Ultrasound-guided transforaminal approach for nusinersen delivery in adult spinal muscle atrophy patients with challenging access.

INTRODUCTION/AIMS: Previous papers on ultrasound (US)-guided delivery of nusinersen in patients with spinal muscle atrophy (SMA) described good results with translaminar approach. However, this approach is not possible in patients with spinal fusion and no visible interlaminar space on pre-procedural computed tomography (CT). US-guided transforaminal nusinersen delivery is a potential option that warrants investigation. METHODS: Twenty adult SMA patients with challenging access were treated in our institution under cone beam CT (CBCT) guidance. The patients were already in the maintenance phase of the dosing protocol and were prospectively evaluated for US-guided transforaminal approach. After they completed one injection via US-guided transforaminal approach, success and safety of the approach were analyzed. Patients shared their experience on US-guided in comparison to CBCT-guided injections. RESULTS: US-guided transforaminal puncture was possible in 14 (70.0%) patients, although 2 of them required needle repositioning under fluoroscopy due to inadvertent access of a prominent vein. US-guided transforaminal approach was therefore successful in 60% of patients. Mild adverse events were recorded in four patients. The survey on patients' experience showed that seven reported no difference in the two approaches, six preferred the US-guided procedure, and one preferred the CBCT-guided procedure. DISCUSSION: US-guided transforaminal lumbar approach is an effective and safe method of intrathecal nusinersen delivery in adult SMA patients with challenging spinal access and could be considered the first option in appropriately selected adult SMA patients requiring transforaminal nusinersen delivery.

Detection and evaluation of haemophilic arthropathy: Which tools may be considered more reliable.

INTRODUCTION: Progressive arthropathy is the main cause of morbidity in patients with severe haemophilia. Diagnostic imaging can detect even subclinical arthropathy and impact prophylactic treatment. However, in most clinical settings the regular joint evaluation and follow-up are based on clinical evaluation and patient's personal reporting of problems, while diagnostic imaging is not regularly employed. AIM: The aim of our prospective study was to assess how ultrasound (US), clinical examination, patient's subjective assessment and certain laboratory biomarkers correlate with magnetic resonance imaging (MRI) for detection and evaluation of haemophilic arthropathy in order to determine which tool is the most reliable. METHODS: The study included 30 patients with severe haemophilia (age range 16-49 years). MRI (IPSG), US (HEAD-US), clinical examination (HJHS 2.1) and patient's subjective assessment of elbows, knees and ankles were performed; additionally, blood samples for laboratory analysis were taken (s-25-OH vitamin D, s-ferritin, s-C-terminal telopeptide of type I collagen, s-N-terminal propeptide of type I procollagen and s-cartilage oligomeric matrix protein). MRI results were used as a reference standard for joint status. Pearson's r was used to assess correlation of other methods with MRI. RESULTS: The correlation with MRI was the highest for US (r = .92), considerably higher than for clinical evaluation (r = .62) and patient's subjective assessment (r = .66). There was no correlation between the presence or degree of haemophilic arthropathy and any of the laboratory biomarkers. CONCLUSION: The results of our study warrant the inclusion of US into the regular follow-up of patients with severe haemophilia, where the equipment and staffing permit.

Novel ASAP1-USP6, FAT1-USP6, SAR1A-USP6, and TNC-USP6 fusions in primary aneurysmal bone cyst.

Aneurysmal bone cyst (ABC) is a benign but locally aggressive neoplasm, with a tendency for local recurrence. In contrast to other bone tumors with secondary cystic change, ABC is characterized by USP6 gene rearrangement. There is a growing list of known USP6 fusion partners, characterization of which has been enabled with the advent of next-generation sequencing (NGS). The list of known fusion partners includes CDH11, CNBP, COL1A1, CTNNB1, EIF1, FOSL2, OMD, PAFAH1B1, RUNX2, SEC31A, SPARC, STAT3, THRAP3, and USP9X. Using NGS, we analyzed a series of 11 consecutive ABCs and identified USP6 fusions in all cases, providing further evidence that USP6 fusions are universally present in primary ABCs. We identified four novel fusion partners in five ABCs and confirmed them by RT-PCR and Sanger sequencing, ASAP1, FAT1, SAR1A, and TNC (in two cases). Because of high sensitivity and specificity, detection of a USP6 fusion by NGS may assist in differentiating between ABC and its mimics, especially in small biopsy samples when a definite diagnosis cannot be achieved on morphological grounds alone. Further studies with a large number of cases and follow-up are needed to determine whether different fusion partners are associated with specific clinical and pathologic features of ABCs.

