Thoracic calcifications on magnetic resonance imaging: correlations with computed tomography

ABSTRACT Objective: To identify the characteristics of thoracic calcifications on magnetic resonance (MR) imaging, as well as correlations between MR imaging and CT findings. Methods: This was a retrospective study including data on 62 patients undergoing CT scans and MR imaging of the chest at any of seven hospitals in the Brazilian states of Rio Grande do Sul, São Paulo, and Rio de Janeiro between March of 2014 and June of 2016 and presenting with calcifications on CT scans. T1- and T2-weighted MR images (T1- and T2-WIs) were semiquantitatively analyzed, and the lesion-to-muscle signal intensity ratio (LMSIR) was estimated. Differences between neoplastic and non-neoplastic lesions were analyzed. Results: Eighty-four calcified lesions were analyzed. Mean lesion density on CT was 367 ± 435 HU. Median LMSIRs on T1- and T2-WIs were 0.4 (interquartile range [IQR], 0.1-0.7) and 0.2 (IQR, 0.0-0.7), respectively. Most of the lesions were hypointense on T1- and T2-WIs (n = 52 [61.9%] and n = 39 [46.4%], respectively). In addition, 19 (22.6%) were undetectable on T1-WIs (LMSIR = 0) and 36 (42.9%) were undetectable on T2-WIs (LMSIR = 0). Finally, 15.5% were hyperintense on T1-WIs and 9.5% were hyperintense on T2-WIs. Median LMSIR was significantly higher for neoplastic lesions than for non-neoplastic lesions. There was a very weak and statistically insignificant negative correlation between lesion density on CT and the following variables: signal intensity on T1-WIs, LMSIR on T1-WIs, and signal intensity on T2-WIs (r = −0.13, p = 0.24; r = −0.18, p = 0.10; and r = −0.16, p = 0.16, respectively). Lesion density on CT was weakly but significantly correlated with LMSIR on T2-WIs (r = −0.29, p < 0.05). Conclusions: Thoracic calcifications have variable signal intensity on T1- and T2-weighted MR images, sometimes appearing hyperintense. Lesion density on CT appears to correlate negatively with lesion signal intensity on MR images.

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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

Journal of Neurosurgery Spine ◽

10.3171/spi-07/12/615 ◽

2007 ◽

Vol 7 (6) ◽

pp. 615-622 ◽

Cited By ~ 87

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.

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Magnetic Resonance Imaging with Maximum Contrast between Two Selected Tissues Composed of Recordings with Three Repetition Times

Acta Radiologica ◽

10.1177/028418518802900129 ◽

1988 ◽

Vol 29 (1) ◽

pp. 140-142

Author(s):

B. Jung ◽

A. Ericsson ◽

A. Hemmingsson ◽

G. O. Sperber ◽

K.-Å. Thuomas

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Mr Imaging ◽

Liver Metastases ◽

Normal Liver ◽

Liver Parenchyma ◽

Intensity Difference ◽

Resonance Imaging ◽

Mr Images ◽

Imaging Parameters

A method is presented which in a composed image maximizes the image intensity difference between two selected tissues. The composition is made from several magnetic resonance (MR) images from the same slice but with different MR imaging parameters. The method is illustrated with a patient with liver metastases for whom the technique was used to emphasize metastases above normal liver parenchyma.

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Syringomyelia-Chiari complex: magnetic resonance imaging and clinical evaluation of surgical treatment

Journal of Neurosurgery ◽

10.3171/jns.1990.73.1.0064 ◽

1990 ◽

Vol 73 (1) ◽

pp. 64-68 ◽

Cited By ~ 76

Author(s):

Jesús Vaquero ◽

Roberto Martínez ◽

Alicia Arias

Keyword(s):

Magnetic Resonance ◽

Mr Imaging ◽

Posterior Fossa ◽

Surgical Techniques ◽

Posterior Fossa Decompression ◽

Subjective Improvement ◽

Resonance Imaging ◽

Mr Images ◽

Content Type ◽

Spinal Cord Damage

✓ Thirty patients with syringomyelia-Chiari complex who underwent posterior fossa decompression or syringosubarachnoid shunting were studied clinically and by magnetic resonance (MR) imaging to assess the changes in the syrinx and in their clinical picture after surgery. When symptoms of posterior fossa compression were present, posterior fossa decompression was performed; however, when symptoms of posterior fossa compression were absent, the choice of posterior fossa decompression or syringosubarachnoid shunting depended, respectively, on whether the syrinx was narrow or wide on MR imaging. At least 1 year after surgery, subjective improvement or arrest of disease was recorded in 73% of the patients. The present study suggests that: 1) the symptoms attributed to spinal cord damage have no significant relationship to the size of the syrinx on MR images; 2) the surgical techniques employed in this series (posterior fossa decompression or syringosubarachnoid shunt) were equally useful in inducing syrinx collapse; and 3) when posterior fossa decompression is performed, plugging of the obex is not necessary for syrinx collapse.

