Diagnostic Efficacy and Clinical Impact of Image-guided Core Needle Biopsy of Suspected Vertebral Osteomyelitis

OBJECTIVES

The diagnostic yield and clinical impact of image-guided core needle biopsy(ICNB) of suspected vertebral osteomyelitis in adults is heterogenous in published studies due to small sample size, indicating the need for large cohort studies.

METHODS

A retrospective analysis of ICNBs was performed from 2010-2021 for patients with imaging findings consistent with vertebral osteomyelitis. For each biopsy, a series of factors were analyzed, as well as if histopathology was diagnostic of osteomyelitis and if microbiological cultures were positive. Additionally, it was recorded in what way biopsy influenced clinical management regarding antimicrobial treatment. Multivariate statistical analysis was performed to evaluate the factors associated with yield.

RESULTS

A total of 570 biopsies performed on 527 patients were included. A histopathologic diagnosis of osteomyelitis was made in 68.4%(359/525) of biopsies, and microbiological cultures were positive in 29.6%(169/570). Elevated ESR was positively associated with a histopathologic diagnosis of osteomyelitis(OR=1.96, p=0.007), and positive cultures from bone cores(OR=1.02,p=<0.001) and aspirate(OR=1.02,p=<0.001). Increased total core length was positively associated with a histopathologic diagnosis of osteomyelitis(OR=1.81,p=0.013), and positive cultures from bone cores (OR=1.65,p=0.049). Clinical management was affected by ICNB in 37.5%(214/570) of cases.

CONCLUSION

In this large cohort, ICNB yielded approximately 30% positive cultures and changed clinical management in over one-third of patients.

Essentials of Spinal Tumor Ablation

Recent advances in percutaneous minimally invasive thermal ablation and vertebral augmentation provide radiologists with important arsenal for treatment of selected patients with spinal metastases. These interventions have proven to be safe, effective, and durable in treatment of selected patients with vertebral metastases. Attention to procedure techniques, including choice of ablation modality, vertebral augmentation technique, and thermal protection, is essential for improved patient outcomes. A detailed knowledge of such interventions and implementation of procedural safety measures will further heighten radiologists' role in the management of patients with spinal metastases.

Diagnostic efficacy of image-guided core needle biopsy of suspected malignant osseous lesions: a retrospective cohort study from a single academic institution

OBJECTIVES

To evaluate diagnostic yield and accuracy of image-guided core needle biopsy (ICNB) of suspected malignant osseous lesions in a large cohort of adults, evaluate what factors influence these measures, and offer technical recommendations to optimize yield.

METHODS

A retrospective analysis of 2321 ICNBs performed from 2010 to 2021 was completed. The diagnostic yield and accuracy of the biopsies as well as a series of patient, lesion-related, and technical factors were retrospectively analyzed. Multivariate statistical analysis was performed to evaluate what factors were associated with yield and accuracy. Different cutoff values of total core length and core number were then tested to determine threshold values in relation to increased diagnostic yield.

RESULTS

Diagnostic yield was 98.2% (2279/2321) and accuracy was 97.6% (120/123). Increased total core length (odds ratio [OR] = 2.34, 95% confidence interval [CI] (1.41-3.90), p = 0.001), core number (OR = 1.51, 95% CI (1.06-2.16), p = 0.02) and presence of primary malignancy (OR = 2.81, 95% CI (1.40-5.62), p = 0.004) were associated with improved yield. Lesion location in an extremity (OR = 0.27, 95% CI (0.11-0.68), p = 0.006) and using fluoroscopic imaging guidance (OR = 0.33, 95% CI (0.12-0.90), p = 0.03) were associated with lower yield. Cutoff thresholds in relation to increased diagnostic yield were found to be 20 mm total core length (marginal OR = 4.16, 95% CI = (2.09-9.03), p < 0.001), and three total cores obtained (marginal OR = 2.78, 95% CI (1.34-6.54), p = 0.005). None of the analyzed factors influenced diagnostic accuracy.

CONCLUSIONS

ICNB has a high rate of diagnostic yield and accuracy. Several factors influence diagnostic yield; 20 mm core length and three total cores optimize yield.

CLINICAL RELEVANCE STATEMENT

Image-guided core needle biopsy of suspected malignant osseous lesions is a safe procedure with a very high rate of diagnostic yield and accuracy. Obtaining 20 mm total core length and three total cores optimizes diagnostic yield.

KEY POINTS

• In a retrospective cohort study, image-guided core needle biopsy of suspected osseous malignant lesions in adults was found to have very high rates of diagnostic yield and accuracy. • Increased total core length and core number of biopsies were each associated with increased diagnostic yield, and these relationships reached thresholds at 20 mm total core length and three total cores obtained. • The presence of a known primary malignancy was also associated with increased yield while using fluoroscopic imaging guidance and lesion location in an extremity were associated with decreased yield.

Beyond Average: α-Particle Distribution and Dose Heterogeneity in Bone Metastatic Prostate Cancer

α-particle emitters are emerging as a potent modality for disseminated cancer therapy because of their high linear energy transfer and localized absorbed dose profile. Despite great interest and pharmaceutical development, there is scant information on the distribution of these agents at the scale of the α-particle pathlength. We sought to determine the distribution of clinically approved [223Ra]RaCl2 in bone metastatic castration-resistant prostate cancer at this resolution, for the first time to our knowledge, to inform activity distribution and dose at the near-cell scale. Methods: Biopsy specimens and blood were collected from 7 patients 24 h after administration. 223Ra activity in each sample was recorded, and the microstructure of biopsy specimens was analyzed by micro-CT. Quantitative autoradiography and histopathology were segmented and registered with an automated procedure. Activity distributions by tissue compartment and dosimetry calculations based on the MIRD formalism were performed. Results: We revealed the activity distribution differences across and within patient samples at the macro- and microscopic scales. Microdistribution analysis confirmed localized high-activity regions in a background of low-activity tissue. We evaluated heterogeneous α-particle emission distribution concentrated at bone-tissue interfaces and calculated spatially nonuniform absorbed-dose profiles. Conclusion: Primary patient data of radiopharmaceutical therapy distribution at the small scale revealed that 223Ra uptake is nonuniform. Dose estimates present both opportunities and challenges to enhance patient outcomes and are a first step toward personalized treatment approaches and improved understanding of α-particle radiopharmaceutical therapies.

