Claus Koelblinger

Lymph node ratio after curative surgery for intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (ICC) is rare but its incidence is rising worldwide. The value of lymph node dissection for ICC is under discussion; the current staging systems do not differentiate between numbers of involved nodes.

Gadoxetic acid-enhanced 3.0 T MR imaging versus multidetector-row CT in the detection of colorectal metastases in fatty liver using intraoperative ultrasound and histopathology as a standard of reference.

OBJECTIVE To compare the diagnostic value of gadoxetic acid-enhanced MRI at 3.0 T with 64-row MDCT in the detection of colorectal liver metastases in diffuse fatty infiltration of the liver after neoadjuvant chemotherapy. METHODS Twenty-three patients with colorectal liver metastases and at moderate to severe steatosis (25-90%) underwent prospectively preoperative tri-phasic MDCT (Somatom Sensation 64, Siemens) and gadoxetic acid-enhanced MRI (3-T Magnetom Trio, Siemens). All patients underwent surgical resection of liver metastases. Intraoperative ultrasound (IOUS) was carried out, which served as the standard of reference, together with histopathology. RESULTS Overall, 68 metastases (range, 0.4-6 cm; 31/68 metastases [46%] ≤ 1 cm) were found at histology. MDCT detected 49/68 lesions (72%), and MRI 66/68 (97%, p < 0.001). For lesions ≤ 1 cm, MDCT detected only 13/31 (41.9%) and MRI 29/31 (93%, p < 0.001). Eight false-positive lesions were detected by MDCT, seven small lesions by MRI. There was no statistically significant difference between the two modalities in the detection of lesions > 1 cm (p = 0.250). IOUS detected all metastases and revealed two false-positive diagnoses. CONCLUSION Gadoxetic acid-enhanced 3.0 T MRI is superior to 64-row MDCT in detecting colorectal liver metastases ≤ 1 cm during preoperative staging in patients with liver steatosis. A combination of MRI and IOUS may further improve the outcome of surgical treatment.

Gadobenate Dimeglumine–enhanced 3.0-T MR Imaging versus Multiphasic 64–Detector Row CT: Prospective Evaluation in Patients Suspected of Having Pancreatic Cancer

PURPOSE To compare the diagnostic performance (detection, local staging) of multiphasic 64-detector row computed tomography (CT) with that of gadobenate dimeglumine-enhanced 3.0-T magnetic resonance (MR) imaging in patients suspected of having pancreatic cancer. MATERIALS AND METHODS The institutional review board approved this prospective study, and all patients provided written informed consent. Multidetector CT and MR imaging were performed in 89 patients (48 women aged 46-89 years [mean, 65.6 years] and 41 men aged 46-86 years [mean, 65.3 years]) suspected of having pancreatic cancer on the basis of findings from clinical examination or previous imaging studies. Two readers independently assessed the images to characterize lesions and determine the presence of focal masses, vascular invasion, distant metastases, and resectability. Findings from surgery, biopsy, endosonography, or follow-up imaging were used as the standard of reference. Logistic regression, the McNemar test, and κ values were used for statistical analysis. RESULTS Focal pancreatic masses were present in 63 patients; 43 patients had adenocarcinoma. For reader 1, the sensitivities and specificities in the detection of pancreatic adenocarcinoma were 98% (42 of 43 patients) and 96% (44 of 46 patients), respectively, for CT and 98% (42 of 43 patients) and 96% (44 of 46 patients) for MR imaging. For reader 2, the sensitivities and specificities were 93% (40 of 43 patients) and 96% (44 of 46 patients), respectively, for CT and 95% (41 of 43 patients) and 96% (44 of 46 patients) for MR imaging. Vessel infiltration was determined in 22 patients who underwent surgery, and reader 1 obtained sensitivities and specificities of 90% (nine of 10 vessels) and 98% (119 of 122 vessels), respectively, for CT and 80% (eight of 10 vessels) and 96% (117 of 122 vessels) for MR imaging; for reader 2, those values were 70% (seven of 10 vessels) and 98% (120 of 122 vessels) for CT and 50% (five of 10 vessels) and 98% (120 of 122 vessels) for MR imaging. Both readers correctly assessed resectability in 87% (13 of 15 patients) of cases with CT and 93% (14 of 15 patients) of cases with MR imaging. Nonresectability was assessed correctly with CT in 75% (six of eight patients) of cases by reader 1 and 63% (five of eight patients) of cases by reader 2; nonresectability was correctly assessed with MR imaging in 75% (six of eight patients) of cases by reader 1 and 50% (four of eight patients) of cases by reader 2. None of the differences between modalities and readers were statistically significant (P > .05). CONCLUSION Both CT and MR imaging are equally suited for detecting and staging pancreatic cancer. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101189/-/DC1.

