Neoplasms of the perivascular epithelioid cell involving the abdomen and the pelvis: cross-sectional imaging findings

Neoplasms of the perivascular epithelioid cell (PEComas) represent a recently described heterogeneous group of mesenchymal tumors characterized by the presence of specific histological, immunohistochemical, and ultrastructural findings. The PEComas encompass a family of neoplasms that include angiomyolipomas, clear cell sugar tumors, and lymphangioleiomyomatosis. The PEComas demonstrate a wide spectrum of clinicobiological behavior and imaging findings. Perivascular epithelioid cell, as the name implies, is a unique cell that is characterized by perivascular distribution and epithelioid morphology. Perivascular epithelioid cell consistently shows immunoreactivity to melanocytic and smooth muscle markers including HMB-45 and actin. Abdominopelvic PEComas are found at a variety of somatic and visceral locations including kidney, liver, pancreas, gastrointestinal tract, genitourinary tract, peritoneum, and retroperitoneum. A subset of patients with abdominopelvic PEComas manifests tuberous sclerosis complex. In this paper, we review the histological spectrum and discuss the imaging findings of the PEComas that involve the abdomen and pelvis.     

Primary perivascular epithelioid cell neoplasm (PEComa) of bone: Report of two cases and review of the literature

Primary perivascular epithelioid cell neoplasms (PEComas) of bone are rare mesenchymal tumors. Histologically, they are composed predominantly of perivascular epithelioid cells and have the capacity to metastasize. PEComas have been reported within intra-abdominal and intra-pelvic organs. To the best of our knowledge, only seven primary PEComas of bone have been described in the English literature. We present two cases of PEComa of bone, one arising from the distal fibula and one from the acetabulum. Both were treated by surgical excision and one also received adjuvant chemotherapy.     

Metastatic PEComa arising from renal angiomyolipoma: MRI findings

The perivascular epithelioid cell tumor (PEComa) is a neoplasm composed primarily of HMB-45-positive epithelioid cells with a perivascular distribution. Both benign and malignant PEComas have been reported in diverse anatomic locations. We report the MRI features of a metastatic PEComa to the liver that originated within a renal angiomyolipoma (AML).     

Malignant PEComa of the lumbar vertebra: a rare bone tumour

We describe the case of a 26-year-old patient with a perivascular epithelioid cell tumour (PEComa) involving the 5th lumbar vertebra. Radiological findings, pathological features and treatment are presented. We conclude that PEComas should be considered in the differential diagnosis of vertebral lesions.     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Old and dangerous: Prison and dementia

Older prisoners are the fastest growing group of prisoners in many countries. The purpose of this study is to explore the phenomenon of detention of persons suffering from dementia. Medline searches were conducted for relevant articles, chapters and books published until August 2016. Search terms included dementia, elderly, prison and criminal. Publications found through this indexed search were reviewed for further relevant references. As results, there is a lack of data about elderly with dementia in prisons. Given the rise in the average age, it is reasonable to hypothesize that the number of older prisoners is growing. Moreover, some elderly are imprisoned with a concomitant cognitive impairment or psychiatric disorder while others will develop such diseases once incarcerated. At the present time, legal and social systems seem unprepared to handle the phenomenon of dementia in prison. As proposal, health assessments for older first time offenders should become a practice inside the correctional facilities and include an evaluation for specific health issues, such as psychiatric comorbidity and cognitive impairment.     

Concentric and eccentric shoulder and elbow muscle strength in female volleyball players and non-active females

Alfredson H, Pietilä T, Lorentzon R. Concentric and eccentric shoulder and elbow muscle strength in female volleyball players and non-active females. Maximal isokinetic concentric (60°/s and 180°/s) and eccentric (60°/s) muscle strength of the external and internal rotator muscles of the shoulder and the flexor and extensor muscles of the elbow was measured in a position resembling spiking and serving in volleyball, on 11 non-injured female volleyball players (first division) and 11 non-active females. In the dominant arm, the volleyball players had significantly higher concentric peak torque of the internal and external rotators and elbow extensors at both velocities, and significantly higher eccentric peak torque of the shoulder internal and external rotators and elbow flexors and extensors, than the controls. In the volleyball group, the concentric internal rotation peak torque at 60°/s was significantly higher in the dominant than in the non-dominant arm. The external/internal strength ratio was significantly lower at 60°/s, but not at 180°/s, in the dominant arm. Conclusion: The female volleyball players had a higher concentric and eccentric strength in the rotator muscles of the shoulder and in the extensor muscles of the elbow compared to untrained controls in this special test position. There were signs of rotator muscle imbalance at the low test speed, but no signs of weakness of the external rotators, in the dominant arm of the volleyball players.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