Benign Bone Tumors Beyond Osteoid Osteoma: Percutaneous Minimally Invasive Image-Guided Interventions

Painful benign bone tumors often adversely influence quality of life primarily due to skeletal-related events such as unremittable pain, pathologic fracture, neurologic deficit, as well as skeletal growth disturbance. Substantial advances in percutaneous minimally invasive interventions for treatment of painful benign bone tumors beyond osteoid osteoma have been established as safe, efficacious, and durable treatments to achieve definitive cure. This article details the available armamentarium and most recent advances in minimally invasive percutaneous interventions and the role of radiologists for the management of patients with benign bone tumors beyond osteoid osteoma.

Spine metastases: thermal ablation and augmentation

Substantial advances in percutaneous minimally invasive musculoskeletal oncologic interventions including thermal ablation and vertebral augmentation offer a robust armamentarium for interventional radiologists for management of patients with spinal metastases. Such interventions have proved safe and effective in management of selected patients with vertebral metastases. Special attention to procedure techniques including choice of ablation modality, vertebral augmentation technique, and thermal protection is essential for improved patient outcomes. Familiarity with the described interventions and implementation of procedural safety measures will further enhance the role of radiologists in the management of patients with spinal metastases. This article provides a review of the most recent advances in thermal ablation and vertebral augmentation as well as the role of radiologists for treatment of spinal metastases.

Percutaneous Treatment of Spinal Metastases

Percutaneous image-guided minimally invasive thermal ablation and vertebral augmentation are robust techniques, part of the available armamentarium used by radiologists for the management of patients with spinal metastases. Such interventions have been established to be safe and effective in treatment of selected patients with vertebral metastases. Special attention to procedure techniques including choice of ablation modality, vertebral augmentation technique, and thermal protection is essential for improved patient outcomes.

ACR Appropriateness Criteria® Management of Vertebral Compression Fractures: 2022 Update

Vertebral compression fractures (VCFs) can have a variety of etiologies, including trauma, osteoporosis, or neoplastic infiltration. Osteoporosis related fractures are the most common cause of VCFs and have a high prevalence among all postmenopausal women with increasing incidence in similarly aged men. Trauma is the most common etiology in those >50 years of age. However, many cancers, such as breast, prostate, thyroid, and lung, have a propensity to metastasize to bone, which can lead to malignant VCFs. Indeed, the spine is third most common site of metastases after lung and liver. In addition, primary tumors of bone and lymphoproliferative diseases such as lymphoma and multiple myeloma can be the cause of malignant VCFs. Although patient clinical history could help raising suspicion for a particular disorder, the characterization of VCFs is usually referred to diagnostic imaging. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Intraosseous hibernoma: clinicopathologic and imaging analysis of 18 cases

AIMS

Intraosseous hibernomas are rarely reported tumours with brown adipocytic differentiation of unknown aetiology, with only 38 cases documented in the literature. We sought to further characterise the clinicopathologic, imaging and molecular features of these tumours.

METHODS AND RESULT

Eighteen cases were identified occurring in eight females and 10 males (median age = 65 years, range = 7-75). Imaging indication was cancer surveillance/staging in 11 patients and clinical concern for a metastasis was raised in 13 patients. The innominate bone (7), sacrum (5), mobile spine (4), humerus (1) and femur (1) were involved. Median tumour size was 1.5 cm (range = 0.8-3.8). Tumours were sclerotic (11), mixed sclerotic and lytic (4) or occult (1). Microscopically, tumours were composed of large polygonal cells with distinct cell membranes, finely vacuolated cytoplasm, central or paracentral small bland nuclei with prominent scalloping. Growth around trabecular bone was observed. Tumour cells were immunoreactive for S100 protein (15/15) and adipophilin (5/5), while negative for keratin AE1/AE3(/PCK26) (0/14) and brachyury (0/2). Chromosomal microarray analysis, performed on four cases, did not show clinically significant copy number variation across the genome or on 11q, the site of AIP and MEN1.

CONCLUSION

Analysis of 18 cases of intraosseous hibernoma, to our knowledge, the largest series to date, revealed that these tumours are most often detected in the spine and pelvis of older adults. Tumours were generally small, sclerotic and frequently found incidentally and can raise concern for metastasis. Whether or not these tumours are related to soft tissue hibernomas is uncertain.

Benign Bone Tumors: State of the Art in Minimally Invasive Percutaneous Interventions

Painful benign bone tumors most commonly affect pediatric patients and young adults. They may be associated with skeletal-related events such as intractable pain, pathologic fracture, neurologic deficit as a consequence of nerve or spinal cord compression, as well as growth disturbance. Consequently, they often result in diminished activity and adversely affect quality of life. There have been substantial recent advances in percutaneous minimally invasive image-guided interventions for treatment of painful benign bone tumors including thermal ablation (radiofrequency ablation, cryoablation, microwave ablation, laser photocoagulation, and high-intensity focused US ablation), chemical (alcohol) ablation, cementoplasty, and intralesional injections. The safety, efficacy, and durability of such interventions have been established in the recent literature and as such, the role of musculoskeletal interventional radiologists in the care of patients with benign bone lesions has substantially expanded. The treatment goal of minimally invasive musculoskeletal interventions in patients with benign bone tumors is to achieve definitive cure. The authors detail the most recent advances and available armamentarium in minimally invasive image-guided percutaneous interventions with curative intent for the management of benign bone tumors. ^© RSNA, 2022.

