Enhanced Magnetic Resonance Imaging Scans Research Articles

The application value of LAVA-flex sequences in enhanced MRI scans of nasopharyngeal carcinoma: comparison with T1WI-IDEAL.

Magnetic resonance imaging (MRI) staging scans are critical for the diagnosis and treatment of patients with nasopharyngeal cancer (NPC). We aimed to evaluate the application value of LAVA-Flex and T1WI-IDEAL sequences in MRI staging scans. Eighty-four newly diagnosed NPC patients underwent both LAVA-Flex and T1WI-IDEAL sequences during MRI examinations. Two radiologists independently scored the acquisitions of image quality, fat suppression quality, artifacts, vascular and nerve display. The obtained scores were compared using the Wilcoxon signed rank test. According to the signal intensity (SI) measurements, the uniformity of fat suppression, contrast between tumor lesions and subcutaneous fat tissue, and signal-to-noise ratio (SNR) were compared by the paired t-test. Compared to the T1WI-IDEAL sequence, LAVA-Flex exhibited fewer artifacts (P<0.05), better visualization of nerves and vessels (P<0.05), and performed superior in the fat contrast ratio of the primary lesion and metastatic lymph nodes (0.80 vs. 0.52, 0.81 vs. 0.56, separately, P<0.001). There was no statistically significant difference in overall image quality, tumor signal-to-noise ratio (SNR), muscle SNR, and the detection rate of lesions between the two sequences (P>0.05). T1WI-IDEAL was superior to LAVA-Flex in the evaluation of fat suppression uniformity (P<0.05). LAVA-Flex sequence provides satisfactory image quality and better visualization of nerves and vessels for NPC with shorter scanning times.

Diagnostic Value of Dynamic Enhanced Magnetic Resonance Imaging Combined with Serum CA15-3, CYFRA21-1, and TFF1 for Breast Cancer.

Objective To explore the diagnostic value of dynamic enhanced magnetic resonance imaging (MRI) combined with serum CA15-3, CYFRA21-1, and TFF1 for breast cancer. Methods By means of a retrospective study, 60 breast cancer patients treated in our hospital from January 2018 to December 2020 were selected as the breast cancer group, 60 patients with benign breast lesions were selected as the benign group, and 60 healthy individuals who received physical examination in our hospital in the same period were selected as the control group. All study subjects received dynamic enhanced MRI scan and serological tests, their serum CA15-3 and CYFRA21-1 levels were measured with the electrochemiluminescence instrument and original auxiliary reagent, and the TFF1 level was measured with enzyme-linked immunosorbent assay (ELISA). The MRI performance variation in breast lesion patients was analyzed, the serum CA15-3, CYFRA21-1, and TFF1 levels of study subjects were compared among the three groups, and the efficacy of single diagnosis by dynamic enhanced MRI, CA15-3, CYFRA21-1, or TFF1 as well as combined diagnosis was explored by ROC curves. Results Dynamic enhanced MRI showed that malignant lesion had obscure boundary, irregular margin, and heterogeneity after enhancement, and the time-signal intensity curve presented fast-in fast-out; the benign lesion had a clear boundary and smooth margin, 25 cases showed homogeneity after enhancement, and the time-signal intensity curve presented slow-in slow-out; the CA15-3, CYFRA21-1, and TFF1 levels were significantly different among the breast cancer group, benign group, and control group (33.81 ± 12.46 vs 19.02 ± 6.47 vs 9.55 ± 2.64, 4.08 ± 1.41 vs 1.96 ± 1.19 vs 0.99 ± 0.21, 1.39 ± 0.54 vs 1.04 ± 0.26 vs 0.89 ± 0.12, P < 0.05); 57 breast cancer patients were diagnosed by a combined examination, with a sensitivity of 95.0%, specificity of 83.3%, positive predictive value of 74.0%, negative predictive value of 97.1%, accuracy rate of 87.2%, and AUC (95%CI) = 0.892 (0.840–0.943), indicating a significantly higher diagnostic value of the combined examination than the single examination by CA15-3, CYFRA21-1, TFF1, or MRI. Conclusion Combining dynamic enhanced MRI with serum CA15-3, CYFRA21-1, and TFF1 has good efficacy in diagnosing breast cancer, which can be applied in clinical diagnosis of breast cancer.

Relationship between magnetic resonance imaging findings and prognosis of intracranial tuberculosis.

