- Email: [email protected]
Trigeminal Neuralgia Due to Petrosal Bone Deformity
Case Report
Trigeminal Neuralgia Due to Petrosal Bone Deformity Sachiko Hirata1, Masahito Kobayashi1, Dai Kamamoto2, Kenzo Kosugi2, Kazunari Yoshida2, Takamitsu Fujimaki1
Key words Anterior transpetrosal approach - Microvascular decompression - Neurovascular compression - Petrous bone - Trigeminal neuralgia -
Abbreviations and Acronyms ATPA: Anterior transpetrosal approach SCA: Superior cerebellar artery From the 1Department of Neurosurgery, Saitama Medical University Hospital, Saitama; and 2Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan To whom correspondence should be addressed: Sachiko Hirata, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2019) 126:79-82. https://doi.org/10.1016/j.wneu.2019.02.114 Journal homepage: www.journals.elsevier.com/worldneurosurgery
- BACKGROUND:
There have been a few previous reports of trigeminal neuralgia caused by bony structures. We report a rare case of trigeminal neuralgia caused by petrous bone deformity.
- CASE
DESCRIPTION: A-43-year-old man with facial pain in the left maxillary and mandibular divisions of the trigeminal nerve was referred to our hospital. Computed tomography showed bone hyperplasia protruding into the left cerebellopontine cistern, compressing the left trigeminal nerve. Administration of carbamazepine ameliorated facial pain, but the effect was unsatisfactory, and microvascular decompression was performed through the anterior transpetrosal approach. The protruding petrous bone was drilled out to release compression of the trigeminal nerve, thus straightening the deviated trajectory of the nerve. The superior cerebellar artery adjacent to the thickened petrosal bone seemed to have compressed the trigeminal nerve and was also transposed. The facial pain disappeared completely after microvascular decompression surgery.
- CONCLUSIONS:
The anterior transpetrosal approach is an appropriate and essential strategy for trigeminal neuralgia caused by petrous bone deformity of the petrous apex.
Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Published by Elsevier Inc.
INTRODUCTION Trigeminal neuralgia is generally caused by vascular compression,1 although other lesions, such as tumors, may also provoke this condition by compressing the trigeminal nerve directly or by causing indirect compression by the cerebellar arteries.2-12 There have been a few previous reports of trigeminal neuralgia caused by bony structures, representing disease with no or slow progression.13,14 We present a case of trigeminal neuralgia caused by petrous bone deformity in which the symptoms improved after surgery performed via the anterior transpetrosal approach (ATPA).
CASE DESCRIPTION History A 43-year-old man presented to our hospital with worsening facial pain in the left maxillary (V2) and mandibular (V3) divisions of the trigeminal nerve, which began 2 years previously. The patient reported shooting and stunning facial pain of
very short duration triggered by mastication and sensory input on the left nasal alar. A diagnosis of trigeminal neuralgia was made, and carbamazepine was administered for 8 months. This treatment ameliorated his symptoms, but the effect was not satisfactory, and he was admitted to our hospital for surgical intervention. He had no relevant perinatal history and had normal development. In addition, he had no history of malignant diseases, severe head injury, or any relevant familial history.
Examination Head computed tomography showed asymmetry of the cerebellopontine cistern due to thickening of the left petrous bone, which protruded medially (Figure 1A). Brain magnetic resonance imaging showed compression and marked transformation of the trigeminal nerve by the thickened petrous bone (Figure 1B). Magnetic resonance angiography and constructive interference in steady state imaging showed the superior cerebellar artery (SCA) to be located in the narrowed cistern between the deformed petrous bone and brainstem, adjacent to the left
WORLD NEUROSURGERY 126: 79-82, JUNE 2019
trigeminal nerve, and therefore it could be involved in compression of the trigeminal nerve (Figure 1C and D). Considering the distance from the skull surface to the petrous apex, an operative view including the whole length of the trigeminal nerve and secure resection of petrous bone, microvascular decompression surgery was planned with a left ATPA. The surgery was performed by 1 of the authors (K.Y.).
