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At least 343 records · Page 19Linked to original sources
PubMed2005

A laboratory comparison of three imaging systems for image quality and radiation exposure characteristics.

AIM: To measure and compare the relationships between image quality and X-ray exposure for three types of intraoral imaging system (conventional film, phosphor plate system and CCD-based system). METHODOLOGY: Kodak 'Insight' F-speed film, Digora FMX (phosphor plate system) and Visualix USB (CCD system) were used to produce series of radiographic images of two tooth-bearing jaw specimens (maxillary molar and mandibular molar regions) at a range of X-ray exposures from 10 ms to 2000 ms (all at 6 mA and 60 kV). Digital images were viewed from a computer monitor and films viewed on a conventional light box. Five observers scored each image using a five-point subjective image quality scale (0-4). RESULTS: Optimum image quality (4) was seen for conventional film. Neither digital system achieved this score at any exposure, achieving in both cases a maximum mean score of 3.1 (adequate visualization). The two digital systems, however, provided adequate visualization at substantially lower exposure times. Dose reduction over conventional film for maximum quality images with Visualix USB was 20%, but for Digora FMX it was 70%. All three systems gave acceptable (quality score of two or higher) images over a broad range of exposures. CONCLUSIONS: In terms of subjective image quality, F-speed film performed better than the two digital systems, but this must be weighed against the ability of the two digital systems to give adequate image quality at lower radiation doses.

Humans↗
PubMedDate not supplied

Three-beam K-edge imaging of iodine using differences between fluoroscopic video images: experimental results.

In an earlier article we discussed the rationale for using differences between video images in three-beam selective iodine K-edge imaging. Rather than combining three initial images Li linearly to yield the final image k1L1 + k2L2 + k3L3, differences between the Li were first generated and then combined either to linear or quadratic order. This approach was motivated by the desire to suppress the large multiplicative biases of fluoroscopic imaging and justified by theoretically proving that k1 + k2 + k3 is approximately equal to 0. In this paper we discuss the instrumentation and experimental results obtained from this difference-based technique. A specially-constructed apparatus is described which automatically selects the optimum combination coefficients and combines the difference images up to quadratic order at realtime video rates. Three methods for generating K-edge subtraction images are compared: the former approach in which the Li are linearly combined and combination of differences to linear and quadratic order. In imaging phantoms in which the iodine distribution is known, the resultant subtraction images from all three methods appear similar. Inspection of signal sizes shows that the quadratic difference-based approach provides superior bone and tissue residual suppression by about a factor of 2. In imaging phantoms in which the iodine distribution is unknown, incomplete suppression of x-ray scatter and image intensifier veiling glare prevent a quantitative comparison of performance of the three algorithms. An experiment verification is provided of the theorem which states that k1 + k2 + k3 is approximately equal to 0.

Fluoroscopy↗
PubMedDate not supplied

The k-trajectory formulation of the NMR imaging process with applications in analysis and synthesis of imaging methods.

The fundamental operations of nuclear magnetic resonance (NMR) imaging can be formulated, for a large number of methods, as sampling the object distribution in the Fourier spatial-frequency domain, followed by processing the digitized data (often simply by Fourier transformation) to produce a digital image. In these methods, which include reconstruction from projections, Fourier imaging, spin-warp imaging, and echo-planar imaging, controllable gradient fields determine the points in the spatial-frequency domain which are sampled at any given time during the acquisition of data (the free induction decay, or FID). The detailed time dependence of the resulting trajectory of sample points (the k trajectory) determines the relative weight and accuracy with which image information at each spatial frequency is measured, establishing theoretical limitations on image quality achievable with a given imaging method. We demonstrate here that these considerations may be used to compare the theoretical capabilities of NMR imaging methods, and to derive new imaging methods with optimal theoretical imaging properties.

Image Enhancement↗
PubMed1994

Value of phase-shift gradient-echo MR imaging in the differentiation of pelvic lesions with high signal intensity at T1-weighted imaging.

