|Year : 2019 | Volume
| Issue : 3 | Page : 137-139
Giant Schwannoma of the ulnar nerve compressing ulnar artery
Gokay Baykara, Galip Gencay Ustun, Koray Gursoy, Muzaffer Caydere
Department of Plastic, Reconstructive and Aesthetic Surgery, Ankara Research and Training Hospital, Ankara, Turkey
|Date of Web Publication||4-Jul-2019|
Dr. Gokay Baykara
Ankara Research and Training Hospital, Ulucanlar Cd. Ankara Egitim ve Arastirma Hastanesi, 06230 Altindag, Ankara
Source of Support: None, Conflict of Interest: None
Schwannomas are peripheral nerve tumors that have a relatively slow-growing pattern usually presenting with compressing symptoms. Treatment is excision of mass, but it is important to decide whether radical excision/nerve grafting or nerve-sparing surgery using intra/extracapsular approach should be performed. Besides that, scarification or preservation of nerve fascicles inside the capsule should be considered during surgery. A case with a giant Schwannoma of the ulnar nerve is presented. Tumor was excised using intracapsular approach enabling salvaging of ulnar artery and healthy ulnar nerve fascicles. Patient's early and late postoperative neurological examination did not show any decline compared to preoperative examination. Intracapsular excision makes preservation of healthy fascicles possible while allowing total excision of the mass. Scarification of the fascicles inside the neural sheath of the tumor results in no neurological deficit. The aim of this study is presenting a case diagnosed in the late course with accompanying neural and vascular pathologies, and reviewal of possible treatment methods for maximizing neurological outcome while minimizing relapse.
Keywords: Intracapsular excision, neurological deficit, Schwannoma, ulnar nerve
|How to cite this article:|
Baykara G, Ustun GG, Gursoy K, Caydere M. Giant Schwannoma of the ulnar nerve compressing ulnar artery. Turk J Plast Surg 2019;27:137-9
| Introduction|| |
Schwannomas are common peripheral nerve tumors comprising 8% of soft tissue tumors seen in upper extremity. Third to fifth decades of life is the most common time zone for patient presentation. In 95% of cases, Schwannomas are solitary, but multiple tumors have also been reported. During differential diagnosis, due to relatively low incidence in Eastern countries, there is a possibility of misdiagnosis as tenosynovitis, ganglion cyst, or other soft tissue tumors.
Schwannomas located in extremities arise predominantly from major peripheral nerves, with the most common nerve of origin being the median nerve and the ulnar nerve. These tumors can also be seen in rare sites such as toe, suprascapular region, or even the intraventricular region. In short, it can develop wherever there is Schwann cell.
The tumor has a slowly growing pattern that is encapsulated without an evidence of infiltration. History, clinical examination, imaging, and histopathological examination take part during diagnosis of these tumors. Clinical symptoms first appear as a result of compression of the accompanying nerve and surrounding soft tissues. Treatment is excision of mass using microsurgical methods for functional preservation. It is important to decide whether nerve-sparing surgery using intra/extracapsular approach or radical excision/nerve grafting should be performed. A patient with a 10 mm × 6 cm mass originating from ulnar nerve is presented.
| Case Report|| |
An 88-year-old male patient presented with a giant mass in the right elbow. He has a history of hypertension, diabetes mellitus, and dementia.
Mass in the volar surface was measured to be 10 cm × 6 cm and has been growing for about 15 years. The sensory examination was suboptimal and could not be successfully performed due to dementia. Motor examination showed 4+ strength at 4th and 5th finger flexion and adduction. Ulnar artery could not be palpated. In the computed tomography, a 95 mm × 54 mm × 52 mm smooth-contoured homogeneous hypoechoic solid mass was observed overlying muscle fascia [Figure 1]. Doppler ultrasonography showed and ulnar artery was compressed by mass effect.
The operation was performed under tourniquet control using loupe magnification. Intraoperative exploration showed an encapsulated mass exerting pressure on the nerve fascicles within the ulnar nerve sheath [Figure 2]. Ulnar artery was compressed and attenuated due to compression [Figure 3]. After dissection of the soft tissue surrounding ulnar artery and nerve, the operation was carried out using operating microscope. Ulnar artery was dissected from the mass without disturbing the blood flow. After that, examination of ulnar nerve showed attenuated nerve fascicles running on the surface of the tumor without an interruption [Figure 4]. Due to the patient's age, possible nerve graft regeneration potential, well encapsulation of tumor, nerve sparing, and intracapsular excision of the tumor was performed [Figure 5]. Fascicles that took the course within the tumor were sacrificed with the tumor. Early and late neurological examinations showed no deficit what so ever after the operation.
|Figure 4: After dissection of the running ulnar nerve fascicles on the surface of the tumor|
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| Discussion|| |
Even though Schwannomas are benign, noninfiltrative, slow-growing lesions; with enough time and growth, neurological deficits may be encountered. Therefore, early diagnosis and treatment is important.
The elective treatment of Schwannomas is the enucleation of the tumor by microdissection from the originating nerve. During enucleation, it is important to decide whether to use extracapsular or intracapsular dissection.
According to the results of a study comparing the occurrence of neurological deficits after the extracapsular and intracapsular enucleation of upper extremity Schwannoma, postoperative neurological deficit rate is lower with the intracapsular enucleation. In addition to other articles favoring intracapsular enucleation,, a recent review shows that among all other surgical techniques, intracapsular excision seems to have better results about the preservation of nerve function. So even if the mass has suspicion of malignancy, intracapsular excision should be preferred at initial stage.
Decision to whether sacrifice nerve fascicles inside the tumor is a matter of concern even with intracapsular enucleation technique. Some authors claim resection of the fascicle inside the sheath of the tumor may cause a major neurological deficit. However, using electromyography and postoperative results, it has been shown that these fascicles are already nonfunctional. Transient neurological deficits can be seen in 82% of patients who have undergone intracapsular enucleation. Even with fascicle preservation, facing this complication may be explained with damaging small fascicles during tumor excision, pressure of the tumor causing atrophy of healthy nerve fibers, and neuropraxia.
In some delayed cases, as a result of tumor growth, fascicle dissection cannot be performed, and in this condition, the patient requires radical excision. As a result, the possibility of permanent motor and neurological deficits in the patient is considerably high. Reconstructive options such as nerve grafts and muscle transfer may be considered in these cases.
| Conclusion|| |
Although they usually present as small and asymptomatic masses of the body, peripheral nerve tumors may also be diagnosed in the late course with accompanying clinical symptoms with Schwannomas being the most common.
With the theoretical potential of growing anywhere in the body, in upper extremity, median and ulnar nerves are the most common sites of origination. However, mass could be palpated through the skin due to lack of natural body cavities in this region and neurological symptoms are noticed in the early phase due to the frequent use of the hand. Giant tumors as in our case are extremely rare due to these causes.
After diagnosis, choosing the right surgical technique for excision Schwannomas is important for cure of the patient and functional preservation. Intracapsular excision seems to be the standard of care, but if it cannot be performed, the surgeon may consider other surgical options. Even though it is possible to preserve fascicles, in some cases, scarification of the fascicles involved in the tumor is inevitable. In these situations, neurological deficit risk is very low.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]