Imaging of supra-thoracic tuberculosis.

Tuberculosis (TB) typically affects the lungs, but may involve many extra-pulmonary sites; with the latter especially prone in patients with human immunodeficiency virus infection. The clinical features of extra-pulmonary TB are often non-specific, mimicking many different disease entities. Application of the most appropriate imaging modality and knowing the imaging findings with clinical context awareness help initiation of further investigations, diagnosis and early treatment. This pictorial essay highlights the imaging spectrum of extra-pulmonary TB affecting the supra-thoracic region, i.e. brain, neck, and ear, nose and throat.

Can conventional magnetic resonance imaging at presentation predict chemoresistance in osteosarcoma?

OBJECTIVES: Histological tumour necrosis is the current indicator for the response of osteosarcoma after neoadjuvant chemotherapy. Chemoresistant tumours require close monitoring and adjustment of treatment. Characteristics of tumours on baseline MRI may be able to predict response to chemotherapy. The aim is to identify which baseline MRI findings can help predict chemoresistant osteosarcoma. METHODS: Baseline MRI before giving neoadjuvant chemotherapy of 95 patients during 2008-2021 was reviewed by 2 musculoskeletal radiologists. Histological necrosis from surgical specimens was the reference standard. MRIs were reviewed for tumour characteristics (tumour volume, maximum axial diameter, central necrosis, haemorrhage, fluid-fluid level), peritumoural bone and soft tissue oedema, and other parameters including intra-articular extension, epiphyseal involvement, neurovascular involvement, pathologic fracture, and skip metastasis. The cut-off thresholds were generated by receiver operating characteristic curves which then tested for diagnostic accuracy. RESULTS: Two-third of patients were chemoresistance (histological necrosis <90%). Tumour volume >150 mL, maximum axial diameter >7.0 cm, area of necrosis >50%, presence of intra-articular extension, and peritumoural soft tissue oedema >6.5 cm significantly predicted chemoresistance, particularly when found in combination. Tumour volume >150 mL and maximum axial diameter >7.0 cm could be used as an independent predictor (multivariable analysis, P-value = .025, .045). CONCLUSIONS: Findings on baseline MRI could help predicting chemoresistant osteosarcoma with tumour size being the strongest predictor. ADVANCES IN KNOWLEDGE: Osteosarcomas with large size, large cross-sectional diameter, large area of necrosis, presence of intra-articular extension, and extensive peritumoural soft tissue oedema were most likely to have a poor response to neoadjuvant chemotherapy.

Imaging of musculoskeletal tuberculosis.

Extra-pulmonary tuberculosis (TB) of the musculoskeletal system usually manifests with non-specific clinical features, mimicking a variety of diseases. Diagnosis and treatment of spinal and extra-spinal musculoskeletal TB are often challenging. Imaging has an important role in detecting this disease, aiding diagnosis, identifying complications, and monitoring disease progression. Radiographs and magnetic resonance imaging are the key imaging modalities utilized. Radiologists should aim to be familiar with the spectrum of imaging features of TB affecting spinal and extra-spinal locations in the musculoskeletal system.

Imaging of infra-thoracic tuberculosis.

Tuberculosis (TB) is a potentially curable disease that is a leading cause of death globally. While it typically affects the lungs, this disease may involve many extra-pulmonary sites, particularly in patients with risk factors. Extra-pulmonary TB often mimics a variety of different diseases, posing a diagnostic dilemma. Imaging aids in early diagnosis of TB, especially in patients with non-specific or atypical symptoms found at extra-pulmonary infra-thoracic locations. Imaging also helps guide appropriate laboratory investigation, monitor disease progress, and response to treatment. This review aims to highlight the imaging spectrum of TB affecting the infra-thoracic region, that is, gastrointestinal tract, abdominal lymph nodes, peritoneal cavity, intra-abdominal solid organs, and urogenital system.

