles. In contrast, GGVM is typically centered upon the GG and produces an area of irregular bony erosion with a characteristic ‘‘moth-eaten’’ appearance and intralesional calcifications. On MRI, GGVM is often hyperintense on T2-weighted images and has enhancement with gadolinium on T1-weighted images [9]. A cholesteatoma has no contrast enhancement with CT or MRI, and is hypointense on T1-weighted images and hyperintense on T2weighted images (Table 1). Further, a facial nerve schwannoma has smoothly marginated edges without internal calcifications on CT, has enhancement with gadolinium on T1-weighted images, and is hyperintense on T2-weighted images [3,9]. The imaging appearance in our patient is not pathognomonic, but is most consistent with a venous vascular malformation of the GG because of the location, the expansion of the facial canal, the mild enhancement seen on T1 post-contrast images, as well as a stable right mastoid effusion and the calcifications. Congenital cholesteatoma was a strong consideration in the differential diagnosis because the lesion was dense on CT, and was located near the attic. Presentation at age eight years, however, is unlikely for a congenital cholesteatoma that shows minimal bony destruction on CT (Fig. 1). In addition, the presence of intralesional calcifications seen on CT makes schwannoma a less likely diagnosis. Management of GGVM remains controversial and difficult. Although several theories have evolved to explain the decline of facial nerve function, including nerve compression, ‘‘vascular steal’’ from the arterial supply of the nerve, and infiltration of the nerve, the infiltrative nature of the lesion often requires resection of the involved segment of facial nerve with grafting [3]. The best possible facial nerve function post-grafting is HB III/VI. Thus, the function of the nerve preoperatively must be considered in light of the expected postoperative deficit. Indeed, the feasibility of complete separation of the vascular malformation from the facial nerve is questionable given the findings of Isaacson et al. who noted that in the majority of cases (five of six), the facial nerve had to be resected for complete removal [10]. In these cases, the vascular lesions were found to be infiltrating the nerve. Thus
Table 1 Comparison of clinical and diagnostic features of GGVM and cholesteatoma [1–5,9].
GGVM
Audiogram physical exam
Location
CT
MRI
Conductive hearing loss Facial paralysis, unilateral hearing loss
Centered upon the geniculate ganglion
Intralesional calcifications and bony spicules, irregular borders
T2-weighted hyperintense, T1-weighted post-gadolinium enhancement
Anterosuperior Conductive hearing loss T2-weighted hyperintense, T1-weighted Smooth, marginated bony erosion mesotympanum mass Facial paralysis unilateral hypointense; no post-gadolinium enhancement hearing loss CT, computed tomography; GGVM, geniculate ganglion venous malformation; and MRI, magnetic resonance imaging. Cholesteatoma
1216
J.A. Ames et al. / International Journal of Pediatric Otorhinolaryngology 76 (2012) 1214–1216
Fig. 1. Congenital cholesteatoma (A and B) and GGVM (C and D). Axial computed tomography scan (A and B) shows a soft tissue opacification in the anterosuperior quadrant of the tympanum with characteristic smoothly marginated erosion of the surrounding bone with interruption of the ossicles, consistent with a congenital cholesteatoma. In contrast, computed tomographic imaging suggestive of GGVM includes a lesion centered upon the geniculate ganglion that produces an area of irregular bony erosion with a characteristic ‘‘moth-eaten’’ appearance and intralesional calcifications (C). Magnetic resonance imaging of our patient (D) shows enhancement with gadolinium on T1weighted images, typical of GGVM. GGVM, geniculate ganglion vascular malformation.