Intracranial tuberculosis (TB) is an intracranial infection caused by Mycobacterium tuberculosis. Magnetic resonance imaging (MRI), in particular enhanced MRI scan, has the ability to detect characteristic lesions of tuberculous meningitis or cerebral parenchymal TB. To analyze the relationship between MRI findings and prognosis of patients with intracranial TB. In this retrospective study, a total of 60 patients were confirmed with intracranial TB in the hospital from May 2019 to December 2020. All enrolled patients underwent TB-related laboratory examinations, cranial MRI, and contrast-enhanced MRI. Laboratory tests were analyzed and the relationship between clinical prognosis and cranial MRI features was evaluated. Of the 60 patients, 28 (46.67%) had disseminated TB complications, 20 (36.67%) had secondary TB complications, and the remaining 10 (16.66%) had lymphatic TB or spinal TB complications. Of the patients, 25 had good short-term prognosis and 35 had poor short-term prognosis; 44 patients had good long-term prognosis and 16 had poor long-term prognosis. The incidence of cerebral parenchymal tuberculomas on enhanced MRI was significantly higher in the group with good prognosis compared to that in the group with poor prognosis (P < 0.05). Logistic analysis suggested that hydrocephalus (odds ratio [OR] = 0.057, 95% confidence interval [CI] = 0.003-0.444; P = 0.018) and cistern involvement (OR = 0.100, 95% CI = 0.011-0.581; P = 0.017) were independent risk factors for poor short-term prognosis. MRI can display the pathological changes of intracranial TB in detail; hydrocephalus and cistern involvement were independent risk factors for poor short-term prognosis.

Signal Intensity Changes in the Dentate Nucleus and Globus Pallidus of Multiple Sclerosis Patients Undergoing Multiple Brain Magnetic Resonance Imaging with Gadolinium-Based Contrast Agents

Objective: To investigate the correlation between cumulative doses of gadolinium-based contrast agents and increased signal intensity (SI) in the dentate nucleus (DN) and globus pallidus (GP). Methods: Our retrospective trial involved 21 multiple sclerosis patients (11 women, 10 men; mean age: 39.21±10.24, range: 20 to 57 years) who underwent a serial number of multiple cranial magnetic resonance imaging (MRI) examinations in the radiology department of our tertiary care center. Average signal intensities on the DN, pons, GP and thalamus on unenhanced T1-weighted magnetic resonance images were taken into account. The signal intensity in the DN was proportioned to the signal intensity in the pons, whereas the signal intensity in GP to the signal intensity in the thalamus. Any relationship between the DN-to-pons or GP-to-thalamus signal intensity ratios and previous gadolinium-based contrast administrations was sought by means of repeated measures ANOVA. Results: Increases in both DN-to-pons and GP-to-thalamus signal intensity ratios displayed a significant correlation with previous administrations of gadolinium-based contrast agents (p&lt;0.001 for both). A remarkable increase was detected in DN-to-pons and GP-to-thalamus signal intensity ratios between the first and last MRI examinations (p&lt;0.001 for both). Conclusion: Our results support the association between increase in the SI of the DN and GP to the number of gadolinium-enhanced MRI scans in MS patients. The increase in T1 SI seems to be linked with the number of enhanced MRI scans.

Consensus on Contouring Primary Breast Tumors on MRI in the Setting of Neoadjuvant Partial Breast Irradiation in Trials

PurposeOur purpose was to present and evaluate expert consensus on contouring primary breast tumors on magnetic resonance imaging (MRI) in the setting of neoadjuvant partial breast irradiation in trials. Methods and MaterialsExpert consensus on contouring guidelines for target definition of primary breast tumors on contrast-enhanced MRI in trials was developed by an international team of experienced breast radiation oncologists and a dedicated breast radiologist during 3 meetings. At the first meeting, draft guidelines were developed through discussing and contouring 2 cases. At the second meeting 6 breast radiation oncologists delineated gross tumor volume (GTV) in 10 patients with early-stage breast cancer (cT1N0) according to draft guidelines. GTV was expanded isotropically (20 mm) to generate clinical target volume (CTV), excluding skin and chest wall. Delineations were reviewed for disagreement and guidelines were clarified accordingly. At the third meeting 5 radiation oncologists redelineated 6 cases using consensus-based guidelines. Interobserver variation of GTV and CTV was assessed using generalized conformity index (CI). CI was calculated as the sum of volumes each pair of observers agreed upon, divided by the sum of encompassing volumes for each pair of observers. ResultsFor the 2 delineation sessions combined, mean GTV ranged between 0.19 and 2.44 cm3, CI for GTV ranged between 0.28 and 0.77, and CI for CTV between 0.77 and 0.94. The largest interobserver variation in GTV delineations was observed in cases with extended tumor spiculae, blood vessels near or markers within the tumor, or with increased enhancement of glandular breast tissue. Consensus-based guidelines stated to delineate all visible tumors on contrast enhanced–MRI scan 1 to 2 minutes after contrast injection and if a marker was inserted in the tumor to include this. ConclusionsExpert-based consensus on contouring primary breast tumors on MRI in trials has been reached. This resulted in low interobserver variation for CTV in the context of a uniform 20 mm GTV to CTV expansion margin.