Staging and surgical management of pancreatic and biliary cancer and inflammation

Management of benign and malignant diseases of the pancreas, liver, and biliary tract has made remarkable progress in the last two decades. Advances in minimally invasive surgery, interventional radiology, and diagnostic and therapeutic endoscopy have changed the treatment of common diseases such as cholelithiasis and more serious diseases such as pancreatic adenocarcinoma. Advances in biliary tract and pancreatic surgery have paralleled the advances in ultrasonographic imaging, CT, and MR imaging. This article outlines the surgeon's perspective on radiologic imaging and preoperative staging of benign and malignant biliary and pancreatic disease.     

Radiographers and radiologists reporting plain radiograph requests from accident and emergency and general practice

AIM: To assess selectively trained radiographers and consultant radiologists reporting plain radiographs for the Accident and Emergency Department (A&E) and general practitioners (GPs) within a typical hospital setting. METHODS: Two radiographers, a group of eight consultant radiologists, and a reference standard radiologist independently reported under controlled conditions a retrospectively selected, random, stratified sample of 400 A&E and 400 GP plain radiographs. An independent consultant radiologist judged whether the radiographer and radiologist reports agreed with the reference standard report. Clinicians then assessed whether radiographer and radiologist incorrect reports affected confidence in their diagnosis and treatment plans, and patient outcome. RESULTS: For A&E and GP plain radiographs, respectively, there was a 1% (95% confidence interval (CI) -2 to 5) and 4% (95% CI -1 to 8) difference in reporting accuracy between the two professional groups. For both A&E and GP cases there was an 8% difference in the clinicians' confidence in their diagnosis based on radiographer or radiologist incorrect reports. For A&E and GP cases, respectively, there was a 2% and 8% difference in the clinicians' confidence in their management plans based on radiographer or radiologist incorrect reports. For A&E and GP cases, respectively, there was a 1% and 11% difference in effect on patient outcome of radiographer or radiologist incorrect reports. CONCLUSION: There is the potential to extend the reporting role of selectively trained radiographers to include plain radiographs for all A&E and GP patients. Further research conducted during clinical practice at a number of sites is recommended.     

Mechanomyography and electromyography during and after fatiguing shoulder eccentric contractions in males and females

The aim of this study was to investigate changes in mechanomyographic (MMG) and the surface electromyographic (EMG) signals during and after fatiguing shoulder eccentric contractions in a group consisting of 12 males and 12 females. Exerted force, MMG, EMG, pain and rate of perceived exertion were assessed before, during and after repeated high-intensity eccentric exercises. Bouts of eccentric contractions caused a decrease in the exerted force for males (P<0.05) and an increase in the rate of perceived exertion and pain for both genders (P<0.05). During eccentric exercise, the root mean square (RMS) values of the MMG signal increased (P<0.05). The mean power frequency (MPF) values of the EMG signal decreased at the end of each eccentric bout for both genders (P<0.05); the decrease was higher for females compared with males (P<0.05). Immediately after eccentric exercise in static abduction of the upper limbs, the MMG RMS and MPF values increased (P<0.05). The present study showed that (1) neuromuscular changes associated with pain and changes in muscle stiffness and (2) changes in motor units strategy during fatigue development in shoulder muscle are reflected in the MMG and EMG signals.     

Baseline anthropometry, flexibility and strength characteristics and future low-back pain in adolescent athletes and nonathletes

Factors associated with low-back pain were sought by examining physical activity, low-back pain reports and physical measurements in 86 athletes and 33 nonathletes, a total of 119 adolescents (52 boys and 67 girls). The athletic boys participated in team sports (19 in soccer and 17 in ice hockey) and the athletic girls in individual sports or dance (14 in gymnastics, 17 in figure skating, and 19 in ballet). All subjects answered a questionnaire on physical activity and pain history at the beginning of the study and at the 1-year follow-up. At the beginning of the study, the subjects also participated in quantitative measurements of anthropometry, flexibility (joint hypermobility and muscular tightness), and strength. In multivariate analysis, decreased lumbar flexion and hip flexor tightness at the baseline were predictive of low-back pain among boys during the follow-up. Among girls higher than average body weight at the baseline and low-back pain during the 12 months preceding the baseline measurements were predictive of low-back pain during the follow-up. However, the differences between the groups with and without low-back pain were small compared with the differences between different physical activity groups. In conclusion, attention should be focused on low-back pain, which accumulates in adolescent athletes participating in individual sports, such as figure skating and gymnastics. Our results suggest that flexibility and strength measurements are weak predictors in determining athletes at high risk.     

