Prolonged heating in nontargeted tissue during MR-guided focused ultrasound of bone tumors.

BACKGROUND: Thermal dosimetry during MR-guided focused ultrasound (MRgFUS) of bone tumors underpredicts ablation zone. Intraprocedural understanding of heat accumulation near bone is needed to prevent undesired treatment of nontargeted tissue. HYPOTHESIS: Temperature decay rates predict prolonged, spatially varying heating during MRgFUS bone treatments. STUDY TYPE: Prospective case series. PATIENTS: Nine patients with localized painful bone tumors (five bone metastasis, four osteoid osteomas), were compared with five patients with uterine fibroid tumors treated using MRgFUS. FIELD STRENGTH/SEQUENCE: Proton resonance frequency shift thermometry using 2D-GRE with echo-planar imaging at 3 T. ASSESSMENT: Tissue response was derived by fitting data from extended thermometry acquisitions to a decay model. Decay rates and time to peak temperature (TTP) were analyzed in segmented zones between the bone target and skin. Decay rates were used to calculate intersonication cooling times required to return to body temperature; these were compared against conventional system-mandated cooling times. STATISTICAL TESTS: Kolmogorov-Smirnov tests for normality, and Student's t-test was used to compare decay rates. Spatial TTP delay and predicted cooling times used Wilcoxon signed rank tests. P < 0.05 was significant. RESULTS: Tissue decay rates in bone tumor patients were 3.5 times slower than those in patients with fibroids (τbone = 0.037 ± 0.012 vs. τfibroid = 0.131 ± 0.010, P < 0.05). Spatial analysis showed slow decay rates effecting baseline temperature as far as 12 mm away from the bone surface, τ4 = 0.015 ± 0.026 (median ± interquartile range [IQR]). Tissue within 9 mm of bone experienced delayed TTP (P < 0.01). In the majority of bone tumor treatments, system-predicted intersonication cooling times were insufficient for nearby tissue to return to body temperature (P = 0.03 in zone 4). DATA CONCLUSION: MRgFUS near bone is susceptible to long tissue decay rates, and unwanted cumulative heating up to 1.2 cm from the surface of the bone. Knowledge of decay rates may be used to alter treatment planning and intraprocedural thermal monitoring protocols to account for prolonged heating by bone. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2019;50:1526-1533.

[An update for the treatment of osteoid osteoma]. / Le point sur le traitement percutané des ostéomes ostéoïdes.

Osteoid osteoma is frequent benign tumor, descripted initially by Bergstrand in 1930 followed by Jaffe in 1935. The painful feature of the osteoid osteoma explains the specific consideration by the medical community for this entity. The debate was focused on pathologic and imaging pattern as well as the treatment modalities. Currently, the treatment options are varied and percutaneous treatment is increasingly used. The radiofrequency is widely validated as efficient method without serious adverse and with low rate of recurrence. We hope through this this work to revue the current knowledge of the treatment of osteoid osteoma.

L'ostéome ostéoïde est une tumeur osseuse bénigne relativement fréquente initialement décrite par Bergstrand en 1930, puis comme une entité propre grâce aux recherches de Jaffe en 1935. Malgré sa bénignité, elle a concentré toute l'attention des radiologues comme des cliniciens car très symptomatique. Dès lors, l'ostéome ostéoïde a fait l'objet de nombreux débats dans la communauté scientifique en particulier concernant son étiologie, ses caractéristiques pathologiques, son bilan d'imagerie et son traitement. C'est sur cette dernière question que les avancées ont été les plus marquantes et c'est ainsi que les possibilités thérapeutiques bien décrites dans la littérature apparaissent variées. Toutefois, les résultats très favorables des traitements percutanés et en particulier de la radiofréquence, de même que le faible taux de récidives et de complications de ces traitements, ont amené de nombreux pays à les considérer comme le meilleur traitement en première intention. A travers cette revue de la littérature et de notre pratique clinique, nous souhaitons rapporter les connaissances actuelles thérapeutiques en perpétuelle progression grâce au progrès technique.

Cystic bone tumors of the foot and ankle.

Bone tumors are relatively rare in the foot and ankle region. Many of them present as cystic lesions on plain films. Due to the relative rarity of these lesions and the complex anatomy of the foot and ankle region, identification of such lesions is often delayed or they get misdiagnosed and mismanaged. This review discusses the most common cystic tumors of the foot and ankle including their radiographic features and principles of management.