The signal feature of magnetic resonance imaging of mucosal associated lymphoma tissue lymphoma of the orbit

Objective To investigate the magnetic resonance imaging(MRI) signal characteristics of primary mucosal associated lymphoma tissue lymphoma of the orbit. Methods MRI signal characteristics of 10 cases of orbital mucosal associated lymphoma tissue lymphoma between Sep. 2010 and Aug. 2017 were retrospectively analysed. All cases were confirmed by clinicopathology. MRI plain scan was performed in 10 cases and among them enhanced MRI scan was performed in 8 cases. Results There were 5 cases of single nodule type and 5 cases of diffuse type.Two cases of single nodule type occurred in the eyelid, and 3 cases of single of nodule type occurred in the rear of the eyeball.The diffuse type occurred in the eye muscle, intermuscular space and retrobulbar.MRI signal, T1WI presented equal or slightly high signal, and T2WI presented equal or slightly high signal, and the signal was uniform. The lesion of 8 cases who underwent enhanced scanning presented moderate to severe uniform enhancement. Conclusion The primary orbital mucosal associated lymphoma MRI shows equal or slightly higher signal intensity on T1WI and equal or slightly higher signal intensity on T2WI, which is significantly enhanced by enhanced scanning and shows some characteristics of encircling eyeball growth. Key words: Orbit; Lymphoma, mucosal associated; Magnetic resonance imaging

Sequence and Observer Variability in Gadoxectic Acid-Enhanced MRI Lesion Measurements in Hepatocellular Carcinoma

The purpose of the study was to investigate interobserver and intersequence variability in measuring hepatocellular carcinoma on magnetic resonance imaging (MRI). Twenty treatment-naïve lesions on Gadoxetic Acid enhanced MRI scans from 20 patients were retrospectively measured by six reviewers with different levels of experience, twice, six weeks apart, on eight different MRI sequences, in randomized order. The sequences include arterial, hepatobiliary, transitional, portal venous, T2, and diffusion weighted images. The single longest diameter (SLD) and longest diameter perpendicular to the longest overall diameter were measured on axial images and products of diameters calculated in accordance to response evaluation criteria in solid tumors v1.1 and World Health Organization response criteria respectively. Lesion-wise intraclass correlation coefficients were used to estimate measurement agreement. All intraclass correlation coefficients were greater than 0.95. No substantive differences between SLD and products of diameters metrics. Means (∼2.8 mm, SLD) and standard deviations (∼2 mm, SLD) were similar across sequences and observers. Similarly, pairwise comparison between observers grouped by experience showed statistically significant differences, but the effect size was minor (∼2 mm). Arterial and HPB-weighted images had similar mean dimensions (2.76 cm) while the smallest mean was in the transitional phase (2.62 cm). A lesion was not measured on 140 occasions (7%), mostly in ADC. There is high interobserver and intersequence reliability despite small differences between observers based on experience level. Our results suggest that accurate measurements can be made on arterial phase despite the possibility of indistinct margins. Lesions, however, are more likely to be missed on diffusion-related sequences.

The characters of computed tomography and magnetic resonance imaging in adrenal oncoctyoma patients

Objective To summerize computed tomography(CT) and magnetic resonance imaging(MRI) appearances of the adrenal oncoctyoma(AOC), and to improve the diagnostic accuracy. Methods The 11 cases imaging materials of AOC confirmed by pathology from March 2006 to August 2017 were analyzed retrospectively.There were 3 males and 8 females, aged from 24 to 65 years old(mean 46.8 years). There were 11 cases with CT unenhanced scan in which 9 cases performed enhancing scan, 8 cases underwent unenhanced and enhanced MRI scan. Results Of 11 cases (13 lesions), 10 cases were singular, 1 was unilaterally multiple(3 lesions). 5 cases were located in the right side, 6 in the left side. 10 lesions presented oval, 3 were round. The diameters of all lesions ranged from 1.4 to 9.9 cm, with a mean of 3.9 cm. All lesions were shown well-defined soft-tissue density on plain CT scan, 69.2%(9/13)of whom were homogeneous, 30.8% were heterogenous. The CT value ranged from 32.6 to 48.6 HU, with a mean of 37.9 HU. In 9 cases, 5 masses were markedly enhanced, 2 were slightly enhanced and 2 were moderately enhanced, and all of them depicted prolongedly enhanced on triple-phase scan. The masses of 8 cases appeared isointensity or slightly hypointensity on T1WI, hyperintesity on fat-suppressed T2WI. The signal did not change on opposed-phase imaging. The lesions demonstrated heterogeneously prolonged enhancement to some degree on enhanced T1WI images. There was no peritumoral adjacent invasion, enlarged lymph nodes and metastasis. Conclusions AOC usually presents soft-tissue density on unenhanced CT, no changing on MRI opposed-phase images. The tumors are characterized by markedly heterogeneously prolonged enhanced on enhanced CT and MRI. Key words: Oncocytoma; Adrenal; Magnetic resonance imaging(MRI); Computed tomography(CT)

Predictive value of diffusion-weighted MRI for invasiveness of hilar cholangiocarcinoma

