The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
2. Keller EE. Reconstruction of the severely atrophic edentulous mandible with endosseous implants: a 10-year longitudinal study. J Oral Maxillofac Surg 1995;53:305Y320 3. Papay FA, Zins JE, Hahn JF. Split calvarial bone graft in cranio-orbital sphenoid wing reconstruction. J Craniofac Surg 1996;7:133Y139 4. Donovan MG, Dickerson NC, Hellstein JW, et al. Autologous calvarial and iliac onlay bone grafts in miniature swine. J Oral Maxillofac Surg 1993;51:898Y903 5. Smolka W, Eggensperger N, Carollo V, et al. Changes in the volume and density of calvarial split bone grafts after alveolar ridge augmentation. Clin Oral Implants Res 2006;17:149Y155 6. Vermeeren JI, Wismeijer D, van Waas MA. One-step reconstruction of the severely resorbed mandible with onlay bone grafts and endosteal implants. A 5-year follow-up. Int J Oral Maxillofac Surg 1996;25:112Y115 7. Adell R, Lekholm U, Gro¨ndahl K, et al. Reconstruction of severely resorbed edentulous maxillae using osseointegrated fixtures in immediate autogenous bone grafts. Int J Oral Maxillofac Implants 1990;5:233Y246 8. Nystro¨m E, Legrell PE, Forssell A, et al. Combined use of bone grafts and implants in the severely resorbed maxilla. Postoperative evaluation by computed tomography. Int J Oral Maxillofac Surg 1995;24:20Y25 9. Esposito M, Hirsch JM, Lekholm U, et al. Biological factors contributing to failures of osseointegrated oral implants. (II). Etiopathogenesis. Eur J Oral Sci 1998;106:721Y764 10. Raghoebar GM, Batenburg RH, Timmenga NM, et al. Morbidity and complications of bone grafting of the floor of the maxillary sinus for the placement of endosseous implants. Mund Kiefer Gesichtschir 1999;3:S65YS69 11. Esposito M, Cannizarro G, Soardi E, et al. A 3-year post-loading report of a randomised controlled trial on the rehabilitation of posterior atrophic mandibles: short implants or longer implants in vertically augmented bone? Eur J Oral Implantol 2011;4:301Y311 12. Esposito M, Cannizzaro G, Soardi E, et al. Posterior atrophic jaws rehabilitated with prostheses supported by 6 mm-long, 4 mm-wide implants or by longer implants in augmented bone. Preliminary results from a pilot randomised controlled trial. Eur J Oral Implantol 2012;5:19Y33 13. Keller EE, Tolman DE. Mandibular ridge augmentation with simultaneous onlay iliac bone graft and endosseous implants: a preliminary report. Int J Oral Maxillofac Implants 1992;7:176Y184 14. Neukam FW, Scheller H, Gu¨nay H. Osteo-integrated 2-phase Bra˚nemark implants. Experiments with the therapeutic concept to restore the chewing function in atrophic jaws. Niedersachs Zahnarztebl 1987;22:441Y445 15. Cuesta Gil M, Bucci T, Duarte Ruiz B, et al. Reconstruction of the severely atrophic mandible using autologous calvarial bone graft: an ‘‘inverted sandwich’’ graft technique and dental rehabilitation with fixed implant-supported prostheses. J Craniomaxillofac Surg 2010;38:379Y384 16. Gutta R, Waite PD. Cranial bone grafting and simultaneous implants: a submental technique to reconstruct the atrophic mandible. Br J Oral Maxillofac Surg 2008;46:477Y479 17. Verhoeven JW, Cune MS, Terlou M, et al. The combined use of endosteal implants and iliac crest onlay grafts in the severely atrophic mandible: a longitudinal study. Int J Oral Maxillofac Surg 1997;26:351Y357 18. Chen NT, Glowacki J, Bucky LP, et al. The roles of revascularization and resorption on endurance of craniofacial onlay bone grafts in the rabbit. Plast Reconstr Surg 1994;93:714Y722; discussion 723Y724 19. Iizuka T, Smolka W, Hallermann W, et al. Extensive augmentation of the alveolar ridge using autogenous calvarial split bone grafts for dental rehabilitation. Clin Oral Implants Res 2004;15:607Y615 20. Iturriaga MT, Ruiz CC. Maxillary sinus reconstruction with calvarium bone grafts and endosseous implants. J Oral Maxillofac Surg 2004;62:344Y347
Brief Clinical Studies
Recurring Craniofacial Fibrous Dysplasia With Extensive Titanium Mesh Invasion Honggang Wu, MD, Jin Li, MD, Jianguo Xu, MD, Chao You, MD, Siqing Huang, MD Abstract: The recurrence and regrowth of craniofacial fibrous dysplasia (FD) along the repaired titanium mesh (TM) after total removal are extremely rare. A 22-year-old man was admitted to our hospital complaining of progressive proptosis and sudden vision loss of the right eye. Craniofacial FD was histologically diagnosed 3 years ago, and the involved frontal bone was totally removed and reconstructed with TM in his first surgery. Based on previous medical history, radiographic features, and clinical findings, the recurrence was considered, and the patient underwent surgical treatment. He had an uneventful postoperative course, and during the follow-up, his proptosis was gradually relieved, and the visual acuity also improved. In this article, we present the regrowth of craniofacial FD into TM and describe the clinical features, mechanism, and treatment of this condition. Key Words: Fibrous dysplasia, craniofacial fibrous dysplasia, titanium mesh reconstruction, recurrence, invasion