Present Status of Musculoskeletal Radiology in Europe: International Survey by the European Society of Musculoskeletal Radiology.

No official data exist on the status of musculoskeletal (MSK) radiology in Europe. The Committee for National Societies conducted an international survey to understand the status of training, subspecialization, and local practice among the European Society of Musculoskeletal Radiology (ESSR) partner societies. This article reports the results of that survey. An online questionnaire was distributed to all 26 European national associations that act as official partner societies of the ESSR. The 24 questions were subdivided into six sections: society structure, relationship with the national radiological society, subspecialization, present radiology practice, MSK interventional procedures, and MSK ultrasound. The findings of our study show a lack of standardized training and/or accreditation methods in the field of MSK radiology at a national level. The European diploma in musculoskeletal radiology is directed to partly overcome this problem; however, this certification is still underrecognized. Using certification methods, a more homogeneous European landscape could be created in the future with a view to subspecialist training. MSK ultrasound and MSK interventional procedures should be performed by a health professional with a solid knowledge of the relevant imaging modalities and sufficient training in MSK radiology. Recognition of MSK radiology as an official subspecialty would make the field more attractive for younger colleagues as well as attracting the brightest and best, an important key to further development of both clinical and academic radiology. KEY POINTS: · Standardized training and/or accreditation methods in the field of MSK radiology is lacking at a national level.. · With certification methods, such as the European diploma in musculoskeletal radiology, a more homogeneous European landscape could be created in the future with a view to subspecialist training.. · Recognition of MSK radiology as an official subspecialty would make the field more attractive for younger colleagues as well as attracting the brightest and best, an important key to further development of both clinical and academic radiology..

A descriptive study of potential effect of anterior tibial translation, femoral tunnel and anterior cruciate ligament graft inclination on clinical outcome and degenerative changes.

INTRODUCTION: There is no evidence that anatomically correct anterior cruciate ligament reconstruction (ACLR) offers lower rate of degenerative changes development or that it would lead to a better outcome. The significance and understanding of the abnormal anterior tibial translation (ATT) in ACLR patients is yet to be established. METHODS: Sixty subjects (40 patients at 5.9 years after ACLR, 20 healthy controls) underwent 3 T MRI. Quantitative cartilage T2 mapping and morphological whole organ magnetic resonance imaging score (WORMS) evaluation was performed. Self-reported questionnaires were used for subjective clinical evaluation. Correlations were calculated with the following MRI measurements; femoral tunnel inclination, ACL graft inclination, lateral and medial compartment ATT. RESULTS: In the ACLR group positive correlation was found between the patellar cartilage T2 values and sagittal ACL graft inclination. In the ACLR group lateral compartment ATT showed negative correlation with ACL graft inclination and subjective clinical evaluation, and positive correlation with morphological degenerative changes. Femoral tunnel showed positive correlation with ACL graft inclination in the same plane. CONCLUSIONS: Increased ATT offers worse clinical outcome and increased rate of degenerative changes. Furthermore, ATT is affected by the ACL inclination. Inclination of the drilling tunnel affects ACL graft inclination; thereby independent drilling techniques provide superior results of anatomical ACL graft positioning.

Retrospective quantitative cartilage and semi-quantitative morphological evaluation at 6 years after ACL reconstruction.