Dedifferentiated chondrosarcoma with minimal or small dedifferentiated component

Dedifferentiated chondrosarcoma (DDCS) is an aggressive bone sarcoma characterized by low-intermediate grade cartilage component with abrupt transition to a high-grade non-chondrosarcomatous component. Generally, the dedifferentiated (DD) component is large. However, rare cases have minimal (<1 cm) or small (1-2 cm) areas of DD. We describe the clinicopathologic features of such tumors and evaluate the prognostic significance of this finding compared to cases with large DD (>2 cm). Available slides were re-reviewed for assessment of histologic features. The medical record was reviewed for imaging studies and clinical characteristics. Thirty-five cases were included. Six patients had minimal DD, four had small DD and 25 had large DD. None of the minimal DD showed definitive imaging evidence of DD. Two minimal DD (33%) locally recurred and 2 (33%) developed distant metastases. None of the small DD cases showed definitive imaging evidence of DD. None of the small DD locally recurred and at least 1 (25%) developed distant metastases. There was no significant difference in age, gender, pelvic site, tumor size >8 cm, tumor necrosis or undifferentiated pleomorphic sarcoma-like morphology between minimal or small DD compared to large DD, though osteosarcomatous differentiation was significantly more common in large DD. There was no significant difference in overall survival between minimal or small DD compared to large DD (p = 0.81 and p = 0.17, respectively), or in progression-free survival (p = 0.47 and 0.29, respectively), or metastasis-free survival (p = 0.06 and 0.62, respectively). DDCS with minimal or small DD show similar demographic distribution, anatomic localization and histologic features to large DD. DD in these cases is unlikely to be detected on imaging. Furthermore, at least a subset of these tumors is extremely aggressive despite the limited extent of DD. This highlights the need for thorough gross and histologic examination and sampling.

Attitudes and trends in the use of radiolucent spinal implants: A survey of the North American Spine Society section of spinal oncology

Background

In spinal oncology, titanium implants pose several challenges including artifact on advanced imaging and therapeutic radiation perturbation. To mitigate these effects, there has been increased interest in radiolucent carbon fiber (CF) and CF-reinforced polyetheretherketone (CFR-PEEK) implants as an alternative for spinal reconstruction. This study surveyed the members of the North American Spine Society (NASS) section of Spinal Oncology to query their perspectives regarding the clinical utility, current practice patterns, and recommended future directions of radiolucent spinal implants.

Methods

In February 2021, an anonymous survey was administered to the physicians of the NASS section of Spinal Oncology. Participation in the survey was optional. The survey contained 38 items including demographic questions as well as multiple-choice, yes/no questions, Likert rating scales, and short free-text responses pertaining to the “clinical concept”, “efficacy”, “problems/complications”, “practice pattern”, and “future directions” of radiolucent spinal implants.

Results

Fifteen responses were received (71.4% response rate). Six of the participants (40%) were neurosurgeons, eight (53.3%) were orthopedic surgeons, and one was a spinal radiation oncologist. Overall, there were mixed opinions among the specialists. While several believed that radiolucent spinal implants provide substantial benefits for the detection of disease recurrence and radiation therapy options, others remained less convinced. Ongoing concerns included high costs, low availability, limited cervical and percutaneous options, and suboptimal screw and rod designs. As such, participants estimated that they currently utilize these implants for 27.3% of anterior and 14.7% of all posterior reconstructions after tumor resection.

Conclusion

A survey of the NASS section of Spinal Oncology found a lack of consensus with regards to the imaging and radiation benefits, and several ongoing concerns about currently available options. Therefore, routine utilization of these implants for anterior and posterior spinal reconstructions remains low. Future investigations are warranted to practically validate these devices’ theoretical risks and benefits.

Interventional Palliation of Painful Extraspinal Musculoskeletal Metastases

The musculoskeletal system is commonly involved by metastases, and skeletal-related events such as intractable pain due to direct osseous tumor involvement, pathologic fracture, and neurologic deficits as a result of nerve compression often adversely affect patient's quality of life. There have been substantial advances in percutaneous minimally invasive musculoskeletal oncologic interventions for the management of patients with musculoskeletal metastases including thermal ablations, cementation with or without osseous reinforcement via implants, osteosynthesis, neurolysis, and palliative injections which are progressively incorporated in clinical practice. These interventions are performed, in conjunction with or supplemented by adjuvant radiation therapy, systemic therapy, surgery, or analgesics, to achieve durable pain palliation, local tumor control, or cure. This article reviews minimally invasive percutaneous image-guided musculoskeletal oncologic interventions for the management of patients with extraspinal musculoskeletal metastases.

Percutaneous image-guided cryoablation of spinal metastases: over 10-year experience in two academic centers

OBJECTIVES

To report on safety and clinical effectiveness of cryoablation for the treatment of spinal metastases (SM) in patients needing pain palliation or local tumor control (LTC).

METHODS

All consecutive patients with SM who underwent cryoablation from May 2008 to September 2020 in two academic centers were retrospectively identified and included in the present analysis. Patient characteristics, goal of treatment (curative/palliative), SM characteristics, procedural details, and clinical outcomes (pain relief; local tumor control [LTC]) were analyzed.

