Combined dynamic contrast-enhancement and serial 3D-subtraction analysis in magnetic resonance imaging of osteoid osteomas

A CT-free protocol to treat osteoid osteoma of the hip region in childhood and adolescence by percutaneous drilling and by hip arthroscopy

INTRODUCTION

It is often difficult to clinically and radiologically diagnose intra-articular osteoid osteomas and osteoid osteomas of the hip joint. Treatment can also be difficult due to complex locational relationships. CT-guided radiofrequency ablation is currently the standard form of treatment.In this paper we report on a minimally-invasive concept for treating osteoid osteomas near the hip joint in children and adolescents which does not involve using computed tomography.

MATERIAL AND METHOD

10 patients with an average age of 12.1 years underwent treatment for osteoid osteomas in the hip joint region. The diagnosis was made using a contrast-enhanced MRI. The osteoid osteomas were marked percutaneously using x-ray and MRI guidance. MRI-guided drilling/curettage was performed in 4 cases and arthroscopic resection in 6 cases.

RESULTS

All lesions were successfully treated using the MRI-guided method. All patients were free of pain after the treatment. There was no instance of recurrence during the follow-up period, which averaged 10 months. The effective dose for marking the lesion was between 0.0186 mSv and 0.342 mSV (mean 0.084 mSV).

CONCLUSIONS

Our MRI diagnostics protocol, the MRI-guided drilling and the minimally invasive hip arthroscopy represent an alternative to CT-guided radiofrequency ablation in the treatment of osteoid osteomas. Radiation exposure can thereby be significantly reduced. Hip arthroscopy can also be used to treat secondary pathologies such as femoroacetabular impingement.

Musculoskeletal Applications of Magnetic Resonance-Guided Focused Ultrasound

Magnetic resonance-guided focused ultrasound (MRgFUS) is a novel noninvasive therapy that uses focused sound energy to thermally ablate focal pathology within the body. In the United States, MRgFUS is approved by the Food and Drug Administration for the treatment of uterine fibroids, palliation of painful bone metastases, and thalamotomy for the treatment of essential tremor. However, it has also demonstrated utility for the treatment of a wide range of additional musculoskeletal (MSK) conditions that currently are treated as off-label indications. Advantages of the technology include the lack of ionizing radiation, the completely noninvasive technique, and the precise targeting that offer unprecedented control of the delivery of the thermal dose, as well as real-time monitoring capability with MR thermometry. In this review, we describe the most common MSK applications of MRgFUS: palliation of bone metastases, treatment of osteoid osteomas, desmoid tumors, facet arthropathy, and other developing indications.

Intracortical chondroma of the metacarpal bone: A case report

BACKGROUND

Intracortical chondroma of the metacarpal bone which could be painful is an extremely rare condition and previously only one case has been reported. Due to the similar physical features and appearance on clinical imaging, it is difficult to differentiate between intracortical chondroma and osteoid osteoma. Therefore, pathological examination is usually required to establish a definite diagnosis, which is often carried out only after tumor removal. In this study, we describe a case of intracortical chondroma which developed in the metacarpal bone and demonstrate the utility of magnetic resonance imaging (MRI).

CASE SUMMARY

We present a case of a 40-year-old man with intracortical chondroma of the metacarpal bone who was strongly suspected of having a tumor, and it was confirmed using contrast-enhanced MRI and successfully treated with curettage. MRI performed before tumor removal revealed signal intensity similar to that of the nidus of an osteoid osteoma. However, no abnormal intensity was observed in the bone or soft tissues surrounding the tumor. Such abnormalities on images would indicate the presence of soft-tissue inflammation, which are characteristics of osteoid osteoma. Furthermore, contrast-enhanced imaging revealed no increased enhancement of the areas surrounding the tumor. This is the first report to describe the contrast-enhanced MRI features of intracortical chondroma. This may serve as a guide for clinicians when intracortical chondroma is suspected.

CONCLUSION

The contrast-enhanced MRI was useful for the differential diagnosis of intracortical chondroma.