UNLABELLED: Purpose We analyzed anterior cruciate ligament reconstruction (ACLR) patients in order to evaluate degenerative changes and the effect of meniscal insufficiency at mid-term follow-up. METHODS: Sixty subjects (40 patients at 5.9 years after ACLR, 20 healthy controls) underwent 3T MRI. Quantitative cartilage T2 mapping and morphological Whole Organ Magnetic Resonance Imaging Score (WORMS) evaluation were performed. Self-reported questionnaires were used for subjective clinical evaluation. Based on the meniscal status at ACLR, further subdivision within each compartment (lateral and medial) was made: menisci intact and menisci insufficient. RESULTS: The ACLR subjects showed significantly elevated T2 values and higher WORMS scores compared to the control group. T2 values of the anterior lateral femoral subcompartment were significantly higher in menisci insufficient group compared to the control group. In both compartments significantly higher WORMS scores were observed in the menisci insufficient group compared to the menisci intact group. CONCLUSIONS: ACLR knees exhibit cartilage matrix and morphological degeneration at mid-term follow-up. Lateral meniscal insufficiency noted at ACLR presents a higher risk of developing degenerative changes than does the medial meniscus insufficiency; however, this difference may not be detected clinically.

Haemostasis for 568 large femoral artery access sites - outcomes and predictors of success.

BACKGROUND: The introduction of stent grafts for thoracic and abdominal aorta (T / EVAR) has raised the demand for percutaneous closure devices for larger femoral arterial access sites. The aim of our study was to evaluate the success and complication rate of completely percutaneous T / EVAR with Prostar XL® and surgical haemostasis over a 50- month period. PATIENTS AND METHODS: Between December 16th 2005 and February 17th 2010 T / EVAR was performed in 306 patients with 568 arterial access sites with diameters of 12 to 24 Fr. The exclusion criteria for percutaneous haemostasis were a calcified anterior wall at the puncture site and / or a stenotic common femoral artery, seen on computed tomographic angiography. RESULTS: Surgical haemostasis was performed in 184 (32.4 %, o-T / EVAR group) while percutaneous haemostasis was attempted at 384 sites (67.6 %, p-T / / EVAR group). Most of the procedures were elective; five of twelve emergency patients had percutaneous haemostasis that was successful in all. Percutaneous haemostasis failed at 23 sites. No data about follow-up was recorded for 54 sites (9,5 %). The technical success rate of percutaneous haemostasis was 93.6 % (338 / 361 sites). A larger size of the access site resulted in significantly more complications of haemostasis in both groups (p-T / EVAR group p = 0.019; o-T / EVAR group p = 0.003). p-T / EVAR caused more mild complications compared to o-T / EVAR (p = 0.03). No deaths as consequence of failed haemostasis were recorded. CONCLUSIONS: Complete percutaneous T / EVAR is technically feasible and safe in a majority of patients. Good patient selection based on adequate pre-procedural imaging and technical expertise of the operators are key to success. Surgical back-up is strongly recommended to assist in those patients in whom p-T / EVAR fails.

Osteoblastic bone metastases from renal cell carcinoma.

BACKGROUND: RCC accounts for only 2-3% of all cancers. Due to its' non-specific symptoms disease is often diagnosed in advanced stage. Disseminated RCC frequently produces bone metastases that are almost always highly destructive, hyper vascularized and purely osteolytic. CASE REPORT: In this article we describe a case of a 71-year old male patient with disseminated osteoblastic bone metastases from renal cell carcinoma (RCC), and present a short review of published literature reporting cases of osteoblastic bone metastases from RCC. Our patient presented with thoracic pain aggravated by movement. He was diagnosed with predominantly osteoblastic bone metastases in the skeleton of thoracic and lumbar vertebra along with metastases in iliac bones, ribs, humerus and clavicles. Initially, origin of bone metastases was unknown, but later a small tumor in patient's right kidney was identified. Microscopic evaluation of the open bone biopsy showed clear cell RCC with sarcomatoid differentiation. CONCLUSIONS: Although, due to its' rarity, RCC is not included in the primary differential diagnosis in patients with osteoblastic metastases, such rare cases suggest that RCC may be considered in the diagnosis when there no other primary tumor is found.