RESULTS

There were 74 patients (35 women; median age 61 years) accounting for 105 SM. Additional cementoplasty was used for 76 SM (76/105; 72.4%). There were 9 complications (out of 105 SM [8.5%]; 2 major and 7 minor) in 8 patients. Among the 64 (64/74; 86.5%) patients with painful SM, the mean Numerical Pain Rating Scale dropped from 6.8 ± 2.2 (range, 0-10) at the baseline to 4.1 ± 2.4 (range, 0-9; p < 0.0001) at 24 h, 2.5 ± 2.6 (range, 0-9; p < 0.0001) at 1 month, and 2.4 ± 2.5 (range, 0-9; p < 0.0001) at the last available follow-up (mean 14.7 ± 19.6 months; median 6). Thirty-four patients (34/64; 53.1%) were completely pain-free at the last follow-up. At mean 25.9 ± 21.2 months (median 16.5) of follow-up, LTC was achieved in 23/28 (82.1%) SM in 21 patients undergoing cryoablation with curative intent.

CONCLUSION

Cryoablation of SM, often performed in combination with vertebral augmentation, is safe, achieves fast and sustained pain relief, and provides high rates of LTC at mean 2-year follow-up.

KEY POINTS

•Cryoablation of spinal metastases is safe. •Cryoablation of spinal metastases allows rapid and sustained pain relief. •The mean 2-year rate of local tumor control after cryoablation of spinal metastases is 82.1%.

Bone marrow aspiration and biopsy: techniques and practice implications

Bone marrow aspiration and biopsy (BMAB) is a valuable diagnostic procedure commonly performed for evaluation of a wide spectrum of diseases including hematologic abnormalities, nonhematologic malignancies, metabolic abnormalities, and tumor treatment response such as chemotherapy and bone marrow transplantation, hematologic tumor staging, and suspected infection in patients with fever of unknown origin. This minimally invasive intervention offers excellent safety profile and a high diagnostic yield. Radiologists should be familiar with clinical implications of BMAB for patient care and be able to implement various technical armamentarium available to achieve a safe intervention while maximizing procedure yield.

Bone Metastases: State of the Art in Minimally Invasive Interventional Oncology

Bone is the third most common site involved by cancer metastases, and skeleton-related events such as intractable pain due to direct osseous tumor involvement, pathologic fracture, and neurologic deficits as a consequence of nerve or spinal cord compression often affect patients' functional independence and quality of life unfavorably. The annual medical-economic burden related to bone metastases is a substantial component of the total direct medical cost estimated by the National Institutes of Health. There have been substantial recent advances in percutaneous image-guided minimally invasive musculoskeletal oncologic interventions for the management of patients with osseous metastatic disease. These advances include thermal ablation, cementation with or without osseous reinforcement with implants, osteosynthesis, thermal and chemical neurolyses, and palliative injections, which are progressively incorporated into the management paradigm for such patients. These interventions are performed in conjunction with or are supplemented by adjuvant radiation therapy, systemic therapy, surgery, or analgesic agents to achieve durable pain palliation, local tumor control, or cure, and they provide a robust armamentarium for interventional radiologists to achieve safe and effective treatment in a multidisciplinary setting. In addition, these procedures are shifting the patient management paradigm in modern-era practice. The authors detail the state of the art in minimally invasive percutaneous image-guided musculoskeletal oncologic interventions and the role of radiologists in managing patients with skeletal metastases. ^©RSNA, 2021.

First in-human report of the clinical accuracy of thoracolumbar percutaneous pedicle screw placement using augmented reality guidance

OBJECTIVE

Augmented reality (AR) is an emerging technology that has great potential for guiding the safe and accurate placement of spinal hardware, including percutaneous pedicle screws. The goal of this study was to assess the accuracy of 63 percutaneous pedicle screws placed at a single institution using an AR head-mounted display (ARHMD) system.

METHODS

Retrospective analyses were performed for 9 patients who underwent thoracic and/or lumbar percutaneous pedicle screw placement guided by ARHMD technology. Clinical accuracy was assessed via the Gertzbein-Robbins scale by the authors and by an independent musculoskeletal radiologist. Thoracic pedicle subanalysis was also performed to assess screw accuracy based on pedicle morphology.

RESULTS

Nine patients received thoracic or lumbar AR-guided percutaneous pedicle screws. The mean age at the time of surgery was 71.9 ± 11.5 years and the mean number of screws per patient was 7. Indications for surgery were spinal tumors (n = 4, 44.4%), degenerative disease (n = 3, 33.3%), spinal deformity (n = 1, 11.1%), and a combination of deformity and infection (n = 1, 11.1%). Presenting symptoms were most commonly low-back pain (n = 7, 77.8%) and lower-extremity weakness (n = 5, 55.6%), followed by radicular lower-extremity pain, loss of lower-extremity sensation, or incontinence/urinary retention (n = 3 each, 33.3%). In all, 63 screws were placed (32 thoracic, 31 lumbar). The accuracy for these screws was 100% overall; all screws were Gertzbein-Robbins grade A or B (96.8% grade A, 3.2% grade B). This accuracy was achieved in the thoracic spine regardless of pedicle cancellous bone morphology.

CONCLUSIONS

AR-guided surgery demonstrated a 100% accuracy rate for the insertion of 63 percutaneous pedicle screws in 9 patients (100% rate of Gertzbein-Robbins grade A or B screw placement). Using an ARHMS system for the placement of percutaneous pedicle screws showed promise, but further validation using a larger cohort of patients across multiple surgeons and institutions will help to determine the true accuracy enabled by this technology.

