scholarly journals Impact of magnetic resonance imaging on the diagnosis of abdominal complications of paroxysmal nocturnal hemoglobinuria

Blood ◽  
1995 ◽  
Vol 85 (11) ◽  
pp. 3283-3288 ◽  
Author(s):  
D Mathieu ◽  
A Rahmouni ◽  
P Villeneuve ◽  
MC Anglade ◽  
H Rochant ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Mr Imaging ◽  
Iron Overload ◽  
Signal Intensity ◽  
Paroxysmal Nocturnal Hemoglobinuria ◽  
Renal Cortex ◽  
Iron Storage ◽  
Abdominal Complications ◽  
Vein Thrombosis ◽  
Hepatic Vein Obstruction

Magnetic resonance (MR) imaging is a method of choice for assessing vascular patency and parenchymal iron overload. During the course of paroxysmal nocturnal hemoglobinuria (PNH), it is clinically relevant to differentiate abdominal vein thrombosis from hemolytic attacks. Furthermore, the study of the parenchymal MR signal intensity adds informations about the iron storage in kidneys, liver, and spleen. Twelve PNH patients had 14 MR examinations of the abdomen with spin-echo T1- and T2-weighted images and flow-sensitive gradient echo images. Vessels patency and parenchymal signal abnormalities--either focal or diffuse--were assessed. MR imaging showed acute complications including hepatic vein obstruction in five patients, portal vein thrombosis in two patients, splenic infarct in one patient. In one patient treated with androgens, hepatocellular adenomas were shown. Parenchymal iron overload was present in the renal cortex of eleven patients with previous hemolytic attacks. On the first MR study of the remaining patient with an acute abdominal pain showing PNH, no iron overload was present in the renal cortex. Follow-up MR imaging showed the onset of renal cortex iron overload related to multiple hemolytic attacks. Despite the fact that all our patients were transfused, normal signal intensity of both liver and spleen was observed in three of them. MR imaging is particularly helpful for the diagnosis of abdominal complications of PNH.

Value Of Magnetic Resonance Imaging In The Study and Follow-Up Of Paroxysmal Nocturnal Hemoglobinuria

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4872-4872
Author(s):  
Ana Villegas ◽  
Ataulfo Gonzalez ◽  
Fatima Matute ◽  
Jorge Martinez Nieto ◽  
Felix de la Fuente
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Paroxysmal Nocturnal Hemoglobinuria ◽  
Renal Cortex ◽  
Conflicts Of Interest ◽  
Iron Accumulation ◽  
Renal Tubules ◽  
Myocardial Iron ◽  
Signal Loss ◽  
Resonance Imaging

Abstract Introduction Renal damage is relatively frequent in Paroxysmal Nocturnal Hemoglobinuria (PNH). Iron accumulation from hemolysis in the renal tubules has been found to be one of the triggering factors. Hemosiderin accumulates in the epithelial cells of the proximal renal tubules localized in the renal cortex, and they can be measured (and monitoring) using magnetic resonance imaging (MRI). Methods We studied 7 PNH patients with MR using T2-weighted gradient echo and multiecho sequences. We quantified renal, hepatic and myocardial iron with T2* relaxometry model. Four of these patients were studied at diagnosis and after 1 year of treatment with eculizumab. In 2 of them the MRI was done after 2 and 3 years respectively of treatment with eculizumab. One patient was studied after 8 months on eculizumab, and MRI was repeated at 12 and 24 months. Liver and myocardial iron deposition was quantified in all cases. Results At diagnosis the median hemoglobin of the 7 patients was 8.9 g/dl (8.2-12-4), the PNH median PNH clone size was 77% (60-90) and the median LDH level was 2340 U/L (1100-3600). Three patients presented an important accumulation of iron in the renal cortex, with much lower signal intensity than the medulla in the T2-weighted MR images. One patient with mild hemolysis (Hb 12.4 g/dl, 20% reticulocytes and 1,100 LDH) did not present iron accumulation in the renal cortex, and neither did the 2 patients studied after 2 a 3 years of eculizumab treatment. All the patients improved, presenting median of Hb of 11,2 g/dl ( 9,5-12,9) and of LDH of 520 U/L ( 430- 721). The patient studied after 8 months showed an increase of iron in the renal cortex that persisted, despite the improvement with the treatment with eculizumab, with increase of the Hb and decrease of the LDH levels; this patients had a C hepatitis and positivity on the hemochromatosis genes C282Y/H63D, with important iron hepatic overload (11-17 mgFe/g). In the rest of the patients the hepatic iron was normal, with values from 0.5 to 2 mgFe/g, except in one case where the levels were higher (10 mgFe/g) due to previous transfusions used to treat an aplastic anemia pre-PNH. Myocardial iron was normal in the 7 patients, with values ranging from 33 to 60 ms in T2. Only one of the patients presented several episodes of acute renal insufficiency, related with hemolytic crisis, with residual proteinuria, that disappeared when treated with eculizumab. Conclusions A diffuse signal loss in the renal cortex without liver and spleen alteration is indicative of intravascular hemolysis, suggesting PNH. Serial MRI studies of iron overload in the renal cortex can be used for the diagnosis, and for monitoring the effects of treatment. Disclosures: No relevant conflicts of interest to declare.