Bone and soft tissue tumors of hip and pelvis

Objective is to identify epidemiologic and radiologic criteria allowing specific diagnoses of tumors and tumor-like lesions in the hip region and pelvis, and to optimize pre-operative staging. Patients with pelvic tumors are usually older, and their tumors are larger relative to patients with tumors in extremities. The majority of tumors in the pelvis are malignant (metastases, myeloma, chondrosarcoma, Ewing-, osteo-, and MFH/fibrosarcoma), while those in the proximal femur are in majority benign (fibrous dysplasia, solitary bone cyst, and osteoid osteoma). Soft tissue masses in the thigh in the elderly are typically sarcomas without tumor specific signs. Common tumor-like lesions occurring in the hip and pelvis that can mimic neoplasm are: infections (including tuberculosis), insufficiency/avulsion fractures, cysts, fibrous dysplasia, aneurysmal bone cyst, Langerhans cell histiocytosis, and Paget's disease. Local MR staging is based on the compartmental anatomy. The psoas and gluteal muscles are easily invaded by sarcoma originating in the ileum. The pectineus muscle protects the neurovascular bundle at the level of the hip. The thigh is separated into three compartments, some structures (Sartorius muscle) cross borders between compartments. Immobile joints (SI-joints, osteoarthritic hip) are relatively easily crossed by sarcoma and giant cell tumor.     

The thyroid and parathyroid glands. CT and MR imaging and correlation with pathology and clinical findings

Thyroid imaging approach is based on the preliminary clinical evaluation. Lesions that are smaller than 2 cm should be assessed with US, which is capable of discriminating masses as small as 2 mm and distinguishing solid from cystic nodules. US-guided FNAB provides tissue for cytologic examination of thyroid nodules. CT and MR imaging are indicated for larger tumors (greater than 3 cm diameter) that extend outside the gland to adjoining structures, including the mediastinum, and retropharyngeal region. Metastatic lymph nodes in the neck and invasion of the aerodigestive tract are also in the realm of CT and MR imaging. Thyroid nodules are categorized on scintigraphy as hot or cold nodules. Hot nodules are rarely malignant, whereas cold nodules have an incidence of 10% to 20% of malignancy. Calcifications (amorphous, globular, nodular, and linear) occur in adenomas and carcinomas and have no differential diagnostic features except for psammomatous calcifications, which are a pathognomonic finding in papillary carcinomas and a small percentage of medullary carcinomas. Papillary carcinoma is the most common malignant tumor (80%) followed by follicular (20% to 25%); medullary (5%); undifferentiated; anaplastic carcinomas (< 5%); lymphoma (5%); and metastases. Lymph node metastases are common in papillary carcinoma, 50% at presentation, and less common in follicular carcinomas. The metastatic nodes in papillary carcinoma may enhance markedly (hypervascular); show increased signal intensity on T1-weighted images (increased thyroglobulin content or hemorrhage); and reveal punctate calcifications. Localized invasion of the larynx, trachea, and esophagus occurs predominantly in papillary and follicular carcinomas; the incidence is less than 5%. Ectopic thyroid tissue may be encountered in the tongue (foramen cecum); along the midline between posterior tongue and isthmus of thyroid gland; lateral neck; mediastinum; and oral cavity. Goiter and malignant tumors, notably papillary carcinoma, may develop in ectopic thyroid tissue. Carcinomas may also arise in thyroglossal duct cysts, which develop from duct remnants between the foramen cecum and thyroid isthmus. Infectious disease of the thyroid gland is not common and the CT and MR imaging findings are similar as described under neck infection. Other types of inflammatory disorders including Hashimoto's thyroiditis, granulomatous thyroiditis, and Riedel's struma display no specific imaging features. Imaging studies may, however, be indicated to confirm a suspected clinical diagnosis and assess compromise of the airway (Riedel's struma). HPT is a clinical diagnosis in which hypercalcemia is the most important finding. Parathyroid hyperplasia, adenoma, and carcinoma represent underlying lesions. To relieve the patient's symptoms surgical extirpation is indicated. The surgical success rate without imaging is 95%. The indications for imaging studies vary but it is generally agreed that reoperation after a previous failed surgical attempt and suspicion of an ectopic parathyroid adenoma should be investigated by imaging. These consist of US, nuclear medicine studies, CT and MR imaging. US and technetium sestamibi scanning have the highest accuracy rate for localizing an adenomatous gland at and near the thyroid gland. Ectopic adenomas, particularly if they are located in the mediastinum, are preferrably investigated with CT and MR imaging with gadolinium and fat suppression. Carcinomas and parathyroid cysts are optimally evaluated by CT and MR imaging. On MR imaging adenomas are low in signal intensity on T1-weighted images, high in signal intensity on T2-weighted images, and enhance post introduction of gadolinium.     