Musculoskeletal Oncologic Interventions: Proceedings from the Society of Interventional Radiology and Society of Interventional Oncology Research Consensus Panel

Musculoskeletal interventions are increasingly used with palliative and curative intent in the multidisciplinary treatment of oncology patients with bone and soft-tissue tumors. There is an unmet need for high-quality evidence to guide broader application and adoption of minimally invasive interventional technologies to treat these patients. Therefore, the Society of Interventional Radiology Foundation and the Society of Interventional Oncology collaborated to convene a research consensus panel to prioritize a research agenda addressing the gaps in the current evidence. This article summarizes the panel's proceedings and recommendations for future basic science and clinical investigation to chart the course for interventional oncology within the musculoskeletal system. Key questions that emerged addressed the effectiveness of ablation within specific patient populations, the effect of combination of ablation with radiotherapy and/or immunotherapy, and the potential of standardization of techniques, including modeling and monitoring, to improve the consistency and predictability of treatment outcomes.

Safety of bone marrow aspiration and biopsy in severely thrombocytopenic patients

PURPOSE

To assess the safety of fluoroscopically guided drill-assisted bone marrow aspirate and biopsy in severely thrombocytopenic patients.

MATERIALS AND METHODS

The study was approved by the IRB with waiver of informed consent. Retrospective review of 111 bone marrow aspirate and biopsies (BMAB) performed in 94 patients who received a CT scan which included the pelvis and biopsy site within the 7 days following the BMAB. The 94 patients were subdivided based on their platelet count: severe thrombocytopenia (< 20 platelets × 10⁹/L), thrombocytopenia (20-50 platelets × 10⁹/L), and control (> 50 platelets × 10⁹/L). The procedure report was reviewed for sedation time, aspirate volume, and aggregate size of core biopsy specimens. The electronic medical record was reviewed for specimen adequacy; pathologic diagnosis; body mass index; pre- and post-procedure labs including platelet count, hemoglobin (HGB), hematocrit (HCT), prothrombin time (PT), and international normalized ratio (INR) levels; post-procedural transfusion; and complications including mortality at 30 and 90 days. CT scans were independently reviewed by 2 fellowship-trained radiologists for the presence of post-procedural hemorrhage.

RESULTS

There was no significant difference in CT-identified post-procedural hematoma, or change in the hemoglobin and hematocrit levels pre- and post-procedure between the three groups. There was no significant difference in complication rate or all-cause mortality. There was a significant difference in transfusion at 30 days with thrombocytopenic and severely thrombocytopenic patients more likely to receive transfusion within the 30 days post-procedure.

CONCLUSION

Fluoroscopically guided BMAB can be safely performed in patients with severe thrombocytopenia.

Vertebral augmentation reduces the 12-month mortality and morbidity in patients with osteoporotic vertebral compression fractures

OBJECTIVES

To investigate the 12-month all-cause mortality and morbidity in patients with osteoporotic vertebral compression fractures (OVCFs) undergoing vertebroplasty/balloon kyphoplasty (VP/BKP) versus non-surgical management (NSM).

METHODS

Following a Medline and EMBASE search for English language articles published from 2010 to 2019, 19 studies reporting on mortality and morbidity after VP/BKP in patients with OVCFs were selected. The 12-month timeline was set due to the largest amount of data availability at such time interval. Estimates for each study were reported as odds ratios (OR) along with 95% confidence intervals (CI) and p values. Fixed or random-effects meta-analyses were performed. All tests were based on a two-sided significance level of 0.05.

RESULTS

Pooled OR across 5 studies favored VP/BKP over NSM in terms of 12-month all-cause mortality (OR: 0.81 [95% CI: 0.46-1.42]; p = .46). Pooled OR across 11 studies favored VP/BKP over NSM in terms of 12-month all-cause morbidity (OR: 0.64 [95% CI: 0.31-1.30]; p = .25). Sub-analysis of data dealing with 12-month infective morbidity from any origin confirmed the benefit of VP/BKP over NSM (OR: 0.23 [95% CI, 0.02-2.54]; p = .23).

CONCLUSION

Compared to NSM, VP/BKP reduces the 12-month risk of all-cause mortality and morbidity by 19% and 36%, respectively. Moreover, VP/BKP reduces by 77% the 12-month risk of infection from any origin.

KEY POINTS

• Compared to non-surgical management, vertebral augmentation reduces the 12-month risk of all-cause mortality by 19% and all-cause morbidity by 36%. • Vertebral augmentation reduces the 12-month risk of infection morbidity from any origin by 77%.

Cryoablation for Palliation of Painful Bone Metastases: The MOTION Multicenter Study

PURPOSE

To assess the clinical effectiveness of cryoablation for palliation of painful bone metastases.

MATERIALS AND METHODS

MOTION (Multicenter Study of Cryoablation for Palliation of Painful Bone Metastases) (ClinicalTrials.gov NCT02511678) was a multicenter, prospective, single-arm study of adults with metastatic bone disease who were not candidates for or had not benefited from standard therapy, that took place from February 2016 to March 2018. At baseline, participants rated their pain using the Brief Pain Inventory-Short Form (reference range from 0 to 10 points); those with moderate to severe pain, who had at least one metastatic candidate tumor for ablation, were included. The primary effectiveness endpoint was change in pain score from baseline to week 8. Participants were followed for 24 weeks after treatment. Statistical analyses included descriptive statistics and logistic regression to evaluate changes in pain score over the postprocedure follow-up period.

RESULTS

A total of 66 participants (mean age, 60.8 years ± 14.3 [standard deviation]; 35 [53.0%] men) were enrolled and received cryoablation; 65 completed follow-up. Mean change in pain score from baseline to week 8 was -2.61 points (95% CI: -3.45, -1.78). Mean pain scores improved by 2 points at week 1 and reached clinically meaningful levels (more than a 2-point decrease) after week 8; scores continued to improve throughout follow-up. Quality of life improved, opioid doses were stabilized, and functional status was maintained over 6 months. Serious adverse events occurred in three participants.