Intraarticular Osteoid Osteoma: MRI Characteristics and Clinical Presentation Before and After Radiofrequency Ablation Compared to Extraarticular Osteoid Osteoma

PURPOSE

 To determine MRI characteristics and the clinical presentation of intraarticular osteoid osteomas (OO) before and after treatment with CT-guided radiofrequency ablation (RFA) compared with extraarticular osteoid osteomas.

MATERIALS AND METHODS

 In a retrospective study, n = 21 patients with an intraarticular OO were matched with a control group of n = 21 patients with an extraarticular OO at a comparable anatomical position. All patients underwent CT-guided RFA and preinterventional MRI. In n = 31 cases, follow-up MR imaging was available. MR images were analyzed for morphologic features: effusion and synovitis, bone marrow edema (BME), soft tissue edema, periosteal reaction as well as T1 / T2 signal and contrast enhancement of the nidus. Recorded clinical parameters included the initial diagnosis, the course of pain symptoms after RFA and the incidence of complications.

RESULTS

 The nidus was detectable in all patients on MRI. BME had the highest sensitivity in both intra- and extraarticular OO (100 %). Effusion and synovitis were only observed in the intraarticular OO group (n = 21) with a perfect sensitivity and specificity (100 %) and a high negative predictive value (85 %). Soft tissue edema was significantly more present in patients with intraarticular OO (p = 0.0143). No significant differences were present regarding periosteal reaction, T1/T2 signal and contrast enhancement of the nidus (p > 0.05). BME, contrast enhancement, soft tissue edema, periosteal reaction, effusion and synovitis, if preexisting, always decreased after RFA. In 66.7 % of patients with intraarticular OO, a false initial diagnosis was made (extraarticular: 19 %). All patients were free of pain after intervention. Complications following the RFA procedure did not occur.

CONCLUSION

 MRI demonstrates the nidus and thus the OO in all cases regardless of the location. The characteristic MRI morphology of an intraarticular OO includes synovitis and joint effusion, which are always present and differentiate with perfect sensitivity/specificity from an extraarticular OO. In both intra- and extraarticular OOs pathologic MRI changes at least decreased or completely normalized and the clinical results after RFA were excellent.

KEY POINTS

  · MRI is excellently suited for the diagnosis of intra- and extraarticular OOs.. · Joint effusion and synovitis distinguish both forms with perfect sensitivity and specificity.. · All MRI changes, which indicate activity, decreased after successful RFA.. · The clinical results after RFA are excellent in both forms..

CITATION FORMAT

· Germann T, Weber M, Lehner B et al. Intraarticular Osteoid Osteoma: MRI Characteristics and Clinical Presentation Before and After Radiofrequency Ablation Compared to Extraarticular Osteoid Osteoma. Fortschr Röntgenstr 2020; 192: 1190 - 1198.

Osteoid osteoma of the hip: imaging features

Osteoid osteoma (OO), a small bone tumor relatively common in young subjects, frequently involves the hip. In addition to typical findings, we emphasize unsuspected clinical and imaging features including painless OO causing limping gait, non-visibility of totally mineralized nidus, absence of hyperostosis or adjacent edema, and recurrence at distance from the initial location. We also discuss the option of medical treatment for some cases of deep hip locations.

Resection of a Rare Metacarpal Distal Condyle Osteoid Osteoma

Introduction

Osteoid osteoma is a benign bone-forming tumor with young male predilection. It occurs predominantly in the long bones. In the hand, osteoid osteoma is more commonly located in the phalanges and carpal bones. The metacarpals are the least common site for osteoid osteoma. Pain is the most common symptom. It usually increases at night and responds to nonsteroidal anti-inflammatory drugs.

Case Presentation

The authors report the excision of an osteoid osteoma lying at the distal condyle of a metacarpal bone of the left hand. The clinical and radiological findings are exposed as well as the surgical management of the lesion. Pain and swelling disappeared after surgery, and there was no evidence of recurrence at follow-up.