F
ibrous dysplasia (FD) is a kind of benign, slowly progressive bone lesion with the replacement of normal bone tissues by gradual abnormal proliferation of fibrous tissue, which accounts for about 2.5% of all primary bone masses and 7% of benign bone masses. These lesions may involve a single (monostotic) or multiple bones (polyostotic). Most FDs begin at around 10 years of age and stop progressing after puberty; however, evidence showing lasting growth after adolescence is reported as well.8,10Y12 Craniofacial FD represents 10% to 27% of patients with monostotic FD.13 It may involve all parts of the skull. The most common sites include the frontal, orbital, and ethmoid bones. Maxilla, mandible, sphenoidal, zygomatic, parietal, temporal, and occipital bones can also be affected. Surgical treatment is a major method for craniofacial FD. Total resection of the involved bones and successive craniofacial reconstruction with titanium mesh (TM) are optimal choices of treatment, which could achieve satisfying functional results and favorable aesthetic shape. Recurrence is not common if total removal of the lesion can be achieved. The recurrence and regrowth of craniofacial FD along the repaired TM after total removal are extremely rare. We report a case of recurrent craniofacial FD with extensive
From the Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China. Received July 9, 2013. Accepted for publication November 17, 2013. The authors report no conflicts of interest. Address correspondence and reprint requests to Siqing Huang, MD, Department of Neurosurgery, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu 610041, Sichuan Province, China. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000612
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
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The Journal of Craniofacial Surgery
Brief Clinical Studies
FIGURE 1. Computed tomographic images showing FD involving the frontal bone and TM reconstruction after excising the whole lesion 3 years ago.
TM invasion and encapsulation. To our knowledge, there has not been any previous report about this.
CLINICAL REPORT A 22-year-old man was admitted to our hospital 1 year after a slowly progressive proptosis. And 3 days before the admission, he had a sudden vision loss of the right eye. Craniofacial FD was histologically diagnosed 3 years ago, and the involved frontal bone was totally removed and reconstructed with TM (Fig. 1). The patient recovered well after the first surgery. On admission, the neurological examination revealed exophthalmos, and visual acuity of the right eye was 0.4. A hard, immobile, painless mass over the frontal bone was found. Computed tomography (CT) scan of the brain revealed the lesion regrew from the edges of the excised bone and expanded along TM to the anterior cranial base (Figs. 2A, B). The roof of the right orbit was remarkably thickened, and the right optic nerve canal was clearly narrowed (Fig. 2C). The recurrent lesion partially invaded and wrapped TM on the three-dimensional CT scan image (Fig. 2D). Based on previous medical history, radiographic features, and clinical findings, the recurrence of a craniofacial FD was considered. Aiming at removing recurrent lesions and decompressing the optic canal, a coronal skin incision was performed to expose the frontal lesion. Intraoperatively, we found that the lesion was strikingly tough, and the inner and outer layers of TM were totally wrapped through the holes of the repaired TM (Fig. 3A). Total removal of the affected TM was impossible. As a result, a right pterional craniotomy was performed to resect the thickened orbit roof and decompress the optic canal. The excised lesion was fused with TM and screw (Figs. 3B, C). Histological examination of the lesion revealed benign fibroblastic tissue, which was arranged in a loose, whorled pattern and irregular spicules of woven bone with typical osteoblastic rimming embedded in fibrous tissue. The diagnosis of FD was confirmed. The postoperative course was uneventful. During the following 3 months, the proptosis was gradually relieved, and the visual acuity improved from 0.4 to 0.8.
DISCUSSION Fibrous dysplasia, which was first introduced by Liechtenstein in 1938, is a benign bone disorder characterized by the replacement of normal bone tissue by disorganized proliferation of fibrous tissue.1 The disease mostly occurs in preadolescent patients. However, in some cases, FD continues to grow after puberty.
FIGURE 2. Computed tomographic and three-dimensional CT scans revealing the recurrence of the lesion into TM and the narrowing of the right optic nerve canal.
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FIGURE 3. Intraoperative view. A, the recurrent lesion wrapped the repaired TM. B and C, The excised lesion. Note the thickening and extension due to the lesion and the TM and screw encapsuled by the lesion.
