Regional migratory osteoporosis (RMO) is an uncommon self-limiting disease characterized by migrating bone marrow edema and osteoporosis. RMO of the knee with intra-articular migration is very rare. In such cases, different parts of the femur are usually involved. We report a case of intra-articular RMO of the knee migrating from the femur to the tibia—a pattern of migration that has not been previously described in the literature.
DOI : 10.1016/j.clinimag.2006.05.032 Anahtar Kelimeler :
Regional migratory osteoporosis, RMO, Bone marrow edema, Magnetic resonance imaging
ISSN: 0899-7071 Sayı: 6 Cilt: 30 Sayfa: 428-430
Objective: The purpose of the study was to determine the correlation between bony anatomic variations of the ostiomeatal unit (OMU) and chronic maxillary sinusitis. The study was based on the hypothesis that the mucosal contact caused by the variations represents the critical factor in increasing the risk of maxillary sinusitis. Materials and methods: Thin section high resolution computerised tomography (CT) examinations of the paranasal sinuses in 73 consecutive patients with 113 anatomic variations of the OMU were retrospectively reviewed. The following CT features were assessed: (1) Type of anatomic variations, (2) presence of a mucosal contact in the OMU and (3) presence of maxillary disease. Statistical evaluation was carried out using z2-test. Results: The following bony anatomic variations were found: Concha bullosa (67 cases), abnormalities of the uncinate process (18 cases), Haller's cells (24 cases) and large ethmoidal bulla (four cases). Only 52 of the 113 anatomic variations were associated with ipsilateral maxillary disease (mucosal thickening, mucous retention cysts, polyps, retained secretions). Of 113 variations, 44 caused a mucosal contact, 35 of these were associated with maxillary abnormalities, while in nine cases there were no pathologic changes. Of 69 variations, 17 did not cause mucosal contact (P < 0.05). Conclusion: Our data shows that, in the presence of anatomic bony variations, a contact between the mucosal surface of the OMU is valuable in predicting the likelihood of a maxillary inflammatory disease.
Ureteral myxedema is exceptionally rare. We describe computed tomography and magnetic resonance imaging findings in a case of ureteral myxedema. The demonstration of water-like hyperintensity around the ureteral lumen on heavily T2-weighted sequences should be considered a strongly suggestive sign for ureteral myxedema.
DOI : 10.1016/j.clinimag.2015.02.012 Anahtar Kelimeler :
Gravesu2019 disease, Ureteral myxedema, Magnetic resonance imaging, Magnetic resonance hydrography
ISSN: 0899-7071 Sayı: 4 Cilt: 39 Sayfa: 711-713
We report a case of transient bone marrow edema syndrome migrating within two different compartments of the same knee. This unusual pattern of migration of the marrow edema, which has been previously described only in three cases of transient osteoporosis, may raise the suspicion of an aggressive disease. Radiologists should be aware of this phenomenon in order to avoid an aggressive management of this self-limiting disease.
DOI : 10.1007/s00330-002-1584-y Anahtar Kelimeler :
Transient bone marrow edema syndrome Magnetic resonance Knee Bone marrow
ISSN: 0938-7994 1432-1084 Sayı: S3 Cilt: 12 Sayfa: S40-S42
Torsion of ovarian tumors is often difficult to diagnose, because of non-specific clinical, laboratory, and imaging findings. We report a case of twisted ovarian fibroma whose main characteristic was the presence of large areas of high signal intensity on both T1- and T2-weighted MR images due to the passive congestion of the mass. This previously unreported finding should be considered a sign of ovarian torsion and may facilitate prompt surgical intervention.
Abstract: Trichorhinophalangeal type I (TRPS I) is a rare autosomal dominant disorder characterized by variable clinical expression of sparse and slow‐growing hair, pear‐shaped nose, elongated philtrum, and bone deformities, including cone‐shaped epiphyses of the phalanges and short stature. We describe three members of a family who consulted us because of slow‐growing scalp hair with craniofacial and radiological features typical of TRPS I.