Discussion

They discuss this rare location and further radiological examination that was used leading to the diagnosis. The imputation of the traumatic factor has been discussed, along with the different therapeutic possibilities and the advantages of a total excision while preserving the integrity of the adjacent ligament and joint space.

Conclusion

The surgical alternative appears to be a satisfying treatment for osteoid osteoma in this particular superficial location. Both the exact pathogenesis and the contribution of the traumatic factor remain unclear.

Bone tumours around the elbow: a rare entity

Bone tumours around the elbow are rare. Even nowadays diagnostic dilemmas and delays are common. During recent decades the management and prognosis of patients with elbow bone tumours has improved significantly.Benign tumours can be treated using minimally invasive procedures, whereas malignant ones require a multidisciplinary team approach based on an adjuvant therapeutic regimen of chemotherapy, radiotherapy and limb salvage procedures.This article reviews the most commonly encountered elbow bone tumours and their management. Cite this article: EFORT Open Rev 2019;4:133-142. DOI: 10.1302/2058-5241.4.180086.

Osteoid osteoma: multimodality imaging with focus on hybrid imaging

Osteoid osteoma is a painful, benign, osteoblastic lesion that occurs in younger patients and affects the extremities or the axial skeleton. While plain film findings may suggest the diagnosis, in complex anatomical regions such as the spine, pelvis, wrist and foot advanced imaging modalities are often required. A typical nidus surrounded by sclerosis or cortical thickening characterizes osteoid osteoma on plain radiography and CT. MR is the cross-sectional imaging modality of choice for most musculoskeletal disorders. Unfortunately, extensive accompanying bone marrow oedema, soft-tissue alterations, difficulty detecting the nidus, and lesion locations close to a joint (with reactive arthritis) may make a confident diagnosis of osteoid osteoma by MR imaging difficult. Hybrid imaging with bone-seeking tracers such as SPECT/CT with ^99mTc-labelled bisphosphonates or PET/CT with ¹⁸F-labelled sodium fluoride (¹⁸F-NaF) combines high radionuclide uptake with morphological details and provides accurate diagnosis of osteoid osteoma and additional information for treatment planning. FDG is not the recommended PET tracer because osteoid osteoma is normally FDG-negative, although some osteoid osteomas may show increased FDG uptake. Osteoblastoma, Brodie's abscess and stress fractures may mimic osteoid osteoma on imaging and clinical presentation. Once identified as the pain generator, destruction of the osteoid osteoma nidus by ablation or resection techniques usually leads to complete healing. Image-guided drill excision and radiofrequency ablation are widely used interventions. We review the presentation of osteoid osteoma across all imaging modalities, with special focus on hybrid imaging techniques.

Osteoid osteoma: Contemporary management

Osteoid osteoma is a benign bone-forming tumor with hallmark of tumor cells directly forming mature bone. Osteoid osteoma accounts for around 5% of all bone tumors and 11% of benign bone tumors with a male predilection. It occurs predominantly in long bones of the appendicular skeleton. According to Musculoskeletal Tumor Society staging system for benign tumors, osteoid osteoma is a stage-2 lesion. It is classified based on location as cortical, cancellous, or subperiosteal. Nocturnal pain is the most common symptom that usually responds to salicyclates and non-steroidal anti-inflammatory medications. CT is the modality of choice not only for diagnosis but also for specifying location of the lesion, i.e. cortical vs sub periosteal or medullary. Non-operative treatment can be considered as an option since the natural history of osteoid osteoma is that of spontaneous healing. Surgical treatment is an option for patients with severe pain and those not responding to NSAIDs. Available surgical procedures include radiofrequency (RF) ablation, CT-guided percutaneous excision and en bloc resection.

Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics

OBJECTIVE

To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO).

MATERIALS AND METHODS

Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Slope_rise) and CT variables were the bone and segment involved (OO_bone and OO_segment, respectively), OO location relative to the native cortex (OO_cortex), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmax_vessel). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed.

RESULTS

DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Slope_rise of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmax_vessel of 1.10 ± 0.60 mm. By univariate analysis, Slope_rise correlated significantly with pain duration and Dmax_vessel (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Slope_rise correlated significantly with OO_bone (P < 0.001), with a steeper slope for OOs located in short or flat bones.