Isaacson et al. recommend that surgical excision be deferred until the facial nerve function has declined to HB III/VI or worse. Semaan et al. found that the electromyographic findings in patients with this GGVM showed a mixed pattern of degeneration and regeneration, with simultaneous presence of fibrillation potentials and polyphasic action potentials [4]. In the series by Semaan et al., although six of 18 patients had excision of the lesion without nerve sacrifice, the patients who did require a nerve graft had worse postoperative facial nerve function. Therefore, early resection of the lesion to prevent irreversible nerve degeneration may not be warranted. The traditional management of venous malformations of the head and neck includes observation, sclerotherapy, surgical resection, and laser treatments. Unlike the treatment strategy for hemangiomas, which have characteristic periods of growth, then involution, venous malformations are managed with the expectation that they will grow in proportion with the patient. The frequently multi-septated, complex structure of head and neck venous malformations often results in excessive blood loss and potential neurologic sequelae during surgery, which is why observation, sclerotherapy, and laser treatment are more commonly used. Injection sclerotherapy poses a risky option in which sclerosants could cause significant ototoxicity or endarterial labyrinthine damage. Intra-lesional steroid injection is a viable treatment option for carefully selected hemangiomas of the face, orbit, and airway, but is likely of low efficacy in venous malformations given the low proliferative state. The prospect of intratympanic steroids, while labyrinthine-sparing, is likewise of seemingly low therapeutic benefit. Lastly, the use of a carbon dioxide or YAG laser (time-tested in otologic surgery) could be contemplated for treating the portion of the malformation surrounding the ossicles to relieve the compressive effect. Attempts to laser the component adjacent to or involving the geniculate ganglion would result in direct damage to the facial nerve. In the case presented, surgical excision is a probable eventuality given the propensity for these GGVMs to slowly enlarge and destroy facial nerve function and worsen hearing.
5. Conclusion Geniculate ganglion venous malformations are rare lesions arising within the temporal bone. In the adult literature, the primary clinical finding of a GGVM is progressive facial nerve weakness; however, our patient presented with CHL. Therefore, when evaluating a patient with a temporal bone lesion involving the GG, it is important to be vigilant for the possibility of a GGVM presenting with conductive hearing loss but without any facial nerve weakness. Careful evaluation of the imaging, including CT and MRI, will assist in distinguishing a GGVM from other temporal bone lesions, which is vital for correct preoperative diagnosis and proper medical or surgical management. Conflicts of interest The authors have no funding or conflicts of interest to disclose. References [1] C.A. Mangham, J.N. Carberry, D.E. Brackmann, Management of intratemporal vascular tumors, Laryngoscope 91 (1981) 867–876. [2] M.M. Benoit, P.E. North, M.J. McKenna, M.C. Mihm, M.M. Johnson, M.J. Cunningham, Facial nerve hemangiomas: vascular tumors or malformations? Otolaryngol. Head Neck Surg. 142 (2010) 108–114. [3] H.A. Arts, Geniculate hemangioma, in: R.K. Jackler, C.L.W. Driscoll (Eds.), Tumors of the Ear and Temporal Bone, Lippincot, Williams & Wilkins, Philadelphia, 2000, pp. 290–302. [4] M.T. Semaan, W.H. Slattery, D.E. Brackmann, Geniculate ganglion hemangiomas: clinical results and long-term follow-up, Otol. Neurotol. 31 (2010) 665–670. [5] E. Piccirillo, M. Agarwal, M.S. Rohit, T. Khrais, M. Sanna, Management of temporal bone hemangiomas, Ann. Otol. Rhinol. Laryngol. 113 (2004) 431–437. [6] H. El-Khouly, J. Fernandez-Miranda, A.L. Rhoton Jr., Blood supply of the facial nerve in the middle fossa: the petrosal artery, Neurosurgery 62 (2008) ONS297– ONS303 (discussion ONS303–ONS304). [7] O. Fierek, R. Laskawi, E. Kunze, Large intraossesous hemangioma of the temporal bone in a child, Ann. Otol. Rhinol. Laryngol. 113 (2004) 394–398. [8] E. Kley, Das intraossare angiom des schlafenbeines, eine seltene erkrankung,(Intraosseous angioma of the temporal bone—a rare disease), Z. Laryngol. Rhinol. Otol. 51 (1972) 824–829. [9] V. Achilli, S. Mignosi, Facial nerve hemangioma, Otol. Neurotol. 23 (2002) 1003–1004. [10] B. Isaacson, S.A. Telian, P.E. McKeever, H.A. Arts, Hemangiomas of the geniculate ganglion, Otol. Neurotol. 26 (2005) 796–802.