In this paper the concept of molecular imaging is introduced, and its importance is addressed. Besides, the key points of molecular imaging are briefly reviewed from a view of engineering. Particular emphasis is given to the analysis of the function and the position of traditional medical imaging modalities in the era of molecular imaging. Finally a discussion is made for the further development of medical imaging modalities along the line of molecular imaging.
Diagnostic Imaging ; methods ; Molecular Imaging

Brain ; diagnostic imaging ; Diagnostic Imaging ; methods ; Humans ; Radiography ; Schizophrenia ; pathology

Thermoacoustic imaging (TAI) is a new non-invasive, non-ionization and nondestructive modality capable of high microwave contrast and high ultrasound resolution, and it has attracted extensive attention in recent years. This review introduces the technical principle, imaging system and imaging characteristics of TAI, and then introduces the application of TAI for breast cancer detection as an example. This review introduces the advantages of TAI in solving corresponding clinical problems in view of its high resolution and high contrast. In addition, it also explains the roles of TAI in medical diagnosis and treatment. Finally, the potential applications of TAI in medical diagnosis is introduced from many aspects and multiple perspectives. The future development of TAI in the challenges of current medical diagnosis is also prospected.
Acoustics ; Breast Neoplasms ; diagnostic imaging ; Diagnostic Imaging ; methods ; Humans ; Microwaves

OBJECTIVETo validate transient elastography (Fibroscan) in assessment of hepatic fibrosis in autoimmune hepatitis (AIH).

METHODSLiver stiffness was assessed using Fibroscan in totally 30 patients with AIH. We compared the results of Fibroscan with the Scheuer fibrosis stage in liver biopsy in each patient.

RESULTS4 patients were shown as liver fibrosis stage S0, 6 as S1, 5 as S2, 11 as S3 and 4 as S4. Failure of the Fibroscan measurement occurred in 1 case (3.3%) because of her increased body mass index (BMI). The stiffness of Fibroscan was significantly correlated with the liver biopsy fibrosis stage (r = 0.801, P less than 0.001). The liver stiffnesses between mild and moderate fibrosis (S0-2) and advanced fibrosis (S3-4) were significantly different (t = -3.937, P = 0.001).

CONCLUSIONTransient elastography (Fibroscan) is a promising non-invasive method for detection of fibrosis in patients with autoimmune hepatitis. Its use for the follow up and management of these patients and should be evaluated further.

The development of intravascular ultrasound (IVUS) techniques makes it possible to analyze the sectional information of the arteries and plaques. However, it can not precisely provide the biomechanical characterization of atheromas. The IVUS elastogram demonstrates tissue elasticity via estimating the axial stress-strain information of artery walls. With the help of such method, unstable lesions can be distinguished, the rupture inclination can be predicted, and the components of plaques are able to be classified. Compared with IVUS, elastogram is more objective. The constructing procedure and relative techniques as well as the preliminary clinical application, are reviewed in this article. The limitation at present and the probable future research direction are also mentioned.
Arteries ; diagnostic imaging ; Carotid Arteries ; diagnostic imaging ; Coronary Vessels ; diagnostic imaging ; Elasticity Imaging Techniques ; methods ; Femoral Artery ; diagnostic imaging

OBJECTIVETo discuss the clinical ultiliazation and significance of microembolus detection by transcranial Doppler (TCD) sonography in intracranial stenosis-occlusive disease.

DATA SOURCESAll related articles in this review were mainly searched from PubMed published in English from 1996 to 2012 using the terms of microembolic signal, transcranial Doppler, intracranial stenosis, stroke.

STUDY SELECTIONOriginal articles and reviews were selected if they were related to the clinical utilization of microembolus detection in intracranial stenosis-occlusive disease.

RESULTSIntracranial stenosis is a significant cause of cerebral emboli, and microembolus detection by TCD sonography were widely used in exploring the mechanisms of ischemic stroke with intracranial stenosis (including the middle cerebral artery stenosis and the vertebral-basilar stenosis), evaluating the prognosis of acute stroke, evaluating the therapeutic effects, and predicting the recurrent events of stroke.

CONCLUSIONMicroembolus detection by TCD sonography plays an important role in the cerebral ischemic stroke patients with intracranial stenosis.

Magnetic Particle Imaging (MPI) is a new medical imaging tool, which was born at the beginning of the 21st century. Compared with traditional imaging techniques, the preliminary research indicates that MPI shows higher sensitivity, resolution and imaging speed. This article presents the principle of MPI, its recent development from three different perspectives is introduced.
Diagnostic Imaging ; Magnetic Phenomena ; Magnetic Resonance Imaging ; methods ; Molecular Imaging

Advances in radionuclide tracers have allowed for more accurate imaging that reflects the actions of numerous neurotransmitters, energy metabolism utilization, inflammation, and pathological protein accumulation. All of these achievements in molecular brain imaging have broadened our understanding of brain function in Parkinson's disease (PD). The implementation of molecular imaging has supported more accurate PD diagnosis as well as assessment of therapeutic outcome and disease progression. Moreover, molecular imaging is well suited for the detection of preclinical or prodromal PD cases. Despite these advances, future frontiers of research in this area will focus on using multi-modalities combining positron emission tomography and magnetic resonance imaging along with causal modeling with complex algorithms.
Brain ; diagnostic imaging ; Humans ; Molecular Imaging ; methods ; trends ; Neuroimaging ; methods ; trends ; Parkinson Disease ; diagnostic imaging

Diagnostic Imaging ; methods ; Humans ; Liver Cirrhosis ; diagnosis

OBJECTIVEDeveloping a high-frequency ultrasonic skin imaging system to obtain the high resolution ultrasonic image of the skin. And further analyzing the ultrasonic images of skin to explore the imaging characteristics of skin structure and then explore the value of high-frequency imaging in the application of skin diagnosis.

METHODS50 MHz single element ultrasonic transducer, mechanic linear scanning method is used in the imaging system. The resolution and the ability of recognize the skin issue is verified by linear target scanning and clinical trials.

RESULTSBoth the axial and lateral resolution of the system reaches 50 microm. The subtle structure of normal skin tissue is clearly visible. Some diseases have obvious appearance in the image.

CONCLUSIONS50 MHz ultrasonic skin imaging system is of high resolution and is valuable to skin structure detect and disease diagnosis.