CONCLUSION

This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones.

Sclerotic lesions of the spine: MRI assessment

Sclerotic (T2 dark) lesions of the spine are infrequent and, as a result, these are often missed or misdiagnosed. Plain films may not be always available during magnetic resonance imaging (MRI) readout. Knowledge of such lesions and their imaging appearances on MRI evaluation is essential for a reader. Additionally, a systematic approach is important to accurately diagnose these lesions. In this article we discuss the various causes of spinal sclerotic lesions, describe their MRI characteristics with relevant case examples, and outline a systematic approach to their evaluation.

Osteoid osteoma: MR-guided focused ultrasound for entirely noninvasive treatment

PURPOSE

To determine the preliminary feasibility, safety, and clinical efficacy of magnetic resonance (MR)-guided focused ultrasound for the treatment of painful osteoid osteoma.

MATERIALS AND METHODS

This prospective institutional review board-approved study involved six consecutive patients (five males and one female; mean age, 21 years) with a diagnosis of osteoid osteoma based on clinical and imaging findings. All patients underwent MR-guided focused ultrasound ablation after providing informed consent. Lesions located in the vertebral body were excluded. The number of sonications and the energy deposition were recorded. Treatment success was determined at 1, 3, and 6 months after treatment. A visual analog scale (VAS) score for pain was used to assess changes in symptoms. MR imaging features of osteoid osteoma (edema, hyperemia, and nidus vascularization) were considered at baseline and at imaging follow-up.

RESULTS

Treatment was performed with a mean of 4 sonications ± 1.8 (standard deviation), with a mean energy deposition of 866 J ± 211. No treatment- or anesthesia-related complications occurred. The pre- and posttreatment mean VAS scores significantly differed (7.9 ± 1.4 and 0.0 ± 0.0, respectively). At imaging, the edema and hyperemia associated with osteoid osteoma gradually disappeared in all lesions. However, nidus vascularization still persisted after treatment in four of six patients.

CONCLUSION

This limited series demonstrated that MR-guided focused ultrasound treatment of osteoid osteoma can be performed safely with a high rate of success and without apparent treatment-related morbidity.

Osteoid osteomas: a pain in the night diagnosis

Osteoid osteoma is a common benign bone-forming lesion that is composed of a nidus of vascular osteoid tissue and woven bone lined by osteoblasts. It is frequently associated with considerable surrounding inflammation. The diagnosis is usually straightforward when imaging reveals a radiolucent nidus surrounded by variable degrees of reactive sclerosis. However, the diagnosis can be elusive when osteoid osteomas occur in atypical locations, as they may have a nonspecific and misleading appearance on different imaging modalities, particularly on MRI. The purpose of this pictorial essay is to review the typical and atypical features of osteoid osteomas on different imaging modalities, and the appearance of osteoid osteomas in different locations. We also review growth disturbances caused by osteoid osteomas and potential mimickers, with imaging characteristics that can aid in diagnosis.

Dificuldades diagnósticas no osteoma osteoide do cotovelo: estudo clínico, radiológico e histopatológico

OBJETIVO: Descrever os aspectos clínicos e de imagem que podem auxiliar no diagnóstico correto do osteoma osteoide no cotovelo. MATERIAIS E MÉTODOS: Realizado estudo retrospectivo de sete pacientes com diagnóstico de osteoma osteoide no cotovelo confirmado histologicamente por biópsia óssea. Eles tiveram seus prontuários médicos e exames de imagem revisados. RESULTADOS: Do total de 142 pacientes identificados em nossos arquivos, 4,9% apresentavam a lesão no cotovelo, com predomínio no sexo masculino (2,5:1) e idade média de 25 anos. Dor e limitação de movimento foram os sintomas mais comuns. Cinco pacientes (71,4%) receberam outro diagnóstico clínico prévio. A duração média dos sintomas foi de 21 meses. As radiografias não demonstraram o nidus em 42,8% dos casos. A tomografia computadorizada e a ressonância magnética mostraram claramente o nidus. Derrame articular foi um achado constante. O aspecto histológico observado foi o usual. A ressecção cirúrgica promoveu alívio dos sintomas e/ou melhora funcional em todos os casos. CONCLUSÃO: É importante considerar a possibilidade de osteoma osteoide em paciente adulto jovem com dor, limitação do movimento e sinais de sinovite no cotovelo, refratária ao tratamento conservador. Esclerose óssea, espessamento cortical e/ou reação periosteal detectados na radiografia permitem direcionar a tomografia computadorizada para a visualização precisa do nidus.

