Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “pathological image”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources

Riedel's thyroiditis: clinical, pathological and imaging features.

Riedel's thyroiditis (RT) is an extremely rare form of chronic thyroiditis, characterised by a fibroinflammatory process which partially destroys the thyroid, often involving surrounding tissues. We describe an unusual case of RT in a 38-year-old woman, and discuss its typical clinical, pathological, ultrasound, radionuclide scanning and magnetic resonance findings. We conclude that the diagnosis of RT is highly suggestive in the presence of a hard gland (or nodule), fixed to adjacent structures; 'cold' on Tc99 scan; hypoechoic with absence of vascular flow, invading the adjacent neck structures on ultrasound; hypointense in T1- and T2-weighted MR images; and showing fibrous tissue fragments with inflammatory cells at cytological examination. Thyroidectomy has to be performed to confirm the diagnosis and to relieve pressure symptoms.

Adult↗

Normal and pathological NCAT image and phantom data based on physiologically realistic left ventricle finite-element models.

The four-dimensional (4-D) NURBS-based cardiac-torso (NCAT) phantom, which provides a realistic model of the normal human anatomy and cardiac and respiratory motions, is used in medical imaging research to evaluate and improve imaging devices and techniques, especially dynamic cardiac applications. One limitation of the phantom is that it lacks the ability to accurately simulate altered functions of the heart that result from cardiac pathologies such as coronary artery disease (CAD). The goal of this work was to enhance the 4-D NCAT phantom by incorporating a physiologically based, finite-element (FE) mechanical model of the left ventricle (LV) to simulate both normal and abnormal cardiac motions. The geometry of the FE mechanical model was based on gated high-resolution X-ray multislice computed tomography (MSCT) data of a healthy male subject. The myocardial wall was represented as a transversely isotropic hyperelastic material, with the fiber angle varying from -90 degrees at the epicardial surface, through 0 degrees at the midwall, to 90 degrees at the endocardial surface. A time-varying elastance model was used to simulate fiber contraction, and physiological intraventricular systolic pressure-time curves were applied to simulate the cardiac motion over the entire cardiac cycle. To demonstrate the ability of the FE mechanical model to accurately simulate the normal cardiac motion as well as the abnormal motions indicative of CAD, a normal case and two pathologic cases were simulated and analyzed. In the first pathologic model, a subendocardial anterior ischemic region was defined. A second model was created with a transmural ischemic region defined in the same location. The FE-based deformations were incorporated into the 4-D NCAT cardiac model through the control points that define the cardiac structures in the phantom which were set to move according to the predictions of the mechanical model. A simulation study was performed using the FE-NCAT combination to investigate how the differences in contractile function between the subendocardial and transmural infarcts manifest themselves in myocardial Single photon emission computed tomography (SPECT) images. The normal FE model produced strain distributions that were consistent with those reported in the literature and a motion consistent with that defined in the normal 4-D NCAT beating heart model based on tagged magnetic resonance imaging (MRI) data. The addition of a subendocardial ischemic region changed the average transmural circumferential strain from a contractile value of -0.09 to a tensile value of 0.02. The addition of a transmural ischemic region changed average circumferential strain to a value of 0.13, which is consistent with data reported in the literature. Model results demonstrated differences in contractile function between subendocardial and transmural infarcts and how these differences in function are documented in simulated myocardial SPECT images produced using the 4-D NCAT phantom. Compared with the original NCAT beating heart model, the FE mechanical model produced a more accurate simulation for the cardiac motion abnormalities. Such a model, when incorporated into the 4-D NCAT phantom, has great potential for use in cardiac imaging research. With its enhanced physiologically based cardiac model, the 4-D NCAT phantom can be used to simulate realistic, predictive imaging data of a patient population with varying whole-body anatomy and with varying healthy and diseased states of the heart that will provide a known truth from which to evaluate and improve existing and emerging 4-D imaging techniques used in the diagnosis of cardiac disease.

Algorithms↗

Neurilemoma of the renal capsule: MR imaging and pathologic correlation.

We report a case of neurilemoma arising from the renal capsule. Renal neurilemoma is an especially rare tumor, with only 15 cases previously reported. We attempted to correlate MR findings with microscopic components of the tumor. On T2-weighted images the solid part of the tumor was heterogeneous hyperintense. The MR signal intensity on T2-weighted images help estimate microscopic components of the renal neurilemoma.

