Tissue Iron Distribution in Anemic Patients with End-Stage Kidney Disease: Results of a Pilot Study.

Background/Objectives: Anemia is a frequent multifactorial co-morbidity in end-stage kidney disease (ESKD) associated with morbidity and poor QoL. Apart from insufficient erythropoietin formation, iron deficiency (ID) contributes to anemia development. Identifying patients in need of iron supplementation with current ID definitions is difficult since no good biomarker is available to detect actual iron needs. Therefore, new diagnostic tools to guide therapy are needed. Methods: We performed a prospective cohort study analyzing tissue iron content with MRI-based R2*-relaxometry in 20 anemic ESKD patients and linked it with iron biomarkers in comparison to 20 otherwise healthy individuals. Results: ESKD patients had significantly higher liver (90.1 s-1 vs. 36.1 s-1, p < 0.001) and spleen R2* values (119.8 s-1 vs. 19.3 s-1, p < 0.001) compared to otherwise healthy individuals, while their pancreas and heart R2* values did not significantly differ. Out of the 20 ESKD patients, 17 had elevated spleen and 12 had elevated liver R2* values. KDIGO guidelines (focusing on serum iron parameters) would recommend iron supplementation in seven patients with elevated spleen and four patients with elevated liver R2* values. Conclusions: These findings highlight that liver and especially spleen iron concentrations are significantly higher in ESKD patients compared to controls. Tissue iron overload diverged from classical iron parameters suggesting need of iron supplementation. Measurement of MRI-guided tissue iron distribution might help guide treatment of anemic ESKD patients.

Tissue iron distribution in patients with anemia of inflammation: Results of a pilot study.

Anemia of inflammation (AI) is frequently present in subjects with inflammatory disorders, primarily caused by inflammation-driven iron retention in macrophages. So far, only limited data on qualitative and quantitative estimates of tissue iron retention in AI patients exist. We performed a prospective cohort study analyzing splenic, hepatic, pancreatic, and cardiac iron content with MRI-based R2*-relaxometry in AI patients, including subjects with concomitant true iron deficiency (AI+IDA) hospitalized between 05/2020-01/2022. Control groups were individuals without inflammation. Spleen R2* values in AI patients with ferritin ≤200 µg/L (AI+IDA) were comparable with those found in controls. In AI patients with ferritin >200 µg/L, spleen (47.6 s-1 vs. 19.3 s-1 , p < .001) and pancreatic R2* values (32.5 s-1 vs. 24.9 s-1 , p = .011) were significantly higher compared with controls, while liver and heart R2*-values did not differ. Higher spleen R2* values were associated with higher ferritin, hepcidin, CRP, and IL-6 concentrations. Spleen R2* values normalized in AI patients after recovery (23.6 s-1 vs. 47.6 s-1 , p = .008), while no changes were found in patients with baseline AI+IDA. This is the first study investigating tissue iron distribution in patients with inflammatory anemia and AI with concomitant true iron deficiency. The results support the findings in animal models demonstrating iron retention in macrophages, which are primarily accumulating in the spleen under inflammatory conditions. MRI-related iron measurement may help to better characterize actual iron needs and to define better biomarker thresholds in the diagnosis of true ID in patients with AI. It may qualify as a useful diagnostic method to estimate the need for iron supplementation and to guide therapy.

Ultrasound-guided versus computed tomography-controlled periradicular injections of the first sacral nerve: a prospective randomized clinical trial.

AIM: To compare ultrasound (US)-guided versus computed tomography (CT)-controlled periradicular injections of the first sacral spinal (S1) nerve in a prospective randomized clinical trial. MATERIALS AND METHODS: Thirty-nine patients with S1-radiculopathy were consecutively enrolled for 40 periradicular injections and assigned to an US or CT guided group. Needle position after US-assisted placement was controlled by a low-dose CT-scan. Accessibility, accuracy, and intervention time were compared. The overall effect on pain was matched evaluating the visual analog scale (VAS) decrease before and one month after the intervention. RESULTS: The mean intervention time was lower in the US-group compared to the CT-group: 4.4±3.46 min (1.3-13.2) vs. 6.5±3.03 min (2.4-12.5). Using CT-controlled infiltration the mean number of needle passes was with 1.15 higher than utilizing US-guidance. The therapeutic effect (mean difference between pre- and post-intervention, VAS scores) for the CT-group was 4.85±2.52 and for the US-group 4.55±2.74 with no significant difference between the two groups (p=0.7). CONCLUSION: US-controlled infiltrations of the first sacral nerve show a similar therapeutic effect to the time consuming, and ionizing CT-controlled injections and result in a significant reduction of procedure expenditure and avoidance of radiation.

