Comparison of rectilinear scanning and scintiphotography for the detection of brain lesions

Summary Technetium brain scans and scintiphotos made in a series of 300 patients, harbouring 100 brain lesions, were blindly reviewed and compared. The overall accuracy of the original readings had been 84.5%. — In this series scanning turned out to be more reliable than scintiphotography, either with or without the use of a 1600-channel analyzer, although in a few cases the reverse was true. — Photoscope images, apart from their size and translucency, were found to be no gain. Multichannel analyzing is an advantage, but has not yet made scanning dispensable. We recommend that every negative camera study be followed by conventional scintigraphy.

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Vergleich von Hirnszintigraphie und Szinti-Fotografle bei cerebralen Läsionen

Zusammenfassung Bei 300 Patienten (davon 100 Kranke mit cerebralen Läsionen) wurde eine Hirnszintigraphie und eine Szinti-Fotografie durchgeführt und ohne Kenntnis klinischer Daten ausgewertet. Dabei betrug die diagnostische Genauigkeit 84,5%. In der vorliegenden Untersuchungsserie ergab die Szintigrafie die zuverlässigeren Resultate. Es wird gefordert, daß jedes negative Ergebnis der Gamma-Kamera durch die Szintigraphie kontrolliert werden sollte.

     

Comparison of inversion recovery fast spin-echo (FSE) with T2-weighted fat-saturated FSE and T1-weighted MR imaging in bone marrow lesion detection

 Objective To prospectively compare inversion recovery (IR) fast spin-echo (FSE) with T1-weighted spin-echo (SE) and T2-weighted chemical-shift fat-saturated (FS) FSE magnetic resonance sequences in the detection of bone marrow abnormality. Design. Twenty-nine sets of T1-weighted SE [400–640/10–20 (TR/TE)], T2-weighted FS-FSE [2400–3800/91–112/8 (TR/TE/ETL)], and IR-FSE [3700–6000/12–14/170/8 (TR/TE/T1/ETL)] images were acquired with a 1.5-T magnet in 27 patients with bone marrow lesions. The visibility, margination, and extent of 41 lesions, image quality, contrast, and artifacts were qualitatively and quantitatively compared. Results. The lesions were more conspicuous on the IR-FSE than on the T1-weighted SE and T2-weighed FS-FSE images. The extent of lesions was similar for all three sequences. Image quality was better and there were fewer motion artifacts on the T1-weighted images. The mean lesion contrast-to-noise ratio was significantly higher on the T1-weighted images (p<0.05). Conclusion. The IR-FSE sequence is highly sensitive for detecting bone marrow pathology, with scan time comparable to the T1-weighted SE and T2-weighted FS-FSE sequences.     

Initial feasibility studies using single-shot EPI for the detection of focal liver lesions

Echo planar MR imaging (EPI) has been developed to completely eliminate motion artifacts and is currently being prepared for implementation into clinical MR systems. Thus, the purpose of this study was to evaluate the clinical utility of EPI in the detection of focal liver lesions and to compare EPI with contrast-enhanced CT. EPI studies were performed on an experimental 1.0 Tesla whole body system using fat-suppressed single-shot spin echo (SE) and inversion recovery (IR) pulse sequences. A total of 26 liver tumors in 12 patients scheduled for liver resection were prospectively examined and correlated with intraoperative ultrasound, surgery, and pathology as the gold standard. Quantitative analysis of EPI was performed by means of liver signal-to-noise and tumorliver contrast-to-noise calculations. Diagnostic performance compared with contrast-enhanced CT was assessed by means of ROC analysis. Lesion-liver contrast was highest with EPI SE at a TE-time of 70 ms and this technique showed best lesion detectability as measured by area under curve (AUC) values. Among EPI techniques, the IR sequence with an inversion time of 300 ms to null the liver signal showed high lesion-liver contrast but all four reviewers reported problems assessing liver anatomy. Improved EPI techniques may prove useful for screening of focal liver lesions.     