State-of-the-art magnetic resonance imaging of pancreatic cancer.

Technical advances of magnetic resonance imaging (MRI), including ultrahigh-field magnetic resonance at 3.0 T, parallel imaging techniques, and multichannel receive coils of the abdomen, have promoted MRI of the pancreas. For adenocarcinoma, which is the most common malignant pancreatic tumor, helical CT has been most often used for detection and staging, but it has limitations in the detection of small cancers 2 cm in diameter or less (sensitivity, 63%). Moreover, it is not very accurate in determining nonresectability, because small liver metastases, peritoneal carcinomatosis, and subtle signs of vascular infiltration may be missed. At ultrahigh field at 3.0 T, gadolinium-enhanced MRI using volume-interpolated 3-dimensional gradient-recalled echo pulse sequences with near-isotropic voxels are very useful for detection of subtle abnormalities. Mangafodipir-enhanced MRI reveals a very high tumor-pancreas contrast, which helps to diagnose small cancers. Contrast-enhanced MRI is a problem-solving tool in case of equivocal CT: it helps to differentiate between cancer and focal pancreatitis. Neuroendocrine carcinoma may present with a spectrum of appearances at MRI, but the primary tumor and liver metastases are hypervascular in approximately 70%. In this article, pancreas imaging protocols for 1.5 and 3.0 T are explained. We present the imaging features of pancreatic cancer and the important questions in staging, which should be addressed by the radiologist.

Magnetic resonance imaging spectrum of medulloblastoma.

IntroductionTwo medulloblastoma variants were recently added to the WHO classification of CNS tumours. We retrospectively analysed the imaging findings of 37 classic and 27 cases of variant medulloblastomas to identify imaging characteristics that might suggest a particular MB subtype.MethodsSixty-four patients from three institutions were included. Location, tumour margins, signal intensities on conventional MRI, enhancement pattern, the presence of haemorrhage, calcifications and hydrocephalus were recorded and analysed. Signal characteristics on diffusion-weighted MR images and MR spectra were evaluated when available.ResultsThirty-seven classic type of MB (CMB), twelve cases of desmoplastic/nodular medulloblastoma (DMB), nine medulloblastomas with extensive nodularity (MB-EN), five cases of anaplastic and one of large-cell medulloblastoma were included. Fifty of 64 tumours were located in the 4th ventricle region. On T2WI, CMB were all hyperintense, whereas DMB and MB-EN showed isointensity in up to 66%. One third of the classic MB showed only subtle marginal or linear enhancement. All medulloblastoma variants showed marked enhancement.ConclusionThe results of our study suggest: (a) an age-dependent distribution of MB variants, with DMB and MB-EN more common in younger children; (b) a female predominance in DMB; (c) a more common off-midline location in DMB (50%) and MB-EN (33%) variants.

Segmental and lobar administration of drug-eluting beads delivering irinotecan leads to tumour destruction: a case-control series.

