Bone is a dynamic organ of the endoskeleton, playing an important role in structural integrity, mineral reservoirs, blood production, coagulation, and immunity. Metabolic bone disease encompasses a broad spectrum of inherited and acquired disorders that disrupt the normal homeostasis of bone formation and resorption. For patients affected by these processes, radiologic imaging plays a central role in diagnosis, monitoring treatment, and risk stratification. Radiologists should be familiar with the diseases, intimately aware of the imaging findings, and possessive of multimodality expertise to wisely guide the best practice of medicine. The purpose of this paper is to review the imaging features and characteristics of the most common types of metabolic bone disease with highlights of clinically relevant information so that readers can better generate appropriate differential diagnoses and recommendations. For this review, a thorough literature search for the most up-to-date information was performed on several key types of metabolic bone disease: osteoporosis, osteomalacia, rickets, scurvy, renal osteodystrophy, hyperparathyroidism, Paget's disease, osteogenesis imperfecta, acromegaly, and osteopetrosis. Although they all affect the bone, these diseases have both shared characteristic features that can be discerned through imaging.

The data are consistent with increased serum ChT activity not arising from altered macrophage lysosomal enzyme trafficking or GM-CSF-stimulated release of neutrophil granule stores. The association of ChT with age remains significant after controlling for neopterin and IL-6 changes with age, suggesting that ChT levels reflect a macrophage state distinct from acute macrophage activation or inflammatory state.

Linear CT measurements of left-sided chamber sizes correlate well with TTE. Right heart measurements and qualitative assessments agreed poorly with TTE.

1 In severe cases, it can progress to obstruction of the superior vena cava (SVC), pulmonary vessels, esophagus, or airways. Whereas SVC obstruction is relatively common, pulmonary artery (PA) involvement is less frequently encountered.2 Very few reports of long-term outcomes exist in the medical literature of either SVC or PA stents in this patient population. We discuss a case in which MF resulted in PA and SVC stenoses that were treated endovascularly, with early symptom improvement and 5-year survival with primary patency. Case ReportA 54-year-old man with histoplasmosis presented at our institution with worsening right-sided chest tightness and difficulty sleeping on his right side because of shortness of breath. Three years before this episode, he had developed SVC syndrome from progressive MF that we had successfully treated endovascularly with an SVC stent. Therefore, differential diagnosis for the current episode of dyspnea included restenosis of the SVC stent, pulmonary embolism, pneumonia, and pulmonary hypertension. A computed tomographic angiogram (CTA) revealed high-grade right-PA stenosis caused by continued progression of MF. In addition, imaging revealed near-complete occlusion of the truncus anterior to the right PA. Results of CTA also revealed that the SVC stent remained widely patent.Subsequently, we performed pulmonary arteriography to evaluate right-PA stenosis and PA hypertension, and to judge the possibility of intervention. Using a femoral approach, we advanced a Mott pulmonary catheter over the wire and into the right ventricle. The catheter was next advanced into the main PA, where the pressure was 35/12 mmHg, and then into the left PA-where digital subtraction arteriography revealed no abnormalities. The left main PA pressure was 36/10 mmHg. The catheter was then modified to make it more amenable to entering the stenosed right main PA. We used a 260-cm, modified stiff Glidewire ® (Terumo Medical Corporation; Somerset, NJ), advancing the wire and catheter into the right main PA. Digital subtraction arteriography revealed approximately 75% stenosis at the origin of the right main PA, extending distally 3.6 cm (Fig. 1). A pressure recording obtained distal to the obstruction was 11/5 mmHg (pressure gradient, 22 mmHg). Given the patient's symptoms, imaging findings, and pressure gradient, intervention was judged necessary.