Subcutaneous chondromyxoid fibroma with a novel PNISR::GRM1 fusion-report of a primary soft tissue tumour without connection to an underlying bone.

Chondromyxoid fibroma (CMF) is a rare benign bone tumour. While CMF located entirely on the surface of a bone (i.e. juxtacortical CMF) has been well characterised, CMF has not so far been convincingly documented to arise in soft tissues without connection to an underlying bone.We report a subcutaneous CMF in a 34-year-old male, located on the distal medial aspect of the right thigh without any connection with the femur. The tumour measured 15 mm, it was well-circumscribed and displayed typical morphological features of a CMF. At the periphery, there was a small area of metaplastic bone. Immunohistochemically, the tumour cells were diffusely positive for smooth muscle actin and GRM1, and negative for S100 protein, desmin and cytokeratin AE1AE3. Whole transcriptome sequencing revealed a novel PNISR::GRM1 gene fusion.Our case indicates that CMF should be included in the differential diagnosis of soft tissue (including subcutaneous) tumours composed of spindle/ovoid cells, with a lobular architecture and chondromyxoid matrix. The diagnosis of CMF arising in soft tissues can be confirmed by identifying a GRM1 gene fusion or GRM1 expression by immunohistochemistry.

Sonographic assessment of the tarsal tunnel compared to cadaveric findings: a pictorial study.

Aim of the study: To present the anatomy of the tarsal tunnel and demonstrate the utility of high-resolution ultrasound for tarsal tunnel examination. Materials and methods: Anatomical dissection was performed on a defrosted cadaveric model to demonstrate relevant anatomical structures of the tarsal tunnel, namely tendons, vessels and nerves. The tibial nerve division was demonstrated; the bifurcation of the tibial nerve into the medial and lateral plantar nerve, two medial calcaneal nerve branches were identified originating from the tibial nerve and the Baxter's nerve was identified as the first branch of the lateral plantar nerve. An ultrasound examination of the tarsal tunnel region was performed on a healthy volunteer. A linear probe was used and sonographic images were obtained at different levels of the tarsal tunnel: the proximal tarsal tunnel, the tibial nerve division into the medial and lateral plantar nerves, the distal tarsal tunnel, the Baxter's nerve branching point and the Baxter's nerve crossing between the abductor hallucis and quadratus plantae muscle. Results: Sonographic images were correlated with anatomical structures exposed during cadaveric dissection. Conclusions: We presented the anatomic-sonographic correlation of the tarsal tunnel and showed that high-resolution ultrasound is a useful imaging modality for tarsal tunnel assessment.

Assessment of short-term effect of platelet-rich plasma treatment of tendinosis using texture analysis of ultrasound images.

BACKGROUND: Computer-aided diagnosis (i.e., texture analyses) tools are becoming increasingly beneficial methods to monitor subtle tissue changes. The aim of this pilot study was to investigate short-term effect of platelet rich plasma (PRP) treatment in supraspinatus and common extensor of the forearm tendinosis by using texture analysis of ultrasound (US) images as well as by clinical questionnaires. PATIENTS AND METHODS: Thirteen patients (7 male and 6 female, age 36-60 years, mean age 51.2 ± 5.2) were followed after US guided PRP treatment for tendinosis of two tendons (9 patients with lateral epicondylitis and 4 with supraspinatus tendinosis). Clinical and US assessment was performed prior to as well as 3 months after PRP treatment with validated clinical questionnaires. Tissue response in tendons was assessed by using gray level run length matrix method (GLRLM) of US images. RESULTS: All patients improved of tendinosis symptoms after PRP treatment according to clinical questionnaires. Almost all GLRLM features were statistically improved 3 months after PRP treatment. GLRLM-long run high gray level emphasis (LRLGLE) revealed the best moderate positive and statistically significant correlation after PRP (r = 0.4373, p = 0.0255), followed by GLRLM-low gray level run emphasis (LGLRE) (r = 0.3877, p = 0.05). CONCLUSIONS: Texture analysis of tendinosis US images was a useful quantitative method for the assessment of tendon remodeling after minimally invasive PRP treatment. GLRLM features have the potential to become useful imaging biomarkers to monitor spatial and time limited tissue response after PRP, however larger studies with similar protocols are needed.