BACKGROUND Irinotecan-loaded drug-eluting beads represent a novel drug delivery method that allows for the locoregional delivery of irinotecan to colorectal liver metastases (CRLM). The method has shown impressive response rates. However, the pathological response to this treatment has not previously been demonstrated. METHODS Patients with easily resectable CRLM were treated with drug-eluting beads delivering irinotecan (DEBIRI) 4 weeks prior to resection. Pathological tumour response was graded using a validated system. The intraoperative detection of previously unidentified disease allowed for the assessment of pathological responses directly attributable to bead treatment. RESULTS In Patient 1, segmental embolization of the target lesion in segment VIII resulted in 100% necrosis (0% viability). An untreated lesion in segment IV was found to be 30% viable. In Patient 2, subsegmental embolization of the target lesion in segment VI resulted in 60% necrosis and 40% fibrosis (0% viability). An untreated lesion in segment VI remained 60% viable. In Patient 3, lobar embolization of the target lesion in segment II resulted in 0% viability. Two further lesions within the treated hemiliver, both with 0% viability, and one lesion in the untreated hemiliver with 45% viability were discovered at laparotomy. CONCLUSIONS This series demonstrates the effectiveness of DEBIRI in the treatment of CRLM. High rates of tumour destruction are possible, even with the proximal lobar administration of DEBIRI. Lobar administration appears to be an appropriate method of delivery for integration into future therapeutic regimens.

Fetal magnetic resonance imaging of lymphangiomas.

Abstract Objectives: To evaluate the fetal magnetic resonance imaging findings of lymphangiomas. Methods: The magnetic resonance scans of eight fetuses with lymphangiomas were evaluated. Magnetic resonance evaluation included: number; size; signal intensities of the lesions; thickness of the septae; configuration of the margins; presence of blood breakdown products; change in size or signal intensity (in four patients with multiple examinations); exact expansion of the lesions to the adjacent anatomical structures; and concomitant pathological findings. Results were compared with postpartum clinical assessment and imaging in seven patients and with autopsy in one patient. Results: Two retroperitoneal, three thoracic, and three cervical lymphangiomas (diameters between 3.3 and 15.6 cm) were included. All lesions consisted of macrocysts, and additional microcystic parts were found in three lymphangiomas. Blood breakdown products were found in one lesion. Agreement with postpartum imaging was excellent. One patient received intrauterine drainage for chylothorax, and one pregnancy was terminated. Conclusions: Fetal lymphangiomas display the same magnetic resonance imaging features as postnatal lymphangiomas. Intrauterine magnetic resonance characterization of lymphangiomas provides the exact delineation, detection of associated and/or concomitant pathologies, and differential diagnosis among other cystic pathologies. Patient management may be altered with respect to the type and/or time of treatment, and with regard to the continuation or termination of pregnancy.

Sinonasal imaging after Caldwell–Luc surgery: MDCT findings of an abandoned procedure in times of functional endoscopic sinus surgery

BACKGROUND AND PURPOSE Today, functional endoscopic sinus surgery (FESS) is performed in most of the patients with sinonasal inflammatory disease. The postoperative imaging findings of FESS in multidetector computed tomography (MDCT) considerably differ from those of historic Caldwell-Luc (CL) maxillary sinus surgery which is an uncommon procedure today. Thus, the postoperative CL imaging findings may lead to diagnostic confusion and misinterpretation. Therefore, this study explicitly presents the MDCT findings of post-CL patients which have not been described previously. METHODS Twenty-eight patients with clinically suspected sinusitis and documented history of CL-procedure underwent 16 row MDCT (MDCT Mx8000 IDT Philips) with multiplanar reconstructions of the paranasal sinuses in the axial plane. The following parameters were used: 140kV, 50mAs; 16mmx0.75mm detector collimation; 1mm reconstructed slice thickness; 0.5mm increment. The studies were reconstructed with a bone algorithm (W3000/L600; 1mm slice thickness) in axial plane and coronal plane (3mm slice thickness). The images were retrospectively evaluated for the presence of normal surgery-related and pathological findings. RESULTS Surgery-related imaging characteristics presented as follows: an anterior and a medial bony wall defect and sclerosis and sinus wall thickening were observed in all 28/28 cases (100%). Collaps of the sinus cavity was seen in 26/28 cases (92.9%). Furthermore, inflammatory disease of the operated sinus(es) was found in 23/28 cases (82.1%): 14/28 patients (50%) had inflammatory mucosal thickening of the operated sinus(es) as well as of other sinonasal cavities and 9/28 patients (32.1%) had inflammatory mucosal thickening limited to the operated sinus(es). A postoperative mucocele was depicted in 3/28 cases (10.7%). 2/28 patients (7.1%) showed neither maxillary nor other mucosal swelling. CONCLUSION MDCT with multiplanar reconstructions is a precise method to evaluate post-CL patients and helps to differentiate normal surgery-related findings, which may mimic pathology, from real pathological findings.