Technical aspects of osteoid osteoma ablation in children using MR-guided high intensity focussed ultrasound.

BACKGROUND: Osteoid osteoma (OO) is a painful bone tumour occurring in children and young adults. Magnetic resonance imaging-guided high intensity focussed ultrasound (MR-HIFU) allows non-invasive treatment without ionising radiation exposure, in contrast to the current standard of care treatment with radiofrequency ablation (RFA). This report describes technical aspects of MR-HIFU ablation in the first 8 paediatric OO patients treated in a safety and feasibility clinical trial (total enrolment of up to 12 patients). MATERIALS AND METHODS: OO lesions and adjacent periosteum were treated with MR-HIFU ablation in 5-20 sonications (sonication duration = 16-48 s, frequency = 1.2 MHz, acoustic power = 20-160 W). Detailed treatment workflow, patient positioning and coupling strategies, as well as temperature and tissue perfusion changes were summarised and correlated. RESULTS: MR-HIFU ablation was feasible in all eight cases. Ultrasound standoff pads were shaped to conform to extremity contours providing acoustic coupling and aided patient positioning. The energy delivered was 10 ± 7 kJ per treatment, raising maximum temperature to 83 ± 3 °C. Post ablation contrast-enhanced MRI showed ablated volumes ranging 0.46-19.4 cm3 extending further into bone (7 ± 4 mm) than into soft tissue (4 ± 6 mm, p = 0.01, Mann-Whitney). Treatment time ranged 30-86 min for sonication and 160 ± 40 min for anaesthesia. No serious treatment-related adverse events were observed. Complete pain relief with no medication occurred in 7/8 patients within 28 days following treatment. CONCLUSIONS: MR-HIFU ablation of painful OO appears technically feasible in children and it may become a non-invasive and radiation-free alternative for painful OO. Therapy success, efficiency, and applicability may be improved through specialised equipment designed more specifically for extremity bone ablation.

Targetability of osteoid osteomas and bone metastases by MR-guided high intensity focused ultrasound (MRgHIFU).

PURPOSE: To retrospectively evaluate the suitability of MRgHIFU for osteoid osteomas (OOs) and bone metastases in patients who underwent minimally-invasive percutaneous thermal ablation. MATERIALS AND METHODS: One hundred and sixty-seven lesions (115 metastases and 52 OOs) treated percutaneously between October 2014 and June 2017 were retrospectively analyzed. Tumors were located in the spine or sacrum (54), pelvis (43), limbs (50), ribs (17) and sternum (3). Tumor volume, matrix, anatomical environment and need for protection of surrounding structures or consolidation were assessed. Cases were classified into three categories: (a) lesions suitable for MRgHIFU therapy alone; (b) lesions suitable for MRgHIFU if protection of surrounding structures and/or bone consolidation is performed; (c) lesions not suitable for MRgHIFU. RESULTS: Twenty-six (50%) of OOs were classified as suitable for MRgHIFU alone and 17 (32.7%) as suitable for MRgHIFU with hydro-dissection. Matrix of treatable OOs was sclerotic (19), lytic (15) or mixed (9), with mean volume 0.56 cm3. Forty-one (35.7%) of metastases were classified as suitable for MRgHIFU alone and 43 (37.4%) as suitable with hydro-dissection and/or consolidation. Matrix of metastases was sclerotic (13), lytic (37) or mixed (34), with mean volume 71.9 cm3. Mean depth of targetable lesions was 50.9 ± 28.4 mm. 97.7% of pelvic lesions and 94% of peripheral bone lesions were targetable by HIFU. 66.6% of spinal or sacral lesions were considered untreatable. CONCLUSION: MRgHIFU cannot be systematically performed non-invasively on bone tumors. Combination with minimally-invasive thermo-protective techniques may increase the number of eligible cases.

Ribbing disease: a systematic review.

Background Ribbing disease, or multiple diaphyseal sclerosis, is a rare benign bone dysplasia. Purpose To systematically review the literature to determine the clinical and radiological presentation of patients with Ribbing disease as well as the effects of attempted treatments. Material and Methods We considered individual patient data of patients diagnosed with Ribbing disease derived from patient reports and patient series. All stages of the review were performed by two reviewers independently. Standard descriptive statistics were used for quantitative analyses and mixed model analyses were used when appropriate Results The literature search yielded 420 unique hits of which 23 studies were included, covering a total of 40 patients of whom 29 had bilateral involvement. The mean age at diagnosis was 35 years and the mean time between diagnosis and onset of symptoms, mostly pain, was five years (range = 1-16 years). The tibial diaphysis was the most commonly involved bone in 35 of 36 patients. Non-surgical treatment consisted of non-steroidal anti-inflammatory drugs (NSAIDs), prednisone, and bisphophonates with mixed results. Surgical treatment consisted of intramedullary reaming and fenestration and was very effective to reduce pain. Conclusion The clinical presentation and imaging findings of patients with Ribbing disease are becoming more apparent. However, there is paucity of evidence on the natural disease progression and effectiveness of treatment modalities.