PURPOSE: To assess the value of phase-shift gradient-echo magnetic resonance (MR) imaging with the fast low-angle shot (FLASH) technique in the differentiation of hemorrhagic tumors and teratomas. MATERIALS AND METHODS: T1- and T2-weighted spin-echo imaging and phase-shift MR imaging were performed in 60 patients. On T1-weighted images, the signal intensity of lesions was compared with that of intraperitoneal fat. Findings at MR imaging were compared with the surgical findings. The diagnostic performance of each pulse sequence was analyzed with receiver operating characteristic curves. RESULTS: Sixty high-signal-intensity lesions were identified in 45 patients at T1-weighted imaging. Hemorrhagic lesions and teratomas had similar signal intensities on both T1- and T2-weighted images. Lesions were detected more decisively with FLASH imaging than with T1- and T2-weighted imaging. CONCLUSIONS: Phase-shift gradient-echo imaging is a readily available method for the differential diagnosis of lesions with high signal intensity at T1-weighted MR imaging.

Adolescent↗
PubMed1999

Extrahepatic abdominal imaging in patients with malignancy: comparison of MR imaging and helical CT, with subsequent surgical correlation.

PURPOSE: To compare state-of-the-art magnetic resonance (MR) imaging with single-phase helical computed tomography (CT) in abdominal screening for extrahepatic disease in patients with proved malignancy. MATERIALS AND METHODS: Fifty-seven patients with known malignancy underwent abdominal contrast material-enhanced helical CT and MR imaging from 1994 through 1997. Prospective interpretations of CT scans and MR images were used to assess each modality's sensitivity in depicting malignant extrahepatic tumor at 17 anatomic sites. Imaging findings were compared with surgical results in all patients. RESULTS: Helical CT depicted 101 (66%) of 154 surgically confirmed extrahepatic tumor sites; MR imaging depicted 139 (90%) (P < .001). MR imaging depicted tumor in more patients at 11 of the 17 anatomic sites; at six sites, MR imaging and helical CT were equivalent. MR imaging showed significantly greater depiction of extrahepatic tumor for the peritoneum (P < .05), bowel (P < .01), and mesentery (P < .05). False-negative interpretations would have altered patient care had the extrahepatic tumor remained undetected in 13 patients for helical CT and in six patients for MR imaging. CONCLUSION: State-of-the-art MR imaging can be used for effective abdominal screening for extrahepatic tumor in patients with malignancy. Compared with single-phase helical CT, MR imaging depicted more sites of extrahepatic tumor and was particularly advantageous for the peritoneum, mesentery, and bowel.

Abdominal Neoplasms↗
PubMed2001

MR imaging--guided large-core (14-gauge) needle biopsy of small lesions visible at breast MR imaging alone.

PURPOSE: To report our experience with magnetic resonance (MR) imaging-guided large-core breast biopsy of lesions visible at breast MR imaging only. MATERIALS AND METHODS: Stereotactic large-core (14-gauge) needle biopsy of 78 lesions visible at MR imaging only was performed with MR imaging guidance in 59 patients. Results were validated with excisional biopsy or mastectomy in 42 lesions and with radiologic-pathologic correlation and/or follow-up MR imaging for at least 2 years in another 17 lesions. The accuracy of MR imaging--guided core biopsy was determined for those 59 lesions with established validation. The effect on patient treatment was evaluated by comparing the prebiopsy treatment plan with the ultimate treatment. RESULTS: Histologic diagnosis from core biopsy was possible in 77 (99%) of 78 lesions. In the 59 lesions with established validation, the diagnostic accuracy of MR imaging--guided core biopsy was 98% (58 of 59). Successful MR imaging--guided core biopsy findings changed treatment in 70% (54 of 77) of lesions. Difficulties were due to the unsatisfactory performance of earlier types of MR imaging--compatible biopsy guns and decreasing target visibility during intervention. CONCLUSION: MR imaging--guided large-core stereotactic breast biopsy is sufficiently accurate for obtaining histologic proof of lesions visible only at MR imaging. It can change patient treatment by reducing unnecessary surgical biopsy and can enable one-step surgery for breast cancers.

Adult↗
PubMed1995

Magnetic resonance imaging in the detection of focal liver lesions: comparison of dynamic contrast-enhanced TurboFLASH and T2 weighted spin echo images.