Gadobenate dimeglumine-enhanced liver MR imaging: value of dynamic and delayed imaging for the characterization and detection of focal liver lesions

The aim of this study was to determine the value of delayed-phase imaging (DPI) of gadobenate dimeglumine (Gd-BOPTA)-enhanced MR imaging for the evaluation of focal hepatic tumors compared with precontrast imaging and early dynamic phase imaging. The MR images were obtained in 48 patients with 98 focal hepatic tumors. Three-dimensional gradient-echo (GRE) imaging obtained before and 30, 60, and 1 h after administration of 0.1 mmol/kg of gadobenate dimeglumine. Each image set was analyzed qualitatively (lesion detection, conspicuity, delineation, and enhancement pattern on DPI) and quantitatively [signal-to-noise ratio (SNR), tumor–liver contrast-to-noise ratio (CNR)]. Improved lesion-to-liver contrast during the dynamic phase imaging was observed compared with precontrast images. The DPI showed a homogeneous enhancement of liver parenchyma and distinctive enhancement features of focal liver lesions: metastases (85%) showed a target shaped enhancement, and hepatocellular carcinomas (HCCs) showed an inhomogeneous (58%) or homogeneous enhancement (21%). The DPI showed better performance for the detection of metastases than other images by increasing lesion delineation (p<0.05). The absolute CNR of metastasis measured from periphery of the tumors on DPI was greater than precontrast and arterial phase imaging (p<0.05). The Gd-BOPTA during both dynamic and delayed phases provides valuable information for the characterization of focal liver lesions, and furthermore, Gd-BOPTA-enhanced DPI contributed to the improved detection of liver metastasis compared to precontrast and early dynamic imaging.     

Safety and efficacy of Mangafodipir trisodium in patients with liver lesions and cirrhosis

Mangafodipir trisodium (Mn-DPDP, Teslascan) is a well-tolerated liver contrast agent. Although the enhancement characteristics of the cirrhotic liver after Mangafodipir trisodium administration have been studied, at present there is no published data on the impact that cirrhosis might have on the safety and efficacy profiles of this agent. Our objective is to evaluate by means of a retrospective comparison the safety and efficacy of Mangafodipir trisodium in patients with underlying cirrhosis who were examined for suspicion of focal liver lesions. A total of 923 patients received Mangafodipir trisodium (5 μmol/kg) in 11 prospective randomized European clinical trials. Adverse events and discomfort were recorded and graded in all patients. The efficacy analyses were performed on the subsets consisting of 617 patients with independent lesion counts (detection), and on the subset with 399 patients with independent and onsite final lesion diagnosis (characterization). Of the 399 patients, 149 had histologic confirmation. One hundred eighty of 923 patients (19.5%) had cirrhosis. There were no main differences between cirrhotic and non-cirrhotic patients. Adverse events were observed in 64 patients (6.9%), 6.7% in the cirrhotic group and 7.0% in the non-cirrhotic group, a non-significant difference. Adverse events in most patients were mild or moderate. The presence and intensity of the events did not differ between groups. Discomfort was recorded in 79 patients (8.6%), equally distributed in cirrhotic (6.1%) and non-cirrhotic (9.2%) patients. Regarding lesion count, significantly more lesions were found in the post- than in the precontrast images in both the cirrhotic and non-cirrhotic groups (p<0.0001). This increase was not influenced by the presence of liver cirrhosis (p=0.94). Lesion characterization was significantly improved in cirrhotic patients after administration of Mangafodipir trisodium (p=0.002) but not in non-cirrhotic patients (p=0.13). Mangafodipir trisodium is a safe and well-tolerated useful contrast agent in patients with cirrhosis.     

Comparison of mammography and transillumination light scanning in the detection of breast lesions

A prospective study was done involving 822 women who had both film screen mammography and a breast transillumination light scan examination. The study population was not randomized; a modified phase-2 study was done. Mammography was superior for detecting malignancy: of the 67 pathologically proved breast cancers, 64 (95.5%) were detected by mammography and 45 (67.2%) were detected by transillumination. Biopsy revealed that 74 patients had benign lesions. In this group of patients, the false-positive rate was 12.2% for light scanning and 79.7% for mammography; however, 117 other patients had false-positive light scans.     

FSE和GRE T2加权像在颈椎检查中的对比

在颈椎的磁共振成像（MRI）中,快速自旋回波（fast spin echo,FSE)为其提供了检查时间短,形态结构清晰的优越性,而梯度回波(gradient echo,GRE)成像技术可产生更强的信号,更高的清晰度和敏感度。本文对二者矢状位和横轴位T2加权像进行了比较,提出了颈椎MRI最佳的检查方法。     

The role of SPIO-enhanced MRI in the detection of malignant liver lesions

The aim of this study was to evaluate the efficacy of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) in the detection of malignant liver tumors. MRI, using fast spin-echo T₂-weighted and gradient-echo T₁-weighted imagings before and after SPIO infusion, was performed in 32 patients with known or suspected hepatic lesions. Statistical analysis was performed using lesion-by-lesion analysis. SPIO-enhanced T₂-weighted MRI showed results comparable to those of unenhanced T₂-weighted MRI in the detection of focal liver lesions.     