Pythiosis presenting with chronic swelling and painful subcutaneous lesion at right deltoid.

Pythiosis is a fatal disease which has high incidence in tropical regions. In contrast with vascular pythiosis, cutaneous and subcutaneous pythiosis are both uncommon. Here, we report a case of subcutaneous pythiosis in a pregnant farmer manifested with a progressively larger and more painful mass at right deltoid. The tissue culture and molecular test were negative for fungi. The diagnosis was supported by the positivity of serum immunochromatographic test (ICT) for pythiosis. Patients responded well to the combination therapy of itraconazole, terbinafine and azithromycin.

Benign incidental do-not-touch bone lesions.

Benign bone lesions may occasionally be incidentally detected on radiographs and are also increasingly found on CT or MRI performed for other clinical indications. Although mostly asymptomatic or associated with minor symptoms, these lesions may simulate true pathological lesions, causing problems in diagnosis. For instance, asymptomatic benign bone lesions can be misinterpreted as metastasis when incidentally encountered in a patient with known cancer. Recognising these entities as "do-not-touch" lesions helps avoid unnecessary further investigation or harmful intervention. In this review, we highlight three groups of bone incidentalomas found in adults, namely: osteolytic lesions, osteoblastic lesions, and bone protuberances. We aim to review the key imaging features of selected common and less common conditions in these three groups, so as to help radiologists confidently identify these benign do-not-touch lesions and to distinguish them from more sinister pathological lesions.

Osteocutaneous proximal fibular flap: an anatomical and computed tomographic angiographic study of skin and bone perforators.

INTRODUCTION: Vascularized proximal fibular epiphyseal transfer is a reconstruction method for joints and growing bones. The authors investigated the vascular supply of the proximal fibula, including skin perforators, for suitability in creating an osteocutaneous flap. METHODS: Twenty fresh cadaveric knees were studied using computed tomographic angiography combined with anatomical dissection. Three-dimensional angiography was used to develop an overview, and multiplanar two-dimension angiography was used for detailed data collection. Anatomical dissection verified by angiography was used to locate skin perforators of the proximal part of the anterior tibial artery. RESULTS: Proximal fibular bone perforators from the anterior tibial artery were found to arise either from the anterior tibial recurrent artery, the posterior tibial recurrent artery or the circumflex fibular artery in every specimen (100%), whereas perforators from the inferolateral genicular artery met those criteria in 12 of 18 specimens (66.7%). In the proximal half of 20 anterior tibial arteries, 129 skin perforators with a diameter larger than 0.5 mm were found. There were 54 potential septocutaneous skin perforators between the extensor digitorum longus and the peroneus longus muscles (EDL/PL), and 18 between the extensor digitorum longus and the tibialis anterior muscles (TA/EDL). Skin perforators from the inferolateral genicular artery emerging from the posterolateral corner of the knee had a diameter of < 0.5 mm. CONCLUSION: Based on this cadaveric study, the reverse flow anterior tibial artery pedicle and the EDL/PL or TA/EDL skin perforators can be considered as options for osteocutaneous proximal fibular transfers.

Imaging of intramuscular haemangiomas of the extremities.

Intramuscular haemangiomas are benign soft tissue tumours that are more frequently seen in children and young adults. As they may be difficult to diagnose clinically, imaging has an important role in the detection, diagnosis and preoperative planning of these lesions. Haemangiomas of the extremities may be classified into capillary, cavernous, venous and mixed types, with or without an arteriovenous shunt, depending on the predominant vascular channels. Nonvascular components such as fat, smooth muscle, fibrous tissue and thrombus may also be present. This pictorial essay highlights the imaging features of intramuscular haemangiomas, with an emphasis on magnetic resonance imaging.

Comparison of three-dimensional and two-dimensional computed tomographies in the classification of acetabular fractures.