Objective To investigate the predictive value of diffusion-weighted (DW) magnetic resonance imaging (MRI) for invasiveness of hilar cholangiocarcinoma (HC). Methods The retrospective case-control study was conducted. The clinicopathological data of 65 HC patients who were admitted to the Sun Yat-sen Memorial Hospital from January 2012 to November 2017 were collected. Patients received DW MRI before treatment, and 2 senior imaging doctors analyzed imaging data and measured the apparent diffusion coefficient (ADC) for the primary lesions of HC. Observation indicators: (1) MRI situations of HC; (2) relationship between ADC and clinicopathological factors; (3) receiver operator characteristic (ROC) curve analysis; (4) treatment and follow-up situations. According to patients′ conditions, treatment plans were done within 2 weeks after MRI and patients underwent radical resection of HC. Follow-up using telephone interview was performed to detect tumor recurrence up to December 2017. Measurement data with normal distribution were represented as ±s, and comparisons between group and among group were respectively analyzed using the t test and one-way ANOVA. Spearman′s rank correlation was performed to analyze the relationship between ADC and clinicopathological factors. ROC curves assessed the diagnostic efficiency of ADC. Results (1) MRI situations of HC: MRI and magnetic resonanced cholangio-pancreatography (MRCP) in 65 patients showed varying degrees of soft rattan-like dilations of intrahepatic bile ducts and truncation signs of bile tracts in hepatic port. Of 65 patients, tumors in 23, 7 and 35 patients were respectively pedunculated type, polypoid type and infiltrating type. The pedunculated-type lesions of 23 patients presented as low signal on T1WI and slightly high signal on T2WI; after enhanced scans of MRI, pedunculated-type lesions of 7 patients demonstrated moderate homogenous enhancement in 3 patients, ring-like enhancement with internal liquefaction necrosis in 10 patients and moderate heterogeneous enhancement in 10 patients, respectively. The polypoid-type lesions presented as low signal on T1WI and high signal on T2WI, and moderate homogenous enhancement by enhanced scans of MRI. There were varying degrees of bile duct wall thickness and irregular nodules in the infiltrating-type lesions of 35 patients, showing moderate enhancement by enhanced scans of MRI. All the lesions of 65 patients using DW MRI demonstrated restricted diffusion, showing a clear boundary between lesions and normal surrounding bile ducts or liver tissues; heterogeneous enhancement lesions by MRI scans presented as heterogeneously high signal on DWI and heterogeneously low signal on ADC map, and necrotic area of lesions showed low signal on DWI; homogenous enhancement by MRI scans presented as homogenously high signal on DWI and homogenously low signal on ADC map. (2) Relationship between ADC and clinicopathological factors: ADC was respectively (1.382±0.165)×10-3 mm2/s, (1.343±0.138)×10-3 mm2/s, (1.291±0.226)×10-3 mm2/s, (1.111±0.243)×10-3 mm2/s in stage Ⅰ, Ⅱ, Ⅲ and Ⅳ (TNM staging) and (1.441±0.355)×10-3 mm2/s, (1.226±0.177)×10-3 mm2/s, (1.061±0.228)×10-3 mm2/s in high-differentiated, moderate-differentiated and low-differentiated tumors (pathological grading) and (1.403±0.176)×10-3 mm2/s, (1.121±0.238)×10-3 mm2/s in Ki-67 score ≤10% and >10% and (1.115±0.241)×10-3 mm2/s, (1.347±0.174)×10-3 mm2/s in HC patients with and without lymph node metastasis, with statistically significant differences in the above indicators (F=4.158, 9.866, t=11.607, 13.464, P 10% were 66.7% and 75.0%, and area under ROC curve was 0.783 (95%CI: 0.62-0.90, P<0.05). Using 1.222×10-3 mm2/s as a critical value of ADC, the sensitivity and specificity of ADC in the diagnosis of lymph node metastasis were 91.3% and 71.4%, and area under ROC curve was 0.873 (95%CI: 0.76-0.94, P<0.05). (4) Treatment and follow-up situations: 65 patients underwent successful radical resection of HC. Thirty-three patients were followed up for 1-24 months. Of 33 patients, 5 had tumor recurrence within 6 months postoperatively, including 4 with ADC < 1.100×10-3 mm2/s, 13 had tumor recurrence after 6 months postoperatively, and 15 didn′t have tumor recurrence or metastasis, including 1 with ADC <1.100×10-3 mm2/s. Conclusions There are different ADC in different TNM staging, pathological grading, Ki-67 score and with or without lymph node metastasis of HC. ADC of DW MRI can be used as a preoperative imaging predictor for invasiveness of HC. Key words: Hilar cholangiocarcinoma; Bile tract neoplasms, hilar; Magnetic resonance imaging; Diffusion weighted imaging; Apparent diffusion coefficient; Invasiveness

Computed tomography and magnetic resonance imaging features of the myomatous hepatic angiomyolipoma

