Arteriovenous malformation of bone: an experience with therapeutic embolization

A Case of an Aggressive Intraosseous Arteriovenous Malformation in the Lower Extremity: Special Considerations for Diagnosis and Management

BACKGROUND

Arteriovenous malformations (AVMs) are rare, congenital vascular anomalies. Intraosseous AVMS most frequently arise in the head and neck, with only a small fraction occurring in the extremities. Herein, we report the findings of a combined soft tissue and intraosseous AVM involving the lower extremity of a 13-year-old child. This case highlights the necessity of an interdisciplinary approach for the effective treatment and management of these rare vascular anomalies.

CASE DESCRIPTION

A 13-year-old female presented with a 4-year history of intermittent pain and swelling over her right lateral malleolus. The patient was evaluated with radiologic imaging revealing an AVM involving the right distal leg, ankle, and hindfoot with intraosseous involvement of the distal tibia and talus. She was then referred to Vascular and Plastic Surgery and an angiogram was performed demonstrating shunting from the anterior tibial, peroneal, and posterior tibial arteries to the AVM. Venous drainage was to the anterior tibial and greater saphenous veins. Three embolizations were performed over the course of 6 months. Following the third embolization, the patient was taken to the operating room where Plastic and Orthopedic Surgery performed total resection of the nidus and involved bone which was then grafted with injectable synthetic bone graft.

RESULTS

Successful resection of the nidus was achieved, and the patient had an uncomplicated recovery. Within 6 months postoperatively, the patient demonstrated full range of lower extremity motion and was able to participate in age appropriate gross motor activities. Radiologic evaluation 7 months postoperatively showed no evidence of nidus recurrence.

CONCLUSION

Intraosseous involvement of AVMS is rare and presents a therapeutic challenge due to its invasive potential and high incidence of recurrence. Wide local excision with bone grafting and interdisciplinary management are paramount for complete resection.

Diagnosis and conservative treatment of a rare case of femoral intraosseous arteriovenous malformation in a patient with polyostotic fibrous dysplasia: A case report

Pure intraosseous arteriovenous malformation (AVM) in a limb bone is extremely rare. Furthermore, there is currently insufficient information on the diagnostic and therapeutic strategies for pure intraosseous AVMs. We herein report a case of pure intraosseous AVM of the proximal femur occurring in a patient with polyostotic fibrous dysplasia. The patient was a 39-year-old woman who presented with pain in the right thigh. Plain radiographs and computed tomography scans revealed a medullary lytic lesion with expansion and thinning of the bone cortex in the right proximal femur, mimicking a primary bone tumor. Magnetic resonance imaging (MRI) examination revealed intramedullary signal voids and feeding arteries arising from the deep femoral artery. A non-surgical approach using embolization and denosumab achieved satisfactory results, which included complete obliteration of the AVM, increased cortical thickness of the right proximal femur, and attenuation of the high-turnover bone metabolism 1 year later. Careful review of MRI images is crucial for distinguishing between bone tumors and intraosseous AVM, which exhibit signal voids and feeding arteries, in order to avoid unnecessary interventions such as bone biopsy or surgery.

A Rare Case of Distal Humerus Intraosseous Arteriovenous Malformation

Introduction:

Primary intraosseous arteriovenous malformations (AVMs) are rare and have only been occasionally reported. We herein report a histologically proven case of primary intraosseous AVM in the distal humerus which mimicked an osteomyelitis on radiography.

Case Report:

A 27-year-old male presented with complaints of the right elbow pain and stiffness for the past 3 years. He had initially taken treatment at an outside hospital where he was suspected to have right distal humerus osteomyelitis and underwent curettage and biopsy in June 2017. He presented to us in August 2018 with persistent pain even following the first surgery. Repeat radiographs and computed tomography of the right elbow showed features of osteolytic lesion involving the right lateral humeral condyle just adjacent to olecranon fossa (Fig. 1 and 2). Through posterior triceps, splitting approach para-olecranon lesion was resected by intralesional method (burring), and vancomycin-impregnated calcium sulfate (Stimulan) beads were packed in the defect as infection was suspected (Fig. 3). Clinical improvement and restoration of full range of elbow motion were observed on follow-up. Biopsy report surprisingly suggested arteriovenous malformation.