Single centre experience with Excluder® stent graft; 17-year outcome.

BACKGROUND: Endovascular abdominal aortic aneurysm repair (EVAR) has become a mainstay of abdominal aorta aneurysm treatment. Long term follow-up on specific stent grafts is needed. PATIENTS AND METHODS: This study included 123 patients (104 men; mean age 73.0 years, range 51-89) with abdominal aorta aneurysm, treated with Excluder® stent graft between October 2002 and June 2008. Periprocedural and follow-up data were retrieved by reviewing the records of our institution, while time and cause of death were retrieved from the National Institute of Public Health. If an abdominal aortic aneurysm rupture was listed as the cause of death, records were retrieved from the institution that issued the death certificate. Our primary goal was to assess the primary technical success rate, type 1 and type 2 endoleak, reintervention free survival, 30-day mortality, the overall survival and aneurysm rupture-free survival. RESULTS: The median follow-up was 9.7 years (interquartile range, 4.6-13.8). The primary technical success was 98.4% and the 30-day mortality accounted for 0.8%. Secondary procedures were performed in 29 (23.6%) patients during the follow-up period. The one-, five-, ten-, fifteen- and seventeen-year overall survival accounted for 94.3%, 74.0%, 47.2%, 35.8% and 35.8%, while the aneurysm-related survival was 98.4%, 96.3%, 92.6%, 92.6%, 92.6%. In seven (5.7%) patients, abdominal aortic rupture was found as the primary cause of death during follow-up. CONCLUSIONS: Our data showed that EVAR with Excluder® stent graft offers good long-term results. More than 75% of patients can be treated completely percutaneously. Late ruptures do occur in the first ten years, raising awareness about regular medical controls.

Cone-beam computed tomography guided nusinersen administrations in adult spinal muscular atrophy patients with challenging access: a single- center experience.

BACKGROUND: The challenging anatomic predispositions in adult patients with spinal muscular atrophy (SMA) preclude the conventional lumbar punctures. Consequently, an introduction of alternative method for intrathecal delivery of nusinersen is required. Cone-beam CT (CBCT) allows volumetric display of the area of interest, pre-procedural planning and real time needle guidance which results in accurate anatomic navigation. The aim of the study was to evaluate technical success, safety, and feasibility of CBCT lumbar intrathecal delivery of nusinersen in the adult SMA patients with challenging anatomical access. PATIENTS AND METHODS: Thirty-eight adult SMA patients were treated in our institution. Patients with challenging access were selected by multidisciplinary board for image guided administration of nusinersen either due to implantation of the posterior fusion instrumentation, severe scoliosis defined as Cobb's angle > 40º or body mass index over 35. Technical success, radiation exposure and occurrence of adverse events were assessed. RESULTS: Twenty patients were selected, and 108 CBCT-guided procedures were performed. Each patient underwent at least 4 administrations. Transforaminal approach was performed in 82% of patients. The technical success was 100%, with primary success of 93.5%. The median radiation effective dose of the administrations was 5 mSv, the mean value equalled 10 mSv. Only mild adverse events were reported in the study. CONCLUSIONS: CBCT-guided lumbar intrathecal administrations of nusinersen in an adult SMA population with challenging access was feasible and safe image guided method.

Reliability of haemophilia early arthropathy detection with ultrasound (HEAD-US) in children: a comparative magnetic resonance imaging (MRI) study.