Objective To investigate the computed tomography (CT) and magnetic resonance imaging (MRI) features of the myomatous hepatic angiomyolipoma (MHAML). Methods The retrospective cross-setional study was conducted. The clinicopathological data of 22 patients with MHAML who were admitted to the Southwest Hospital of the Third Military Medical University between January 2010 and June 2016 were collected. Patients underwent plain and enhanced scans of CT and MRI, and then received pathological examination after surgical resection or liver puncture and immunohistochemical staining. Observation indicators: (1) findings of CT and MRI, 2 radiologists independently read films; (2) diagnostic consistency of 2 radiologists; (3) results of pathological examination. The Kappa test was used for evaluating the consistency, κ≥0.75 as a good consistency, 0.40<κ<0.75 as a normal consistency and κ≤0.40 as a poor consistency. Results (1) Findings of CT and MRI: of 22 patients, 16 received CT scans and 6 received CT and MRI scans. Tumors of 22 patients were single lesion, showing similar-circular type. Tumors located in the right liver lobe, left liver lobe and caudate lobe were respectively detected in 14, 7 and 1 patients. ① Plain and enhanced scans of CT: tumors of 22 patients showed low density. Twenty patients had clear boundary of tumor and 2 had an unclear boundary. Tumors of 22 patients demonstrated obvious enhancement in arterial phase by enhanced scans of CT, including fast-in and slow-out enhancement in 10 patients and fast-in and fast-out enhancement in 12 patients. The draining veins inside tumors were detected in 12 patients in early arterial phase by enhanced scans of CT. The dilated blood vessels inside tumors were found in 12 patients. The ring enhancement of tumor margin was detected in 16 patients, with formation of small blood vessels involving tumor blood supply. ② MRI scan: tumors of 6 patients presented as low signal on T1WI and high signal on T2WI. Of 6 patients, 5 had clear boundary of tumor and 1 had an unclear boundary. Tumors of 6 patients demonstrated obvious enhancement in arterial phase by enhanced scans of MRI, with a fast-in and fast-out enhancement. The draining veins inside tumors were detected in 3 patients in early arterial phase by enhanced scans of MRI. The dilated blood vessels inside tumors were found in 1 patient. The persistent ring enhancement of tumor margin was detected in 5 patients, with formation of small blood vessels. All the lesions of 6 patients using GD-EOB-DTPA MR contrast-enhanced scan demonstrated restricted diffusion with a high b value (b=800 s/mm2), an average apparent diffusion coefficient of 1.549×10-3 mm2/s (1.209×10-3-1.796×10-3 mm2/s) and low a signal in liver phase. (2) Diagnostic consistency of 2 radiologists: there were good diagnostic consistencies of 2 radiologists in tumor location, density, T1WI, T2WI, bleeding, enhancement method and dilated blood vessels (κ=1.00, 1.00, 1.00, 1.00, 0.82, 0.82, P<0.05). There were normal diagnostic consistencies of 2 radiologists in tumor fat, calcification, component of cystolization, boundary, draining veins and enhancement of tumor margin (κ=0.46, 0.45, 0.64, 0.54, P<0.05). (3) Results of pathological examination: results of pathological examination of tumors from surgical resection of 17 patients and liver puncture of 5 patients showed that smooth muscle cells were the major components, and thick-walled vessels were found in the tumor of 12 patients. Results of immunohistochemical staining showed that anti melanoma specific monoclonal antibody (HMB-45) was positive. Conclusion The persistent enhancement of tumor margin, draining veins in early arterial phase by enhanced scans and dilated blood vessels might play roles in diagnosis of MHAML. Key words: Liver neoplasms; Angiomyolipoma; Myomatous type; Tomography, X-ray computed; Magnetic resonance imaging; GD-EOB-DTPA

Three-dimensional arterial spin labeling imaging and dynamic susceptibility contrast perfusion-weighted imaging value in diagnosing glioma grade prior to surgery.

The current study aimed to investigate whole-brain three-dimensional arterial spin labeling imaging (3D ASL) and dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI), in regards to their diagnostic value of preoperative glioma grade. The parameter values obtained after correction will be correlated with the diagnostic value of 3D ASL and DSC-PWI perfusion. In the current study, 50 patients with gliomas confirmed by pathology were used, including 27 low-grade gliomas (LGGs) and 23 high-grade gliomas (HGGs). Prior to surgery all patients underwent 3 Tesla magnetic resonance imaging (MRI), 3D ASL, DSC-PWI and conventional enhanced MRI scans to obtain original 3D ASL and DSC-PWI images, and the tumor regions with the most obvious parenchyma perfusion and contralateral normal white matter were selected. In these areas, the ASL-relative cerebral blood flow (ASL-rCBF), DSC-relative cerebral blood flow (DSC-rCBF) and DSC-relative cerebral blood volume (DSC-rCBV) parameter values were then obtained after correction for individual differences. The results of the present study show that ASL-CBF, DSC-CBF, DSC-CBV values and ASL-rCBF, DSC-rCBF, DSC-rCBV values increased as the grade of the glioma being imaged increased, and there was a marked difference between the HGGs and the LGGs. ASL-rCBF was significantly positively correlated with DSC-rCBF (r=0.580, P<0.01). In addition, ASL-rCBF was significantly positively correlated with DSC-rCBV (r=0.431, P<0.01). Receiver operating characteristic (ROC) curves were applied to compare the two perfusion parameters of DSC-PWI and 3D ASL in the diagnosis of glioma grade. ASL-rCBF had the highest area value under the ROC curve (0.836). The areas under the ROC curve of DSC-rCBF and DSC-rCBV were analyzed using the Z test, but the difference was not statistically significant. When ASL-rCBF, DSC-rCBF and DSC-rCBV were cutoff at 2.24, 1.85 and 1.68, the sensitivity of HGG diagnosis was 83.2, 91.3 and 91.3%, and the specificity was 77.7, 63.9 and 66.7%, respectively.