Hepatic steatosis assessment with 1H-spectroscopy and chemical shift imaging at 3.0 T before hepatic surgery: Reliable enough for making clinical decisions?

PURPOSE To compare the accuracy of liver fat quantification using chemical shift imaging (CSI) and H1 MR-spectroscopy (MRS) at 3.0 T in patients undergoing liver resection. METHODS Totally 35 patients were included in this prospective IRB approved study. The histopathologically assessed liver fat was compared to the hepatic fat fractions calculated with CSI (with and without spleen correction) and MRS. Spearmans rank correlation and Fisher z-test were used for correlation analysis. Sensitivity and specificity regarding the detection of marked steatosis were calculated for the different modalities and compared using the McNemar test. RESULTS MRS (r=.85) and CSI with spleen correction (r=.85) showed a significantly better correlation (p=.03) with histology compared to CSI without spleen correction (r=.67). Sensitivity and specificity for the detection of marked steatosis was 100% (12/12) and 87% (20/23) for MRS and 92% (11/12) and 83% (19/23) for CSI with spleen correction (p>.12). CONCLUSION For the assessment of hepatic steatosis both CSI with spleen correction and MRS at 3.0 T, show a good correlation with histology. CSI without spleen correction should not be used. Sensitivity and specificity for the detection of marked steatosis are high with both modalities. However, results that are scattered around the cut-off values are not reliable enough for clinical decisions.

Quantification of the subcutaneous fat layer with MRI in fetuses of healthy mothers with no underlying metabolic disease vs. fetuses of diabetic and obese mothers.

Abstract Objective: To assess the age-dependent fetal subcutaneous fat layer (SCFL) of non-diabetic, normal-weight mothers and fetuses of mothers with gestational diabetes (GDM) and normal body weight or obesity. Methods: In a prospective study, we evaluated 115 MRI examinations of fetuses with no history of (maternal) metabolic disease [gestational week (GW) 29 to 39/40] and 50 examinations of mothers with GDM and normal body weight or obesity. The SCFL was measured at predetermined anatomical landmarks. Measurements were correlated with the maternal body mass index (BMI) and glycated hemoglobin A1c (HbA1c)-values in diabetic mothers. Results: In fetuses of non-diabetic, normal-weight mothers, measurements showed high consistency within the respective GW and ranged from 2 mm at GW 29 at all measured points, up to 4.5 mm at the trunk and 6.0 mm at the extremities at GW 39/40. In 47/50 fetuses of mothers with GDM, the SCFL was within the range of fetuses of mothers with no metabolic disease. In three patients with GDM and BMI<30, the SCFL-thickness was decreased. No fetuses showed an increased SCFL-thickness. Conclusion: The SCFL of normally developed fetuses is easily detectable from GW 29 on T1-weighted images (T1-W), and increases with gestational age. The presented data provide physiological benchmarks to evaluate developmental status and may help in the prenatal diagnosis of abnormal growth and macrosomia. In pregnant women with well-controlled GDM, an increase of the SCFL is not expected.