Operation and Pathologic Findings The patient was placed in the supine lateral position. His head side was elevated to 20 by tilting the operating table, and his left shoulder was elevated to 20 with his head rotated toward the right side to the complete lateral position. After temporal craniotomy and an additional temporal osteotomy toward the middle cranial fossa, the left temporal lobe covered with the dura mater was elevated extradurally to expose the left petrous bone, preserving the greater superficial petrosal nerve. The abnormally thickened bone, including the posteromedial triangle of the petrous apex, was drilled out. After resection of the dura mater of the middle fossa and posterior
www.journals.elsevier.com/world-neurosurgery
79
CASE REPORT SACHIKO HIRATA ET AL.
TRIGEMINAL NEURALGIA DUE TO PETROUS BONE
Figure 1. (A) Preoperative computed tomography showing a thickened left petrous bone protruding medially and narrowed left cerebellopontine cistern. (B) T2-weighted magnetic resonance imaging revealing marked compression of the left trigeminal nerve by the thickened petrous bone (arrow). (C) Magnetic resonance angiography showing the superior
fossa, the superior petrosal sinus was transected after coagulation, and the tentorium cerebelli was resected. The left trigeminal nerve was found to be compressed by the protruding bony deformity with deviation of its course owing to thick fibrous tissue and dura mater around Meckel cave (Figure 2A). The SCA, located rostral to the
80
www.SCIENCEDIRECT.com
cerebellar artery (arrow) located in the narrowed cistern adjacent to the trigeminal nerve. (D) Coronal constructive interference in steady state imaging indicating the superior cerebellar artery (arrowhead) and trigeminal nerve (arrow) were located in the narrowed cistern because of the thickened left petrous bone (asterisk).
trigeminal nerve, was also in contact with the nerve at the site opposite the protruding bone (Figure 2B). The left trigeminal nerve was released by resection of the dura mater of Meckel cave and most of the surrounding fibrous tissue. The trigeminal nerve was freed from compression by the deformed bony structure
and dura mater, and finally the deviated trajectory of the nerve was straightened. The SCA was transposed away from the trigeminal nerve and was adhered to the dura mater with fibrin glue and small pieces of collagen sponge. Postoperative three-dimensional computed tomography images showed the area of bone removal (Figure 3).
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2019.02.114
CASE REPORT SACHIKO HIRATA ET AL.
TRIGEMINAL NEURALGIA DUE TO PETROUS BONE
Figure 2. Operative views. (A) The thickened left petrous bone was drilled out, and the thick fibrous tissue and dura mater around Meckel cave were resected. The left trigeminal nerve (asterisk) was exposed, which was compressed by the protruding bone at the entrance of Meckel cave (arrow). An impression was observed on the deviated trigeminal nerve (arrowhead). (B) The trigeminal nerve (asterisk) was also compressed by the superior cerebellar artery (white arrowhead) at the medial rostral side opposite the protruding bone compression (arrow).
Postoperative Course The patient experienced relief of intractable facial pain immediately after the operation. However, he also demonstrated slight hypoesthesia of the left side of the face and transient slight trochlear nerve paresis, both of which recovered spontaneously without any specific treatment within 6 months. There were no other surgical complications, such as cerebrospinal fluid leakage or wound infection. DISCUSSION Trigeminal neuralgia occurs at a rate of approximately 4 or 5 per 100,000 in the
general population. The trigeminal root is most commonly compressed by the superior cerebellar artery (75%) and vein (68%) in patients with trigeminal neuralgia.1 The suboccipital approach is useful and is most commonly applied for microvascular decompression surgery in cases of trigeminal neuralgia.4 In addition to vascular compression, trigeminal neuralgia can be caused by other lesions, such as tumors (meningioma, schwannoma, epidermoid cyst, metastatic tumors, and lipoma), aneurysms, cavernous hemangioma, anterior venous malformation, and arachnoid cysts.2,3,5-12 The mechanism underlying tumor-induced
WORLD NEUROSURGERY 126: 79-82, JUNE 2019