In a previous study using dynamic contrast-enhanced TurboFLASH (DCETF) for demonstration of the portal venous system we found that this technique showed more liver lesions than T2 weighted spin echo (T2WSE) imaging in the same patients. In this study we have formally compared axial T2WSE images (TR 2000, TE 45/90) with TurboFLASH images (TR 135, TE 4, FA 80 degrees) acquired immediately after bolus injection of Gd-DTPA (0.1 mmol kg-1) in 41 patients referred for hepatic magnetic resonance imaging (MRI) prior to surgery for liver lesions. The images of each sequence were independently reviewed by two observers. The lesions were counted and each sequence was scored for conspicuity, level of artefact and subjective image quality. Contrast-to-noise ratios using user defined regions of interest were calculated. Significantly more lesions were seen on DCETF (n = 186) images than on T2WSE (n = 123) images (p < 0.001). Lesion conspicuity was equal in 53% of cases, better on DCETF in 36% and better on T2WSE in 11%. Contrast-to-noise ratios were significantly higher on DCETF images (p < 0.05). DCETF imaging provided a substantial improvement in lesion detection compared with T2WSE imaging.

Adult↗
PubMed1997

Imaging of puerperal septic thrombophlebitis: prospective comparison of MR imaging, CT, and sonography.

OBJECTIVE: Our objective was to compare prospectively the abilities of MR imaging, CT, and sonography to reveal puerperal septic thrombophlebitis in the pelvis. SUBJECTS AND METHODS: Seventy-six women with puerperal fever for 5 days refractory to antimicrobial therapy underwent MR imaging, CT, and sonography. We obtained unenhanced axial CT images followed by enhanced images after the administration of an oral contrast agent for which we followed a specific protocol. Axial T1- and T2-weighted spin-echo MR images with phase reconstruction and sagittal T1-weighted MR images were obtained. Real-time sonography was performed using Doppler color flow mapping and spectral waveform analysis. RESULTS: Of the 76 women, 64 completed studies with all three techniques. Ovarian vein thrombosis was diagnosed in 12 women. True-positive results were indicated when at least two of the three studies showed the presence of a clot; true-negative results were indicated when at least two of the three studies showed a lack of thrombosis. MR imaging and CT revealed both ovarian veins in all cases (64/64). Sonography revealed 33 (52%) of 64 right ovarian veins and 15 (23%) of 64 left ovarian veins. MR imaging (sensitivity, 92%; specificity, 100%) and CT (sensitivity, 100%; specificity 99%) were comparable in all but two cases. In one such case, MR imaging showed patency, CT revealed findings interpreted as thrombosis, and sonography showed flow in the partially occluded vein. In the second such case, bilateral thrombosis was seen on CT, but interpretations based on sonography and MR imaging were left-sided thrombosis only. Sonography correctly revealed six of the 12 cases of ovarian vein thrombosis. CONCLUSION: CT and MR imaging proved to be the studies of choice in the evaluation of ovarian vein thrombosis.

Adult↗
PubMed2001

MR imaging as the sole preoperative imaging modality for right hepatectomy: a prospective study of living adult-to-adult liver donor candidates.

OBJECTIVE: Our aim was to investigate the feasibility of MR imaging as a comprehensive preoperative imaging test for examination of liver donor candidates for adult-to-adult right lobe transplantation. SUBJECTS AND METHODS: Twenty-five consecutive donor candidates were examined at 1.5 T using a torso phased array coil with breath-hold T1- and T2-weighted imaging of the abdomen, MR cholangiography using T2-weighted turbo spin-echo imaging, and MR angiography and venography of the liver using two interpolated three-dimensional spoiled gradient-echo sequences (average dose of gadolinium contrast material, 0.17 mmol/kg). Images were interpreted for liver parenchymal and extrahepatic abnormalities; measurements of right and left lobe liver volumes; definition of hepatic arterial, portal venous, and hepatic venous anatomy; and definition of the biliary branching pattern. Findings were compared with those of conventional angiography in 13 patients, 11 of whom also had surgical findings for comparison. RESULTS: Nine patients were excluded as candidates for donation on the basis of MR imaging findings that included parenchymal or extrahepatic abnormalities in five patients, vascular anomalies in two, and biliary anomalies in three. Two patients who did not undergo surgery underwent conventional angiography that confirmed MR angiographic findings except for a small (<2 mm) accessory left hepatic artery missed on MR imaging. Of the nine patients who underwent successful right hepatectomy, all MR imaging findings were corroborated intraoperatively. In two patients, right hepatectomy was aborted at laparotomy because of intraoperative cholangiography findings; in one of them, the biliary finding was unsuspected on MR imaging. CONCLUSION: A comprehensive MR imaging examination has the potential to serve as the sole preoperative imaging modality for living adult-to-adult liver donor candidates provided improvements in definition of intrahepatic biliary anatomy can be achieved.