BACKGROUND: Ultrasound (US) has been proven to be reliable in the assessment of early haemophilic arthropathy in the adult haemophilic population, however few studies so far focused on the reliability of US specifically in the paediatric haemophilic population. We were interested if the changing appearance of the growing bone hinders the ultrasonographic evaluation of the pathologic processes caused by haemophilic arthropathy. The aim of the study was to assess the reliability of US for evaluation of haemophilic arthropathy in children in comparison to magnetic resonance imaging (MRI). PATIENTS AND METHODS: The study included all children aged 6 years or more with severe haemophilia in the country (n = 10). We assessed their elbows, knees, and ankles bilaterally by US and compared the results to the MRI as the reference standard. Pearson correlation coefficient (r) was used to analyse correlation. RESULTS: The correlation with MRI for the US for the total score was excellent for all joints (r = 0.849 for the elbows, r = 1 for knees, r = 0.842 for ankles). The correlation of scores for specific joint components showed fair, moderate, or excellent correlation for all joint components in all joints. The correlation was the lowest for the evaluation of cartilage and bone in the ankles (r = 0.546 and r = 0.478) and bone in the elbows (r = 0.499). CONCLUSIONS: Our study proved that US using the HEAD-US method performed by paediatric radiologists is a reliable tool for detection and quantification of haemophilic arthropathy in children in comparison to MRI.

MRI Findings of Early Osteoarthritis in Patients Who Sustained Septic Arthritis of the Knee After ACL Reconstruction.

BACKGROUND: Although a rare complication, septic arthritis (SA) after anterior cruciate ligament (ACL) reconstruction has potentially devastating consequences for the knee joint. PURPOSE: To prospectively analyze, at a mean 4-year follow-up, subjective, clinical, radiographic, and magnetic resonance imaging (MRI) findings between patients with SA and those with no septic complication after ACL reconstruction. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Of 2006 ACL reconstructions performed between 2004 and 2014, a total of 20 patients experienced SA. All patients were treated with arthroscopic irrigation and graft-retaining debridement immediately after diagnosis and at least 6 weeks of antibiotic treatment. After the exclusion process, 18 patients were included in the SA group and 20 in the control group. At final follow-up at a mean 48 months, a physical examination, KT-1000 arthrometer laxity test, Lysholm knee score, Tegner activity score, and International Knee Documentation Committee radiographic score were completed and then compared with preoperative data. The Boston-Leeds Osteoarthritis Knee Score was used for MRI evaluation at final follow-up to note chondral changes. RESULTS: No significant differences between the SA and control groups were observed in pre- and perioperative variables that could indicate a higher incidence of early osteoarthritis (OA). Although range of motion and knee stability were not significantly different between the groups at final follow-up, the Lysholm score (mean ± SD, 79.8 ± 13.1 vs 90.9 ± 8.6; P < .01) and Tegner score (6.0 ± 1.1 vs 7.0 ± 1.4; P = .03) were significantly lower in the SA group as compared with the control group. MRI evaluation at final follow-up demonstrated a significantly higher degree of early knee OA in the SA group versus the control group. However, no differences in the degree of OA were seen on plain radiographs at final follow-up between the groups. CONCLUSION: MRI evaluation provided signs of worsened chondral state in the SA group, which could be associated with reduced functional outcome and return to sports. In contrast to radiograph analyses, MRI was excellent at distinguishing damage to the cartilage and can be useful in early follow-up evaluation of patients with SA after ACL reconstruction.

Ultrasound-guided injections in pelvic entrapment neuropathies.

Pelvic entrapment neuropathies represent a group of chronic pain syndromes that significantly impede the quality of life. Peripheral nerve entrapment occurs at specific anatomic locations. There are several causes of pelvic entrapment neuropathies, such as intrinsic nerve abnormality or inflammation with scarring of surrounding tissues, and surgical interventions in the abdomen, pelvis and the lower limbs. Entrapment neuropathies in the pelvic region are not widely recognized, and still tend to be underdiagnosed due to numerous differential diagnoses with overlapping symptoms. However, it is important that entrapment neuropathies are correctly diagnosed, as they can be successfully treated. The lateral femoral cutaneous nerve, ischiadic nerve, genitofemoral nerve, pudendal nerve, ilioinguinal nerve and obturator nerve are the nerves most frequently causing entrapment neuropathies in the pelvic region. Understanding the anatomy as well as nerve motor and sensory functions is essential in recognizing and locating nerve entrapment. The cornerstone of the diagnostic work-up is careful physical examination. Different imaging modalities play an important role in the diagnostic process. Ultrasound is a key modality in the diagnostic work-up of pelvic entraptment neuropathies, and its use has become increasingly widespread in therapeutic procedures. In the article, the authors describe the background of pelvic entrapment neuropathies with special focus on ultrasound-guided injections.