Paroxysmal Nocturnal Hemoglobinuria and Magnetic Resonance Imaging

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 4873-4873 ◽  
Author(s):  
Miguel Pastrana ◽  
Cristina Muñoz-Linares ◽  
Emilio Ojeda ◽  
Rafael Fores ◽  
Beatriz Brea ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Bone Marrow ◽  
Magnetic Resonance ◽  
Iron Overload ◽  
Paroxysmal Nocturnal Hemoglobinuria ◽  
Imaging Technique ◽  
Resonance Imaging ◽  
Abdominal Mri ◽  
Thoracic And Abdominal ◽  
Pnh Clone

Abstract Paroxysmal Nocturnal Hemoglobinuria (PNH) is a rare and complex disease characterized by a severe prothrombotic state caused by a complement system mediated hemolysis. The introduction of the anti-C5 antibody, Eculizumab, has been conducted in many Hematology units worldwide to adopt new diagnostic tools to evaluate new and old PNH patients in order to consider the adequacy of the adoption of this new drug in each case. Magnetic Resonance Imaging (MRI) allows a more adequate and profitable approach in PNH that other radiology techniques used for this purpose. In the last four years Hematology and Radiology units in our Hospital have collaborate in the clinical evaluation of PNH patients performing MRI (cranioencephalic, thoracic and/or abdominal) in acute complications of PNH patients (9 patients) or as a programmed protocoled evaluation previous to consider Eculizumab treatment (14 patients). The protocoled evaluation consists in thoracic and abdominal MRI evaluations in all cases, and cranioencephalic MRI (with independence of the presence of neurological symptoms) in 9 cases. The PNH patients were examined with 1.5 Teslas magnet for cranioencephalic,thoracic and abdominal MRI and with 3.0 Teslas magnet for some cranioencephalic MRI (Achieva Magnets; Philips Healthcare, Best, The Netherlands). Different protocols designed for the study of this pathology, using morphological sequences with different empowerment, functional sequences and angiographic studies after administration of intravenous contrast (gadobutrol) have been used. In the abdominal explorations had been performed calculations of T2 * for the quantification of deposit of iron in liver and kidney. The first group of patients (incidental studies in acute/chronic situations) included Classical and with other bone marrow failure syndrome (BMFS) Parker’s types. The second group (protocoled studies previous consideration of Eculizumab therapy) consisted on 11 Classical Parker’s type patients with active hemolysis (LDH increased 3-13 times over normal levels) and elevated PNH clone (73-99% negative GPI granulocytes by FLAER cytometry); and 3 with BMFS Parker’s type patients (LDH increased 2-6 times over normal levels) with lower PNH clone (43-50% negative GPI granulocytes by FLAER cytometry). Thrombosis was found in four cases, one in the inferior cava and and three arterial (two cerebral and one in descendent aorta). In three patients this finding implied to initiate Eculizumab therapy. Minor ischemic brain changes were displayed by three patients. None of the eighteen patients explored with thoracic MRI, displayed pulmonary hypertension signs despite the elevation of pro-BNP in eight of them. Iron overload in the liver and/or kidneys were very frequent. The finding of a reversal of the normal cortical and medullary intensities on T1 and T2 weighted images of both kidneys was evident in the majority of patients with severe PNH types. Interestingly, one patient with a chronic PNH severe form displayed no renal iron cortical after two years on Eculizumab therapy. This finding was also evident in patients with active hemolysis in the past but with very low PNH clones and clinical remission of the disease. Many other incidental discoveries includes cholelithiasis, splenomegaly, kidney arterial vessel constriction, vascular anomalies, kidney and vesical stones, adrenal adenoma, atheromatosis at different levels, Tornwaldt cyst, hamartoma, hemangiomas and abnormal bone marrow signal. MRI is the best imaging technique to diagnose thrombosis in PNH patients and to control evolution. Moreover, in the cerebrovascular setting allows a more fine and precise diagnosis of the minor pathologic thrombotic changes. MRI is the only imaging technique that permits to evaluate the iron overload that in some PNH cases could be underestimated and needs quelation therapy. In our opinion all new patients with classical severe hemolytic PNH must be evaluated prospectively with MRI. The collaboration of the Radiology team with the Hematologist is fundamental to acquire expertise in this rare disease. Disclosures: Pastrana: Alexion Pharmaceuticals: Speakers Bureau. Ojeda:Alexion Pharmaceuticals: Consultancy, Speakers Bureau.