Adult↗
PubMed1995

Quantitative description of echographic images of morphea plaques as assessed by computerized image analysis on 20 MHz B-scan recordings.

In order to find image descriptors enabling the characterization of sclerotic skin of morphea plaques and their objective differentiation from normal skin, we studied 52 lesions in 35 patients affected by plaque type morphea. Echographic evaluations were carried out using a 20 MHz B-scanner, providing cross-sectional images of the skin. Images were processed by a program providing a numerical representation of the picture data, based on the following parameters, which were considered for 7 different amplitude intervals: 1) the extension of image areas marked by amplitude bands of interest, 2) the percentage of the image surface reflecting within a homogeneous amplitude band, 3) the number of objects composing the image, 4) the average object size, and 5) the "density" of the objects. For all parameters considered, marked differences between sclerotic skin and normal tissue were observable. When assessment is performed with amplitude bands covering the lower part of the scale, the image referring to sclerotic tissue appears relatively homogeneous with few, large objects within a thickened skin block, which occupy a more extended image surface in comparison to images of normal skin, characterized by spots, which are small and closely packed. On the contrary, binary images of morphea plaques transformed by intermediate to high amplitude intervals appear with fewer objects of approximately the same size or smaller, which are less compressed in respect to healthy skin images.

Adult↗
PubMed2004

[Studies on digital watermark embedding intensity against image processing and image deterioration].

In order to apply digital watermarking to medical imaging, it is required to find a trade-off between strength of watermark embedding and deterioration of image quality. In this study, watermarks were embedded in 4 types of modality images to determine the correlation among the watermarking strength, robustness against image processing, and image deterioration due to embedding. The results demonstrated that watermarks which were embedded by the least significant bit insertion method became unable to be detected and recognized on image processing even if the watermarks were embedded with such strength that could cause image deterioration. On the other hand, watermarks embedded by the Discrete Cosine Transform were clearly detected and recognized even after image processing regardless of the embedding strength. The maximum level of embedding strength that will not affect diagnosis differed depending on the type of modality. It is expected that embedding the patient information together with the facility information as watermarks will help maintain the patient information, prevent mix-ups of the images, and identify the test performing facilities. The concurrent use of watermarking less resistant to image processing makes it possible to detect whether any image processing has been performed or not.

Humans↗
PubMed1992

Imaging of the hip joint. Computed tomography versus magnetic resonance imaging.

The authors reviewed the applications and limitations of computed tomography (CT) and magnetic resonance (MR) imaging in the assessment of the most common hip disorders. Magnetic resonance imaging is the most sensitive technique in detecting osteonecrosis of the femoral head. Magnetic resonance reflects the histologic changes associated with osteonecrosis very well, which may ultimately help to improve staging. Computed tomography can more accurately identify subchondral fractures than MR imaging and thus remains important for staging. In congenital dysplasia of the hip, the position of the nonossified femoral head in children less than six months of age can only be inferred by indirect signs on CT. Magnetic resonance imaging demonstrates the cartilaginous femoral head directly without ionizing radiation. Computed tomography remains the imaging modality of choice for evaluating fractures of the hip joint. In some patients, MR imaging demonstrates the fracture even when it is not apparent on radiography. In neoplasm, CT provides better assessment of calcification, ossification, and periosteal reaction than MR imaging. Magnetic resonance imaging, however, represents the most accurate imaging modality for evaluating intramedullary and soft-tissue extent of the tumor and identifying involvement of neurovascular bundles. Magnetic resonance imaging can also be used to monitor response to chemotherapy. In osteoarthrosis and rheumatoid arthritis of the hip, both CT and MR provide more detailed assessment of the severity of disease than conventional radiography because of their tomographic nature. Magnetic resonance imaging is unique in evaluating cartilage degeneration and loss, and in demonstrating soft-tissue alterations such as inflammatory synovial proliferation.

Arthritis↗
PubMed1988

[Flow imaging of the cardiovascular system using magnetic resonance imaging].