Imaging features of surgical complications of Crohn′s disease

Imaging features of surgical complications of Crohn′s disease

Imaging features of intestinal-type and pancreaticobiliary-type invasive adenocarcinoma of the ampullary region

Objective To analyze the computed tomography (CT) and magnetic resonance imaging (MRI) features of intestinal-type and pancreaticobiliary-type invasive adenocarcinomas of the ampullary region (IAARs) and investigate the value of the differential diagnosis. Methods The retrospective cross-sectional study was adopted. The clinicopathological data of 33 patients with IAAR who were admitted to the Lanzhou University Second Hospital (20 patients) and Affiliated Hospital of Ningbo University (13 patients) between September 2013 and August 2015 were collected. The patients underwent plain and enhanced scans of CT and MRI. (1) Observation indictors included tumor size, shape, growth pattern, boundary, internal structure, density and/or signal, style and/or degree of contrast enhancement, changes of bile and/or pancreatic duct, invasion and metastasis. (2) The clinical and imaging features of intestinal-type and pancreaticobiliary-type IAARs were compared. (3) Operation was performed after preoperative examinations, and patients received the postoperative pathological examination and immunohistochemistry. Measurement data with normal distribution were presented as ±s. Comparison between groups was evaluated with an independent sample t test, and count data were analyzed using the chi-square test. Results (1) Of 33 patients with IAAR, 19 received plain scan of CT, including 17 receiving simultaneous enhanced scan of CT. Fourteen patients [9 receiving diffussion-weighted imaging (DWI) sequence of MRI] received plain scan of MRI, including 12 receiving simultaneous enhanced scan of MRI. The maximum diameter of IAAR in 33 patients was (2.8±1.4)cm. Fourteen tumors were round-like or oval shape and 19 tumors were irregular shape. The intracavity type, extracavity type and mixed type of tumors were detected in 24, 6 and 3 patients, respectively. There were clear boundary of tumors in 17 patients and fuzzy boundary of tumors in 16 patients. Tumors of 5 patients had appeared necrotic and/or cystic, no hemorrhage or calcification was found in tumors of 33 patients. Density and signal of tumors were homogeneous in 18 patients and inhomogeneous in 15 patients. Of 29 patients receiving enhanced scan of CT or MRI, homogeneous enhancement and inhomogeneous enhancement were respectively detected in 14 and 15 patients, and mild enhancement, moderate enhancement and no enhancement were respectively detected in 15, 14 and 0 patients. Tumors of 9 patients in DWI showed slightly high or high signal. Thirty patients had secondary bile duct dilatation (3 with mild dilatation, 6 with moderate dilatation and 21 with severe dilatation), and 3 patients had no changes of bile duct. Twenty-six patients had secondary pancreatic duct dilatation and 7 had no changes of pancreatic duct. Sixteen patients had tumor invasion to pancreatic tissues and 7 had lymph node metastases. (2) Of 33 patients with IAAR, 19 had intestinal-type IAAR (8 males and 11 females) and 14 had pancreaticobiliary-type IAAR (11 males and 3 females). There was statistically significant difference in the gender between the 2 types of IAAR (χ2=4.388, P<0.05). The intracavity type, extracavity type and mixed type of tumors, clear boundary and fuzzy boundary of tumors, homogeneous and inhomogeneous density and/or signal of tumors, with and without tumor invasion to pancreatic tissues were respectively detected in 17, 0, 2, 13, 6, 14, 5, 6, 13 patients with intestinal-type IAAR and 7, 6, 1, 4, 10, 4, 10, 10, 4 patients with pancreaticobiliary-type IAAR, with statistically significant differences between the 2 types of IAAR (χ2=9.971, 5.125, 6.617, 5.125, P<0.05). (3) All the patients underwent surgery and received comprehensive diagnosis and tumor classification after pathological examination and immunohistochemistry. Conclusion There are certain characteristics of CT and MRI in intestinal-type and pancreaticobiliary-type IAARs, and gender, tumor growth pattern, boundary, density and/or signal, tumor invasion to pancreatic tissues have certain reference values for the differential diagnosis of intestinal- type and pancreaticobiliary-type IAARs. Key words: Ampullary neoplasms; Invasive adenocareinoma; Tomography, X-ray computed; Magne-tic resonance imaging

Dynamic contrast-enhanced MRI serves as a predictor of HIFU treatment outcome for uterine fibroids with hyperintensity in T2-weighted images.

The aim of the present study was to investigate the efficacy of dynamic contrast-enhanced magnetic resonance imaging (MRI) in predicting the outcome of using ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation for the treatment of uterine fibroids with T2 hyperintensity under MRI. A total of 131 uterine fibroids from 131 patients that appeared hyperintense under T2-weighted MRI were analyzed. The uterine fibroids were subjectively categorized into slight, irregular or regular enhancement groups, according to pretreatment dynamic contrast-enhanced MRI in the arterial phase within 60 sec after the injection of gadolinium. The non-perfused volume (NPV), which is indicative of successful ablation, was represented as the non-perfused area inside the uterine fibroids on enhanced MRI scans following treatment. Additionally, the treatment duration, treatment efficiency, sonication duration, energy efficiency ratio and any adverse events were recorded. The results indicated that the average NPV ratio for all the treated fibroids was 68.5%, while the average NPV ratios for fibroids with slight, irregular or regular enhancement were 84.7, 70.6 and 57.1%, respectively. Fibroids with regular enhancement were associated with the lowest NPV ratio and the lowest treatment efficiency, but exhibited the highest energy effect ratio and an elevated risk of severe adverse effects. The results of the present study indicate that hyperintense uterine fibroids with slight and irregular enhancement in the arterial phase of dynamic contrast-enhanced MRI are suitable for USgHIFU treatment. By contrast, uterine fibroids with regular enhancement were associated with the lowest treatment efficacy and safety.