Aged↗

Results of a prospective study with comparison of clinical, endosonographic, computed tomography, magnetic resonance imaging and pathologic staging of advanced gynecologic carcinoma and recurrence.

Between January 1988 and April 1991, 57 patients with advanced gynecologic carcinoma were preoperatively evaluated by gynecologic examination and endosonography (ESG) using general anesthesia. Abdominopelvic computed tomography (CT) was performed in 49 patients and magnetic resonance imaging (MRI) in 21 patients. There were 34 primary tumors and 23 instances of recurrence. Causes of gynecologic carcinoma were 38 carcinomas of the cervix uteri (26 primary and 12 recurrences), eight carcinomas of the ovary (four primary and four recurrences), three recurrences of carcinoma of the endometrium, five sarcomas of the uterus (one primary and four recurrences) and three primary carcinomas of the vagina. All of the patients were operated upon. This perspective study compares the data from clinical and imaging examinations to the data obtained from histologic examination of surgical sections. According to anterior or posterior tumor extension, the accuracy of clinical evaluation and preoperative imaging were studied for the posterior vesical wall and the vesicovaginal septum and the anterior rectal wall and the rectovaginal septum. Histologic examination revealed vesical involvement in 17 patients and of the involvement of vesicovaginal septum in 21 patients. The accuracy of the clinical examination, ESG, cystoscopy, CT and MRI was 83, 88, 87, 75 and 81 percent, respectively, for vesical extension. Cystoscopy was not taken into account for evaluation of extension to the vesicovaginal septum--accuracy was 80, 90, 67 and 86 percent for clinical examination, ESG, CT and MRI. Histologic examination showed involvement in the rectum in 14 patients and involvement in the rectovaginal septum in 19 patients. Rectoscopy was performed 13 times. The accuracy of clinical examination, ESG, CT and MRI was 91, 98, 89 and 71 percent, respectively, for extension to the anterior rectal wall. Rectoscopy was not taken into account for evaluation of extension to the rectovaginal septum--accuracy was 80, 96, 75 and 57 percent for clinical examination, ESG, CT and MRI. Endosonography would seem to be useful to complete examinations for regional extension of advanced gynecologic carcinomas. Its accuracy is superior to that of other examinations. Because it is performed using general anesthesia, there is no discomfort for the patient during this low cost procedure.

Cystoscopy↗

[Imaging and pathological studies on the esophageal dysfunction in patients with myotonic dystrophy].

The purpose of this study is to clarify a correlation between the esophageal dysfunction and suffocation after meals in patients with myotonic dystrophy (MD) and to find how to prevent such accidents. Using imaging methods, we examined eight patients with MD (six of them had difficulty in swallowing), four patients with other neuromuscular diseases (Fukuyama-type congenital muscular dystrophy, congenital myopathy, Machado-Joseph disease, and Duchenne's muscular dystrophy), and two healthy control subjects. We also investigated material from an autopsy of another patient with MD who died of suffocation. In all patients with MD, fluoroscopy and computed tomography showed dilatation of the esophagus, particularly in the proximal third, and residual contrast media in the esophagus 15 to 40 minutes after swallowing. In histologic studies, morphologic changes were confined to the esophageal striated muscle in a patient with MD. These results indicate that regurgitation from the esophagus to the trachea happens more than 40 minutes after swallowing in patients with MD and that histological alterations of striated muscle are primary causes of the esophageal dysfunction. From these findings, we propose that patients with MD should not lie down at least 40 minutes after meals whether they complain of difficulty in swallowing or not.

Adolescent↗

[Certain patterns in the formation of optical illusions].

A structural dynamic analysis of productive disorders in visual perception was attempted on the basis of psychological study of 344 patients. These disorders were studied according to the increasing degree of inadequacy (anisomorphia) of pathological images in respect to real stimula. Considering the differences of such phenomena according to the degree of discrepancy of their perceptive characteristics with the traits of real objects, some successively complicated pathological images were examined, including traditional false recognition, illusions and hallucinations, as well as interlapping intermediate structures. Some pathogenetical mechanisms in the formations of visual illusions are suggested. Clinico-psychopathological parallels are made between disorders of visual perception and disease entities.