Blood flow images by magnetic resonance imaging (MRI) using a 0.25 T unit were evaluated for nine normal volunteers and 108 subjects with a variety of cardiovascular abnormalities. Using the non-gated short-spin echo (SE) technique, blood flow in the cardiovascular systems was not imaged in the normal volunteers. Using end-systolic and end-diastolic SE techniques for the normal subjects, blood flow in the cardiac chambers was not clearly imaged. Blood flow in the ascending aorta and aotric arch often did not appear in the gated SE images of the normal subjects. However, blood flow in the descending aorta was often observed in the gated SE images. Blood flow imaging was demonstrated by both non-gated and gated SE techniques in regions where blood flow was relatively slow; for example, in the left atrium of mitral stenosis, in an aortic aneurysm, in a false lumen of an aortic dissection, and in the left ventricle having old myocardial infarction. Using the non-gated inversion recovery (IR) technique, no blood flow was imaged in the cardiovascular system except in the left atrium of one case with mitral stenosis. Using the non-gated short SE technique, there was good correlation between the thrombus formation and the presence of blood flow images in the left atria of 17 patients with mitral stenosis, and in the aneurysmal portions of the aorta or in the false lumens of aortic dissection of 18 patients. It was suggested that mural thrombi in such diseases were related to the relatively slow blood flow. Blood flow imaging easily distinguished stagnant blood flow from mural thrombi using non-gated short SE, end-systolic SE, and IR techniques. Thus, blood flow imaging using MRI should become an important means of evaluating the cardiovascular system.

Adult↗
PubMed2005

Partially parallel imaging with phase-sensitive data: Increased temporal resolution for magnetic resonance temperature imaging.

Magnetic resonance temperature imaging can be used to monitor the progress of thermal ablation therapies, increasing treatment efficacy and improving patient safety. High temporal resolution is important when therapies rapidly heat tissue, but many approaches to faster image acquisition compromise image resolution, slice coverage, or phase sensitivity. Partially parallel imaging techniques offer the potential for improved temporal resolution without forcing such concessions. Although these techniques perturb image phase, relative phase changes between dynamically acquired phase-sensitive images, such as those acquired for MR temperature imaging, can be reliably measured through partially parallel imaging techniques using reconstruction filters that remain constant across the series. Partially parallel and non-accelerated phase-difference-sensitive data can be obtained through arrays of surface coils using this method. Average phase differences measured through partially parallel and fully Fourier encoded images are virtually identical, while phase noise increases with g(sqrt)L as in standard partially parallel image acquisitions..

Animals↗
PubMed2000

Imaging of heterogeneous materials with a turbo spin echo single-point imaging technique.

A magnetic resonance imaging method is presented for imaging of heterogeneous broad linewidth materials. This method allows for distortionless relaxation weighted imaging by obtaining multiple phase encoded k-space data points with each RF excitation pulse train. The use of this method, turbo spin echo single-point imaging-(turboSPI), leads to decreased imaging times compared to traditional constant-time imaging techniques, as well as the ability to introduce spin-spin relaxation contrast through the use of longer effective echo times. Imaging times in turboSPI are further decreased through the use of low flip angle steady-state excitation. Two-dimensional images of paramagnetic doped agarose phantoms were obtained, demonstrating the contrast and resolution characteristics of the sequence, and a method for both amplitude and phase deconvolution was demonstrated for use in high-resolution turboSPI imaging. Three-dimensional images of a partially water-saturated porous volcanic aggregate (T(2L) approximately 200 ms, Deltanu(1/2) approximately 2500 Hz) contained in a hardened white Portland cement matrix (T(2L) approximately 0.5 ms, Deltanu(1/2) approximately 2500 Hz) and a water-saturated quartz sand (T(2) approximately 300 ms, T(2)(*) approximately 800 microseconds) are shown.

Copper Sulfate↗
PubMed2004

Evaluation of atlas selection strategies for atlas-based image segmentation with application to confocal microscopy images of bee brains.