Mr Imaging of Acute Renal Cortical Necrosis

1992 ◽  
Vol 33 (5) ◽  
pp. 431-433 ◽  
Author(s):  
S. H. Kim ◽  
M. C. Han ◽  
S. Kim ◽  
J. S. Lee
Keyword(s):  
Mr Imaging ◽  
Signal Intensity ◽  
Renal Cortex ◽  
Pulse Sequences ◽  
Conventional Radiography ◽  
Massive Bleeding ◽  
High Signal ◽  
Cortical Necrosis ◽  
Renal Cortical Necrosis

MR imaging of a patient with acute renal cortical necrosis secondary to massive bleeding following an abortion is presented. The kidneys were enlarged with a high signal intensity observed in the renal cortex on both T1- and T2-weighted images. Follow-up MR imaging showed thinned renal cortex of low signal intensity on both pulse sequences representing renal cortical calcification which was confirmed on conventional radiography and CT.

Prognostic relevance of the postoperative evolution of intramedullary spinal cord changes in signal intensity on magnetic resonance imaging after anterior decompression for cervical spondylotic myelopathy

2007 ◽  
Vol 7 (6) ◽  
pp. 615-622 ◽  
Author(s):  
Luciano Mastronardi ◽  
Ahmed Elsawaf ◽  
Raffaelino Roperto ◽  
Alessandro Bozzao ◽  
Manuela Caroli ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Signal Intensity ◽  
Cervical Spondylotic Myelopathy ◽  
Mr Images ◽  
Intramedullary Spinal Cord ◽  
Signal Changes ◽  
T1 And T2 ◽  
T2 Weighted Images

Object Areas of intramedullary signal intensity changes (hypointensity on T1-weighted magnetic resonance [MR] images and hyperintensity on T2-weighted MR images) in patients with cervical spondylotic myelopathy (CSM) have been described by several investigators. The role of postoperative evolution of these alterations is still not well known. Methods A total of 47 patients underwent MR imaging before and at the end of the surgical procedure (intraoperative MR imaging [iMRI]) for cervical spine decompression and fusion using an anterior approach. Imaging was performed with a 1.5-tesla scanner integrated with the operative room (BrainSuite). Patients were followed clinically and evaluated using the Japanese Orthopaedic Association (JOA) and Nurick scales and also underwent MR imaging 3 and 6 months after surgery. Results Preoperative MR imaging showed an alteration (from the normal) of the intramedullary signal in 37 (78.7%) of 47 cases. In 23 cases, signal changes were altered on both T1- and T2-weighted images, and in 14 cases only on T2-weighted images. In 12 (52.2%) of the 23 cases, regression of hyperintensity on T2-weighted imaging was observed postoperatively. In 4 (17.4%) of these 23 cases, regression of hyperintensity was observed during the iMRI at the end of surgery. Residual compression on postoperative iMRI was not detected in any patients. A nonsignificant correlation was observed between postoperative expansion of the transverse diameter of the spinal cord at the level of maximal compression and the postoperative JOA score and Nurick grade. A statistically significant correlation was observed between the surgical result and the length of a patient's clinical history. A significant correlation was also observed according to the preoperative presence of intramedullary signal alteration. The best results were found in patients without spinal cord changes of signal, acceptable results were observed in the presence of changes on T2-weighted imaging only, and the worst results were observed in patients with spinal cord signal changes on both T1- and T2-weighted imaging. Finally, a statistically significant correlation was observed between patients with postoperative spinal cord signal change regression and better outcomes. Conclusions Intramedullary spinal cord changes in signal intensity in patients with CSM can be reversible (hyperintensity on T2-weighted imaging) or nonreversible (hypointensity on T1-weighted imaging). The regression of areas of hyperintensity on T2-weighted imaging is associated with a better prognosis, whereas the T1-weighted hypointensity is an expression of irreversible damage and, therefore, the worst prognosis. The preliminary experience with this patient series appears to exclude a relationship between the time of signal intensity recovery and outcome of CSM.