Conclusion:

Osteolytic lesion was localized in the lateral margin of the olecranon fossa (Fig. 2a and b). To reach the lesion during surgery was a major challenge as localization of the lesion was missed out by the previous surgery. The occurrence of such a condition is rare and it may take even years to correctly diagnose the disease.

Imaging features of an intraosseous arteriovenous malformation in the tibia

Primary intraosseous arteriovenous malformations (AVMs) are rare and have only been occasionally reported. We herein report a histologically proven case of primary intraosseous AVM in the tibia, which mimicked a fibrous tumour on radiography. This presentation carries a risk of triggering acute large haemorrhage through unnecessary biopsy. In intraosseous AVM, the magnetic resonance (MR) imaging features typical of a soft tissue AVM are absent, making diagnosis difficult. In this report, peculiar MR features in the presence of a connecting vessel between the normal deep venous system of the lower extremity and the tumour provide a clue for the early diagnosis of primary intraosseous AVM.

Preoperative transarterial Embolisation in bone tumors

Bone tumors include a variety of lesions, both primary and metastatic. The treatment modalities for bone tumors vary with the individual lesion, but in general surgical excision is the treatment of choice with other adjunctive therapies. However, surgery for many bone tumors is complex due to several factors including tumor bulk, vascularity, vicinity to vital structures and potentially inaccessible location of the lesion. Transarterial Embolisation (TAE) is one of the important adjuvant treatment modalities and in some cases it may be the primary and curative treatment. Preoperative TAE has proved to be effective in both primary and metastatic bone tumors. It reduces tumor vascularity and intraoperative blood loss, the need for blood transfusion and associated complications, allows better definition of tissue planes at surgery affording more complete excision, and hence reduced recurrence. Preoperative chemoEmbolisation has also been shown to increase the sensitivity of some tumors to subsequent chemotherapy and radiotherapy. There are several techniques and embolic agents available for this purpose, but the ultimate aim is to achieve tumor devascularization. In this review, we discuss the techniques including the choice of embolic agent, application to individual lesions and potential complications.

Embolization of musculoskeletal bone tumors

Bone tumors may present as incidental findings, with pain or loss of function, or as fractures. There is a broad range of indications for transarterial embolization (TAE) in primary or metastatic bone tumors: to reduce operative hemorrhagic risks, to simplify or allow more definitive surgery, or in the context of pain palliation, fever, bleeding, or hypercalcemic and other rheological factors. Embolization may also increase tumor sensitivity to chemotherapy or radiation therapy. The procedure itself is often complex with significant risk to adjacent structures and is usually part of a wider treatment strategy. There are many options of embolic agent, techniques, and end points but all aim to devascularize the tumor. Catheter angiography at the time of TAE is used to determine the correct embolic agent and technique with care taken to isolate at risk structures. Many factors determine the best choice of embolic material, probably the most important of which is operator experience. In life-threatening situations or in preoperative embolizations of metastatic tumors, many operators opt for a combination of particulate emboli and stainless steel or platinum coils. Agents discussed include polyvinyl alcohol particles, trisacryl microspheres, gelatin sponge, liquid embolic agents, and embolization coils. Tumor types treated include vascular metastatic lesions, commonly renal cell or thyroid, particularly in locations prone to fracture; giant cell tumors; aneurysmal bone cysts; vertebral hemangiomas, osteosarcomas; arteriovenous malformations; and osteoblastomas. TAE should be considered in the treatment algorithm of primary or secondary bone tumors. Specific benefit is present where there is a high risk of bleeding at surgery, where there is spinal involvement and neural encroachment, where active bleeding is present or in awkward surgical locations where prolonged surgery is anticipated.

Selective arterial embolisation for bone tumours: experience of 454 cases

PURPOSE

The authors present the experience of a single institution with selective arterial embolisation for primary and metastatic bone tumours.