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Magnetic Resonance Image Characterization of Knee Meniscus Signal Intensity using Crue’s Approach: Results from a Multi-centre Evidence

Advances in Bioscience and Clinical Medicine ◽

10.7575/aiac.abcmed.v.9n.3p.15 ◽

2021 ◽

Vol 9 (3) ◽

pp. 15

Author(s):

Akwa E. Erim ◽

Benjamin E. Udoh ◽

Pius Agweye ◽

Ofonime Ukweh ◽

Anthony C. Ugwu

Keyword(s):

Magnetic Resonance ◽

Signal Intensity ◽

Resonance Imaging ◽

Mr Images ◽

Meniscal Lesion ◽

Knee Meniscus ◽

Meniscal Lesions ◽

Grade 3 ◽

And Gender

This study aimed to characterize knee meniscus signal-intensity using magnetic resonance imaging. Our research included knee MR images of 138 subjects from multi-centres in Nigeria, between September 2016 and December 2017. Knee images were retrieved from patients' folder of MRI scanners and transfered to a DICOM workstation (Onis 2.6) for image analysis. Knee meniscus was characterized into 0, 1, 2 & 3 grades using Crue’s grading approach. Our research revealed 58% incidence of meniscal lesion. Study yielded a significant relationship between meniscal lesion and gender (p <.005) with a greater proportion of these lesions in women than in men. Meniscal lesions showed significant association with osteoarthritis (OA) (p < 0.05). Grade 3 lesions (actual tears) were largely of horizontal configuration.

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Magnetic resonance imaging: an accurate method to evaluate arteriovenous malformations after stereotactic radiosurgery

Journal of Neurosurgery ◽

10.3171/jns.1996.85.6.1044 ◽

1996 ◽

Vol 85 (6) ◽

pp. 1044-1049 ◽

Cited By ~ 127

Author(s):

Bruce E. Pollock ◽

Douglas Kondziolka ◽

John C. Flickinger ◽

Atul K. Patel ◽

David J. Bissonette ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Mr Imaging ◽

Cerebral Angiography ◽

False Negative ◽

Resonance Imaging ◽

Mr Images ◽

Content Type ◽

Fine Print

✓ To determine the accuracy of magnetic resonance (MR) imaging in comparison to cerebral angiography after radiosurgery for an arteriovenous malformation (AVM), the authors reviewed the records of patients who underwent radiosurgery at the University of Pittsburgh Medical Center before 1992. All patients in the analysis had AVMs in which the flow-void signal was visible on preradiosurgical MR imaging. One hundred sixty-four postradiosurgical angiograms were obtained in 140 patients at a median of 2 months after postradiosurgical MR imaging (median 24 months after radiosurgery). Magnetic resonance imaging correctly predicted patency in 64 of 80 patients in whom patent AVMs were seen on follow-up angiography (sensitivity 80%) and angiographic obliteration in 84 of 84 patients (specificity 100%). Overall, 84 of 100 AVMs in which evidence of obliteration was seen on MR images displayed angiographic obliteration (negative predictive value, 84%). Ten of the 16 patients with false-negative MR images underwent follow-up angiography: in seven the lesions progressed to complete angiographic obliteration without further treatment. Exclusion of these seven patients from the false-negative MR imaging group increases the predictive value of a negative postradiosurgical MR image from 84% to 91%. No AVM hemorrhage was observed in clinical follow up of 135 patients after evidence of obliteration on MR imaging (median follow-up interval 35 months; range 2–96 months; total follow up 382 patient-years). Magnetic resonance imaging proved to be an accurate, noninvasive method for evaluating the patency of AVMs that were identifiable on MR imaging after stereotactic radiosurgery. This imaging modality is less expensive, more acceptable to patients, and does not have the potential for neurological complications that may be associated with cerebral angiography. The risk associated with follow-up cerebral angiography may no longer justify its role in the assessment of radiosurgical results in the treatment of AVMs.