Noninvasive Therapy for Osteoid Osteoma: A Prospective Developmental Study with MR Imaging-guided High-Intensity Focused Ultrasound.

Purpose To demonstrate that magnetic resonance (MR) imaging-guided high-intensity focused ultrasound (HIFU) is a safe, effective, and durable treatment option for the management of osteoid osteoma in children and young adults. Materials and Methods This prospective study was institutional review board approved and is registered with clinicaltrials.gov (identification number NCT02302651). Written informed consent was obtained from patients or their parents. Patients who had both clinical and radiologic findings that were diagnostic for nonvertebral osteoid osteoma and no contraindications to MR imaging-guided HIFU were enrolled between June 2010 and June 2013. The feasibility, safety, and clinical effectiveness of MR imaging-guided HIFU were considered primary outcomes; tumor control at imaging was considered a secondary outcome. Analyses were conducted on a per-protocol basis. Results Forty-five of the 50 recruited patients underwent MR imaging-guided HIFU. All patients were discharged without treatment-related complications. The median visual analog scale (VAS) pain score (scale, 0-10) decreased from 8 before treatment to 0 at 1-week and 1- , 6- , 12- , 24- , and 36-month follow-up. Similarly, median VAS scores for the degree to which pain interfered with sleep and physical and daily activities decreased to 0 within the 1st month after treatment and remained stable at subsequent follow-up. Overall, 39 (87%) of the 45 patients achieved and maintained a VAS score of 0 during the 3-year observation period. Quality of life, as assessed by using Functional Assessment of Cancer Therapy-Bone Pain (FACT-BP) scores (scale, 0-60 points), improved, with the median FACT-BP score of 28 (points) before treatment increasing to a median score of 55 at 1-week follow-up and 60 at 6-month and subsequent follow-ups. At (final) 36-month follow-up, MR imaging depicted an absence of residual nidus vascularity in 32 (76%) of the 42 patients who were treated with MR imaging-guided HIFU only. Conclusion The durable clinical efficacy and safety of MR imaging-guided HIFU were demonstrated. These features are evidence of the potential of MR imaging-guided HIFU to be part of a routine strategy for the treatment of osteoid osteoma. © RSNA, 2017.

[The intraarticular osteoid osteoma : A diagnostic and therapeutic challenge]. / Das intraartikuläre Osteoidosteom : Eine diagnostische wie therapeutische Herausforderung.

Intra- and, respectively, periarticular osteoid osteoma are accompanied by sympathical arthritis which itself can irreversibly destroy the cartilage of the joint. In contrast to other locations, intra- and periarticular osteoid osteoma are rare. Reactive and symptomatic accompanying arthritis may lead to irreversible cartilage destruction especially in chronic courses. Therefore early diagnosis and therapy is crucial. We present a case report and discuss these rare tumors by reviewing the literature.

Riddles in the diagnosis and treatment of osteoid osteoma in child foot: A concisive study.

BACKGROUND: Osteoid osteoma in child foot is very unusual. We investigate its polymorphism and difficulties in approach. METHODS: We retrospectively studied 12 children (7 girls, 5 boys) treated in our department from February 1995 until February 2010. Mean age was 12 years (range 8-16 years) and average follow up time 5 years (3-8 years). The lesion affected mostly the talus (8 cases), calcaneus in 3 and once the fourth metatarsal. En bloc excision of lesion was the surgical method of choice. RESULTS: Children's symptoms lasted average 2 years (14 months to even 4 years). Nocturnal pain and relief with NSAIDs occurred only in half cases. Atypical symptoms were hip referring pain, tenosynovitis of foot extensors and achilles' tendon atrophy. Complete cure and no recurrencies were noted. CONCLUSIONS: Diversity of symptoms and delay in diagnosis still remain troublesome and the absolute modality of treatment for child foot osteoid osteomas urges further investigation. Minimally invasive surgical techniques have recently emerged but orthopaedic surgeons must not forget that open excision remains the most safe and documented method for pediatric foot osteoid osteomas.