trigeminal neuralgia involves mechanical and chemical stimulation of the nerve.9 Besides tumors, bony structures, including narrowed cerebellopontine cistern, and length of the trigeminal nerve have been shown to promote the pathogenesis of trigeminal neuralgia.15-20 However, there have been only a few reports of trigeminal neuralgia mainly caused by bony structures, such as Paget disease,15 basilar impression,13 and endostosis of the petrous bone.14 The first was a case report describing bilateral trigeminal neuralgia with Paget disease, and decompression surgery for the margins of the trigeminal foramen was performed through a left temporal extradural approach with the patient in the sitting position.15 The second report suggested that craniovertebral junction malformations may cause neuralgia by compression of the trigeminal nucleus or the nerve root entry zone.13 The third report was a case report in Spanish describing trigeminal neuralgia due to endostosis of the petrous bone and arterial vascular compression.14 The endostosis was a localized protrusion of a bony tubercle of the suprameatal area, which could be removed with decompression of the compressing artery via the standard unilateral suboccipital approach. Shenouda and Coakham21 reported petrous endostosis in 15 (3.4%) of 440 patients with trigeminal neuralgia. In their series, the endostosis obscured the site of trigeminal compression but did not compress the trigeminal nerves directly. Most of the neurovascular conflicts were pontotrigeminal veins, and good surgical outcomes were achieved by the suboccipital approach with endoscopy or drilling the endostosis.21 The present report is therefore the first documentation of trigeminal neuralgia caused by petrous bone deformity requiring resection of the petrous apex area and treated successfully by skull base surgery via the ATPA. Direct compression by the bony structure is the most likely mechanism underlying trigeminal neuralgia caused by petrous bone deformity. As the symptoms in the present case developed over a period of 2 years, the petrosal bone deformity may also have induced secondary inflammation around the nerve. The SCA, the most common vessel involved in trigeminal neuralgia, showed no obvious compression during surgery but may have been transposed owing to decompression of the petrous bone and resection of
www.journals.elsevier.com/world-neurosurgery
81
CASE REPORT SACHIKO HIRATA ET AL.
TRIGEMINAL NEURALGIA DUE TO PETROUS BONE
12. Tancioni F, Gaetani P, Villani L, Zappoli F, Rodriguez Y, Baena R. Neurinoma of the trigeminal root and atypical trigeminal neuralgia: case report and review of the literature. Surg Neurol. 1995;44:36-42. 13. de Almeida Holanda MM, Pereira Neto NG, de Moura Peixoto G, Pinheiro Santos RH. Trigeminal neuralgia secondary to basilar impression: a case report. J Craniovertebr Junction Spine. 2015;6:76-78.
Figure 3. Bone window computed tomography before (A) and after (B) surgery. The protruding petrous bone was resected (arrowheads).
the dura mater. The branch of the SCA adjacent to the trigeminal nerve was small, but pulsatile compression of the nerve by the cerebellar arteries may have been provoked in the narrowed posterior cranial fossa. Furthermore, our case clearly demonstrated the efficacy of the ATPA for trigeminal neuralgia with petroclival or petrous lesions. The suboccipital approach is useful and is most commonly applied for microvascular decompression surgery in cases of trigeminal neuralgia. However, this approach is not appropriate to observe and work around Meckel cave. The ATPA is a practical approach for use in cases in which it is necessary to drill the petrous bone. The anterior part of the petrous bone is resected through the extradural corridor, protecting the brain and cranial nerves as well as the petrosal veins and superior petrosal sinus,14 which can be problematic via the suboccipital approach. The whole length of the trigeminal nerve can be observed and easily manipulated with only minimal incision of the tentorium and dura mater. The ATPA is an essential technique for resection of petrous apex lesions in cases of trigeminal neuralgia, as in the case presented here, and to provide a good operative view that allows observation of the full length of the trigeminal nerve with minimal compression of the cerebellum and brainstem. CONCLUSIONS Petrous bone deformity can cause trigeminal neuralgia owing to direct compression by the bone and vessels as well as possibly compression by the thickened dura mater or secondary inflammation. The ATPA is an appropriate and safe strategy for treatment in such cases.