Dementia↗

Soft tissue signal abnormality associated with eosinophilic granuloma. Correlation of MR imaging with pathologic findings.

Six patients with eosinophilic granuloma were studied retrospectively in order to correlate the MRI appearances with the pathology. Ages ranged from 2 years 6 months to 11 years. The bones involved were the humerus, ulna, radius, femur, clavicle and ilium. Plain films, MRI and pathology specimens were obtained. A lytic lesion with indistinct margins, endosteal erosions and periosteal reaction was seen in all cases on plain radiographs. Bone marrow signal was decreased on T1-weighted images and increased on T2-weighted images throughout the bony lesion in all cases. T2-weighted images showed extensive soft-tissue abnormalities suggesting inflammatory changes in four cases. In two cases abnormalities were limited. Extensive changes correlated histologically with an early phase lesion. Localized minor changes were associated with a mid-phase lesion. Inflammatory soft-tissue changes could be associated with eosinophilic granuloma. The size of the soft tissue mass correlated well with the activity of the bony lesion.

Bone and Bones↗

Computed tomography, magnetic resonance imaging and pathological correlations in a case of Binswanger's disease.

The results of 3 computed tomography (CT) examinations carried out over a 7 year period and of a post-mortem magnetic resonance (MR) study showed aspects of a white matter disease in a hypertensive patient suffering from vascular dementia. Histopathology revealed the primary cause of dementia to be a white matter degeneration sparing the U fibers. Rarefaction of both the myelin sheaths and the axons was present together with severe thickening of the medullary arteries. These findings support the existence of Binswanger's disease (BD) as a distinct variety of arteriosclerotic dementia. CT and MR imaging are valuable aids for diagnosis. However, since there are many other causes of CT and MR demonstrated diffuse white matter degeneration in the elderly, a conclusive diagnosis of BD requires pathological confirmation.

Dementia, Vascular↗

Imaging of peritoneal pathology.

Advances in the imaging of peritoneal pathology are reviewed. Papers published in the past year in the radiologic, surgical, and pediatric literature discussed the detection, quantification, characterization, and management of fluid collections in the trauma patient or the patient with intra-abdominal sepsis; the assessment of various imaging modalities in the evaluation of unexplained fever or pain; and the detection, characterization, and localization of primary, recurrent, or metastatic abdominal neoplasms.

Diagnostic Imaging↗

Hepatic parenchymal changes after ethanol injection in rabbits: correlation of conventional and dynamic MR imaging with pathologic findings.

The purpose of this study is to clarify the changes of peripheral normal liver parenchyma before and after ethanol injection, with respect to MR appearances and pathologic findings and, in so doing, to clinically evaluate the therapeutic effectiveness of percutaneous ethanol injection (PEI) therapy. The normal liver in 12 rabbits was injected with ethanol. We performed conventional and dynamic MR imaging and prepared the histopathologic specimens 1 week (group 1), 2 weeks (group 2), and 1 month (group 3) after ethanol injection. On conventional MR images, coagulative necrosis in the normal liver was demonstrated as an area of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images in all groups. On dynamic MR images, contrast enhancement in the coagulative necrosis was not seen in groups 1 and 2; however, gradual and concentric enhancement was seen in the direction of the central necrotic portion from early-to-delayed phase image in group 3. Although signal intensity of the coagulative necrotic area in the normal liver after ethanol injection may mimic that of untreated or viable hepatocellular carcinoma (HCC) when clinically encountered on conventional MR images, coagulative necrosis of the normal liver parenchyma will be discriminated from viable HCC by using dynamic MR imaging.

Animals↗

Radial magnetic resonance imaging and pathological findings of acetabular labrum in dysplastic hips.

Radial MRI findings and pathological changes were comparatively examined in the acetabular labrum of 11 hips of 11 patients, who underwent total hip arthroplasty for osteoarthritis due to acetabular dysplasia. Diffuse high signal pattern on the radial MR images corresponded to histological degeneration of the labrum. High signal pattern which was equivalent to the synovial fluid, showed an intralabral tear. In the obscure areas of MR images, severe impairment of the labrum such as rupture, detachment, and displacement were found.

Journal Article↗