Cardiac and vascular imaging with labeled platelets and leukocytes

The contribution of platelets in atherosclerosis and thrombosis in animal models and in clinical studies has been quantified with 111In-platelet scintigraphy. New in vitro quantitative techniques have been developed using 111In-labeled platelets to determine the number of adherent platelets on deendothelialized surfaces of damaged vessel walls and synthetic vascular grafts. In vivo imaging techniques are semi-quantitative in nature; in these studies 111In radioactivity on thrombotic vessels or graft surfaces of iliac, femoral, or popliteal arteries is compared with contralateral vessels. Background 111In radioactivity in the circulating blood pool of venous and capillary networks and radioactivity in marrow decreases the sensitivity of these techniques. Despite these limitations, the dynamic process of platelet deposition in most of the denuded, atherosclerotic vessels and prostheses in the circulatory system can be recorded. This ongoing thrombosis and embolization has been observed in 5-10-year-old vascular grafts of Teflon and Dacron biomaterials. Currently used platelet function inhibitor drugs, eg, aspirin, Persantine, sulfinpyrazone, and Motrin, have a demonstrable effect on platelet deposition. Slight changes in reduction of platelet deposition on these surfaces due to medical intervention have been observed by noninvasive imaging with 111In-platelets. Subtraction of blood pool radioactivity with 99mTc-labeled autologous red cells and calculation of 111In radioactivity associated with platelet thrombus on vessel walls also have been performed for coronary, carotid, and femoral arteries. Although platelet concentrates are used frequently after open heart surgery (one to six per patient), consumption of platelets in the artificial lung or oxygenator, lysis of platelets during pumping, and suction of blood only recently have been quantified with the use of 111In-labeled platelets. These studies also demonstrated far less trauma to platelets with the use of a membrane rather than a bubble oxygenator. Further reduction in platelet consumption and trauma was observed with the use of prostacyclin, a short-acting drug with significant beneficial effect on platelet thrombus reduction and disaggregation of aggregated platelets. The role of polymorphonuclear leukocytes in inflammation, infection and myocardial infarction, and in vivo evaluation with 111In-leukocyte scintigraphy in animals and humans has been described.(ABSTRACT TRUNCATED AT 400 WORDS)     

脊索瘤的C T、MR I表现及其误诊分析

目的：探讨脊索瘤的CT、MRI表现及分析其误诊原因。方法回顾性分析18例脊索瘤 CT、MRI 图像,对术前诊断错误者进行影像分析及总结。结果术前12例诊断正确,6例误诊。颅底部9例,骶尾部8例,颈椎1例。CT与 MRI显示病灶呈圆形或类圆形12例,不规则形6例;14例边界清楚,4例边界不清。CT见膨胀性溶骨性骨质破坏,肿块呈不均匀等密度或稍低密度;9例病灶内或周边见点片状钙化或残存骨质。MRI示病灶呈等稍低T1 WI、高T2 WI信号;CT及 MRI增强后肿块呈不均匀轻中度强化。结论脊索瘤具有一定的CT、MRI特征,CT与 MRI结合对脊索瘤的定位、定量、定性诊断具有重要的价值。     