Osteoid osteoma--the CT vessel sign

OBJECTIVE

To evaluate whether the presence of a feeding vessel in proximity to osteoid osteomas of long bones on multidetector CT (MDCT) can be an adjuvant clue for the diagnosis of osteoid osteoma.

MATERIALS AND METHODS

Forty-nine CT scans of patients with radiological and clinical diagnosis of osteoid osteoma of long bones and a control group of 20 CT scans of patients with cortical-based lesions other then osteoid osteoma were analyzed. Two radiologists evaluated the CT images in consensus for the presence of a blood vessel in the same axial slices in which the nidus of osteoid osteoma was seen and to determine the incidence.

RESULTS

In 39 cases (79.6%) of osteoid osteoma, a blood vessel either entered the nidus (23 patients) or was seen in proximity to it (16 patients). This was significantly different (P < 0.05) from the cortical-based lesions, in which only two CT scans (10%) showed a blood vessel in the lesion's proximity.

CONCLUSION

In the majority of osteoid osteoma lesions in long bones, a blood vessel can be seen on MDCT either entering the nidus itself or in its proximity. The role of this vessel in the lesion pathogenesis and whether it improves diagnostic accuracy need further evaluation.

Intra-articular osteoid osteoma simulating a painful fabella syndrome

We present a case of an intra-articular osteoid osteoma in the knee that was mistaken for a painful fabella syndrome after unsuccessful knee arthroscopy for the treatment of postero-lateral knee pain. In this case both the initial clinical presentation and the imaging proved to be deceiving. The diagnosis of intra-articular osteoid osteoma was considered only once typical clinical features appeared and a Computerized Tomography scan was performed. We discuss the difficult of diagnosing an intra-articular osteoid osteoma and the imaging of choice.

Osteoid osteoma and osteoid osteoma-mimicking lesions: biopsy findings, distinctive MDCT features and treatment by radiofrequency ablation

OBJECTIVE

To report the biopsy findings of osteoid osteoma (OO) and OO-mimicking lesions, assess their distinctive multidetector computed tomography (MDCT) features and evaluate treatment by radiofrequency ablation (RFA).

METHODS

In this multicentric retrospective study, 80 patients (54 male, 26 female, mean age 24.1 years, range 5-48) with presumed (clinical and MDCT features) OO were treated by percutaneous RFA between May 2002 and June 2009. Per-procedural biopsies were always performed. The following MDCT features were assessed: skeletal distribution and location within the bone, size, central calcification, surrounding osteosclerosis and periosteal reaction. Clinical success of RFA was evaluated.

RESULTS

Histopathological diagnoses were: 54 inconclusive biopsies, 16 OO, 10 OO-mimicking lesions (5 chronic osteomyelitis, 3 chondroblastoma, 1 eosinophilic granuloma, 1 fibrous dysplasia). OO-mimicking lesions were significantly greater in size (p = 0.001) and presented non-significant trends towards medullary location (p = 0.246), moderate surrounding osteosclerosis (p = 0.189) and less periosteal reaction (p = 0.197), compared with OO. Primary success for ablation of OO-mimicking lesions was 100% at 1 month, 85.7% at 6 and 12 months, and 66.7% at 24 months. Secondary success was 100%.

CONCLUSION

Larger size, medullary location, less surrounding osteosclerosis and periosteal reaction on MDCT may help differentiate OO-mimicking lesions from OO. OO-mimicking lesions are safely and successfully treated by RFA.