PURPOSE: This study compared the accuracy and timeliness of two-dimensional computed tomography (2DCT) and three-dimensional computed tomography (3DCT) in the diagnosis of different types of acetabular fractures and by different groups of interpreters using the Letournel and Judet classification system. METHODS: Twenty-five fractures cases, five each of five common types of acetabular fractures, were selected. Nineteen interpreters with different levels of experience (ten graduate trainees and nine radiologists) individually classified the fractures using multiplanar 2D and standardized 3DCT images. The 3DCT image set was comprised of 39 images of rotational views of the entire pelvis and the disarticulated fracture hip. Consensus reading by three experts served as a reference standard. RESULTS: Classification accuracy was 66% using 2DCT, increasing to 73% (p = 0.041) when 3DCT was used. Improvement occurred in the interpretation of transverse and posterior wall-type fractures (p < 0.01 and p = 0.015, respectively), but not in T-type, transverse with posterior wall, or both-column fractures. The improvement was noted only in the graduate trainee group (p = 0.016) but not the radiologist group (p = 0.619). Inter-observer reliability in the graduate trainee group improved from poor to moderate with 3DCT, but remained at a moderate level in both 2DCT and 3DCT in the radiologist group. The overall average interpretation time per case with correct diagnosis was 60 s for 2DCT but only 32 s for 3DCT. CONCLUSIONS: Standardized 3DCT provides greater reliability and faster diagnosis of acetabular fractures and helps improve the accuracy in transverse- and posterior wall-type fractures. In addition, it helps improve the accuracy of less experienced interpreters.

Efficacy of three-dimensional cinematic rendering computed tomography images in visualizing features related to age estimation in pelvic bones.

Morphological changes on the surface of the pelvic bone can be used to estimate the age at death of a person. These features can be visualized using three dimensional computed tomography (3D CT) images. A newly introduced 3D CT technique, cinematic volume rendering, improves visualization of the surface of bones by integrating the effect of light on the images. The aim of this study is to evaluate the efficacy of this 3D CT technique in visualizing features related to age estimation in pelvic bones. Dry pelvic bones of 35 subjects were scanned and then 3D reconstruction of the images was performed using the cinematic rendering technique. The 3D CT images of the pubic symphyses and the auricular surfaces were interpreted by two radiologists and a forensic osteologist using age estimation features derived from the Suchey-Brooks and the Buckberry-Chamberlain methods The interpretation of the dry pelvic bones was done by an expert anatomist and used as a gold standard. The percentages of correct interpretations and level of agreement in grading using 3D CT and using dry bones were high for features in the pubic symphyses including surface patterns (100%, k=1), presence of lower extremities (100%, k=1), and patterns of pubic rims (91.4%, range 87.5-100%, k=0.88). In the auricular surface of the ilium, all specimens with an apical activity were correctly interpreted (100%, k=1), but detection was moderate to poor for transverse organization (71.4%, k=0.43), macroporosity (70%, k=0.38.), and microporosity (52.9%, k=0.25). Cinematic volume rendering has a high level of efficacy in identifying age-related features on pubic symphyses, but it inadequately displays features on the auricular surface.

Spindle Cell Hemangioma of the Midfoot: A Case Report.

INTRODUCTION: Spindle cell hemangioma (SCH) of the bone (midfoot) is a rare disease, but it can cause symptomatic pain and invade surrounding tissues lead to limb deformities and functional loss. CASE REPORT: We report the case of a 35-year-old woman who experienced a firm mass over the left midfoot for 5 years causing pain and numbness in the foot. Radiographs showed a geographic osteolytic lesion involving calcification of the base of the 2nd and 3rd metatarsals, cuneiforms bones and surrounding soft tissue. Magnetic resonance imaging revealed a lobulated mass in the midfoot containing tangles of tortuous blood vessels and dark foci characteristic of phleboliths. Wide resection of the 2nd and 3rd cuneiforms, metatarsal bones and surrounding tissues with a curved iliac bone graft reconstruction were performed. Histological assessment revealed a lesion composed of a vascular channel containing endothelial cells with smooth muscle but without cellular atypia. The definite diagnosis was spinal cell hemangioma. The pain resolved within 4 months. The foot was stable, and no recurrence was found at the 48 months follow-up. CONCLUSION: This unusual disease, SCH of the midfoot responded favorably to wide resection and curved iliac bone grafting. It is suggested that this approach will provide a satisfactory functional result.