The role of molecular diagnostics in aneurysmal and simple bone cysts - a prospective analysis of 19 lesions.

Aneurysmal (ABC) and simple bone cysts (SBC) have been traditionally distinguished by radiological and histopathological features. However, there is some radiological and histopathological overlap between ABC and SBC. ABC is characterised by USP6 fusions while, recently, NFATC2 fusions have been found in a large proportion of SBC. Identifying these fusions may assist in confirming the diagnosis of either ABC or SBC. To elaborate the potential benefit of molecular testing, we report a prospective series of 19 consecutive bone cysts with comprehensive radiological, histopathological and molecular diagnostics. Integrating radiological, histopathological and molecular findings, 11 cysts were diagnosed as SBC and 8 as ABC. Radiologically, 6 of 11 SBC and 6 of 8 ABC were diagnosed as ABC. Fibrin-like collagen deposits were identified in 8 of 11 (73%) SBC and 3 of 8 (38%) ABC. Nodular fasciitis-like areas were identified in 6 of 8 (75%) ABC and in 7 of 11 (64%) SBC. A USP6 fusion was identified in all 8 ABC, including a novel RBM5-USP6 fusion. An NFATC2 fusion was found in 7 of 11 SBC (FUS-NFATC2 fusion in 5 and EWSR1-NFATC2 in 2 cases). There is radiological and histopathological overlap between SBC and ABC in a significant proportion of cases. A diagnosis of ABC is frequently suggested radiologically in SBC, and fibrin-like deposits, thought to be specific for SBC, may be found in some ABC. Molecular testing may significantly improve diagnostic accuracy in bone cysts.

Can dynamic imaging, using 18F-FDG PET/CT and CT perfusion differentiate between benign and malignant pulmonary nodules?

BACKGROUND: The aim of the study was to derive and compare metabolic parameters relating to benign and malignant pulmonary nodules using dynamic 2-deoxy-2-[fluorine-18]fluoro-D-glucose (18F-FDG) PET/CT, and nodule perfusion parameters derived through perfusion computed tomography (CT). PATIENTS AND METHODS: Twenty patients with 21 pulmonary nodules incidentally detected on CT underwent a dynamic 18F-FDG PET/CT and a perfusion CT. The maximum standardized uptake value (SUVmax) was measured on conventional 18F-FDG PET/CT images. The influx constant (Ki ) was calculated from the dynamic 18F-FDG PET/CT data using Patlak model. Arterial flow (AF) using the maximum slope model and blood volume (BV) using the Patlak plot method for each nodule were calculated from the perfusion CT data. All nodules were characterized as malignant or benign based on histopathology or 2 year follow up CT. All parameters were statistically compared between the two groups using the nonparametric Mann-Whitney test. RESULTS: Twelve malignant and 9 benign lung nodules were analysed (median size 20.1 mm, 9-29 mm) in 21 patients (male/female = 11/9; mean age ± SD: 65.3 ± 7.4; age range: 50-76 years). The average SUVmax values ± SD of the benign and malignant nodules were 2.2 ± 1.7 vs. 7.0 ± 4.5, respectively (p = 0.0148). Average Ki values in benign and malignant nodules were 0.0057 ± 0.0071 and 0.0230 ± 0.0155 min-1, respectively (p = 0.0311). Average BV for the benign and malignant nodules were 11.6857 ± 6.7347 and 28.3400 ± 15.9672 ml/100 ml, respectively (p = 0.0250). Average AF for the benign and malignant nodules were 74.4571 ± 89.0321 and 89.200 ± 49.8883 ml/100g/min, respectively (p = 0.1613). CONCLUSIONS: Dynamic 18F-FDG PET/CT and perfusion CT derived blood volume had similar capability to differentiate benign from malignant lung nodules.