scholarly journals T2∗ Relaxation Time Obtained from Magnetic Resonance Imaging of the Liver Is a Useful Parameter for Use in the Construction of a Murine Model of Iron Overload

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Yukari Matsuo-Tezuka ◽  
Yusuke Sasaki ◽  
Toshiki Iwai ◽  
Mitsue Kurasawa ◽  
Keigo Yorozu ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Iron Overload ◽  
Serum Ferritin ◽  
Murine Model ◽  
Resonance Imaging ◽  
Iron Storage ◽  
Body Iron ◽  
Inflammatory Status

Aim. Iron overload is a life-threatening disorder that can increase the risks of cancer, cardiovascular disease, and liver cirrhosis. There is also a risk of iron overload in patients with chronic kidney disease. In patients with renal failure, iron storage is increased due to inadequate iron utilization associated with decreased erythropoiesis and also to the inflammatory status. To evade the risk of iron overload, an accurate and versatile indicator of body iron storage in patients with iron overload is needed. In this study, we aimed to find useful iron-related parameters that could accurately reflect body iron storage in mice in order to construct a murine model of iron overload. Methods. To select an appropriate indicator of body iron status, a variety of parameters involved in iron metabolism were evaluated. Noninvasively measured parameters were R1, R2, and R2∗ derived from magnetic resonance imaging (MRI). Invasively measured parameters included serum hepcidin levels, serum ferritin levels, and liver iron contents. Histopathological analysis was also conducted. Results/Conclusion. Among the several parameters evaluated, the MRI T2∗ relaxation time was able to detect iron storage in the liver as sensitively as serum ferritin levels. Moreover, it is expected that using an MRI parameter will allow accurate evaluation of body iron storage in mice over time.

The detection of bone marrow involvement by lymphoma using magnetic resonance imaging.

1987 ◽  
Vol 5 (2) ◽  
pp. 225-230 ◽  
Author(s):  
A F Shields ◽  
B A Porter ◽  
S Churchley ◽  
D O Olson ◽  
F R Appelbaum ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Signal Intensity ◽  
Imaging System ◽  
Pulse Sequence ◽  
Spin Echo ◽  
Bone Marrow Involvement ◽  
Marrow Fat ◽  
Spin Echo Sequence

We used magnetic resonance (MR) to image the bone marrow of 31 patients with lymphoma. Images were obtained of the femoral, pelvic, and vertebral marrow with a 0.15 tesla imaging system using a T1-weighted spin echo sequence (TR600/TE 40). With this pulse sequence, normal marrow produces a high intensity signal that reflects the presence of marrow fat (short T1 relaxation time). We previously reported MR imaging of patients with leukemia in relapse and found a diffusely and symmetrically decreased marrow signal intensity due to the replacement of normal marrow fat by cellular material with a long T1. Unlike leukemia, patients with lymphomatous marrow involvement often had patchy, often discrete, areas of low signal intensity, representing focal marrow infiltration. Five of six patients in this study with lymphoma detected by histologic examination also had marrow lesions seen on MR. An additional four patients had marrow lesions detected by MR that were not detected on initial marrow biopsies; two of these had marrow involvement proven on subsequent biopsies, one had disease isolated to the vertebrae that was never pathologically documented, and one had progression of disease in the marrow documented by MR without biopsy confirmation. These results indicate that marrow involvement with lymphoma can be detected by MR imaging and that MR can complement bone marrow biopsy.

Assessment of Liver Iron Overload in Thalassemic Patients by Mr Imaging

1992 ◽  
Vol 33 (4) ◽  
pp. 347-350 ◽  
Author(s):  
N. Villari ◽  
D. Caramella ◽  
A. Lippi ◽  
C. Guazzelli
Keyword(s):  
Mr Imaging ◽  
Iron Overload ◽  
Signal Intensity ◽  
Liver Parenchyma ◽  
Hepatic Iron ◽  
Liver Iron ◽  
Hepatic Iron Overload ◽  
Liver Iron Overload

The use of MR imaging has been proposed for the assessment of the hepatic iron overload in transfusion-dependent thalassemic patients treated with desferrioxamine. The aim of the study was to correlate serum ferritine levels and MR signal intensity of the liver parenchyma. Results on 12 patients showed that the ratios between the signal intensity of liver parenchyma and muscle and fat are promising parameters for predicting iron overload.