82
www.SCIENCEDIRECT.com
REFERENCES 1. Barker FG 2nd, Jannetta PJ, Bissonette DJ, Larkins MV, Jho HD. The long-term outcome of microvascular decompression for trigeminal neuralgia. N Engl J Med. 1996;334:1077-1083. 2. Bubu R, Murali R. Arachnoid cyst of the cerebellopontine angle manifesting as contralateral trigeminal neuralgia: case report. Neurosurgery. 1991;28:886-887. 3. Cenzato M, Stefini R, Ambrosi C, Latronico N, Milani D. Surgical resolution of trigeminal neuralgia due to intra-axial compression by pontine cavernous angioma. World Neurosurg. 2010;74:544-546. 4. Fujimaki T, Kirino T. Combined transhorizontalsupracerebellar approach for microvascular decompression of trigeminal neuralgia. Br J Neurosurg. 2000;14:531-534. 5. García-Pastor C, López-González F, Revuelta R, Nathal E. Trigeminal neuralgia secondary to arteriovenous malformations of the posterior fossa. Surg Neurol. 2006;66:207-211. 6. Haddad FS, Taha JM. An unusual cause for trigeminal neuralgia: contralateral meningioma of the posterior fossa. Neurosurgery. 1990;26:1033-1038. 7. Inatomi Y, Inoue T, Nagata S, Matsuno H, Itoh Y. Trigeminal neuralgia caused by the metastasis of malignant lymphoma to the trigeminal nerve: a case report. No Shinkei Geka. 1998;26:401-405.
14. Mata-Gómez J, Royano-Sánchez M, BejaranoParra M, Gilete-Tejero I, Rico-Cotelo M, OrtegaMartínez M. Trigeminal neuralgia secondary to petrous endostosis [in Spanish] Neurocirugia (Astur). 2017;28:247-250. 15. Gardner WJ, Dohn DF. Trigeminal neuralgia— hemifacial spasm—Paget’s disease: significance of this association. Brain. 1966;89:555-562. 16. Horínek D, Brezová V, Nimsky C, et al. The MRI volumetry of the posterior fossa and its substructures in trigeminal neuralgia: a validated study. Acta Neurochir (Wien). 2009;151:669-675. 17. Parise M, Ribeiro CT, Vincent M, Gasparetto E. Small cerebellopontine angle cisterns in patients with trigeminal neuralgia. J Neurosurg. 2010;112: 900-901 [author reply: 901]. 18. Ha SM, Kim SH, Yoo EH, et al. Patients with idiopathic trigeminal neuralgia have a sharperthan-normal trigeminal-pontine angle and trigeminal nerve atrophy. Acta Neurochir (Wien). 2012; 154:1627-1633. 19. Parise M, Acioly MA, Ribeiro CT, Vincent M, Gasparetto EL. The role of the cerebellopontine angle cistern area and trigeminal nerve length in the pathogenesis of trigeminal neuralgia: a prospective case-control study. Acta Neurochir (Wien). 2013;155:863-868. 20. Brinzeu A, Dumot C, Sindou M. Role of the petrous ridge and angulation of the trigeminal nerve in the pathogenesis of trigeminal neuralgia, with implications for microvascular decompression. Acta Neurochir (Wien). 2018;160:971-976.
8. Kato T, Sawamura Y, Abe H. Trigeminal neuralgia caused by a cerebellopontine-angle lipoma: case report. Surg Neurol. 1995;44:33-35.
21. Shenouda EF, Coakham HB. Management of petrous endostosis in posterior fossa procedures for trigeminal neuralgia. Neurosurgery. 2007;60(2 suppl 1):ONS63-ONS69 [discussion: ONS69].
9. Kobata H, Kondo A, Iwasaki K. Cerebellopontine angle epidermoids presenting with cranial nerve hyperactive dysfunction: pathogenesis and longterm surgical results in 30 patients. Neurosurgery. 2002;50:276-285.
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 23 December 2018; accepted 19 February 2019
10. Majoie CB, Hulsmans FJ, Castelijns JA, Verbeeten B Jr, Tiren D, van Beek EJ. Symptoms and signs related to the trigeminal nerve: diagnostic yield of MR imaging. Radiology. 1998;209:557-562. 11. Ogleznev KYa, Grigoryan YuA, Slavin KV. Parapontine epidermoid tumours presenting as trigeminal neuralgias: anatomical findings and operative results. Acta Neurochir. 1991;110:116-119.
Citation: World Neurosurg. (2019) 126:79-82. https://doi.org/10.1016/j.wneu.2019.02.114 Journal homepage: www.journals.elsevier.com/worldneurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Published by Elsevier Inc.