1.5-T MR relaxometry in quantifying splenic and pancreatic iron: retrospective comparison of a commercial 3D-Dixon sequence and an established 2D multi-gradient echo sequence.

OBJECTIVES: To compare the quantitative measurement of splenic and pancreatic iron content using a commercial 3D-Dixon sequence (qDixon) versus an established fat-saturated R2* relaxometry method (ME-GRE). METHODS: We analyzed splenic and pancreatic iron levels in 143 MR examinations (1.5 T) using the qDixon and a ME-GRE sequence (108 patients: 65 males, 43 females, mean age 61.31 years). Splenic and pancreatic R2* values were compared between both methods using Bland-Altman plots, concordance correlation coefficients (CCC), and linear regression analyses. Iron overload (R2* > 50 1/s) was defined for both organs and compared using contingency tables, overall agreement, and Gwet's AC1 coefficient. RESULTS: Of all analyzable examinations, the median splenic R2* using the qDixon sequence was 25.75 1/s (range: 5.6-433) and for the ME-GRE sequence 35.35 1/s (range: 10.9-400.8) respectively. Concerning the pancreas, a median R2* of 29.93 1/s (range: 14-111.45) for the qDixon and 31.25 1/s (range: 14-97) for the ME-GRE sequence was found. Bland-Altman analysis showed a mean R2* difference of 2.12 1/s with a CCC of 0.934 for the spleen and of 0.29 1/s with a CCC of 0.714 for the pancreas. Linear regression for the spleen/pancreas resulted in a correlation coefficient of 0.94 (p < 0.001)/0.725 (p < 0.001). Concerning iron overload, the proportion of overall agreement between the two methods was 91.43% for the spleen and 93.18% for the pancreas. CONCLUSIONS: Our data show good concordance between R2* values obtained with a commercial qDixon sequence and a validated ME-GRE relaxometry method. The 3D-qDixon sequence, originally intended for liver assessment, seems to be a reliable tool for non-invasive evaluation of iron content also in the spleen and the pancreas. KEY POINTS: • A 3D chemical shift imaging sequence and 2D multi-gradient echo sequence show good conformity quantifying splenic and pancreatic R2* values. • The 3D chemical shift imaging sequence allows a reliable analysis also of splenic and pancreatic iron status. • In addition to the liver, the analysis of the spleen and pancreas is often helpful for further differential diagnostic clarification and patient guidance regarding the iron status.

MRI of middle ear cholesteatoma: The importance of observer reliance from diffusion sequences.

BACKGROUND AND PURPOSE: Diffusion-weighted imaging(DWI) in MRI has been developed as an important tool for the detection of cholesteatoma. Various DWI sequences are available. This study aims to evaluate the importance of the observer's reliance level for the detection of cholesteatoma. METHODS: Forty patients meeting the following criteria were included in the study: (1) chronic otitis media, (2) preoperative MRI including various DWI sequences, and (3) middle-ear surgery. The MRI protocol contained the following sequences: (1) axial and (2) coronal echoplanar imaging (EPI) readout-segmented (RESOLVE) DWI with Trace acquisition and (3) coronal non-EPI half-Fourier acquired single-shot turbo spin-echo (HASTE) DWI. Cholesteatoma diagnosis was based on standard diagnostic criteria for cholesteatoma with DWI. Additionally, the radiologists were asked to grade personal reliance on their diagnosis using a Likert-type scale from 1 = very insecure to 5 = very secure. RESULTS: Axial and coronal RESOLVE DWI showed a sensitivity of 77.3% and a specificity of 72.2%, respectively. The mean reliance was 3.9 for axial and 3.8 for coronal images. HASTE DWI had a sensitivity/specificity of 81.8%/66.7% with the highest reliance of all evaluated sequences (4.4). Cases with a reliance level of 5 showed a sensitivity/specificity of 100% in all sequences. A reliance level of 5 was given in the axial and coronal RESOLVE DWI in 32.5% of cases and in the HASTE DWI in 57.5%. CONCLUSION: The evaluated DWI sequences showed comparable results. The reliance level significantly improved the predictor of cholesteatoma disease with MRI techniques.