This paper evaluates strategies for atlas selection in atlas-based segmentation of three-dimensional biomedical images. Segmentation by intensity-based nonrigid registration to atlas images is applied to confocal microscopy images acquired from the brains of 20 bees. This paper evaluates and compares four different approaches for atlas image selection: registration to an individual atlas image (IND), registration to an average-shape atlas image (AVG), registration to the most similar image from a database of individual atlas images (SIM), and registration to all images from a database of individual atlas images with subsequent multi-classifier decision fusion (MUL). The MUL strategy is a novel application of multi-classifier techniques, which are common in pattern recognition, to atlas-based segmentation. For each atlas selection strategy, the segmentation performance of the algorithm was quantified by the similarity index (SI) between the automatic segmentation result and a manually generated gold standard. The best segmentation accuracy was achieved using the MUL paradigm, which resulted in a mean similarity index value between manual and automatic segmentation of 0.86 (AVG, 0.84; SIM, 0.82; IND, 0.81). The superiority of the MUL strategy over the other three methods is statistically significant (two-sided paired t test, P < 0.001). Both the MUL and AVG strategies performed better than the best possible SIM and IND strategies with optimal a posteriori atlas selection (mean similarity index for optimal SIM, 0.83; for optimal IND, 0.81). Our findings show that atlas selection is an important issue in atlas-based segmentation and that, in particular, multi-classifier techniques can substantially increase the segmentation accuracy.

Algorithms↗
PubMed2006

High frame rate imaging system for limited diffraction array beam imaging with square-wave aperture weightings.

A general-purpose high frame rate (HFR) medical imaging system has been developed. This system has 128 independent linear transmitters, each of which is capable of producing an arbitrary broadband (about 0.05-10 MHz) waveform of up to +/- 144 V peak voltage on a 75-ohm resistive load using a 12-bit/40-MHz digital-to-analog converter. The system also has 128 independent, broadband (about 0.25-10 MHz), and time-variable-gain receiver channels, each of which has a 12-bit/40-MHz analog-to-digital converter and up to 512 MB of memory. The system is controlled by a personal computer (PC), and radio frequency echo data of each channel are transferred to the same PC via a standard USB 2.0 port for image reconstructions. Using the HFR imaging system, we have developed a new limited-diffraction array beam imaging method with square-wave aperture voltage weightings. With this method, in principle, only one or two transmitters are required to excite a fully populated two-dimensional (2-D) array transducer to achieve an equivalent dynamic focusing in both transmission and reception to reconstruct a high-quality three-dimensional image without the need of the time delays of traditional beam focusing and steering, potentially simplifying the transmitter subsystem of an imager. To validate the method, for simplicity, 2-D imaging experiments were performed using the system. In the in vitro experiment, a custom-made, 128-element, 0.32-mm pitch, 3.5-MHz center frequency linear array transducer with about 50% fractional bandwidth was used to reconstruct images of an ATS 539 tissue-mimicking phantom at an axial distance of 130 mm with a field of view of more than 90 degrees. In the in vivo experiment of a human heart, images with a field of view of more than 90 degrees at 120-mm axial distance were obtained with a 128-element, 2.5-MHz center frequency, 0.15-mm pitch Acuson V2 phased array. To ensure that the system was operated under the limits set by the U.S. Food and Drug Administration, the mechanical index, thermal index, and acoustic output were measured. Results show that higher-quality images can be reconstructed with the square-wave aperture weighting method due to an increased penetration depth as compared to the exact weighting method developed previously, and a frame rate of 486 per second was achieved at a pulse repetition frequency of about 5348 Hz for the human heart.

Computer Systems↗
PubMed1993

Echo-planar imaging of the liver with a standard MR imaging system.

PURPOSE: A multisection, whole-body echo-planar imaging (EPI) sequence was developed to obtain T2-weighted images of the liver in one 18-second breath hold with a standard magnetic resonance (MR) imaging system. MATERIALS AND METHODS: This capability was achieved by dividing the data acquisition period into eight interleaved segments rather than one or two as implemented previously with EPI systems having high-power gradient subsystems. RESULTS: The interleaved echo-planar images had excellent depiction of anatomy and no identifiable respiratory artifact. In 26 lesions in 12 patients, the eight-shot echo-planar images (2,000/66 [repetition time msec/echo time msec]) had superior contrast compared with conventional T2-weighted spin-echo (SE) images (2,500/60) by an average factor of 1.22 +/- 0.31 (standard deviation) and an average contrast-to-noise ratio relative to conventional T2-weighted SE images of 0.85 +/- 0.22. CONCLUSION: With a conventional MR imaging system, breath-hold T2-weighted echo-planar images of the liver are comparable in diagnostic quality to conventional T2-weighted SE images.

Adenoma, Islet Cell↗