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2019.02.114
Trigeminal Neuralgia Due to Petrosal Bone Deformity Sachiko Hirata1, Masahito Kobayashi1, Dai Kamamoto2, Kenzo Kosugi2, Kazunari Yoshida2, Takamitsu Fujimaki1
Key words Anterior transpetrosal approach - Microvascular decompression - Neurovascular compression - Petrous bone - Trigeminal neuralgia -
Abbreviations and Acronyms ATPA: Anterior transpetrosal approach SCA: Superior cerebellar artery From the 1Department of Neurosurgery, Saitama Medical University Hospital, Saitama; and 2Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan To whom correspondence should be addressed: Sachiko Hirata, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2019) 126:79-82. https://doi.org/10.1016/j.wneu.2019.02.114 Journal homepage: www.journals.elsevier.com/worldneurosurgery
- BACKGROUND:
There have been a few previous reports of trigeminal neuralgia caused by bony structures. We report a rare case of trigeminal neuralgia caused by petrous bone deformity.
- CASE
DESCRIPTION: A-43-year-old man with facial pain in the left maxillary and mandibular divisions of the trigeminal nerve was referred to our hospital. Computed tomography showed bone hyperplasia protruding into the left cerebellopontine cistern, compressing the left trigeminal nerve. Administration of carbamazepine ameliorated facial pain, but the effect was unsatisfactory, and microvascular decompression was performed through the anterior transpetrosal approach. The protruding petrous bone was drilled out to release compression of the trigeminal nerve, thus straightening the deviated trajectory of the nerve. The superior cerebellar artery adjacent to the thickened petrosal bone seemed to have compressed the trigeminal nerve and was also transposed. The facial pain disappeared completely after microvascular decompression surgery.
- CONCLUSIONS:
The anterior transpetrosal approach is an appropriate and essential strategy for trigeminal neuralgia caused by petrous bone deformity of the petrous apex.
Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Published by Elsevier Inc.
INTRODUCTION Trigeminal neuralgia is generally caused by vascular compression,1 although other lesions, such as tumors, may also provoke this condition by compressing the trigeminal nerve directly or by causing indirect compression by the cerebellar arteries.2-12 There have been a few previous reports of trigeminal neuralgia caused by bony structures, representing disease with no or slow progression.13,14 We present a case of trigeminal neuralgia caused by petrous bone deformity in which the symptoms improved after surgery performed via the anterior transpetrosal approach (ATPA).
CASE DESCRIPTION History A 43-year-old man presented to our hospital with worsening facial pain in the left maxillary (V2) and mandibular (V3) divisions of the trigeminal nerve, which began 2 years previously. The patient reported shooting and stunning facial pain of
very short duration triggered by mastication and sensory input on the left nasal alar. A diagnosis of trigeminal neuralgia was made, and carbamazepine was administered for 8 months. This treatment ameliorated his symptoms, but the effect was not satisfactory, and he was admitted to our hospital for surgical intervention. He had no relevant perinatal history and had normal development. In addition, he had no history of malignant diseases, severe head injury, or any relevant familial history.
Examination Head computed tomography showed asymmetry of the cerebellopontine cistern due to thickening of the left petrous bone, which protruded medially (Figure 1A). Brain magnetic resonance imaging showed compression and marked transformation of the trigeminal nerve by the thickened petrous bone (Figure 1B). Magnetic resonance angiography and constructive interference in steady state imaging showed the superior cerebellar artery (SCA) to be located in the narrowed cistern between the deformed petrous bone and brainstem, adjacent to the left
WORLD NEUROSURGERY 126: 79-82, JUNE 2019
trigeminal nerve, and therefore it could be involved in compression of the trigeminal nerve (Figure 1C and D). Considering the distance from the skull surface to the petrous apex, an operative view including the whole length of the trigeminal nerve and secure resection of petrous bone, microvascular decompression surgery was planned with a left ATPA. The surgery was performed by 1 of the authors (K.Y.).