Intra- and periarticular osteoid osteoma: Percutaneous destruction and alcoholisation.

Intra- or periarticular osteoid osteoma (00) is uncommon, and therefore a diagnostic challenge. Symptoms are: chronic synovitis, decreased range of motion, joint effusion, and joint contracture. Radiographically, the classical perifocal sclerotic margin is often absent, which leads to a significant delay in diagnosis. The authors retrospectively studied 50 cases of intra- and peri-articular OO, treated with percutaneous destruction and alcoholisation. The mean follow-up period was 8.7 years (range, 1 to 15 years). The diagnosis was only made after +/-14 months (range, 8 to 18 months), due to atypical symptoms (nightly pain absent in 38%) and uselessness of plain radiographs (in 100%). CT-scan, contrast enhanced MRI and bone scan brought the solution. The technique was successful in 48 out of 50 cases (96%): incomplete excision occurred in 2 patients. The diagnosis of intra- or periarticular OO should be considered in case of unexplained joint pain where conservative treatment is inefficient.

Diagnosis failure led to the recurrence of an intra-articular osteoid osteoma at the talus neck after arthroscopic excision.

Juxta-articular localization is not exceptional for an osteoid osteoma of the ankle. Arthroscopic treatment has been recently proposed. A case of recurrence of an osteoid osteoma at the talar neck is reported after arthroscopic resection performed following a diagnosis failure. The need for accurate imaging technique to precisely define and localize the nidus and the requirement to include osteoid osteoma in the differential diagnosis of monoarticular pain are discussed.

High-intensity focused ultrasound-a needleless management for osteoid osteoma: a systematic review.

Osteoid osteoma is one of the most frequent benign musculoskeletal neoplasm. Radiofrequency ablation is the method of choice for non-conservative treatment of osteoid osteoma. Recently, high-intensity focused ultrasound (HIFU) has been proposed as a safer option. The objective of this study is to review the efficacy and side effects of HIFU in the management of osteoid osteoma. A comprehensive search was conducted in PubMed, Science Direct, and Clinical Key until June 30, 2022. Demographic data, baseline characteristics, success rates, pre- and post-procedure pain scores, recurrences, and complications were recorded. Eleven studies were included in this systematic review. Pooled analysis that involved 186 subjects resulted in an overall success rate of 91.94%. Recurrence was reported in two studies, in which it occurred in 4/177 (2.26%) subjects. Skin burn was found in 1 (0.54%) patients. No major or other complications were reported. Three studies compared the success rate of HIFU and RFA. Success rate was slightly higher in the RFA group with insignificant difference (p = 0.15). High-intensity focused ultrasound showed promising results. It offers a safer treatment approach for osteoid osteoma, especially in children, and can be considered for recalcitrant cases after RFA. Nonetheless, more studies are expected in the future.

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.

Dynamic MR imaging of osteoid osteomas: correlation of semiquantitative and quantitative perfusion parameters with patient symptoms and treatment outcome.

OBJECTIVE: To evaluate the relationship between multiple MR perfusion parameters and symptoms of patients with osteoid osteomas after percutaneous laser therapy. METHODS: MR perfusion studies of 20 patients diagnosed with an osteoid osteoma, treated with CT-guided percutaneous laser therapy, were retrospectively evaluated. Multiple perfusion parameters correlated with the treatment outcome and the presence of osteoid osteoma-related symptoms. RESULTS: There were 16 successful treatments, 6 recurrences and a significant difference in the perfusion parameters of these groups (P < 0.0001). Patients with successful treatment demonstrated delayed progressive enhancement or no enhancement (mean time to peak = 182 s, mean delay to the arterial peak = 119.3 s). Patients with treatment failure demonstrated an early and steep enhancement (mean time to peak = 78 s and mean delay to the arterial peak = 24 s). Plasmatic volume and transfer constant values significantly changed after successful treatment (P < 0.008). MR perfusion has a sensitivity and a specificity higher than 90 % in the detection of recurrent osteoid osteomas. CONCLUSION: The identification of an early and steep enhancement with short time to peak and a short delay between the arterial and nidus peaks on MR perfusion in the postoperative setting is highly indicative of an osteoid osteoma recurrence. Key points • Magnetic resonance perfusion is becoming widely used for several tumours. • MR perfusion measurements correlate well with osteoid osteoma-related symptoms. • MR perfusion has high diagnostic performance for osteoid osteoma recurrence. • MR perfusion can improve the diagnostic confidence of osteoid osteoma recurrence.