scholarly journals Efficiency of Fat Suppression in T1-Weighted Inner Ear Magnetic Resonance Imaging: Multipoint Dixon Method Versus Hybrid Techniques

2021 ◽  
Vol 17 ◽  
Author(s):  
Pinar Cakmak ◽  
Duygu Herek ◽  
Ahmet Baki Yagci ◽  
Ergin Sagtas ◽  
Furkan UFUK ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Magnetic Resonance ◽  
Image Quality ◽  
Mr Imaging ◽  
Inner Ear ◽  
Signal Intensity ◽  
Signal To Noise Ratio ◽  
Fat Suppression ◽  
Signal To Noise ◽  
Hybrid Techniques

Background:: Temporal bone is a region where fat suppression is difficult due to the inhomogeneity of various structures with different molecular properties. Introduction: We aimed to determine the most effective fat suppression sequence in order to increase the visibility of the inner ear region. Methods: The hybrid techniques and T1-Weighted mDIXON images of 40 patients with Magnetic Resonance (MR) imaging of the inner ear were prospectively compared by two experienced radiologists in terms of fat suppression efficacy. In all fat-suppressed sequences, the signal to noise ratio (SNR), the spinal cord signal intensity / mean fat signal intensity ratio and spinal cord signal to noise ratio were calculated. Suppression efficacy of MR techniques for fat areas in the inner ear were visually graded. Results: Qualitative assessment of image quality due to fat suppression in the inner ear; the Dixon technique showed significantly better than SPAIR and SPIR techniques (p<0.0001). Mean signal intensity of the inner ear fat and SNR for Dixon technique were significantly lower than that for SPIR and SPAIR techniques (p<0.0001). Inter-observer agreement for the measurement of the inner ear fat mean signal intensity values and mean SNR values for fat suppression techniques were excellent. Conclusion: The Dixon technique has higher image quality and fat suppression efficiency than the hybrid techniques in MR imaging of the inner ear.

Magnetic Resonance Imaging of Deep Vein Thrombi Correlates with Response to Thrombolytic Therapy

1995 ◽  
Vol 73 (03) ◽  
pp. 386-391 ◽  
Author(s):  
Charles W Francis ◽  
Saara Totterman
Keyword(s):  
Magnetic Resonance ◽  
Mr Imaging ◽  
Thrombolytic Therapy ◽  
Signal Intensity ◽  
Bleeding Complications ◽  
Clot Lysis ◽  
Symptom Duration ◽  
Duration Of Symptoms ◽  
Partially Occluded ◽  
Deep Vein

SummaryFibrinolytic therapy can result in rapid lysis of deep vein thrombi (DVT), but its use is limited by the failure of many patients to respond and by the increased risk of bleeding complications in comparison with anticoagulant therapy alone. Treatment could be improved by the ability to select patients most likely to respond. Since magnetic resonance (MR) imaging may be sensitive to thrombus age and structure, properties related to thrombolytic sensitivity, we have evaluated the ability of MR imaging to predict the response of DVT to thrombolytic therapy. Nine patients with venographically documented proximal DVT were treated with streptokinase, and MR imaging using a gradient recall echo sequence was performed before and after therapy. The proximal leg veins were divided into nine segments in each patient, and thrombus was present in 55 segments. The MR appearance of the thrombus in each segment was evaluated prior to therapy, and the amount of clot lysis was determined by comparing pre- and post-treatment MR images. MR imaging accurately identified thrombus in all cases in comparison with venography and also identified proximal extension into pelvic veins that was not identified venographically. Prior to treatment, the thrombus in eight of nine patients varied in appearance in different vein segments consistent with a course of progressive extension over time. Thrombi with low MR signal occurred more often in patients with symptoms of four days or less, and were also more common in partially occluded segments (10/12, 83%) than with total occlusion (7/43, 16%) (p < .001). Clot lysis correlated with the appearance of the thrombi occurring in 9/17 (53%) segments with a uniform low signal intensity compared to 2/38 segments (5%) with areas of high or intermediate intensity (p < .001). Clot lysis was also correlated with partial vein occlusion and with symptom duration of 4 days or less. However, even among partially occluded segments and in patients with shorter duration of symptoms, clot lysis occurred significantly more often in segments with low MR signal intensity. The association of low MR signal intensity with both shorter symptom duration and incomplete vein obstruction suggests that this appearance identifies newly formed thrombi which may be responsive to thrombolytic therapy. We conclude that MR imaging may be useful in predicting response and selecting patients for thrombolytic therapy.

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