Radiological and clinical findings of osseous peripheral primitive neuroectodermal tumors.

Peripheral primitive neuroectodermal tumor (pPNET) is a rare and highly malignant undifferentiated type of tumor. The aim of the present study was to analyze the computed tomography (CT), magnetic resonance imaging (MRI) and clinical findings of osseous pPNET. The present study retrospectively analyzed the clinical data and CT findings from 15 patients with osseous pPNET; the MRI findings from 11 of these 15 patients were confirmed by histopathological examination. The 15 patients included 9 men and 6 women. The mean patient age was 29 years (range, 16-64 years) and 11 cases were aged <30 years. A CT scan was performed in 15 cases and the findings included a lytic lesion (13 cases), a lytic lesion with irregular sclerosis and dilation (2 cases), a soft tissue mass (15 cases), calcification (2 cases) and periosteal reaction (5 cases). A total of 9 cases of soft tissue mass were heterogeneous, with different sizes of lower-density necrotic areas. An enhanced MRI scan was performed in 11 cases. On T1-weighted images (WI), the soft tissue mass was isointense (8 cases) and marginally hyperintense (3 cases). On T2WI, aggressive soft tissue masses were heterogeneous iso- or hyperintense (11 cases). On contrast-enhanced T1WI, marked heterogeneous enhancement was present in 10 cases and intermediate heterogeneous enhancement in 1 case. The results indicated that osseous pPNET mainly affects male adolescents and young adults. The CT findings of osseous pPNET were destructive lesions with a soft tissue mass and, occasionally, with periosteal reaction. The tumor was often isodense, with patchy hypodense areas. Tumor calcification was uncommon. The MRI findings were those of an aggressive soft tissue mass exhibiting isointensity on T1WI and iso- or hyperintensity on T2WI, with marked heterogeneous enhancement. Although the imaging characteristics of pPNETs may be non-specific, CT and MRI may be useful in delineating the extent of the tumor, identifying distant metastases, predicting resectability and monitoring treatment.

Progressive increase of T1 signal intensity of the dentate nucleus on unenhanced magnetic resonance images is associated with cumulative doses of intravenously administered gadodiamide in patients with normal renal function, suggesting dechelation.

The purpose of this study was to assess the association between the serial number of gadolinium-enhanced magnetic resonance imaging (MRI) examinations and the signal hyperintensity of the dentate nucleus on unenhanced T1-weighted images in patients with multiple sclerosis (MS) and those with brain metastases (BMs). A group of 38 patients with MS and 37 patients with BM who had undergone at least 2 consecutive enhanced MRI examinations in our institution were examined for this retrospective observational study. The average T1 signal intensity of the dentate nuclei and the pons was obtained, and the dentate nuclei-to-pons (DNP) signal intensity ratio was calculated. These values were compared between patients with less than 6 and 6 enhanced MRI scans or more (eMRI). Relative changes of the DNP were plotted against the number of enhanced MRI scans (eMRIn). A progressive increase in the T1 signal intensity of the DNP ratio was observed both in the MS group and in the BM group. The DNP ratios of the last eMRI scans in the subgroup of patients with 6 eMRI scans or more were significantly higher than those of the first eMRI scan in the MS group (P < 0.001) and in the BM group (P < 0.01). Relative changes of the DNP showed a positive correlation with the eMRIn with a Spearman ρ of 0.96 (P < 0.001) in the MS group and that of 0.88 (P < 0.001) in the BM group. Curve regression analyses of the relative change of DNP ratios showed linear models to best fit the data with r(2) of 0.89 in the MS group and r(2) of 0.74 in the BM group. Our study shows that the increase in the unenhanced T1 signal intensity has a linear relationship with the eMRIn in patients with MS and BM. Indeed, we estimated a linear regression model to fit the progressive increase in T1 signal intensity of the dentate nucleus after multiple enhanced MRI scans. This finding suggests substantial dechelation of gadodiamide in patients with normal renal function, raising further concerns regarding the stability of this agent. Further comparative studies with other gadolinium chelates, specifically both linear and macrocyclic, are strongly recommended.

Extraskeletal myxoid chondrosarcoma: A report of two cases.

Extraskeletal myxoid chondrosarcoma (EMC) is a relatively rare but well-defined neoplasm. This report describes two patients, one with EMC of the buttock and one with EMC of the knee. The two cases presented with large lobed masses and long T1 and T2 signaling identified by magnetic resonance imaging (MRI). An enhanced MRI scan demonstrated enhancement of the tumors. The tumors were composed of strands or cords of oval and spindle cells embedded in abundant myxoid stroma. Pathology results confirmed EMC.