MR elastography in patients with suspected diffuse liver disease at 1.5T: Intraindividual comparison of gradient-recalled echo versus spin-echo echo-planar imaging sequences and investigation of potential confounding factors.

PURPOSE: To compare liver stiffness (LS) in patients with suspected diffuse liver disease between gradient-recalled-echo magnetic resonance elastography (GRE-MRE) and different spin-echo echo-planar imaging (SE-EPI-MRE) sequences and to investigate confounding factors including fat, iron, age, and sex. METHOD: LS was measured at 1.5T using GRE-MRE, SE-EPI-MRE and short-TE-SE-EPI-MRE (hiSE-EPI-MRE) sequences and compared using Bland-Altman-plots together with concordance correlation coefficients (CCC). Success gradings were evaluated considering possible confounding factors. RESULTS: 305 patients (225 male, 80 females, mean age 51.12 years) were included. 109/305 showed hepatic iron overload, 183 hepatic steatosis. The mean difference (bias) in stiffness values between GRE-MRE and SE-EPI-MRE/hiSE-EPI-MRE was 0.15/0.2 kPa (LOA: -0.72,0.41 kPa/-0.94,0.55 kPa), between SE-EPI-MRE and hiSE-EPI-MRE 0.04 kPa (LOA: -0.62,0.53 kPa). The CCC for agreement between stiffness values for GRE-MRE and SE-EPI-MRE was 0.94 (0.92-0.95), 0.89 (0.86-0.91) for hiSE-EPI-MRE and GRE-MRE and 0.94 (0.92-0.95) for SE-EPI-MRE and hiSE-EPI-MRE. Using GRE-MRE, 72/305 showed unusable results whereby all these patients had high iron levels (mean R2*=209.7 1/s). For SE-EPI-MRE and hiSE-EPI-MRE only 10/305 and 8/305 were inconclusive respectively, corresponding to a significantly higher iron load (mean R2*= 549.2 1/s for SE-EPI-MRE and 570.7 1/s for hiSE-EPI-MRE). Concerning fat, age or sex no significant influence on success was observed for all sequences. CONCLUSIONS: Good agreement of LS values was observed between GRE-MRE and SE-EPI-MRE sequences. The number of successful exams, however, was considerably lower for GRE-MRE, mainly due to iron content. Study reference number: AN5093.

MRI-Based Iron Phenotyping and Patient Selection for Next-Generation Sequencing of Non-Homeostatic Iron Regulator Hemochromatosis Genes.

BACKGROUND AND AIMS: High serum ferritin is frequent among patients with chronic liver disease and commonly associated with hepatic iron overload. Genetic causes of high liver iron include homozygosity for the p.Cys282Tyr variant in homeostatic iron regulator (HFE) and rare variants in non-HFE genes. The aims of the present study were to describe the landscape and frequency of mutations in hemochromatosis genes and determine whether patient selection by noninvasive hepatic iron quantification using MRI improves the diagnostic yield of next-generation sequencing (NGS) in patients with hyperferritinemia. APPROACH AND RESULTS: A cohort of 410 unselected liver clinic patients with high serum ferritin (defined as ≥200 µg/L for women and ≥300 µg/L for men) was investigated by HFE genotyping and abdominal MRI R2*. Forty-one (10%) patients were homozygous for the p.Cys282Tyr variant in HFE. Of the remaining 369 patients, 256 (69%) had high transferrin saturation (TSAT; ≥45%) and 199 (53%) had confirmed hepatic iron overload (liver R2* ≥70 s-1 ). NGS of hemochromatosis genes was carried out in 180 patients with hepatic iron overload, and likely pathogenic variants were identified in 68 of 180 (38%) patients, mainly in HFE (79%), ceruloplasmin (25%), and transferrin receptor 2 (19%). Low spleen iron (R2* <50 s-1 ), but not TSAT, was significantly associated with the presence of mutations. In 167 patients (93%), no monogenic cause of hepatic iron overload could be identified. CONCLUSIONS: In patients without homozygosity for p.Cys282Tyr, coincident pathogenic variants in HFE and non-HFE genes could explain hyperferritinemia with hepatic iron overload in a subset of patients. Unlike HFE hemochromatosis, this type of polygenic hepatic iron overload presents with variable TSAT. High ferritin in blood is an indicator of the iron storage disease, hemochromatosis. A simple genetic test establishes this diagnosis in the majority of patients affected. MRI of the abdomen can guide further genetic testing.