Renal cell carcinoma can recur at any time after nephrectomy, and it is not unusual to detect late metastases even decades after surgical excision of the primary tumor. Despite being infrequently reported, head and neck metastases may be linked to renal cell carcinoma in up to 15% of cases. We present an unusual case of a single metachronous renal cell carcinoma metastasis in the infratemporal fossa, with a 13-year late onset from the primary.
We reported the results of post mortem computed tomography of the liver in 27 subjects dead simultaneously during a flood. The aim of our work was to identify the different patterns of post mortem intrahepatic gas distribution and the timing of its appearance. Although post mortem CT is the method of choice for the evaluation of gas distribution, controversies exist about the first site of appearance of intrahepatic gas (portal veins versus hepatic veins) as well as the timing and steps of intrahepatic gas spreading. In each subject we performed thin slice CT scanner (Somatom Definition, Siemens) and post processing of native CT images with Minimum Intensity Projection technique. Our results show that the first site of appearance of intrahepatic gas is portal veins. Gas in hepatic veins was never seen without the presence of the gas in portal vein. Gaseous cysts in hepatic parenchyma represent a further and usually more tardive pattern of intrahepatic gas distribution. In addition, we demonstrated that differences in timing of gas spreading was statistically significative for exclusive presence of portal veins gas before 48 h as well as for complete substitution of hepatic parenchyma by cysts 64 h after death. In conclusion, our work shows that the CT study of postmortem intrahepatic gas distribution could be a useful complementary tool both in demonstrating the mechanism of intrahepatic gas spreading and in estimating post mortem interval.
DOI : 10.1016/j.legalmed.2017.09.002 Anahtar Kelimeler :
Post mortem CT, Liver, Putrefaction, Intrahepatic gas, Post mortem interval
ISSN: 1344-6223 Cilt: 29 Sayfa: 18-21
Objective To evaluate the role of MRI water-sensitive sequences in the differential diagnosis between pneumonia-like mucinous adenocarcinoma and infectious pneumonia. Subjects and methods Twenty-three patients with pneumonia-like mucinous adenocarcinoma and 30 patients with infectious pneumonia underwent computed tomography (CT) and MRI. Two blinded and independent readers evaluated CT and MR images using a 3-level confidence scale in two separate sessions. Results were tested for statistical significance using the Fisher's exact test and the Cohen's k test. Results On CT, the two readers respectively made correct diagnoses of mucinous adenocarcinoma in 17 out of 23 cases (73.9%), and in 15 out of 23 cases (65.2%). A correct diagnosis of infectious pneumonia was made in 22 out of 30 cases (73.3%), and in 24 out of 30 cases (80.0%). On MRI, both readers made correct diagnoses of mucinous adenocarcinoma in 23 out of 23 (100%) cases, and of infectious pneumonia in 30 out of 30 (100%) cases. Fisher's exact test showed a significant difference in the diagnosis of mucinous adenocarcinoma between MRI and CT for both readers, P = 0.01 for reader 1 and P = 0.002 for reader 2, respectively. A good agreement (k = 0.73) was found between the two readers on CT evaluation, whereas an almost perfect agreement (k = 1.00) was found for MRI. Conclusions MRI with “water-sensitive” sequences should be added in the diagnostic protocol of every patient with pulmonary consolidation suspected to be mucinous adenocarcinoma.
The term "pseudotumor" is used to refer to several anatomic variants that can simulate a renal mass, the most frequent of which are hypertrophied column of Bertin, persistence of fetal lobation, and the dromedary or splenic hump. We describe the findings of power Doppler US after the ultrasound contrast agent (Levovist, Schering, Berlin, Germany) administration in 4 patients with a renal focal lesion in whom gray-scale and baseline power Doppler US was not able to certainly differentiate pseudotumor from neoplasm.
DOI : 10.1007/s003300100861 Anahtar Kelimeler :
Renal pseudotumors Contrast-enhanced power Doppler US Contrast media Kidney
ISSN: 0938-7994 1432-1084 Sayı: 12 Cilt: 11 Sayfa: 2496-2499
MRI findings of a patient with dropped-head syndrome due to focal myositis of the neck extensor muscles are presented. MRI showed oedematous changes and marked enhancement of the neck extensor muscles. After therapy MRI demonstrated disappearance of the abnormal findings.