Metabolic and cinematographic analysis of walking and running in men and women

The purposes of this study were to compare the total metabolic costs and gait patterns of walking and running at self-selected, comfortable speeds in males and females. Total oxygen consumption was used to determine the metabolic cost, and cinematographic analysis was used to study the gait patterns of walking and running a distance of 1 km in 12 male and 12 female subjects. No significant sex difference was observed for the speed, vertical lift per stride, and total vertical lift per km of distance walked. Females ran at a significantly slower speed than males (P less than .01), but no significant sex difference was observed for the vertical lift per stride or total vertical lift per km of distance run. In both sexes, the gross and net energy costs of running were significantly greater (P less than .001) than those of walking when values were expressed as kcal . kg-1 . km-1 or cal . kg-1 . stride-1. No significant sex difference was observed in the gross or net metabolic cost of walking, whereas during running, the gross and net metabolic costs in kcal . kg-1 . km-1 were significantly higher (P less than .05) in females than in males. It was hypothesized that this sex difference was due to the cumulative effect of several factors which were biomechanical and metabolic in nature.     

颅内血管周细胞瘤与脑膜瘤的MRI表现及鉴别分析

目的探讨颅内血管周细胞瘤(HPC)MR影像特点并与脑膜瘤影像表现进行对比分析。方法回顾性分析6例2015—2017年经中国医科大学附属第一医院确诊的HPC病人[年龄26～75岁,平均(46.33±16.88)岁]及40例颅内脑膜瘤病人[年龄27～78岁,平均(56.12±12.19)岁]的临床及影像资料。所有病人均进行MRI扫描检查,采用χ~2检验对2组病人的影像表现进行比较。结果 HPC与脑膜瘤病人MRI表现相似,常规MRI可表现为肿瘤分叶、瘤体内有囊变坏死、血管流空影、窄基底连接及骨质破坏,且HPC的发生率均高于脑膜瘤(P0.05)。但脑膜瘤增强MRI上脑膜尾征的发生率高于HPC(P0.05)。结论 HPC与脑膜瘤存在的影像差异有助于两者的鉴别诊断。     

MRI of the foot and ankle: prevalence and distribution of occult and palpable ganglia

The purpose of this study was to evaluate the prevalence and anatomic distribution of occult and palpable ganglia of the foot and ankle as seen by MRI. Within a 7-year period MRI of the ankle was performed on 2813 patients, and MRI of the foot on 2277 patients using a 1.5T magnet. In all, 167 ganglia in 155 patients were detected. MR images of these patients were reviewed retrospectively by two observers with regard to prevalence, imaging characteristics, and exact anatomic location of ganglia. Clinical findings and (when available) surgical reports were also reviewed. One hundred fifty-seven ganglia in 145 patients were present on MR images of the ankle, and 10 ganglia in 10 patients on MR images of the foot, resulting in a prevalence of 5.6% (157/2813) in the ankle, and a prevalence of 0.4% (10/2277) in the foot. The most common location was the tarsal sinus or tarsal canal (57/167 ganglia [34.1%]). However, only four of these (7%) were palpable as a soft-tissue mass. The second most common location was around the Lisfranc joint (23/167 [13.8%]), of which 11/23 [47.8%] were clinically palpable. Palpable ganglia were statistically larger in size than occult ganglia measured in any of three diameters (P = 0.01-0.002). In addition, ganglia of the foot and ankle represented 42% of all clinically suspected soft-tissue masses. Ganglia in the foot and ankle are an infrequent finding on routine MRI of the foot and ankle. When they occur, these ganglia are most frequently located in the tarsal sinus and tarsal canal, where they are occult to clinical palpation. If ganglia are clinically palpable, they are most commonly located around the Lisfranc joint. In addition, palpable ganglia are larger than occult ganglia.     

神经纤维瘤病Ⅰ型的头颈部CT和MRI表现

目的 探讨神经纤维瘤病Ⅰ型(NF-1)的CT和MRI表现.资料与方法 回顾性分析33例经病理证实的NF-1患者的临床资料及头颈部CT、MRI特征.结果 单侧听神经瘤2例;单侧视神经瘤1例及单发凸面脑膜瘤1例;视神经增粗4例;眼球体积增大伴外凸(青光眼)6例;脉络丛粗大钙化3例;面颊部肿块2例;颌面骨及周围改变6例;蝶翼缺损及颞叶疝21例,其他部位颅骨缺损8例;颈深部肿块2例.结论 CT与MRI相结合能全面显示NF-1的头颈部病变,对NF-1具有重要诊断价值.