Ankle ligament reconstruction after wide resection of the osteosarcoma of the distal fibula: a case report.

BACKGROUND: Restoration of the lateral ankle after distal fibulectomy is a difficult reconstructive procedure. Many surgical techniques have been proposed. This report shows another fibular reconstructive option with promising outcome. CASE PRESENTATION: We report the case of a 30-year-old woman who presented with a solitary mass located in the lateral aspect of the ankle. The mass had grown rapidly for 2 months and caused increasing pain. Physical examination showed a 3.0 cm diameter tender, nonmobile hard mass in the lateral malleolus. Radiographs showed an osteolytic lesion involving the lateral cortex at the distal fibula. After incisional biopsy, pathologic examination found a well-differentiated intramedullary osteosarcoma. Neoadjuvant chemotherapy with doxorubicin was provided for 3 months prior to definitive surgical treatment. Magnetic resonance imaging showed persistent tumor in the biopsy site. After distal fibulectomy and wide resection, split tibialis posterior tendon transfer to the remaining peroneus brevis restored the stability of the ankle. The pain resolved within 3 months. The ankle was stable and no recurrence of the cancer was found at a 7 year follow-up. CONCLUSION: Reconstruction following distal fibulectomy and surrounding soft tissue resection responds favorably to split tibialis posterior transfer to the remaining peroneus brevis suggesting that this technique can provide a good and functional outcome.

Effectiveness of sonography assisted minimal invasive plate osteosynthesis (MIPO) compare with fluoroscope assisted in femoral shaft fracture: A cadaveric study.

INTRODUCTION: A minimal invasive plate osteosynthesis (MIPO) has an advantage of biological soft tissue preservation that consists of preserving bony blood supply, fracture hematoma and less soft tissue damage which leads to decreasing of infection rate and rapid bone healing. However, the radiation exposure is still a disadvantage of this technique. A sonography that provides dynamic real time imaging may be used as an alternative technique for assisting MIPO. The aim of this study was to compare the effectiveness of MIPO in femoral shaft fracture between the sonography assisted and the fluoroscopy assisted. METHODS: Twenty-eight cadaveric limbs were subjected to create femoral shaft fracture. Then, sonography assisted reduction with temporary external fixation and MIPO were performed. Images of the sonography and the fluoroscopy were recorded including before reduction, after reduction and after MIPO in order to identify fracture displacements in anteroposterior and mediolateral directions. Moreover, the anterior and posterior distances from edge of the bone to the plate were measured to confirm plate position. The effectiveness of this technique was defined as the proper plate position and acceptable alignment after fixation. All distances from the sonography and the fluoroscopy were also analyzed and compared using Pearson correlation and Bland-Altman method to assess the agreements between two tests. RESULT: All of the subjects were met the criteria for acceptable alignment. We found only three femoral shaft fracture (11%) operated with MIPO by sonography assisted that showed slipped plate off femoral bones. According to Pearson correlation, there were good to excellent agreements in term of measuring fracture displacement before (Pearson Correlation >0.7) and after reduction (Pearson Correlation >0.7) between these two tests. There was moderate agreement regarding to evaluation of plate position (Pearson Correlation 03.-0.7). When we compared two methods of measurement using Bland-Altman plot, there were no statistical significant difference (P<0.05). CONCLUSION: Images from the sonography could provide visualization of the fracture during reduction and MIPO as accurately as the radiography. Thus, the sonography assisted MIPO in femoral shaft fracture can be done effectively comparing with radiographic assisted.