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Magnetic resonance imaging for detection of late meniscal tears in dogs following tibial tuberosity advancement for treatment of cranial cruciate ligament injury

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-13-08-0107 ◽

2014 ◽

Vol 27 (02) ◽

pp. 141-146 ◽

Cited By ~ 3

Author(s):

C. R. Lamb ◽

M. S. Tivers ◽

A. Li ◽

F. Taylor-Brown

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Mr Imaging ◽

Cruciate Ligament ◽

Meniscal Tear ◽

Ligament Injury ◽

Meniscal Tears ◽

Resonance Imaging ◽

Mr Images ◽

Cranial Cruciate Ligament

SummaryTo document the use of and to estimate the accuracy of magnetic resonance (MR) imaging for detection of late meniscal tears in dogs with cranial cruciate ligament injury treated with tibial tuberosity advancement (TTA).Medical records of dogs that had TTA followed by stifle MR imaging for suspected meniscal tear and subsequent arthrotomy were reviewed retrospectively. Magnetic resonance images were reviewed independently by an observer blinded to clinical information who classified menisci as torn, abnormal but intact, or normal. Magnetic resonance and surgical findings were compared.Eight stifles from large breed dogs were included. Six stifles had a medial meniscal tear identified in MR images and later confirmed surgically. In the remaining two stifles, the menisci appeared intact in MR images and no tear was identified at subsequent arthrotomy. Lateral menisci in all stifles appeared intact in MR images and were considered normal at surgery. Susceptibility artefacts associated with TTA implants were present in all images but did not adversely affect interpretation of intra-articular structures.Magnetic resonance imaging appears to be accurate for diagnosis of late meniscal tears. Artefacts associated with TTA implants did not prevent evaluation of critical intra-articular structures. Further investigation with MR imaging should be considered when late meniscal tear is suspected following TTA.

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Gd3+-DTPA-Meglumine-Anionic Linear Globular Dendrimer G1: Novel Nanosized Low Toxic Tumor Molecular MR Imaging Agent

ISRN Pharmaceutics ◽

10.1155/2013/378452 ◽

2013 ◽

Vol 2013 ◽

pp. 1-14 ◽

Cited By ~ 2

Author(s):

Tahmineh Darvish Mohamadi ◽

Massoud Amanlou ◽

Negar Ghalandarlaki ◽

Bita Mehravi ◽

Mehdi Shafiee Ardestani ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Citric Acid ◽

Magnetic Resonance ◽

Early Diagnosis ◽

Mr Imaging ◽

Contrast Media ◽

Cancer Treatment ◽

Diagnostic Methods ◽

Resonance Imaging ◽

Mr Images

Despite the great efforts in the areas of early diagnosis and treatment of cancer, this disease continues to grow and is still a global killer. Cancer treatment efficiency is relatively high in the early stages of the disease. Therefore, early diagnosis is a key factor in cancer treatment. Among the various diagnostic methods, molecular imaging is one of the fastest and safest ones. Because of its unique characteristics, magnetic resonance imaging has a special position in most researches. To increase the contrast of MR images, many pharmaceuticals have been known and used so far. Gadopentetate (with commercial name Magnevist) is the first magnetic resonance imaging contrast media that has been approved by the US Food and Drug Administration. In this study, gadopentetate was first synthesized and then attached to a tree-like polymer called dendrimer which is formed by polyethylene glycol core and surrounding citric acid groups. Stability studies of the drug were carried out to ensure proper synthesis. Then, the uptake of the drug into liver hepatocellular cell line and the drug cytotoxicity were evaluated. Finally, in vitro and in vivo MR imaging were performed with the new synthetic drug. Based on the findings of this research, connecting gadopentetate to dendrimer surface produces a stronger, safer, and more efficient contrast media. Gd(III)-diethylenetriamine pentaacetate-meglumine-dendrimer drug has the ability to enter cells and does not produce significant cytotoxicity. It also increases the relaxivity of tissue and enhances the MR images contrast. The obtained results confirm the hypothesis that the binding of gadopentetate to citric acid dendrimer produces a new, biodegradable, stable, and strong version of the old contrast media.

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A distinct phenotypic change in gliomas at the time of magnetic resonance imaging detection

Journal of Neurosurgery ◽

10.3171/jns/2008/108/4/0782 ◽

2008 ◽

Vol 108 (4) ◽

pp. 782-790 ◽

Cited By ~ 13

Author(s):

Taichang Jang ◽

Binulal Sathy ◽

Yi-Hua Hsu ◽

Milton Merchant ◽

Benjamin Recht ◽

...

Keyword(s):