CONCLUSION

Cryoablation of metastatic bone tumors provided rapid and durable pain palliation, improved quality of life, and offered an alternative to opioids for pain control.Keywords: Ablation Techniques, Metastases, Pain Management, Radiation Therapy/OncologySupplemental material is available for this article.© RSNA, 2021.

Fluoroscopy-guided bone marrow aspiration and biopsy: technical note

Bone marrow aspiration and biopsy is a valuable procedure commonly utilized for evaluation of hematologic abnormalities, nonhematologic malignancies, metabolic abnormalities, tumor treatment response, and suspected infection in patients with fever of unknown origin. Imaging guidance with computed tomography (CT) is commonly utilized to improve safety and effectiveness of the procedure. Considering progressively increasing volume of complex CT-guided procedures as well as diagnostic CT imaging in most practices potentially resulting in limited availability of CT, a technique for fluoroscopy-guided bone marrow aspiration and biopsy is described with focus on advantages, which could be beneficial to most busy practices in modern era radiology.

Percutaneous thermal ablation alone or in combination with cementoplasty for renal cell carcinoma osseous metastases: Pain palliation and local tumour control

INTRODUCTION

To evaluate the safety and efficacy of minimally invasive percutaneous thermal ablation alone or in combination with cementoplasty for pain palliation and local tumour control of renal cell carcinoma osseous metastases.

METHODS

Imaging-guided thermal ablation was performed in 59 renal cell carcinoma osseous metastatic tumours in 23 patients (concomitant cementoplasty in 43 tumours) selected following multidisciplinary consultations to achieve local tumour control and pain palliation (75%, 44/59) or pain palliation alone (25%, 15/59) in this retrospective study. Tumour characteristics, procedural details and complications were documented. Pain palliation was assessed using pre- and post-procedural Numeric Rating Scale scores at 1-week, 1-month, 3-month and 6-month time intervals. Pre- and post-procedural cross-sectional imaging was reviewed to assess local tumour control rates at 3-month, 6-month, and 12-month post-treatment time intervals.

RESULTS

All procedures were technically successful and performed as pre-operatively planned. The median pre- and post-procedural Numeric Rating Scale scores were 8.0 and 3.0 (at all time intervals), respectively (P < 0.001). Local tumour control rates were 100% (40/40), 100% (36/36) and 85% (28/33) at ≥3 months, ≥6 months and ≥12 months post-procedural time intervals, respectively. There was 1 minor complication (1.7%, 1/59).

CONCLUSIONS

Percutaneous thermal ablation alone or in combination with cementoplasty is safe and effective for pain palliation and local tumour control of renal cell carcinoma osseous metastases.

Three-Column Classification System for Tibial Plateau Fractures: What the Orthopedic Surgeon Wants to Know

Recent orthopedic surgical literature emphasizes a three-column approach to understand and guide the treatment of tibial plateau fractures. This three-column classification system published in 2010 relies on preoperative CT images to depict injuries to the medial, lateral, and posterior columns of the tibial plateau and improves surgical outcomes in complex tibial plateau fractures with coronal fracture planes and posterior plateau fracture fragments requiring dorsal plating. Tibial plateau fracture classification systems traditionally used by radiologists and orthopedic surgeons, including the Schatzker and the Arbeitsgemeinschaft für Osteosynthesefragen-Orthopedic Trauma Association (AO-OTA) classification systems, rely on findings at anteroposterior radiography and lack the terminology to accurately characterize fractures in the coronal plane involving the posterior tibial plateau. Incorporating elements from the contemporary three-column classification system into radiology reports will enhance radiologists' descriptions of these injuries. It is essential for radiologists to understand the role of clinical assessment and the pertinent imaging findings taken into consideration by orthopedic surgeons in their management of these injuries. This understanding includes familiarity with injury patterns and how they relate to mechanism of injury, patient demographics, and underlying pertinent comorbidities. Evaluating findings on initial radiographs is the basis of tibial plateau fracture diagnosis. Additional information provided by preoperative cross-sectional imaging, including two-dimensional and three-dimensional CT and MRI in specific circumstances, aids in the identification of specific soft-tissue injuries and fracture morphologies that influence surgical management. These specific fracture morphologies and soft-tissue injuries should be identified and communicated to orthopedic surgeons for optimal patient management. Online DICOM image stacks are available for this article. ^©RSNA, 2020.

Spine-specific skeletal related events and mortality in non-small cell lung cancer patients: a single-institution analysis

OBJECTIVE

The population prevalence of non-small cell lung cancer (NSCLC) continues to increase; however, data are limited regarding the incidence rate of skeletal related events (SREs) (i.e., surgery to the spinal column, radiation to the spinal column, radiofrequency ablation, kyphoplasty/vertebroplasty, spinal cord compression, or pathological vertebral body fractures) and their impact on overall mortality. In this study, the authors sought to estimate the incidence rates of SREs in NSCLC patients and to quantify their impact on overall mortality.

METHODS

This was a single-institution retrospective study of patients diagnosed with NSCLC between 2002 and 2014. The incidence rates for bone metastasis and subsequent SREs (per 1000 person-years) by time since lung cancer diagnosis were calculated and analyses were stratified separately for each histological type. Incidence rates for mortality at 1, 2, and 3 years from diagnosis stratified by the presence of SREs were also calculated. Kaplan-Meier survival curves were constructed to describe crude survival ratios in patients with spine metastasis and SREs and those with spine metastasis but without SREs. These curves were used to estimate the 1- and 2-year survival rates for each cohort.

