among abundant image denoising methods proposed so far, the use of patchbased algorithms have attracted a lot of attention from image processingcommunity. although these methods are very powerful in presentation of highquality results, the impact of human visual system (hvs) is ignored in sole of them.in this paper the human visual geometry is used in preparation of a new method forimage denois...

one of the most common positioning errors in panoramic radiography is palatoglossal air space above the apices of the root of maxillary teeth. it causes a radiolucency obscuring the apices of maxillary teeth. in the case of this positioning error, the imaging should be repeated. this causes the patient be exposed to radiation again. to avoid the repetition of exposing harmful x-rays to the pati...

conclusions compared to iohexol and iopamidol, iodixanol use was associated with a lower patient perception of heat and lower hr while maintaining similar contrast-to-noise and signal-to-noise ratios. results baseline hr was similar across the patients assigned to iohexol, iopamidol, and iodixanol (65.3 ± 9.7, 66.9 ± 10.9, and 65.3 ± 13.3, respectively; p = ns). compared to iohexol and iopamido...

Background: Cone-beam computed tomography (CBCT) scanners for image-guided radiotherapy are in clinical use today, but there has been no consensus on uniform acceptance to verify the CBCT image quality yet. The present work proposed new methods to fully evaluate the performance of CBCT in its three-dimensional (3D) reconstruction space. Materials and Methods: Compared to the traditional methods...

background: electronic portal imaging devices (epids) play an important role in radiation therapy portal imaging, geometric and dosimetric verifications. a successful utilization of epids for imaging and dosimetric purposes requires a reliable quality control process routine to be carried out regularly. in this study, two in-house phantoms were developed and analyzed for implementation in a qua...

One of the most common positioning errors in panoramic radiography is palatoglossal air space above the apices of the root of maxillary teeth. It causes a radiolucency obscuring the apices of maxillary teeth. In the case of this positioning error, the imaging should be repeated. This causes the patient be exposed to radiation again. To avoid the repetition of exposing harmful X-rays to the pati...

This paper presents a new automatic image enhancement method by modifying the gamma value of its individual pixels. Most of existing gamma correction methods apply a uniform gamma value across the image. Considering the fact that gamma variation for a single image is actually nonlinear, the proposed method locally estimates the gamma values in an image using support vector machine. First, a dat...

Introduction: The purpose of this study is to investigate the effects of grid and non-grid techniques in the lateral cervical spine radiography on image quality and entrance surface dose (ESD). Although image quality and radiation doses have been studied by researchers, there is still a dearth of information on image quality and patient dose with different techniques. Material and Methods: The...

Introduction: The introduction of digital radiography has led to a significant problem in terms of dose creep. To address this problem, manufacturers have established a set of exposure indicators (EI) as a feedback mechanism to safeguard against overexposure. The EI is the measure of incident exposure to the detector that is directly proportional to the signal-to-noise...

Introduction: Filtering can greatly affect the quality of clinical images. Determining the best filter and the proper degree of smoothing can help to ensure the most accurate diagnosis. Methods: Forty five patient’s data aquired during brain phantom SPECT studies were reconstructed using filtered back-projection technique. The ramp, Shepp-Logan, Cosine, Hamming, Hanning, Butterworth, Metz...