Magnetic Resonance ◽

Mr Imaging ◽

Phenotypic Change ◽

In Utero Exposure ◽

Resonance Imaging ◽

Mr Images ◽

Cancer Aggressiveness ◽

Imaging Detection ◽

And Diffusion ◽

Sequential Appearance

Object Although gliomas remain refractory to treatment, it is not clear whether this characteristic is fixed at the time of its origin or develops later. The authors have been using a model of neurocarcinogenesis to determine whether a time exists during a glioma's evolution during which it is detectable but still curable, thus providing a justification for exploring the clinical merits of an early detection and treatment strategy. The authors recently reported the presence of 2 distinct cellular subsets, 1 expressing nestin and the other both glial fibrillary acidic protein (GFAP) and osteopontin (OPN), within all examined gliomas that developed after in utero exposure to ethylnitrosourea. Methods In this study, the authors used magnetic resonance (MR) imaging to assess when these 2 subpopulations appeared during glioma evolution. Results Using T2-weighted and diffusion-weighted MR imaging, the authors observed that gliomas grew exponentially once detected at rates that were location-dependent. Despite large differences in growth rates, however, they determined by correlating histochemistry with imaging in a second series of animals, that all lesions initially detected on T2-weighted images contained both subsets of cells. In contrast, lesions containing only nestin-positive cells, which appeared on average 40 days before detection on MR images, were not detected. Conclusions The sequential appearance of first the nestin-positive cells followed several weeks later by those expressing GFAP/OPN suggests that all gliomas arise through common early steps in this model. Furthermore, the authors hypothesize that the expression of OPN, a molecule associated with cancer aggressiveness, at the time of T2-weighted detection signals a time during glioma development when the lesion becomes refractory to treatment.

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Hemorrhage of cavernous malformations during pregnancy and in the peripartum period: causal or coincidence?

Neurosurgical FOCUS ◽

10.3171/foc.2006.21.1.13 ◽

2006 ◽

Vol 21 (1) ◽

pp. 1-4 ◽

Cited By ~ 31

Author(s):

Sam Safavi-Abbasi ◽

Iman Feiz-Erfan ◽

Robert F. Spetzler ◽

Louis Kim ◽

Seref Dogan ◽

...

Keyword(s):

Magnetic Resonance ◽

Mr Imaging ◽

Cesarean Section ◽

Lower Extremity ◽

Signal Intensity ◽

Mr Images ◽

Cavernous Malformations ◽

Peripartum Period ◽

Risk Of Hemorrhage ◽

Thoracic Lesion

✓There is growing evidence to suggest that pregnancy may increase the risk of hemorrhage from cavernous malformations (CMs). In the present case, a 21-year-old primigravida was admitted to the authors' neurosurgical service after a cesarean section. Three weeks before admission she had experienced rapidly progressive bilateral lower-extremity paresthesias. Spinal magnetic resonance (MR) imaging revealed the presence of an intramedullary thoracic lesion. On T2-weighted MR images, heterogeneous signal intensity with a rim of decreased intensity was demonstrated in the spine. The mass was successfully resected, and 1 year later the patient's symptoms had resolved completely. This is the fourth reported case of a spinal intramedullary CM that became symptomatic during pregnancy. The pathogenesis and management of this entity are reviewed.

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Using the T2-weighted magnetic resonance imaging signal intensity ratio and clinical manifestations to assess the prognosis of patients with cervical ossification of the posterior longitudinal ligament

Journal of Neurosurgery Spine ◽

10.3171/2010.3.spine09887 ◽

2010 ◽

Vol 13 (3) ◽

pp. 319-323 ◽

Cited By ~ 27

Author(s):

Lin-Feng Wang ◽

Ying-Ze Zhang ◽

Yong Shen ◽

Yan-Ling Su ◽

Jia-Xin Xu ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Spinal Cord ◽

Magnetic Resonance ◽

Mr Imaging ◽

Signal Intensity ◽

Intensity Ratio ◽

Clinical Manifestations ◽

Posterior Longitudinal Ligament ◽

Signal Intensity Ratio ◽

Resonance Imaging

ObjectThe aim of this study was to investigate the clinical significance of both the signal intensity ratio obtained from MR imaging and clinical manifestations on the prognosis of patients with cervical ossification of the posterior longitudinal ligament.MethodsThe authors retrospectively reviewed the records of 58 patients with cervical ossification of the posterior longitudinal ligament who underwent cervical laminoplasty from February 1999 to July 2007. Magnetic resonance imaging (1.5-T) was performed in all patients before surgery. Sagittal T2-weighted images of the cervical spinal cord compressed by the ossified posterior longitudinal ligament showed increased intramedullary signal intensity, whereas the sagittal images obtained at the C7–T1 disc levels were of normal intensity. The signal intensity ratio between regions of intramedullary increased signal intensity and the normal C7–T1 disc level was calculated based on the signal intensity values generated from the MR imaging workstation. Patients were divided into 3 groups according to their signal intensity ratio (high, intermediate, and low signal intensity groups).ResultsThere were significant differences between the 3 groups regarding recovery rate (p < 0.001), age (p = 0.022), duration of disease (p = 0.001), Babinski sign (p < 0.001), ankle clonus (p < 0.001), and both pre- and postoperative Japanese Orthopaedic Association score (p < 0.001). There was no significant difference in sex among the 3 groups (p = 0.391).ConclusionsPatients with low signal intensity ratios that changed on T2-weighted imaging experienced a good surgical outcome. Low increased signal intensity might reflect mild neuropathological alteration in the spinal cord and greater recuperative potential. An increased signal intensity ratio with positive pyramidal signs indicates less recuperative potential of the spinal cord and a poor surgical outcome.

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