To report our experience with the use of intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) and dynamic contrast-enhanced (DCE)-MRI in bone marrow before and after administration of granulocyte colony-stimulating factor (GCSF). Moreover, a small series of patients with bone metastases from breast cancer have been evaluated by IVIM DW-MRI and DCE-MRI before and after GCSF administration. We studied with IVIM-MRI and DCE-MRI 14 patients with rectal or uterine cervix cancer studied before and 4–18 days after administration of GCSF; the second MR examination was obtained after three chemotherapy courses. IVIM perfusion fraction (f), pseudo-diffusion coefficient (D*), true diffusion coefficient (D) and apparent diffusion coefficient (ADC) as well area under the curve at 60 s (AUC60) were calculated for bone marrow before and after GCSF administration. Moreover, two different IVIM parametric maps (i.e., ADC and ADClow) were generated by selecting two different intervals of b values (0–1000 and 0–80, respectively). Furthermore, four patients affected by pelvic bone metastases from breast adenocarcinoma who received GCSF administration were also qualitatively evaluated for evidence of lesions on ADC maps, ADClow maps and DCE-MRI. ADC, D, D*, f and AUC60 values were significantly higher in hyperplastic bone marrow than in untreated bone marrow (p values < 0.0001, < 0.0001, < 0.001, < 0.001, < 0.0001, respectively). All bone metastases were clearly differentiable from hyperplastic bone marrow on ADClow maps, but not on ADC maps and DCE-MRI. MR functional imaging techniques, such as DW-, IVIM DW- and DCE-MRI are effective tools in assessing the response of bone marrow to the administration of growth factors. Although an overlap between signal of hyperplastic bone marrow and lytic bone metastases can occur on ADC maps and DCE-MRI, evaluation of ADClow maps by IVIM DW-MRI could permit to differentiate hyperplastic bone marrow from lytic bone metastases. Further studies are needed to confirm our data.
In the last decades, a number of Diffusion Weighted Imaging (DWI) based techniques have been developed to study non-invasively human brain tissues, especially white matter (WM). In this context, Constrained Spherical Deconvolution (CSD) is recognized as being able to accurately characterize water molecules displacement, as they emerge from the observation of MR diffusion weighted (MR-DW) images. CSD is suggested to be applied on MR-DW datasets consisting of b-values around 3,000 s/mm2 and at least 45 unique diffusion weighting directions. Below such technical requirements, Diffusion Tensor Imaging (DT) remains the most widely accepted model. Unlike CSD, DTI is unable to resolve complex fiber geometries within the brain, thus affecting related tissues quantification. In addition, thanks to CSD, an index called Apparent Fiber Density (AFD) can be measured to estimate intra-axonal volume fraction within WM. In standard clinical settings, diffusion based acquisitions are well below such technical requirements. Therefore, in this study we wanted to extensively compare CSD and DTI model outcomes on really low demanding MR-DW datasets, i.e., consisting of a single shell (b-value = 1,000 s/mm2) and only 30 unique diffusion encoding directions. To this end, we performed deterministic and probabilistic tractographic reconstruction of two major WM pathways, namely the Corticospinal Tract and the Arcuate Fasciculus. We estimated and analyzed tensor based features as well as, for the first time, AFD interpretability in our data. By performing multivariate statistics and tract-based ROI analysis, we demonstrate that WM quantification is affected by both the diffusion model and threshold applied to noisy tractographic maps. Consistently with existing literature, we showed that CSD outperforms DTI even in our scenario. Most importantly, for the first time we address the problem of accuracy and interpretation of AFD in a low-demanding DW setup, and show that it is still a biological meaningful measure for the analysis of intra-axonal volume even in clinical settings.