Painless mass is the most common symptom in craniofacial FD, which is frequently associated with facial asymmetry, orbital dystopia, and orbital proptosis.4 Diagnosis of craniofacial FD is based on clinical, radiographic, and histological findings. Computed tomography has been proved to be the most useful in detecting and defining FD lesions of the cranial base.5 A ground-glass appearance on CT scans, thinning of the cortical bone, and ballooning of the affected area are the major hallmarks of FD. Monitoring, conservative surgery, and radical surgery are the 3 general approaches for the treatment of craniofacial FD.2,3 No matter what the treatment option is, the main purpose is to correct or prevent functional problems and achieve normal facial features. However, with rapid advances in surgical techniques and the improvement of artificial materials, more and more neurosurgeons are in favor of radical excision and immediate reconstruction.6,7 Although there are various autogenous and alloplastic reconstructive methods in repair of skull defects, TM reconstruction has become the favorable choice because of its superior properties. Titanium mesh is a satisfying contouring material with features of being tenacious, light, mechanically stable, nonallergenic, and easily shaped and having high biocompatibility. Furthermore, it is associated with few complications and successful permanent integration with minimal fibrous encapsulation rate.9 Wei et al14 reported 81 cases of craniofacial FD, 16 of which had radical excision and immediate cranioplasty with TM. Ten and 4 cases of such situation were also reported by Eldaly et al15 and Cheng et al,16 respectively. Recurrence is not common if the lesion is totally excised. However, there are no reports about the relapse details of craniofacial FD with TM reconstruction. Our case presents the regrowth of craniofacial FD into TM after the first surgery. We assumed that this disease was in the progressive course when the patient underwent the first surgery. Although the involved frontal bone was totally removed, the orbit roof was exposed, and surgical intervention accelerated the regrowth of the possible remnant dysplastic cancellous bone located at the orbit roof. Cancellous bones possess a higher risk of recurrence in osteoconductive lesion.9 During the second surgery, we found that the inner layer of the excised lesion bone was more cancellous and thicker than that of the outer layer, especially between the junction of TM and dysplastic bone. The immature and irregularly shaped woven bone trabecular of FD cannot supply a normal mechanical force for bone growth and is unable to remodel the bone morphology. However, TM with the similar elasticity of the bone provides such mechanical force at the interface where the bone meets titanium. In this way, it enables the dysplastic lesion to form a bone shell to grow along TM. The area between the lesion and TM implant was rich in chemical elements such as C, H, O, Ca, Ti, and so on, and complicated chemical reactions between them may induce and promote new bone growth. In addition, the blood supply of subscalp could nourish this area. Radical excision for those lesions located at superficial skull is achievable, but it is difficult to remove those lesions involving complicated anatomical structure, such as anterior cranial base. One of the most contentious issues is the management of optic canal involvement, particularly in patients with normal vision. Nevertheless, the tendency to proactively decompress the optic nerve is not * 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
recommended in asymptomatic patients, even if radiology has demonstrated optic canal narrowing.17 However, our patient complained of a sudden vision loss, and the coronal CT scan revealed the narrowing of the right optic nerve canal after the first surgery. Improvement of impaired vision after the second surgery demonstrated the efficacy of optic nerve decompression. Although TM reconstruction in craniofacial FD is popular, curative treatment plans should be made because the growth of FD does not follow a well-defined pattern. Although total excision and successive craniofacial reconstruction can be achieved, close follow-up for early diagnosis of relapse is highly recommended.