Operation and Pathologic Findings The patient was placed in the supine lateral position. His head side was elevated to 20 by tilting the operating table, and his left shoulder was elevated to 20 with his head rotated toward the right side to the complete lateral position. After temporal craniotomy and an additional temporal osteotomy toward the middle cranial fossa, the left temporal lobe covered with the dura mater was elevated extradurally to expose the left petrous bone, preserving the greater superficial petrosal nerve. The abnormally thickened bone, including the posteromedial triangle of the petrous apex, was drilled out. After resection of the dura mater of the middle fossa and posterior
www.journals.elsevier.com/world-neurosurgery
79
CASE REPORT SACHIKO HIRATA ET AL.
TRIGEMINAL NEURALGIA DUE TO PETROUS BONE
Figure 1. (A) Preoperative computed tomography showing a thickened left petrous bone protruding medially and narrowed left cerebellopontine cistern. (B) T2-weighted magnetic resonance imaging revealing marked compression of the left trigeminal nerve by the thickened petrous bone (arrow). (C) Magnetic resonance angiography showing the superior
fossa, the superior petrosal sinus was transected after coagulation, and the tentorium cerebelli was resected. The left trigeminal nerve was found to be compressed by the protruding bony deformity with deviation of its course owing to thick fibrous tissue and dura mater around Meckel cave (Figure 2A). The SCA, located rostral to the
80
www.SCIENCEDIRECT.com
cerebellar artery (arrow) located in the narrowed cistern adjacent to the trigeminal nerve. (D) Coronal constructive interference in steady state imaging indicating the superior cerebellar artery (arrowhead) and trigeminal nerve (arrow) were located in the narrowed cistern because of the thickened left petrous bone (asterisk).
trigeminal nerve, was also in contact with the nerve at the site opposite the protruding bone (Figure 2B). The left trigeminal nerve was released by resection of the dura mater of Meckel cave and most of the surrounding fibrous tissue. The trigeminal nerve was freed from compression by the deformed bony structure
and dura mater, and finally the deviated trajectory of the nerve was straightened. The SCA was transposed away from the trigeminal nerve and was adhered to the dura mater with fibrin glue and small pieces of collagen sponge. Postoperative three-dimensional computed tomography images showed the area of bone removal (Figure 3).
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2019.02.114
CASE REPORT SACHIKO HIRATA ET AL.
TRIGEMINAL NEURALGIA DUE TO PETROUS BONE
Figure 2. Operative views. (A) The thickened left petrous bone was drilled out, and the thick fibrous tissue and dura mater around Meckel cave were resected. The left trigeminal nerve (asterisk) was exposed, which was compressed by the protruding bone at the entrance of Meckel cave (arrow). An impression was observed on the deviated trigeminal nerve (arrowhead). (B) The trigeminal nerve (asterisk) was also compressed by the superior cerebellar artery (white arrowhead) at the medial rostral side opposite the protruding bone compression (arrow).
Postoperative Course The patient experienced relief of intractable facial pain immediately after the operation. However, he also demonstrated slight hypoesthesia of the left side of the face and transient slight trochlear nerve paresis, both of which recovered spontaneously without any specific treatment within 6 months. There were no other surgical complications, such as cerebrospinal fluid leakage or wound infection. DISCUSSION Trigeminal neuralgia occurs at a rate of approximately 4 or 5 per 100,000 in the
general population. The trigeminal root is most commonly compressed by the superior cerebellar artery (75%) and vein (68%) in patients with trigeminal neuralgia.1 The suboccipital approach is useful and is most commonly applied for microvascular decompression surgery in cases of trigeminal neuralgia.4 In addition to vascular compression, trigeminal neuralgia can be caused by other lesions, such as tumors (meningioma, schwannoma, epidermoid cyst, metastatic tumors, and lipoma), aneurysms, cavernous hemangioma, anterior venous malformation, and arachnoid cysts.2,3,5-12 The mechanism underlying tumor-induced
WORLD NEUROSURGERY 126: 79-82, JUNE 2019