DOI : 10.3389/fneur.2018.00716 Anahtar Kelimeler :
AFD, CSD, DTI, arcuate fasciculus, corticospinal tract, diffusion MRI, tractography, white matter quantification
Bone stress injuries, whose incidence is increasing among competitive and recreational athletes, represent a pathophysiological continuum along which a bone responds to a changing mechanical environment. Frank stress fracture is the endpoint of this process, resulting from the accumulation of microinjuries due to repeated abnormal stresses. The legs are largely the most frequently affected bone district. The aim of this paper is to review the imaging findings of the whole spectrum of stress-induced bone lesions of the leg in athletes. We emphasise the role of computed tomography and magnetic resonance imaging, which allow recognition of early alterations.
Ossifying lipomas independent of bone tissue are very rare. A literature review revealed that only few cases of ossifying lipoma independent of bone tissue have been reported. None of the cases have been reported in the international radiology literature. In addition, there are no reports concerning the MRI features of this entity. We describe CT and MRI findings in a case of ossifying lipoma of the parapharyngeal space.
The authors report their own experience in obtaining pain relief in 13 recurrent or disseminated cancer patients affected by lumbosacral carcinomatous neuropathy (LCN). The site, where the disease involved the lumbosacral plexus or its branches, was palliatively irradiated with a few large fractions. The average duration of response was 196 days. Median survival (uncensored) was 185 days (range 47–636 days).
Osteoid osteoma (OO) is a benign bone tumor whose main radiological finding is nidus. OO of the proximal femur can also result in non-specific findings such as hip joint effusion, perinidal bone marrow edema and soft tissue mass. Since the nidus may be difficult to identify with MR, these non-specific findings can lead to erroneous diagnosis. Therefore, MR imaging technique should be optimized in order to identify nidus. Since MR imaging has assumed increasing importance in the evaluation of disorders of the hip, radiologists must be aware of the spectrum of findings of OO of the proximal femur. The aim of this pictorial review is to show the MR imaging findings of intra-articular and extra-articular OO of the proximal femur.
DOI : 10.1007/s00330-004-2293-5 Anahtar Kelimeler :
Femur, bone neoplasms, Femur, osteoid osteoma, Magnetic resonance imaging
ISSN: 0938-7994 1432-1084 Sayı: 9 Cilt: 14 Sayfa: 1582-1589
Giant cell tumor of the tendon sheath is a tumor, which affects mainly the hands of people aged 30 to 50 years with a female prevalence. Magnetic resonance imaging (MRI) is essential for diagnosis and treatment planning. The aim of this study is to evaluate the efficacy of multiecho gradient-echoes (MeGE) sequence in detecting hemosiderin which is the hallmark of this tumor. MRIs were performed in a sample of 11 patients with a mean age of 45. With the proposed protocol, all readers were able to detect the susceptibility artifacts due to the presence of hemosiderin. MeGE sequence allows to highlight the presence of hemosiderin, and the use of 3 echo times (ET) (8, 16, and 24 ms) is suggested.
DOI : https://doi.org/10.1155/2021/6689037
Cilt: 2021 ISSN: 2314-6133
Purpose Investigation of the feasibility of the R2⁎ mapping techniques by using latest theoretical models corrected for confounding factors and optimized for signal to noise ratio. Theory and methods The improvement of the performance of state of the art magnetic resonance imaging (MRI) relaxometry algorithms is challenging because of a non-negligible bias and still unresolved numerical instabilities. Here, R2⁎ mapping reconstructions, including complex fitting with multi-spectral fat-correction by using single-decay and double-decay formulation, are deeply studied in order to investigate and identify optimal configuration parameters and minimize the occurrence of numerical artifacts. The effects of echo number, echo spacing, and fat/water relaxation model type are evaluated through both simulated and in-vivo data. We also explore the stability and feasibility of the fat/water relaxation model by analyzing the impact of high percentage of fat infiltrations and local transverse relaxation differences among biological species. Results The main limits of the MRI relaxometry are the presence of bias and the occurrence of artifacts, which significantly affect its accuracy. Chemical-shift complex R2⁎-correct single-decay reconstructions exhibit a large bias in presence of a significant difference in the relaxation rates of fat and water and with fat concentration larger than 30%. We find that for fat-dominated tissues or in patients affected by extensive iron deposition, MRI reconstructions accounting for multi-exponential relaxation time provide accurate R2⁎ measurements and are less prone to numerical artifacts. Conclusions Complex fitting and fat-correction with multi-exponential decay formulation outperforms the conventional single-decay approximation in various diagnostic scenarios. Although it still lacks of numerical stability, which requires model enhancement and support from spectroscopy, it offers promising perspectives for the development of relaxometry as a reliable tool to improve tissue characterization and monitoring of neuromuscular disorders.