RESULTS

We identified 320 patients with incident NSCLC (median follow-up 9.5 months). The mean ± SD age was 60.65 ± 11.26 years; 94.48% of patients were smokers and 60.12% had a family history of cancer. The majority of first-time SREs were pathological vertebral body compression fractures (77.00%), followed by radiation (35%), surgery (14%), and spinal cord compression (13.04%). Mortality rates were highest in NSCLC patients with spine metastasis who had at least 1 SRE. Stratifying by histological subtype, the incidence rate of mortality in patients with SRE was highest in the large cell cohort, 7.42 per 1000 person-years (95% CI 3.09-17.84 per 1000 person-years); followed by the squamous cell cohort, 2.49 per 1000 person-years (95% CI 1.87-3.32 per 1000 person-years); and lowest in the adenocarcinoma cohort, 1.68 per 1000 person-years (95% CI 1.46-1.94 per 1000 person-years). Surgery for decompression of neural structures and stabilization of the spinal column was required in 6% of patients.

CONCLUSIONS

SREs in NSCLC patients with bone metastasis are associated with an increased incidence rate of mortality.

Unifocal Langerhans cell histiocytosis of bone: percutaneous navigational bipolar radiofrequency ablation for curative treatment

In this report, the initial clinical experience of authors is described on the novel application of a navigational bipolar radiofrequency ablation electrode system for curative treatment of a painful unifocal Langerhans cell histiocytosis involving the supra-acetabular iliac bone. The technical success and safety of the radiofrequency ablation procedure to achieve cure suggests that this intervention may be utilized in clinical practice as a viable and minimally invasive alternative option, for management of unifocal Langerhans cell histiocytosis.

Vertebral Metastases: Minimally Invasive Percutaneous Thermal Ablation

This article provides a step-by-step guide for minimally invasive percutaneous image-guided thermal ablation for treatment of vertebral metastases. Such interventions have proved safe and effective in management of selected patients with spinal metastases primarily to achieve pain palliation and local tumor control. Particular attention to patient selection guidelines, details of procedure techniques, thermal protection, adequacy of treatment, recognition and management of potential complications, and post-ablation imaging are essential for improved patient outcomes.

Evaluation of the Metastatic Spine Disease Multidisciplinary Working Group Algorithms as Part of a Multidisciplinary Spine Tumor Conference

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The Metastatic Spine Disease Multidisciplinary Working Group Algorithms are evidence and expert opinion-based strategies for utilizing radiation therapy, interventional radiology procedures, and surgery to treat 5 types of spine metastases: asymptomatic spinal metastases, uncomplicated spinal metastases, stable vertebral compression fractures (VCF), unstable VCF, and metastatic epidural spinal cord compression (MESCC). Evaluation of this set of algorithms in a clinical setting is lacking. The authors aimed to identify rate of treatment adherence to the Working Group Algorithms and, subsequently, update these algorithms based on actual patient management decisions made at a single-institution, multidisciplinary, spine tumor conference.

METHODS

Patients with metastatic spine disease from primary non-hematologic malignancies discussed at an institutional spine tumor conference from 2013 to 2016 were evaluated. Rates of Working Group Algorithms adherence were calculated for each type of metastasis. Based on the reasons for algorithm nonadherence, and patient outcomes in such cases, updated Working Group Algorithms recommendations were proposed.

RESULTS

In total, 154 eligible patients with 171 spine metastases were evaluated. Rates of algorithm adherence were as follows: asymptomatic (67%), uncomplicated (73%), stable VCF (20%), unstable VCF (32%), and MESCC (41%). The most common deviation from the Working Group Algorithms was surgery for MESCC despite poor prognostic factors, but this treatment strategy was supported based on median survival surpassing 6 months in these patients.

CONCLUSIONS

Adherence to the Working Group Algorithm was lowest for MESCC and VCF patients, but many nonadherent treatments were supported by patient survival outcomes. We proposed updates to the Working Group Algorithm based on these findings.

Percutaneous CT-Guided Core Needle Biopsies of Head and Neck Masses: Technique, Histopathologic Yield, and Safety at a Single Academic Institution

BACKGROUND AND PURPOSE

CT-guided head and neck biopsies can be challenging due to the anatomy and adjacent critical structures but can often obviate the need for open biopsy. A few studies and review articles have described approaches to biopsy in the head and neck. This retrospective study evaluated technical considerations, histopathologic yield, and safety in CT-guided head and neck core needle biopsies.

MATERIALS AND METHODS

A retrospective review of head and neck biopsies performed from January 2013 through December 2019 was conducted. Clinical diagnosis and indication, patient demographics, mass location and size, biopsy needle type, technical approach, dose-length product, sedation details, complications, diagnostic histopathologic yield, and the use of iodinated contrast were recorded for each case.

RESULTS

A total of 27 CT-guided head and neck core needle biopsies were performed in 26 patients. The diagnostic sample rate was 100% (27/27). A concordant histopathologic diagnosis was obtained in 93% (25/27) of cases. There was a single complication of core needle biopsy, a small asymptomatic superficial hematoma.

CONCLUSIONS

Percutaneous CT-guided biopsy of deep masses in the head and neck is safe and effective with careful biopsy planning and has a high diagnostic yield that can obviate the need for open biopsy.

Digital Subtraction Air Arthrography: An Innovative Technique for Needle Tip Location Confirmation

PURPOSE

This article describes an innovative technique to confirm needle tip positioning using digital subtraction fluoroscopy and air within a targeted joint.

MATERIALS AND METHODS

Digital subtraction fluoroscopy with air was utilized to confirm intra-articular needle tip position in 12 joints over a 14-month period at a single institution. Procedural details were recorded for each joint including: joint location, fluoroscopy time, patient age, patient body mass index, and change in subjective pain rating following the injection. Shoulder and hip phantoms were utilized to compare radiation dose differences between fluoroscopy with digital subtraction technique and fluoroscopy without digital subtraction technique.