trigeminal neuralgia involves mechanical and chemical stimulation of the nerve.9 Besides tumors, bony structures, including narrowed cerebellopontine cistern, and length of the trigeminal nerve have been shown to promote the pathogenesis of trigeminal neuralgia.15-20 However, there have been only a few reports of trigeminal neuralgia mainly caused by bony structures, such as Paget disease,15 basilar impression,13 and endostosis of the petrous bone.14 The first was a case report describing bilateral trigeminal neuralgia with Paget disease, and decompression surgery for the margins of the trigeminal foramen was performed through a left temporal extradural approach with the patient in the sitting position.15 The second report suggested that craniovertebral junction malformations may cause neuralgia by compression of the trigeminal nucleus or the nerve root entry zone.13 The third report was a case report in Spanish describing trigeminal neuralgia due to endostosis of the petrous bone and arterial vascular compression.14 The endostosis was a localized protrusion of a bony tubercle of the suprameatal area, which could be removed with decompression of the compressing artery via the standard unilateral suboccipital approach. Shenouda and Coakham21 reported petrous endostosis in 15 (3.4%) of 440 patients with trigeminal neuralgia. In their series, the endostosis obscured the site of trigeminal compression but did not compress the trigeminal nerves directly. Most of the neurovascular conflicts were pontotrigeminal veins, and good surgical outcomes were achieved by the suboccipital approach with endoscopy or drilling the endostosis.21 The present report is therefore the first documentation of trigeminal neuralgia caused by petrous bone deformity requiring resection of the petrous apex area and treated successfully by skull base surgery via the ATPA. Direct compression by the bony structure is the most likely mechanism underlying trigeminal neuralgia caused by petrous bone deformity. As the symptoms in the present case developed over a period of 2 years, the petrosal bone deformity may also have induced secondary inflammation around the nerve. The SCA, the most common vessel involved in trigeminal neuralgia, showed no obvious compression during surgery but may have been transposed owing to decompression of the petrous bone and resection of
www.journals.elsevier.com/world-neurosurgery
81
CASE REPORT SACHIKO HIRATA ET AL.
TRIGEMINAL NEURALGIA DUE TO PETROUS BONE
12. Tancioni F, Gaetani P, Villani L, Zappoli F, Rodriguez Y, Baena R. Neurinoma of the trigeminal root and atypical trigeminal neuralgia: case report and review of the literature. Surg Neurol. 1995;44:36-42. 13. de Almeida Holanda MM, Pereira Neto NG, de Moura Peixoto G, Pinheiro Santos RH. Trigeminal neuralgia secondary to basilar impression: a case report. J Craniovertebr Junction Spine. 2015;6:76-78.
Figure 3. Bone window computed tomography before (A) and after (B) surgery. The protruding petrous bone was resected (arrowheads).
the dura mater. The branch of the SCA adjacent to the trigeminal nerve was small, but pulsatile compression of the nerve by the cerebellar arteries may have been provoked in the narrowed posterior cranial fossa. Furthermore, our case clearly demonstrated the efficacy of the ATPA for trigeminal neuralgia with petroclival or petrous lesions. The suboccipital approach is useful and is most commonly applied for microvascular decompression surgery in cases of trigeminal neuralgia. However, this approach is not appropriate to observe and work around Meckel cave. The ATPA is a practical approach for use in cases in which it is necessary to drill the petrous bone. The anterior part of the petrous bone is resected through the extradural corridor, protecting the brain and cranial nerves as well as the petrosal veins and superior petrosal sinus,14 which can be problematic via the suboccipital approach. The whole length of the trigeminal nerve can be observed and easily manipulated with only minimal incision of the tentorium and dura mater. The ATPA is an essential technique for resection of petrous apex lesions in cases of trigeminal neuralgia, as in the case presented here, and to provide a good operative view that allows observation of the full length of the trigeminal nerve with minimal compression of the cerebellum and brainstem. CONCLUSIONS Petrous bone deformity can cause trigeminal neuralgia owing to direct compression by the bone and vessels as well as possibly compression by the thickened dura mater or secondary inflammation. The ATPA is an appropriate and safe strategy for treatment in such cases.