DOI : 10.1016/j.mri.2016.08.006 Anahtar Kelimeler :
Fat-water, Chemical shift, Multi Echo, R2u204E relaxometry, TRID, Neuromuscular disease
ISSN: 0730-725X Cilt: 35 Sayfa: 4-14
Aim To compare pancreatic virtual unenhanced (VUE) and true unenhanced (TUE) images and to calculate the potential dose reduction by omitting the conventional unenhanced scan. Materials and methods Fifty-one patients with known or suspected pancreatic masses underwent contrast-enhanced computed-tomography (CT) during unenhanced and portal venous phases acquired in single-energy (SE) mode, and pancreatic parenchymal phase acquired in dual-energy (DE) mode. The image quality (IQ) and image noise (IN) of TUE and VUE images were evaluated. The effective dose of a combined DE/SE dual-phase protocol was compared with that of a theoretical standard SE triple-phase protocol. The results were tested for statistical significance using the Cohen’s k, the Wilcoxon’s signed rank test, and the paired t-test; p-values of less than 0.05 were considered significant. Results Mean TUE and VUE IQ were 1.5 ± 0.6 and 1.6 ± 0.6 (k = 0.891), with no significant difference (p > 0.05). Mean TUE and VUE IN were 12.3 ± 1.6 and 10.3 ± 1.5 HU, and resulted significantly different (p < 0.001). Mean effective doses for a combined DE/SE dual-phase protocol and SE triple-phase protocol were 8.9 ± 2.4 mSv (range 4.8–16.2 mSv) and 12.1 ± 3.1 mSv (range 6.4–21.1 mSv). The calculated mean dose reduction achievable by omitting the unenhanced scan was 26.7 ± 9.7% (range 10–46.1; p < 0.001). Conclusion VUE images are feasible for pancreatic abdominal CT. A combined DE/SE dual-phase protocol permits a significant reduction in dose exposure to patients.
We present here the case of a 30-year-old man with a long term history of nephrotic syndrome (NS) who developed an episode of acute left main pulmonary artery thrombosis complicated by a lung abscess. During the hospital admission was also identified a concomitant hyperhomocysteinemia. After an atypical resection of the left upper pulmonary lobe and the starting of long term anticoagulation the patient was discharged but did not attend the planned follow up visits until one year later when he was seen again for severe dyspnea and exercise intolerance. At this time chronic thromboembolic pulmonary hypertension (CTEPH) was diagnosed by lung perfusion scintigraphy and right heart catheterization. He initially refused the surgical treatment but, after six months, for the presence of worsening dyspnea was referred for bilateral pulmonary endarterectomy followed by a cardio-thoracic rehabilitation program. After a follow-up of seven years the patient is alive and in stable conditions. NS and hyperhomocysteinemia are both known risk factors for pulmonary embolism (PE), but their association with CTEPH is extremely rare. We discuss here the possible mechanisms linking these conditions. CTEPH must be suspected in any patient with NS, with or without hyperhomocysteinemia, and unexplained dyspnea.
The postmortem interval is probably the most important puzzle piece in clarifying the circumstances in case of death occurred in unknown conditions. Over the years, radio-imaging modalities have proved their worth in forensic field, providing additional and significant improvements and findings. CT-scan is characterized by wide availability, fast scan times and sustainable healthcare costs. Detection of gas, hemorrhage and bone fractures are points of strength of CT-scan. A reliable evaluation of the post-mortem interval is interesting in the victims of a mass disaster, also following a natural disaster, for the individuation of responsibility in the efficiency of the help and assistance. This work is based on the postmortem CT-scan evaluation of 26 people sadly died during a tragic flood occurred in 2009 in Giampilieri (Italy). In particular, the gas distribution within the skeletal bones was evaluated, with recognition of specific patterns that were then related to the time of death. The identification of intraosseous gas could represent a helpful tool in the estimation of postmortem interval.