MATERIALS AND METHODS

A total of 365 patients were treated with 454 embolisation procedures from December 2002 to April 2010. Embolisation was the primary treatment for benign bone tumours, adjuvant treatment to surgery for benign and malignant bone tumours and palliative treatment for bone sarcomas and metastases. Indications for repeat embolisation included pain or imaging evidence of progressive disease: 105 patients had repeat embolisation at the same location at an interval of 1-3 months; 260 patients had one embolisation, 78 had two and 29 had three or more. In all patients, N-2-butyl cyanoacrylate (NBCA) in 33% lipiodol was the embolic agent used.

RESULTS

A total of 419 of the 454 embolisations (93%) were technically successful. In 35 cases, embolisation was not feasible because of poor lesion vascularisation (21 patients with bone metastases and two with aneurysmal bone cysts), origin of the Adamkiewicz artery in the embolisation field (four patients with bone metastases and one with aneurysmal bone cyst), atheromatosis and arteriosclerosis (five patients with bone metastases) and anatomical and technical problems such as small-calibre vessels, many branches and acute vessel angles (two patients with bone metastases). A clinical response was achieved in 406 of the 419 procedures (97%), and no response in 13 procedures in patients with pelvis and sacrum tumours. Complications included postembolisation syndrome in 81 patients (22%), transient paraesthesias in 41 (11%), skin breakdown and subcutaneous necrosis at the shoulder and pelvis in five (1.4%) and paresis of the sciatic nerve in one (0.3%).

CONCLUSIONS

We recommend embolisation as primary or palliative treatment or an adjunct to surgery for tumours of variable histology. Strict adherence to the principles of transcatheter embolisation is important. Arteries feeding the tumour and collaterals must be evaluated carefully and catheterised superselectively to protect the normal tissues. NBCA is considered the most appropriate embolic agent for small-vessel occlusion without major complications.

Unusual causes of varicose veins in the lower extremities: CT venographic and Doppler US findings

There are various causes of varicose veins in the lower extremities. Among the causes are venous insufficiency of the saphenofemoral junction, saphenopopliteal junction, or usual perforating veins. Traditionally, Doppler ultrasonography (US) has been used for evaluation of varicose veins. Sometimes, varicose veins arise from an unexpected anatomic source; in these cases, computed tomographic (CT) venography can provide an overview of the varicose veins. Doppler US with complementary CT venography is useful for determining the precise cause of varicose veins. Between November 2003 and March 2008, the authors evaluated 1350 cases of varicose veins in the lower extremities with both CT venography and Doppler US. The varicose veins were classified according to their causes; unusual causes were studied and included vulvoperineal varicosity, intraosseous perforating vein incompetence, round ligament varicosity, persistent sciatic vein incompetence, Klippel-Trenaunay syndrome, and portosystemic collateral pathways. Radiologists should be familiar with the complete range of primary causes of varicose veins in the lower extremities and with their radiologic manifestations and should recognize the complementary role of CT venography in their evaluation.

Clinicopathologic features and results of transcatheter arterial chemoembolization for osteosarcoma

PURPOSE

To evaluate the effect of transcatheter arterial chemoembolization (TACE) for osteosarcoma and to describe the clinicopathologic features produced by TACE as well as the effect of different embolic materials.

METHODS

From January 1998 to December 2003, preoperative TACE was carried out in 32 patients. The preoperative and postoperative clinical response, levels of alkaline phosphatase (AKP), leukocyte count, and clinicopathologic features were recorded. We also compared the effect of different embolic materials: adriblastine gelatin microspheres, anhydrous alcohol, common bletilla tuber, and gelatin sponge particles.

RESULTS

The levels of AKP were significantly decreased after treatment (p < 0.05), but there was no significant difference in the leukocyte count. Large areas of necrosis were found histologically within 85.5% tumors after TACE. Embolic agents such as adriblastine microspheres, anhydrous alcohol, and common bletilla tuber have better clinical effects than gelatin sponge particles, but there was no significant difference among the first three embolic materials. After treatment, no serious complications were noted. During successful follow-up for 86 months, the survival rate after TACE at 1, 2, and 5 years was 95.5%, 72%, and 42% respectively.