REFERENCES 1. DiCaprio MR, Enneking WF. Fibrous dysplasia. Pathophysiology, evaluation, and treatment. J Bone Joint Surg Am 2005;87:1848Y1864 2. Chen YR, Noordhoff MS. Treatment of craniomaxillofacial fibrous dysplasia: how early and how extensive? Plast Reconstr Surg 1990;86:835Y842 3. Chen YR, Noordhoff MS. Treatment of craniomaxillofacial fibrous dysplasia: how early and how extensive? Plast Reconstr Surg 1991;87:799Y800 4. Choi JW, Lee SW, Koh KS. Correction of proptosis and zygomaticomaxillary asymmetry using orbital wall decompression and zygoma reduction in craniofacial fibrous dysplasia. J Craniofac Surg 2009;20:326Y330 5. Mendelsohn DB, Hertzanu Y, Cohen M, et al. Computed tomography of craniofacial fibrous dysplasia. J Comput Assist Tomogr 1984;8:1062Y1065 6. Chen M,Yang C, Fang B, et al. Treatment of hemimandibular fibrous dysplasia with radical excision and immediate reconstruction with free double costochondral graft. J Oral Maxillofac Surg 2010;68:2000Y2004 7. Valentini V, Cassoni A, Marianetti TM, et al. Craniomaxillofacial fibrous dysplasia : conservative treatment or radical surgery? A retrospective study on 68 patients. Plast Reconstr Surg 2009;123:653Y660 8. Boni P, Ferri A, Corradi D, et al. Fibro-osseous dysplasia localized to the zygomatic arch: case report. J Craniomaxillofac Surg 2011;39:138Y140 9. Janecka IP. New reconstructive technologies in skull base surgery: role of titanium mesh and porous polyethylene. Arch Otolaryngol Head Neck Surg 2000;126:396Y401 10. Assaf AT, Benecke AW, Riecke B, et al. Craniofacial fibrous dysplasia (CFD) of the maxilla in an 11-year old boy: a case report. J Craniomaxillofac Surg 2012;40:788Y792 11. Ozek C, Gundogan H, Bilkay U, et al. Craniomaxillofacial fibrous dysplasia. J Craniofac Surg 2002;13:382Y389 12. Sakata T, Takahashi K, Kang Y, et al. Repeated surgical reduction of the mandible over a 19-year period due to fibrous dysplasia: a case report. Asian J Oral Maxillofac Surg 2010;22:33Y36 13. Sadeghi SM, Hosseini SN. Spontaneous conversion of fibrous dysplasia into osteosarcoma. J Craniofac Surg 2011;22:959Y961 14. Wei Y, Jiang S, Cen Y. Fibrous dysplasia of skull. J Craniofac Surg 2010;21:538Y542 15. Eldaly A, Nour YA, Ibrahim AA, et al. Radical resection of fibrous dysplasia involving the anterior cranial base. Neurosurg Q 2012;22:126Y132 16. Cheng J, Wang Y, Yu H, et al. An epidemiological and clinical analysis of craniomaxillofacial fibrous dysplasia in a Chinese population. Orphanet J Rare Dis 2012;7:80 17. Schreiber A, Villaret AB, Maroldi R, et al. Fibrous dysplasia of the sinonasal tract and adjacent skull base. Curr Opin Otolaryngol Head Neck Surg 2012;20:45Y52
Brief Clinical Studies
Study of Malignant Peripheral Nerve Sheath Tumor in Cerebellopontine Angle WenMing Hong, MSc,* HongWei Cheng, MD,* XiaoJie Wang, MD,Þ XiaoPeng Hu, MD,þ ChunGuo Feng, BS* Abstract: Malignant peripheral nerve sheath tumors (MPNSTs) are very rare soft tissue sarcomas, usually arising from somatic soft tissues or peripheral nerves. Primary MPNST of the cerebellopontine angle is extremely rare, with only a single case reported so far. Here, we report an unusual case of MPNST in cerebellopontine angle in a 25-year-old man presented with dizziness, left facial numbness, and tinnitus. After hospitalization, the tumor was treated with complete surgical excision followed by adjuvant chemotherapy and radiotherapy. Histologically, the tumor showed malignant spindle cells, which were with focal S-100 positivity on immunohistochemistry, and a diagnosis of the MPNSTwas made. This case is being reported for its rarity and presence in cerebellopontine and illustrated the difficulties in the diagnosis and treatment of MPNST, which to the best of our knowledge, has not been described before in the soft tissue sarcomas. Key Words: Malignant peripheral nerve sheath tumor (MPNST), neurofibrosarcoma, soft tissue sarcoma, cerebellopontine angle (CPA), treatment
T
he term malignant peripheral nerve sheath tumor (MPNST) was coined by the World Health Organization to represent neoplasms, which were previously recognized by terms such as ‘‘malignant neurilemmoma,’’ ‘‘neurofibrosarcoma,’’ ‘‘neurogenic sarcoma,’’ and ‘‘malignant schwannoma.’’ Malignant peripheral nerve sheath tumor with an incidence of 0.001% and a peak incidence in the seventh decade of life in the general population is a rare soft tissue sarcoma arising from the neoplastic transformation of Schwann cells.1,2 Malignant peripheral nerve sheath tumor may arise from any peripheral nerve, and the primary symptoms depend on its anatomic location. Some study of MPNST reported that the largest numbers of tumors were seen in the shoulder, thigh, and pelvis, while with less frequent of occurrence in the thorax, abdomen, hand, forearm, and foot.3 It is evident from the current literature that the intracranial is seldom affected: to our knowledge, there is only 1 published clinical report in cerebellopontine angle (CPA) involvement by MPNST.