Age estimation by chest plate radiographs in a Thai male population.

Costal cartilage ossification on chest plate radiographs is one of the useful methods in age estimation for adults. This study was performed in 136 remains yielding a regression formula for age estimation in Thai male population. Eight features on chest plate imaging were scored based on Garvin's method. Composite scores were calculated by summation of all scores and analyzed to generate the regression of age as: Age=16.664×e0.161 (composite score) with a 95% prediction interval. The predicted age intervals in all composite scores were overlapping except for score 0 and 7. It could be concluded that if all features are absent/present, the person is likely to be less/more than 29years old.

Value of ultrasonography in the diagnosis of gout in patients presenting with acute arthritis.

OBJECTIVE: To evaluate the value of ultrasonographic features of crystal deposition for diagnosing gout in patients presenting with acute arthritis. MATERIALS AND METHODS: Ultrasound scanning of the most inflamed joint was performed on 89 consecutively enrolled patients with acute arthritis. Two radiologists independently reviewed the ultrasound images, and a consensus was achieved with a third radiologist when the interpretations of four key ultrasound features of gout differed. Arthrocentesis and crystal analysis using compensated polarized light microscopy of aspirates are considered the gold standards for gout diagnosis. RESULTS: Fifty-three (60%) patients had gout, whereas the remaining 36 (40%) had non-gout arthritis. The mean serum uric acid level was 7.1 mg/dl in patients with gout and 4.7 mg/dl in patients with non-gout arthritis. Three US features differed significantly (p < 0.001) between patients with gout and non-gout arthritis: the double contour sign (42 vs. 8%, respectively), intra-articular aggregates (58 vs. 8%), and tophi (40 vs. 0%). No statistically significant differences in detecting intra-tendinous aggregates (32 vs. 17%, p = 0.14) were observed. The sensitivity and specificity of the double contour sign were 42 and 92%, respectively; those of the intra-articular aggregates were 58 and 92%; and those of tophi were 40 and 100%. The positive predictive values for these three features ranged from 88 to 100%, whereas the negative predictive values ranged from 52 to 60%. CONCLUSIONS: When the prevalence is high, these three ultrasound features may be a useful adjunct in the diagnosis of acute gout, particularly when specialized microscopic techniques are not available.

Performance of the 2015 American College of Rheumatology/European League Against Rheumatism gout classification criteria in Thai patients.

To evaluate the sensitivity and specificity of the 2015 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) gout classification criteria in Thai patients presenting with acute arthritis in a real-life setting. Data were analyzed on consecutive patients presenting with arthritis of less than 2 weeks duration. Sensitivity and specificity were calculated by using the presence of monosodium urate (MSU) crystals in the synovial fluid or tissue aspirate as gold standard for gout diagnosis. Subgroup analysis was performed in patients with early disease (≤2 years), established disease (>2 years), and those without tophus. Additional analysis also was performed in non-tophaceous gout patients, and patients with acute calcium pyrophosphate dihydrate crystal arthritis were used as controls. One hundred and nine gout and 74 non-gout patients participated in this study. Full ACR/EULAR classification criteria had sensitivity and specificity of 90.2 and 90.0%, respectively; and 90.2 and 85.0%, respectively, when synovial fluid microscopy was excluded. Clinical-only criteria yielded sensitivity and specificity of 79.8 and 87.8%, respectively. The criteria performed well among patients with early and non-tophaceous disease, but had lower specificity in patients with established disease. The variation of serum uric acid level was a major limitation of the classification criteria. The ACR/EULAR classification criteria had high sensitivity and specificity in Thai patients presenting with acute arthritis, even when clinical criteria alone were used.

Multiple Neuromas Cause Painful "Jumping Stump" in a Transfemoral Amputee: A Case Report.