82
www.SCIENCEDIRECT.com
REFERENCES 1. Barker FG 2nd, Jannetta PJ, Bissonette DJ, Larkins MV, Jho HD. The long-term outcome of microvascular decompression for trigeminal neuralgia. N Engl J Med. 1996;334:1077-1083. 2. Bubu R, Murali R. Arachnoid cyst of the cerebellopontine angle manifesting as contralateral trigeminal neuralgia: case report. Neurosurgery. 1991;28:886-887. 3. Cenzato M, Stefini R, Ambrosi C, Latronico N, Milani D. Surgical resolution of trigeminal neuralgia due to intra-axial compression by pontine cavernous angioma. World Neurosurg. 2010;74:544-546. 4. Fujimaki T, Kirino T. Combined transhorizontalsupracerebellar approach for microvascular decompression of trigeminal neuralgia. Br J Neurosurg. 2000;14:531-534. 5. García-Pastor C, López-González F, Revuelta R, Nathal E. Trigeminal neuralgia secondary to arteriovenous malformations of the posterior fossa. Surg Neurol. 2006;66:207-211. 6. Haddad FS, Taha JM. An unusual cause for trigeminal neuralgia: contralateral meningioma of the posterior fossa. Neurosurgery. 1990;26:1033-1038. 7. Inatomi Y, Inoue T, Nagata S, Matsuno H, Itoh Y. Trigeminal neuralgia caused by the metastasis of malignant lymphoma to the trigeminal nerve: a case report. No Shinkei Geka. 1998;26:401-405.
14. Mata-Gómez J, Royano-Sánchez M, BejaranoParra M, Gilete-Tejero I, Rico-Cotelo M, OrtegaMartínez M. Trigeminal neuralgia secondary to petrous endostosis [in Spanish] Neurocirugia (Astur). 2017;28:247-250. 15. Gardner WJ, Dohn DF. Trigeminal neuralgia— hemifacial spasm—Paget’s disease: significance of this association. Brain. 1966;89:555-562. 16. Horínek D, Brezová V, Nimsky C, et al. The MRI volumetry of the posterior fossa and its substructures in trigeminal neuralgia: a validated study. Acta Neurochir (Wien). 2009;151:669-675. 17. Parise M, Ribeiro CT, Vincent M, Gasparetto E. Small cerebellopontine angle cisterns in patients with trigeminal neuralgia. J Neurosurg. 2010;112: 900-901 [author reply: 901]. 18. Ha SM, Kim SH, Yoo EH, et al. Patients with idiopathic trigeminal neuralgia have a sharperthan-normal trigeminal-pontine angle and trigeminal nerve atrophy. Acta Neurochir (Wien). 2012; 154:1627-1633. 19. Parise M, Acioly MA, Ribeiro CT, Vincent M, Gasparetto EL. The role of the cerebellopontine angle cistern area and trigeminal nerve length in the pathogenesis of trigeminal neuralgia: a prospective case-control study. Acta Neurochir (Wien). 2013;155:863-868. 20. Brinzeu A, Dumot C, Sindou M. Role of the petrous ridge and angulation of the trigeminal nerve in the pathogenesis of trigeminal neuralgia, with implications for microvascular decompression. Acta Neurochir (Wien). 2018;160:971-976.
8. Kato T, Sawamura Y, Abe H. Trigeminal neuralgia caused by a cerebellopontine-angle lipoma: case report. Surg Neurol. 1995;44:33-35.
21. Shenouda EF, Coakham HB. Management of petrous endostosis in posterior fossa procedures for trigeminal neuralgia. Neurosurgery. 2007;60(2 suppl 1):ONS63-ONS69 [discussion: ONS69].
9. Kobata H, Kondo A, Iwasaki K. Cerebellopontine angle epidermoids presenting with cranial nerve hyperactive dysfunction: pathogenesis and longterm surgical results in 30 patients. Neurosurgery. 2002;50:276-285.
Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 23 December 2018; accepted 19 February 2019
10. Majoie CB, Hulsmans FJ, Castelijns JA, Verbeeten B Jr, Tiren D, van Beek EJ. Symptoms and signs related to the trigeminal nerve: diagnostic yield of MR imaging. Radiology. 1998;209:557-562. 11. Ogleznev KYa, Grigoryan YuA, Slavin KV. Parapontine epidermoid tumours presenting as trigeminal neuralgias: anatomical findings and operative results. Acta Neurochir. 1991;110:116-119.
Citation: World Neurosurg. (2019) 126:79-82. https://doi.org/10.1016/j.wneu.2019.02.114 Journal homepage: www.journals.elsevier.com/worldneurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Published by Elsevier Inc.
WORLD NEUROSURGERY, https://doi.org/10.1016/j.wneu.2019.02.114