From the Departments of *Neurosurgery, †Pathology, and ‡Radiology, First Affiliated Hospital of AnHui Medical University, Hefei, AnHui, China. Received September 21, 2013. Accepted for publication November 27, 2013. Address correspondence and reprint requests to HongWei Cheng, MD, Department of Neurosurgery, First Affiliated Hospital of AnHui Medical University, No. 218 JiXi Rd, Hefei, AnHui 230032, China; E-mail: [email protected] HW Cheng and WM Hong contributed equally to this work. The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000622
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
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& Volume 25, Number 2, March 2014
2. Keller EE. Reconstruction of the severely atrophic edentulous mandible with endosseous implants: a 10-year longitudinal study. J Oral Maxillofac Surg 1995;53:305Y320 3. Papay FA, Zins JE, Hahn JF. Split calvarial bone graft in cranio-orbital sphenoid wing reconstruction. J Craniofac Surg 1996;7:133Y139 4. Donovan MG, Dickerson NC, Hellstein JW, et al. Autologous calvarial and iliac onlay bone grafts in miniature swine. J Oral Maxillofac Surg 1993;51:898Y903 5. Smolka W, Eggensperger N, Carollo V, et al. Changes in the volume and density of calvarial split bone grafts after alveolar ridge augmentation. Clin Oral Implants Res 2006;17:149Y155 6. Vermeeren JI, Wismeijer D, van Waas MA. One-step reconstruction of the severely resorbed mandible with onlay bone grafts and endosteal implants. A 5-year follow-up. Int J Oral Maxillofac Surg 1996;25:112Y115 7. Adell R, Lekholm U, Gro¨ndahl K, et al. Reconstruction of severely resorbed edentulous maxillae using osseointegrated fixtures in immediate autogenous bone grafts. Int J Oral Maxillofac Implants 1990;5:233Y246 8. Nystro¨m E, Legrell PE, Forssell A, et al. Combined use of bone grafts and implants in the severely resorbed maxilla. Postoperative evaluation by computed tomography. Int J Oral Maxillofac Surg 1995;24:20Y25 9. Esposito M, Hirsch JM, Lekholm U, et al. Biological factors contributing to failures of osseointegrated oral implants. (II). Etiopathogenesis. Eur J Oral Sci 1998;106:721Y764 10. Raghoebar GM, Batenburg RH, Timmenga NM, et al. Morbidity and complications of bone grafting of the floor of the maxillary sinus for the placement of endosseous implants. Mund Kiefer Gesichtschir 1999;3:S65YS69 11. Esposito M, Cannizarro G, Soardi E, et al. A 3-year post-loading report of a randomised controlled trial on the rehabilitation of posterior atrophic mandibles: short implants or longer implants in vertically augmented bone? Eur J Oral Implantol 2011;4:301Y311 12. Esposito M, Cannizzaro G, Soardi E, et al. Posterior atrophic jaws rehabilitated with prostheses supported by 6 mm-long, 4 mm-wide implants or by longer implants in augmented bone. Preliminary results from a pilot randomised controlled trial. Eur J Oral Implantol 2012;5:19Y33 13. Keller EE, Tolman DE. Mandibular ridge augmentation with simultaneous onlay iliac bone graft and endosseous implants: a preliminary report. Int J Oral Maxillofac Implants 1992;7:176Y184 14. Neukam FW, Scheller H, Gu¨nay H. Osteo-integrated 2-phase Bra˚nemark implants. Experiments with the therapeutic concept to restore the chewing function in atrophic jaws. Niedersachs Zahnarztebl 1987;22:441Y445 15. Cuesta Gil M, Bucci T, Duarte Ruiz B, et al. Reconstruction of the severely atrophic mandible using autologous calvarial bone graft: an ‘‘inverted sandwich’’ graft technique and dental rehabilitation with fixed implant-supported prostheses. J Craniomaxillofac Surg 2010;38:379Y384 16. Gutta R, Waite PD. Cranial bone grafting and simultaneous implants: a submental technique to reconstruct the atrophic mandible. Br J Oral Maxillofac Surg 2008;46:477Y479 17. Verhoeven JW, Cune MS, Terlou M, et al. The combined use of endosteal implants and iliac crest onlay grafts in the severely atrophic mandible: a longitudinal study. Int J Oral Maxillofac Surg 1997;26:351Y357 18. Chen NT, Glowacki J, Bucky LP, et al. The roles of revascularization and resorption on endurance of craniofacial onlay bone grafts in the rabbit. Plast Reconstr Surg 1994;93:714Y722; discussion 723Y724 19. Iizuka T, Smolka W, Hallermann W, et al. Extensive augmentation of the alveolar ridge using autogenous calvarial split bone grafts for dental rehabilitation. Clin Oral Implants Res 2004;15:607Y615 20. Iturriaga MT, Ruiz CC. Maxillary sinus reconstruction with calvarium bone grafts and endosseous implants. J Oral Maxillofac Surg 2004;62:344Y347
Brief Clinical Studies
Recurring Craniofacial Fibrous Dysplasia With Extensive Titanium Mesh Invasion Honggang Wu, MD, Jin Li, MD, Jianguo Xu, MD, Chao You, MD, Siqing Huang, MD Abstract: The recurrence and regrowth of craniofacial fibrous dysplasia (FD) along the repaired titanium mesh (TM) after total removal are extremely rare. A 22-year-old man was admitted to our hospital complaining of progressive proptosis and sudden vision loss of the right eye. Craniofacial FD was histologically diagnosed 3 years ago, and the involved frontal bone was totally removed and reconstructed with TM in his first surgery. Based on previous medical history, radiographic features, and clinical findings, the recurrence was considered, and the patient underwent surgical treatment. He had an uneventful postoperative course, and during the follow-up, his proptosis was gradually relieved, and the visual acuity also improved. In this article, we present the regrowth of craniofacial FD into TM and describe the clinical features, mechanism, and treatment of this condition. Key Words: Fibrous dysplasia, craniofacial fibrous dysplasia, titanium mesh reconstruction, recurrence, invasion