Resolving bony abnormality evolves to diffuse large B-cell lymphoma.

Primary lymphoma of bone is a rare malignancy that can mimic infection and benign bone lesions radiographically. Malignant conversion of osseous lesions has been reported; evolution to lymphoma has not. We describe an adolescent male diagnosed with atypical osteoid osteoma who, despite near resolution of bony changes involving the anterior tibia, was diagnosed with monostotic diffuse large B-cell lymphoma four years later. Indolent lymphoma of the initial lesion is unlikely. This case highlights the importance of clinical suspicion of malignancy even with recurrence of similar clinical presentation and hints at possible osseous microenvironment abnormalities predisposing to the development of lymphoma.

Pediatric bone imaging: diagnostic imaging of osteoid osteoma.

OBJECTIVE: Osteoid osteomas are benign painful skeletal neoplasms that preferentially afflict young male patients and are readily treatable. This article focuses on the various imaging manifestations of the tumor, while also discussing its clinical presentation, pathogenesis, and treatment. CONCLUSION: Knowledge of the common imaging features of osteoid osteomas will improve our diagnosis of this condition, subsequently facilitating treatment and reducing morbidity.

Benign tumors of the spine.

Benign tumors in the spine include osteoid osteoma, osteoblastoma, aneurysmal bone cyst, osteochondroma, neurofibroma, giant cell tumor of bone, eosinophilic granuloma, and hemangioma. Although some are incidental findings, some cause local pain, radicular symptoms, neurologic compromise, spinal instability, and deformity. The evaluation of spinal tumors includes a thorough history and physical examination, imaging, sometimes laboratory evaluation, and biopsy when indicated. Appropriate treatment may be observational (eg, eosinophilic granuloma) or ablative (eg, osteoid osteoma, neurofibroma, hemangioma), but generally is surgical, depending on the level of pain, instability, neurologic compromise, and natural history of the lesion. Knowledge of the epidemiology, common presentation, imaging, and treatment of benign bone tumors is essential for successful management of these lesions.

Particular imaging features and customized thermal ablation treatment for intramedullary osteoid osteoma in pediatric patients.

OBJECTIVE: To report on the particular imaging features and high success rate of cold mode radio-frequency thermal ablation (RFTA) as the treatment of choice for intramedullary osteoid osteoma. MATERIALS AND METHODS: The study population consisted of 51 patients (39 males, 12 females; mean age 7.2 years; 11 patients under 6 years of age, including 7 males and 4 females) who underwent RFTA for osteoid osteoma and were retrospectively observed. The affected sites were the tibia (n = 22, 43%), femur (n = 13, 25%), pelvis (n = 5, 10%), anklebone (n = 3, 6%), humerus (n = 2, 4%), sacrum (n = 2, 4%), heel, radium, patella ,and rib (n = 1, 2%), respectively. Three patients had tibial intramedullary osteoid osteoma (14% of the tibial lesions, 6% of all cases). Cold mode RFTA was performed for these three patients to obtain a large ablation area without positioning two probes. The noncooled mode was used to treat cortical and subperiosteal lesions. RESULTS: Following RFTA, all patients were pain-free and in good clinical condition. In the intramedullary osteoid osteoma group, no recurrences were observed during the 24-month follow-up period, but one patient, who was affected by cortical osteoid osteoma, required two RFTA treatments to heal completely. CONCLUSION: Children less than 6 years of age with recurrent nocturnal pain and limb swelling should be investigated for intramedullary osteoid osteoma. Once confirmed, CT-guided RFTA should be the first treatment for intramedullary osteoid osteomas because of the high success rate and reduced invasivity, especially with cold mode RFTA. The outcome is related to the disappearance of pain, and the efficacy may be checked shortly after treatment with MR imaging to evaluate the absence of lesion in the ablation area.

[Monarthritis of the ankle due to osteoid osteoma of the talus. Difficulties in diagnosis and treatment]. / Monarthritis des oberen Sprunggelenks bei Osteoidosteom des Talus. Schwierigkeiten bei Diagnose und Therapie.

The case of a 22-year-old man with an osteoid osteoma of the right talus neck is reported. After 2 years of pain and swelling we confirmed the diagnosis by CT and MRI scan. Afterwards we performed CT-guided thermocoagulation; 12 months afterwards the patient shows no symptoms anymore.