Ablation targets in reentrant ventricular tachycardia

Introduction Magnetic resonance imaging (MRI) with late gadolinium enhancement has been used to pinpoint myocardial infarction features in animal models. In swine postinfarction, this imaging technique has been used to identify areas with slow conduction during reentrant ventricular tachycardia (VT). In this model, the reentry isthmus is composed of a small volume of viable myocardium bounded by scar tissue laterally and at depth. During reentrant VT, arcs of conduction block form where scar is present. In proximity to the infarct, the enhanced MRI scan shows a mixture of electrically conducting viable myocardium and nonviable tissue where conduction is slow during VT. The region is termed the heterogeneous zone (HZ) and appears gray in the contrast-enhanced images, as compared with the white infarct scar and dark gray or black normal myocardium. More recently, the relationship between HZ characteristics and reentrant VT inducibility was shown in swine postinfarction. The authors tested the hypothesis that by ablating the HZ in its entirety, reentrant VT would no longer be inducible, whereas when ablation was incomplete, reentrant VT would still be inducible, though possibly with a differing reentrant circuit morphology. They found that only when the HZ was entirely ablated did the reentrant VT become noninducible. In a new study on this topic, published in this issue of HeartRhythm, the feasibility of using the contrastenhanced imaging in postinfarction VT patients to target arrhythmogenic regions before electrophysiologic (EP) study and radiofrequency ablation is assessed.

Magnetic Resonance Imaging Characteristics and Surgical Results of Adrenocorticotropin-Secreting Pituitary Adenomas

To evaluate magnetic resonance imaging (MRI) characteristics and surgical results of adrenocorticotropin (ACTH)-secreting pituitary adenomas. MRI characteristics and relationship between MRI positive rate and surgical results of 266 patients with pathologically confirmed Cushing's disease were analyzed retrospectively. All patients underwent thin-section sagittal and coronal scans of the pituitary gland before and after administration of gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) on a 1.5 Tesla MRI scanner, and dynamic enhanced MRI was performed in 39 patients. All patients underwent transsphenoidal adenomectomy. Endocrinological examinations and assessments were performed. Preoperative MRI revealed normal results in 41 (15.4%) cases, microadenoma in 179 (67.3%), macroadenoma in 42 (15.8%), and huge adenoma in 4 (1.5%). Pituitary apoplexy was found in 13 (4.9%) cases. Positive rate of ACTH-secreting adenomas was 84.6% (225/266) on MRI scans, and that of small microadenomas was 87.2% (34/39) on dynamic enhanced MRI scans. Preoperative endocrinological tests of 199 cases supported the diagnosis of typical Cushing's disease, while the other 67 cases had atypical endocrinological results. The endocrinological cure rate, remission rate, and inefficacy rate were 85.7%, 7.9%, and 6.4%, respectively. There was no difference in the initial endocrinological cure rate between the patients with positive and normal MRI results (90% vs. 87.8%, P = 0.904). Enhanced coronal pituitary MRI is helpful for preoperative localization of ACTH-secreting pituitary microadenoma. Dynamic enhanced MRI may improve detection rate of microadenoma. There is no marked difference in the surgical results for patients with preoperative MRI results indicating presence or absence of microadenoma.

Transsphenoidal surgery for Cushing disease: results of our experience in 39 consecutive patients

To evaluate magnetic resonance imaging (MRI) characteristics and surgical results of adrenocorticotropin (ACTH)-secreting pituitary adenomas.MRI characteristics and relationship between MRI positive rate and surgical results of 266 patients with pathologically confirmed Cushing's disease were analyzed retrospectively. All patients underwent thin-section sagittal and coronal scans of the pituitary gland before and after administration of gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) on a 1.5 Tesla MRI scanner, and dynamic enhanced MRI was performed in 39 patients. All patients underwent transsphenoidal adenomectomy. Endocrinological examinations and assessments were performed.Preoperative MRI revealed normal results in 41 (15.4%) cases, microadenoma in 179 (67.3%), macroadenoma in 42 (15.8%), and huge adenoma in 4 (1.5%). Pituitary apoplexy was found in 13 (4.9%) cases. Positive rate of ACTH-secreting adenomas was 84.6% (225/266) on MRI scans, and that of small microadenomas was 87.2% (34/39) on dynamic enhanced MRI scans. Preoperative endocrinological tests of 199 cases supported the diagnosis of typical Cushing's disease, while the other 67 cases had atypical endocrinological results. The endocrinological cure rate, remission rate, and inefficacy rate were 85.7%, 7.9%, and 6.4%, respectively. There was no difference in the initial endocrinological cure rate between the patients with positive and normal MRI results (90% vs. 87.8%, P = 0.904).Enhanced coronal pituitary MRI is helpful for preoperative localization of ACTH-secreting pituitary microadenoma. Dynamic enhanced MRI may improve detection rate of microadenoma. There is no marked difference in the surgical results for patients with preoperative MRI results indicating presence or absence of microadenoma.