F
ibrous dysplasia (FD) is a kind of benign, slowly progressive bone lesion with the replacement of normal bone tissues by gradual abnormal proliferation of fibrous tissue, which accounts for about 2.5% of all primary bone masses and 7% of benign bone masses. These lesions may involve a single (monostotic) or multiple bones (polyostotic). Most FDs begin at around 10 years of age and stop progressing after puberty; however, evidence showing lasting growth after adolescence is reported as well.8,10Y12 Craniofacial FD represents 10% to 27% of patients with monostotic FD.13 It may involve all parts of the skull. The most common sites include the frontal, orbital, and ethmoid bones. Maxilla, mandible, sphenoidal, zygomatic, parietal, temporal, and occipital bones can also be affected. Surgical treatment is a major method for craniofacial FD. Total resection of the involved bones and successive craniofacial reconstruction with titanium mesh (TM) are optimal choices of treatment, which could achieve satisfying functional results and favorable aesthetic shape. Recurrence is not common if total removal of the lesion can be achieved. The recurrence and regrowth of craniofacial FD along the repaired TM after total removal are extremely rare. We report a case of recurrent craniofacial FD with extensive
From the Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, Sichuan, China. Received July 9, 2013. Accepted for publication November 17, 2013. The authors report no conflicts of interest. Address correspondence and reprint requests to Siqing Huang, MD, Department of Neurosurgery, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu 610041, Sichuan Province, China. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000612
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
697
The Journal of Craniofacial Surgery
Brief Clinical Studies
FIGURE 1. Computed tomographic images showing FD involving the frontal bone and TM reconstruction after excising the whole lesion 3 years ago.
TM invasion and encapsulation. To our knowledge, there has not been any previous report about this.
CLINICAL REPORT A 22-year-old man was admitted to our hospital 1 year after a slowly progressive proptosis. And 3 days before the admission, he had a sudden vision loss of the right eye. Craniofacial FD was histologically diagnosed 3 years ago, and the involved frontal bone was totally removed and reconstructed with TM (Fig. 1). The patient recovered well after the first surgery. On admission, the neurological examination revealed exophthalmos, and visual acuity of the right eye was 0.4. A hard, immobile, painless mass over the frontal bone was found. Computed tomography (CT) scan of the brain revealed the lesion regrew from the edges of the excised bone and expanded along TM to the anterior cranial base (Figs. 2A, B). The roof of the right orbit was remarkably thickened, and the right optic nerve canal was clearly narrowed (Fig. 2C). The recurrent lesion partially invaded and wrapped TM on the three-dimensional CT scan image (Fig. 2D). Based on previous medical history, radiographic features, and clinical findings, the recurrence of a craniofacial FD was considered. Aiming at removing recurrent lesions and decompressing the optic canal, a coronal skin incision was performed to expose the frontal lesion. Intraoperatively, we found that the lesion was strikingly tough, and the inner and outer layers of TM were totally wrapped through the holes of the repaired TM (Fig. 3A). Total removal of the affected TM was impossible. As a result, a right pterional craniotomy was performed to resect the thickened orbit roof and decompress the optic canal. The excised lesion was fused with TM and screw (Figs. 3B, C). Histological examination of the lesion revealed benign fibroblastic tissue, which was arranged in a loose, whorled pattern and irregular spicules of woven bone with typical osteoblastic rimming embedded in fibrous tissue. The diagnosis of FD was confirmed. The postoperative course was uneventful. During the following 3 months, the proptosis was gradually relieved, and the visual acuity improved from 0.4 to 0.8.
DISCUSSION Fibrous dysplasia, which was first introduced by Liechtenstein in 1938, is a benign bone disorder characterized by the replacement of normal bone tissue by disorganized proliferation of fibrous tissue.1 The disease mostly occurs in preadolescent patients. However, in some cases, FD continues to grow after puberty.
FIGURE 2. Computed tomographic and three-dimensional CT scans revealing the recurrence of the lesion into TM and the narrowing of the right optic nerve canal.
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FIGURE 3. Intraoperative view. A, the recurrent lesion wrapped the repaired TM. B and C, The excised lesion. Note the thickening and extension due to the lesion and the TM and screw encapsuled by the lesion.