DOI : 10.1016/j.fri.2020.200414 Anahtar Kelimeler :
Postmortem interval, CT-scan, Intraosseous gas distribution
ISSN: 2666-2256 Sayfa: 200414
The authors describe magnetic resonance (MR) findings in eight patients with histologically confirmed focal myositis. In each patient, axial TSE T1-weighted and fast short-tau inversion recovery (STIR) images were obtained using a 1.5-T MR scanner. Three patients also underwent dynamic contrast-enhanced MR examination using a GE T1-weighted sequence. The following features were evaluated: anatomical distribution, extent of the involvement, signal intensity characteristics, dynamic enhancement pattern and outcome at follow-up examinations. Seven of eight lesions were located in the lower extremities, one of eight in the arm; four of eight involved part of a muscle, two of eight diffusely involved a muscle and two of eight showed multifocal involvement of two or more muscles. All lesions were hyperintense on fast-STIR images: the hyperintensity was homogeneous in six of eight and inhomogeneous in two of eight. On T1-weighted unenhanced images, all lesions but two appeared isointense or slightly hypointense in comparison to normal muscles; two lesions showed a slight hyperintensity. Dynamic enhancement pattern corresponded to the type usually seen in benign soft tissue lesions. All lesions disappeared. Focal myositis is an uncommon pseudotumour which should be considered in the differential diagnosis of muscular masses and myopathies.
Chanarin–Dorfman disease (CDD) is a rare genetic disorder characterized by ichthyosis, myopathy, central nervous system disturbances, and intracellular lipid storage in muscle fibers, hepatocytes, and granulocytes. We describe skeletal muscle magnetic resonance imaging findings in a case of CDD, outlining the potential role of GE T1-weighted opposed-phase sequence (chemical shift imaging) in the evaluation of lipid storage myopathies.
Rational and To investigate whether a nonlinear-blending algorithm improves tumor conspicuity and image quality in the evaluation of renal masses at dual-energy computed tomography (DECT) during nephrographic phase of enhancement. Materials and Methods The Institutional Review Board approved this retrospective study from archival material from patients consenting to the use of medical records for research purposes. A retrospective review of contrast-enhanced abdominal DECT scans in 45 patients (mean age, 59.5 years; range, 24–84 years) was performed. DECT data were reconstructed using nonlinear and linear blending. A region of interest was located within tumors and adjacent normal parenchyma; attenuation differences and contrast-to-noise ratios (CNRs) were calculated for renal masses on nonlinear- and linear-blended images. The two datasets were subjectively compared in terms of tumor detection and image quality. An exact Wilcoxon's matched pairs signed rank and marginal homogeneity tests were used to test whether differences in attenuation, CNR, and subjective assessment were greater using nonlinear blending. Results The mean difference in attenuation for renal masses and adjacent portion of renal parenchyma was 138.4 Hounsfield units ± 28.9 SD using nonlinear blending, and 121.6 HU ± 18.0 SD using linear blending (P < .001). Mean CNR was 12.6 ± 2.5 SD using nonlinear blending, and 9.6 ± 2.2 SD using 0.3 linear-blended (P < .001). No significant difference in tumor detection was observed between the two algorithms. Image quality was significantly better (P < .001) using nonlinear blending. Conclusion Compared with standard linear blending, nonlinear-blending algorithm improves tumor conspicuity and image quality in renal masses at DECT evaluation during nephrographic phase of enhancement.
Bronchial mucus has tomodensitometric features and MR signal intensity similar to that of water. However, chronic entrapped mucus collections, due to water reabsorption and higher protein content, can have CT attenuation values higher than 20 and reaching even 130 HU. Higher protein concentration also causes a sensible reduction in T1 relaxation time. The demonstration of mucus within a mediastinal, bronchial or pulmonary lesion is an important diagnostic clue permitting remarkable shortening of the list of differential diagnoses. This article illustrates the CT and MR findings allowing correct characterization of the mucus-containing lesions of mediastinum, bronchi, and lung.