Benign liver lesions: implications of detection in cancer patients

A review of liver sonograms obtained for cancer patients (excluding primary liver cancers) over a 12 year period found 829 benign lesions: non-parasitic cysts (427 cases), hemangiomas (216 cases), solitary calcifications (79 cases), focal fatty infiltration (62 cases), and miscellaneous lesions (45 cases). These benign pathologies represented 41.8% of the focal hepatic lesions observed during this period in this population; hepatic metastases accounted for the remaining 58.2%. Marked female predilection was noted for the nonparasitic cysts, hemangiomas, and focal fatty infiltration; 63–78.7% of these lesions were solitary, and first-line imaging by US was sufficient for diagnosis of 66.1–98.2% of cases. Analysis of lesion evolution over more than 5 years revealed modifications in 17% of hemangiomas, 23.9% of nonparasitic cysts, and 75% of cases of focal fatty infiltration. Systematic pretherapy liver sonography can be proposed owing to the high frequency of benign liver lesions that can create diagnostic problems during follow-up of cancer patients. Correspondence to: J. N. Bruneton     

Comparison of multislice CT arthrography and MR arthrography for the detection of articular cartilage lesions of the elbow

The objective of this study was to compare the value of multislice CT arthrography and MR arthrography in the assessment of cartilage lesions of the elbow joint. Twenty-six cadaveric elbow specimens were examined with the use of CT arthrography and MR arthrography prior to joint exploration and macroscopic inspection of articular cartilage. Findings at CT and MR arthrography were compared with macroscopic assessments in 104 cartilage areas. At macroscopic inspection, 45 cartilage lesions (six grade 2 lesions, 25 grade 3 lesions, 14 grade 4 lesions) and 59 areas of normal articular cartilage were observed. With macroscopic assessment as the gold standard CT and MR arthrography showed an overall sensitivity/specificity of 80/93% and 78/95% for the detection of cartilage lesions, respectively. Only two of six grade 2 lesions were detected by CT and MR arthrography. For the diagnosis of grade 3 and 4 lesions, the sensitivity/specificity was 87/94% with CT arthrography, and 85/95% with MR arthrography. In an experimental setting multislice CT arthrography and MR arthrography showed a similar performance in the detection of cartilage lesions. Both methods indicated limited value in the diagnosis of grade 2 articular cartilage lesions.     

Comparison of gadolinium-EOB-DTPA-enhanced and diffusion-weighted liver MRI for detection of small hepatic metastases

Objective

To compare the accuracy of gadolinium ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI with that of diffusion-weighted MRI (DWI) in the detection of small hepatic metastases (2 cm or smaller).

Methods

Forty-five patients underwent abdominal MRI at 3 T, including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), heavily T2WI (HASTE), DWI with a b-value of 500 s/mm² and contrast-enhanced MRI with Gd-EOB-DTPA. Two groups were assigned and compared: group A (T1WI, T2WI, HASTE and contrast-enhanced study with Gd-EOB-DTPA), and group B (T1WI, T2WI, HASTE and DWI). Two observers independently interpreted the images obtained in a random order. For all hepatic metastases, the diagnostic performance using each imaging set was evaluated by receiver-operating characteristic (ROC) curve analysis.

Results

A total of 51 hepatic metastases were confirmed. The area under the ROC curve (Az) of group A was larger than that of group B, and the difference in the mean Az values between the two image sets was statistically significant, whereas, there were three metastases that lay near thin vessels or among multiple cysts and were better visualised in group B than in group A.

Conclusion

Gd-EOB-DTPA-enhanced MRI showed higher accuracy in the detection of small metastases than DWI.     

比较Gd-EOB-DTPA增强MRI与扩散加权成像对肝内小转移灶的检出

目的比较Gd-EOB-DTPA增强MRI与扩散加权成像(DWI)检出肝内小转移灶(2cm或更小)的准确性。方法 45例病人行腹部3TMRI检查,所用序列包括T1加权     

MRI与CT 检测肝脏占位病变临床价值分析

目的：比较MRI和增强CT扫描在肝脏占位病变诊断中的应用价值。方法采用MRI和增强CT扫描对肝脏占位病变患者进行检查,探讨两组方法在肝脏占位病变诊断中的作用。结果本组10例肝细胞癌中9例（90．00％）呈快进快出型强化方式（图1B ）,11例肝脏转移瘤中9例（81．82％）呈边缘环形强化,10例肝血管瘤中9例（90．00％）病灶呈渐进性强化,18例肝囊肿动态增强病变均未见强化。M RI与临床病理确诊结果符合率（91．53％）明显高于增强C T ,且差异具有统计学意义。结论 CT、MR联合应用有助于提高肝脏占位性病变诊断水平的提高。