Painless mass is the most common symptom in craniofacial FD, which is frequently associated with facial asymmetry, orbital dystopia, and orbital proptosis.4 Diagnosis of craniofacial FD is based on clinical, radiographic, and histological findings. Computed tomography has been proved to be the most useful in detecting and defining FD lesions of the cranial base.5 A ground-glass appearance on CT scans, thinning of the cortical bone, and ballooning of the affected area are the major hallmarks of FD. Monitoring, conservative surgery, and radical surgery are the 3 general approaches for the treatment of craniofacial FD.2,3 No matter what the treatment option is, the main purpose is to correct or prevent functional problems and achieve normal facial features. However, with rapid advances in surgical techniques and the improvement of artificial materials, more and more neurosurgeons are in favor of radical excision and immediate reconstruction.6,7 Although there are various autogenous and alloplastic reconstructive methods in repair of skull defects, TM reconstruction has become the favorable choice because of its superior properties. Titanium mesh is a satisfying contouring material with features of being tenacious, light, mechanically stable, nonallergenic, and easily shaped and having high biocompatibility. Furthermore, it is associated with few complications and successful permanent integration with minimal fibrous encapsulation rate.9 Wei et al14 reported 81 cases of craniofacial FD, 16 of which had radical excision and immediate cranioplasty with TM. Ten and 4 cases of such situation were also reported by Eldaly et al15 and Cheng et al,16 respectively. Recurrence is not common if the lesion is totally excised. However, there are no reports about the relapse details of craniofacial FD with TM reconstruction. Our case presents the regrowth of craniofacial FD into TM after the first surgery. We assumed that this disease was in the progressive course when the patient underwent the first surgery. Although the involved frontal bone was totally removed, the orbit roof was exposed, and surgical intervention accelerated the regrowth of the possible remnant dysplastic cancellous bone located at the orbit roof. Cancellous bones possess a higher risk of recurrence in osteoconductive lesion.9 During the second surgery, we found that the inner layer of the excised lesion bone was more cancellous and thicker than that of the outer layer, especially between the junction of TM and dysplastic bone. The immature and irregularly shaped woven bone trabecular of FD cannot supply a normal mechanical force for bone growth and is unable to remodel the bone morphology. However, TM with the similar elasticity of the bone provides such mechanical force at the interface where the bone meets titanium. In this way, it enables the dysplastic lesion to form a bone shell to grow along TM. The area between the lesion and TM implant was rich in chemical elements such as C, H, O, Ca, Ti, and so on, and complicated chemical reactions between them may induce and promote new bone growth. In addition, the blood supply of subscalp could nourish this area. Radical excision for those lesions located at superficial skull is achievable, but it is difficult to remove those lesions involving complicated anatomical structure, such as anterior cranial base. One of the most contentious issues is the management of optic canal involvement, particularly in patients with normal vision. Nevertheless, the tendency to proactively decompress the optic nerve is not * 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
The Journal of Craniofacial Surgery
& Volume 25, Number 2, March 2014
recommended in asymptomatic patients, even if radiology has demonstrated optic canal narrowing.17 However, our patient complained of a sudden vision loss, and the coronal CT scan revealed the narrowing of the right optic nerve canal after the first surgery. Improvement of impaired vision after the second surgery demonstrated the efficacy of optic nerve decompression. Although TM reconstruction in craniofacial FD is popular, curative treatment plans should be made because the growth of FD does not follow a well-defined pattern. Although total excision and successive craniofacial reconstruction can be achieved, close follow-up for early diagnosis of relapse is highly recommended.