RESULTS

All of the 12 injections were technically successful with air clearly visualized within each targeted joint and subjective pain ratings either did not change or decreased following the injection. Patient age ranged from 51 to 87 years old and body mass index values ranged from 19.2 to 37.1 kg/m². Fluoroscopy times ranged from 11.1 to 32.9 seconds. There were no complications during or immediately following the injections. The addition of digital subtraction technique increased the skin dose at the shoulder by approximately 2.6 times and at the hip by approximately 2.2 times. Likewise, the cumulative dose at the shoulder increased by approximately 2.7 times and at the hip by 2.0 times.

CONCLUSION

Fluoroscopic digital subtraction air arthrography is a valuable option for needle tip confirmation when using air as a contrast agent. This novel combination of established fluoroscopic techniques can be incorporated into most clinical practices.

Efficacy and safety of bone marrow aspiration and biopsy using fluoroscopic guidance and a drill-powered needle: clinical experience from 775 cases

OBJECTIVES

To evaluate the efficacy and safety of performing a fluoroscopically guided bone marrow aspiration and biopsy (BMAB) using a drill-powered needle in a large patient population.

METHODS

This retrospective study received institutional review board approval with a waiver of patient informed consent. We identified all BMAB procedures from August 2012 through December 2016 performed at our institution using fluoroscopic guidance and a drill-powered needle. Clinical diagnosis, patient age, patient gender, biopsy site, biopsy needle gauge, bone marrow aspirate volume, bone marrow core biopsy length, patient platelet count, conscious sedation details, complications, and diagnostic adequacy were investigated for each case and summarized.

RESULTS

A total of 775 BMAB procedures were performed and analyzed. These were performed in 436 female patients and 339 male patients ranging in age between 16 and 91 years (average age of 53 years). Samples obtained from the procedures in our series were diagnostic in 95.0% of cases. The complication rate for our series was 0.3%.

CONCLUSIONS

The use of fluoroscopic guidance and a drill-powered needle for bone marrow aspiration and biopsy is a safe and efficacious procedure.

KEY POINTS

• Fluoroscopy can be utilized for imaging guidance during bone marrow aspiration and biopsy. • The use of fluoroscopic guidance and a drill-powered needle for bone marrow aspiration and biopsy has a high diagnostic yield. • The procedure has an excellent patient safety profile.

Percutaneous Interventional Techniques for Treatment of Spinal Metastases

This article details an approach for evaluation as well as minimally invasive percutaneous treatment of spinal metastases focusing on thermal ablation and most recent advances. Safe and effective management of certain subgroups of patients with spinal metastases can be achieved by minimally invasive percutaneous thermal ablation with or without vertebral augmentation. Adjunctive palliative treatment options such as epidural or neuroforaminal corticosteroid and long-acting anesthetic injections may also be performed in patients who have nerve and radicular pain including those who are not candidates for thermal ablation. Thermal protection strategies should be implemented to minimize the risk of neural thermal injury.

Primary osseous sacral neuroblastoma in an adult

Neoplasms of the sacrum are rare. Given the non-specific imaging findings in sacral lesions, the imaging-based differential diagnosis is always difficult. This case is about an adult with primary sacral neuroblastoma and we have discussed imaging and histopathological findings of this rare tumor.

Percutaneous CT-Guided Skull Biopsy: Feasibility, Safety, and Diagnostic Yield

BACKGROUND AND PURPOSE

Although percutaneous musculoskeletal biopsies are routinely performed in the axial and appendicular skeleton, there are no published data on the systematic evaluation of the feasibility, safety, and diagnostic accuracy of percutaneous skull biopsy. In certain clinical encounters such as patients with primary skull tumors or patients with known cancer and isolated skull lesions suspected of calvarial metastasis or synchronous primary tumor, percutaneous skull biopsy may be considered a viable option. The purpose of this study was to evaluate the feasibility, safety profile, and diagnostic yield of percutaneous CT-guided skull biopsy.

MATERIALS AND METHODS

Percutaneous CT-guided skull biopsy was performed in 14 patients. Patient demographics, cancer history, indication for initial imaging, imaging technique of diagnosis, skull tumor anatomic location, and final histologic diagnosis were documented. Preprocedural imaging of each skull lesion was reviewed to determine tumor size and characteristics. Procedural notes were reviewed to determine the total conscious sedation time or anesthesia time, type of biopsy needle, and the number and length of obtained core specimens. Procedure-related complications were also documented according to the Society of Interventional Radiology classification.

RESULTS

All CT-guided percutaneous skull biopsy procedures were performed as preoperatively planned and were technically successful. Procedures were performed with the patient under conscious sedation in 93% (13/14) of cases. Definitive histologic diagnosis was achieved in 86% (12/14) of cases. There were no acute or delayed procedure-related complications.

CONCLUSIONS

The results of this retrospective initial study suggest that percutaneous CT-guided skull biopsy is feasible with an excellent safety profile, affords a high diagnostic yield for histologic characterization, and may obviate more invasive open skull biopsies.

Percutaneous Radiofrequency Ablation of Spinal Osteoid Osteomas Using a Targeted Navigational Bipolar Electrode System

Safe and effective percutaneous CT-guided radiofrequency ablation of spinal osteoid osteomas can be performed using a targeted navigational bipolar electrode system. Articulating bipolar electrodes with built-in thermocouples along an electrode shaft and variable generator wattage settings allow optimal nidus access, particularly in challenging locations; provide precise real-time monitoring of ablation zone volume and geometry; and minimize the risk of undesired thermal injury.