Painful "jumping stump" is an uncommon but very disturbing complication postamputation. This condition is one of the movement disorder entities resulting from peripheral nerve pathology, often known as "peripherally induced movement disorders." Previously case reports have been written about painful and nonpainful incidence of "jumping stump"; however, only the earliest "jumping stump" article in 1852 suspected that neuromas might influence the involuntary movement. In this study, we describe a 38-year-old man with bilateral transfemoral amputee who suffered from painful "jumping stump" with multiple neuromas confirmed by imaging. He was treated successfully by ultrasound-guided phenol injection into the sciatic neuroma stalks. The pathophysiology of jumping stump and its possible association with neuroma are briefly discussed.

Acute bone infarction: a rare complication in thalassemia.

Acute bone infarction is a well-described complication in sickle cell hemoglobinopathy but it is rarely reported in patients with thalassemia. This report describes an 18-year-old man with homozygous ß-thalassemia presenting with a fever and severe acute bilateral ankle pain. The acute onset of severe pain and fever were clinical mimics of infectious arthritis and osteomyelitis. Magnetic resonance imaging revealed acute bone infarction in the meta-diaphysis of bilateral tibias presenting as central unenhanced devitalized bone with T1-high signal intensity fluid in the subperiosteum and soft tissue. Characteristic imaging features are discussed, emphasizing the benefit of fat suppression pre-and post-intravenous gadolinium T1-weighted images. The etiologies of bone infarction in thalassemia are reviewed.

Performance of the Existing Classification Criteria for Gout in Thai Patients Presenting With Acute Arthritis.

Currently, there are 5 existing classification criteria for gout: the Rome, New York, American Rheumatism Association (ARA), Mexico, and Netherlands criteria. This study was carried out to determine the performance of these classification criteria in Thai patients presenting with acute arthritis.All consecutive patients presenting with acute arthritis and being consulted at the Rheumatology Unit, Chiang Mai University Hospital from January 2013 to May 2015 were invited to join the study. Gout was defined by the presence of monosodium urate crystals in the synovial fluid or tissue examined by experienced rheumatologists. The 5 existing gout classification criteria were performed and evaluated in all of the patients, who were divided in subgroups of early disease (≤2 years), established disease (>2 years), and those without tophus.There were 136 gout and 97 nongout patients. Sensitivity and specificity across all criteria ranged from 75.7% to 97.1% and 68.0% to 84.5%, respectively. Overall, the Mexico criteria had the highest sensitivity (97.1%), and the ARA survey criteria the highest specificity (84.5%), whereas the Mexico criteria performed well in early disease with sensitivity and specificity of 97.1% and 81.7%, respectively. All 5 criteria showed high sensitivity (from 76.4% to 99.1%) but low specificity (from 30.8% to 65.4%) in established disease. In patients without tophus, the sensitivity and specificity ranged from 64.1% to 95.7% and 68.8% to 85.4%, respectively. The ARA survey criteria across all groups showed consistently high specificity for gout.The 5 existing classification criteria for gout had limited sensitivity and specificity in Thai patients presenting with acute arthritis. The ARA survey criteria are the most suitable for diagnosing gout in Thai people when crystal identification is not available.

Age estimation of a Thai population based on maturation of the medial clavicular epiphysis using computed tomography.

Ossification of the medial clavicular epiphysis plays an essential role in age estimation for forensic analyses. This study was designed to assess clavicular development in a Thai population using thin-slice computed tomography. Ossification status of the medial clavicular epiphysis was determined in 409 patients using a 5 stage classification by Schmeling et al. Stages 2 and 3 were further subclassified into early (stage a), intermediate (stage b), and late phases (stage c) using criteria from Kellinghaus et al. The sub-stage classification increased accuracy of age estimation particularly within stage 3. Results from this study can be used as a more accurate, Thai specific reference for estimating age. For Thai legal proceedings, we recommend using stage 4 of maturation to represent age>18 years and stage 5 occurring at >20 years.