REFERENCES 1. DiCaprio MR, Enneking WF. Fibrous dysplasia. Pathophysiology, evaluation, and treatment. J Bone Joint Surg Am 2005;87:1848Y1864 2. Chen YR, Noordhoff MS. Treatment of craniomaxillofacial fibrous dysplasia: how early and how extensive? Plast Reconstr Surg 1990;86:835Y842 3. Chen YR, Noordhoff MS. Treatment of craniomaxillofacial fibrous dysplasia: how early and how extensive? Plast Reconstr Surg 1991;87:799Y800 4. Choi JW, Lee SW, Koh KS. Correction of proptosis and zygomaticomaxillary asymmetry using orbital wall decompression and zygoma reduction in craniofacial fibrous dysplasia. J Craniofac Surg 2009;20:326Y330 5. Mendelsohn DB, Hertzanu Y, Cohen M, et al. Computed tomography of craniofacial fibrous dysplasia. J Comput Assist Tomogr 1984;8:1062Y1065 6. Chen M,Yang C, Fang B, et al. Treatment of hemimandibular fibrous dysplasia with radical excision and immediate reconstruction with free double costochondral graft. J Oral Maxillofac Surg 2010;68:2000Y2004 7. Valentini V, Cassoni A, Marianetti TM, et al. Craniomaxillofacial fibrous dysplasia : conservative treatment or radical surgery? A retrospective study on 68 patients. Plast Reconstr Surg 2009;123:653Y660 8. Boni P, Ferri A, Corradi D, et al. Fibro-osseous dysplasia localized to the zygomatic arch: case report. J Craniomaxillofac Surg 2011;39:138Y140 9. Janecka IP. New reconstructive technologies in skull base surgery: role of titanium mesh and porous polyethylene. Arch Otolaryngol Head Neck Surg 2000;126:396Y401 10. Assaf AT, Benecke AW, Riecke B, et al. Craniofacial fibrous dysplasia (CFD) of the maxilla in an 11-year old boy: a case report. J Craniomaxillofac Surg 2012;40:788Y792 11. Ozek C, Gundogan H, Bilkay U, et al. Craniomaxillofacial fibrous dysplasia. J Craniofac Surg 2002;13:382Y389 12. Sakata T, Takahashi K, Kang Y, et al. Repeated surgical reduction of the mandible over a 19-year period due to fibrous dysplasia: a case report. Asian J Oral Maxillofac Surg 2010;22:33Y36 13. Sadeghi SM, Hosseini SN. Spontaneous conversion of fibrous dysplasia into osteosarcoma. J Craniofac Surg 2011;22:959Y961 14. Wei Y, Jiang S, Cen Y. Fibrous dysplasia of skull. J Craniofac Surg 2010;21:538Y542 15. Eldaly A, Nour YA, Ibrahim AA, et al. Radical resection of fibrous dysplasia involving the anterior cranial base. Neurosurg Q 2012;22:126Y132 16. Cheng J, Wang Y, Yu H, et al. An epidemiological and clinical analysis of craniomaxillofacial fibrous dysplasia in a Chinese population. Orphanet J Rare Dis 2012;7:80 17. Schreiber A, Villaret AB, Maroldi R, et al. Fibrous dysplasia of the sinonasal tract and adjacent skull base. Curr Opin Otolaryngol Head Neck Surg 2012;20:45Y52
Brief Clinical Studies
Study of Malignant Peripheral Nerve Sheath Tumor in Cerebellopontine Angle WenMing Hong, MSc,* HongWei Cheng, MD,* XiaoJie Wang, MD,Þ XiaoPeng Hu, MD,þ ChunGuo Feng, BS* Abstract: Malignant peripheral nerve sheath tumors (MPNSTs) are very rare soft tissue sarcomas, usually arising from somatic soft tissues or peripheral nerves. Primary MPNST of the cerebellopontine angle is extremely rare, with only a single case reported so far. Here, we report an unusual case of MPNST in cerebellopontine angle in a 25-year-old man presented with dizziness, left facial numbness, and tinnitus. After hospitalization, the tumor was treated with complete surgical excision followed by adjuvant chemotherapy and radiotherapy. Histologically, the tumor showed malignant spindle cells, which were with focal S-100 positivity on immunohistochemistry, and a diagnosis of the MPNSTwas made. This case is being reported for its rarity and presence in cerebellopontine and illustrated the difficulties in the diagnosis and treatment of MPNST, which to the best of our knowledge, has not been described before in the soft tissue sarcomas. Key Words: Malignant peripheral nerve sheath tumor (MPNST), neurofibrosarcoma, soft tissue sarcoma, cerebellopontine angle (CPA), treatment
T
he term malignant peripheral nerve sheath tumor (MPNST) was coined by the World Health Organization to represent neoplasms, which were previously recognized by terms such as ‘‘malignant neurilemmoma,’’ ‘‘neurofibrosarcoma,’’ ‘‘neurogenic sarcoma,’’ and ‘‘malignant schwannoma.’’ Malignant peripheral nerve sheath tumor with an incidence of 0.001% and a peak incidence in the seventh decade of life in the general population is a rare soft tissue sarcoma arising from the neoplastic transformation of Schwann cells.1,2 Malignant peripheral nerve sheath tumor may arise from any peripheral nerve, and the primary symptoms depend on its anatomic location. Some study of MPNST reported that the largest numbers of tumors were seen in the shoulder, thigh, and pelvis, while with less frequent of occurrence in the thorax, abdomen, hand, forearm, and foot.3 It is evident from the current literature that the intracranial is seldom affected: to our knowledge, there is only 1 published clinical report in cerebellopontine angle (CPA) involvement by MPNST.
From the Departments of *Neurosurgery, †Pathology, and ‡Radiology, First Affiliated Hospital of AnHui Medical University, Hefei, AnHui, China. Received September 21, 2013. Accepted for publication November 27, 2013. Address correspondence and reprint requests to HongWei Cheng, MD, Department of Neurosurgery, First Affiliated Hospital of AnHui Medical University, No. 218 JiXi Rd, Hefei, AnHui 230032, China; E-mail: [email protected] HW Cheng and WM Hong contributed equally to this work. The authors report no conflicts of interest. Copyright * 2014 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000000622
* 2014 Mutaz B. Habal, MD
Copyright © 2014 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited.
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