CONCLUSION

TACE accelerated tumor necrosis and shrank the tumor volume, thus making adequate tumor resection possible. The optimal time to operate is 10-14 days after TACE. TACE in combination with limb salvage surgery and postoperative periodical chemotherapy may be beneficial for increasing local control rates.

Transcatheter arterial embolization for malignant osseous and soft tissue sarcomas. II. Clinical results

PURPOSE

To evaluate the clinical effects of transcatheter arterial embolization (TAE) on malignant bone and soft tissue tumors.

METHODS

TAE was performed in 10 patients with primary bone and soft tissue sarcomas and in 31 patients with metastatic bone tumors. The embolized arteries were the internal iliac artery in 30 cases, the intercostal artery in six cases, the lumbar artery in five cases, the suprascapular artery in three cases, and the iliolumbar artery, the internal pudendal artery, and the lateral sacral artery in one case each. The embolized material was gelatin sponge particles. The chemotherapeutic drugs were usually 20-40 mg of doxorubicin for primary and metastatic tumors and 50-100 mg of cisplatin only for primary tumors. In addition, 50-60 Gy of 10-MV radiotherapy with or without radiofrequency (RF)-capacitive hyperthermia in four sessions was administered before TAE for primary tumors only.

RESULTS

Even though the pain score increased immediately after TAE, 30 of 38 (79%) patients with pain (8 of 9 with primary tumors, and 22 of 29 with metastases) achieved pain control after TAE. A necrotic low-density area shown by computed tomography (CT) after TAE was found in 31 of 41 (76%) tumors [8 of 10 (80%) with primary tumors, and 23 of 31 (74%) with metastatic tumors]. The tumor size decreased in 14 of 25 (56%) primary and metastatic tumors after 3 months. Osteosclerotic changes appeared in two cases of metastatic tumors after 6 months. In five tumors resected after TAE, large areas of necrosis within the tumor were confirmed histologically. Transient local pain and numbness appeared after TAE, but were relieved by drug treatment within 1 week. No severe complications except a case of gluteal muscle necrosis were encountered after TAE. The 1-year survival rate of the patients with primary tumors was 38.1%, and the median survival was 18 months. The longest survival was 84 months. The 1-year survival rate of the patients with metastatic bone tumors was 38.9%; the median survival was 12 months. The longest survival was 24 months.

CONCLUSION

TAE could be an effective treatment for pain control and local control of malignant bone and soft-tissue tumors.

Transcatheter arterial embolization for malignant osseous and soft-tissue sarcomas. I. A rabbit experimental model

PURPOSE

To evaluate the effect of transcatheter arterial embolization (TAE) on metastatic bone tumors in an experimental study.

METHODS

Fifteen Japanese white rabbits were transplanted with VX2 sarcoma cells into the iliac crest. In 10 rabbits, the arterial supply to the iliac bone tumors, internal iliac artery and iliolumbar artery were then embolized with particles of gelatin sponge. The therapeutic effect was evaluated by comparison with the natural course of control tumors in the other five rabbits.

RESULTS

After TAE, extensive necrosis, fibrosis, and vacuolization within the tumors were confirmed histologically. In the control rabbits, 19% +/- 7% of the entire tumor was found to be spontaneous tumor necrosis; in contrast, the tumors of the TAE group showed necrosis as 62% +/- 22% of the entire tumor. In one TAE group rabbit, no active tumor cell could be detected in the residual tumor.

CONCLUSION

TAE was found to be an effective treatment for bone tumors in an experimental model.

Osseous metastases from hepatocellular carcinoma: embolization for pain control

Transcatheter arterial embolization for osseous metastasis of hepatocellular carcinoma (HCC) was performed in 7 patients. The embolization therapy was used in patients in whom the feeding artery could be catheterized. All tumors were accompanied by abundant neovascularity and tumor stain. Embolization was successfully performed in 5 patients, all of whom became symptom free within a week. The only complication was local pain which was controlled by nonnarcotic pain medication. Embolization may be a useful treatment method for osseous metastasis of HCC.