Rare median nerve anatomy - possible cause for carpal tunnel syndrome?

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Performance of different Dixon-based methods for MR liver iron assessment in comparison to a biopsy-validated R2* relaxometry method.

OBJECTIVES: To prospectively evaluate a 3D-multiecho-Dixon sequence with inline calculation of proton density fat fraction (PDFF) and R2* (qDixon), and an improved version of it (qDixon-WIP), for the MR-quantification of hepatic iron in a clinical setting. METHODS: Patients with increased serum ferritin underwent 1.5-T MRI of the liver for the evaluation of hepatic iron overload. The imaging protocol for R2* quantification included as follows: (1) a validated, 2D multigradient-echo sequence (initial TE 0.99 ms, R2*-ME-GRE), (2) a 3D-multiecho-Dixon sequence with inline calculation of PDFF and R2* (initial TE 2.38 ms, R2*-qDixon), and optionally (3) a prototype (works-in-progress, WIP) version of the latter (initial TE 1.04 ms, R2*-qDixon-WIP) with improved water/fat separation and noise-corrected parameter fitting. For all sequences, three manually co-registered regions of interest (ROIs) were placed in the liver. R2* values were compared and linear regression analysis and Bland-Altman plots calculated. RESULTS: Forty-six out of 415 patients showed fat-water (F/W) swap with qDixon and were excluded. A total of 369 patients (mean age 52 years) were included; in 203/369, the optional qDixon-WIP was acquired, which showed no F/W swaps. A strong correlation was found between R2*-ME-GRE and R2*-qDixon (r2 = 0.92, p < 0.001) with Bland-Altman revealing a mean difference of - 3.82 1/s (SD = 21.26 1/s). Correlation between R2*-GRE-ME and R2*-qDixon-WIP was r2 = 0.95 (p < 0.001) with Bland-Altman showing a mean difference of - 0.125 1/s (SD = 30.667 1/s). CONCLUSIONS: The 3D-multiecho-Dixon sequence is a reliable tool to quantify hepatic iron. Results are comparable with established relaxometry methods. Improvements to the original implementation eliminate occasional F/W swaps and limitations regarding maximum R2* values. KEY POINTS: • The 3D-multiecho-Dixon sequence for 1.5 T is a reliable tool to quantify hepatic iron. • Results of the 3D-multiecho-Dixon sequence are comparable with established relaxometry methods. • An improved version of the 3D-multiecho-Dixon sequence eliminates minor drawbacks.

Magnetic resonance cholangiopancreatography with compressed sensing at 1.5 T: clinical application for the evaluation of branch duct IPMN of the pancreas.

OBJECTIVES: To evaluate magnetic resonance cholangiopancreatography (MRCP) with compressed sensing (CS) for the assessment of branch duct intraductal papillary mucinous neoplasm (BD-IPMN) of the pancreas. For this purpose, conventional navigator-triggered (NT) sampling perfection with application-optimized contrast using different flip angle evolutions (SPACE) MRCP was compared with various CS-SPACE-MRCP sequences in a clinical setting. METHODS: A total of 41 patients (14 male, 27 female, mean age 68 years) underwent 1.5-T MRCP for the evaluation of BD-IPMN. The MRCP protocol consisted of the following sequences: conventional NT-SPACE-MRCP, CS-SPACE-MRCP with long (BHL, 17 s) and short single breath-hold (BHS, 8 s), and NT-CS-SPACE-MRCP. Two board-certified radiologists evaluated image quality, duct sharpness, duct visualization, lesion conspicuity, confidence, and communication with the main pancreatic duct in consensus using a 5-point scale (1-5), with higher scores indicating better quality/delineation/confidence. Maximum intensity projection reconstructions and originally acquired data were used for evaluation. Wilcoxon signed-rank test was used to compare the intra-individual difference between sequences. RESULTS: BHS-CS-SPACE-MRCP had the highest scores for image quality (3.85 ± 0.79), duct sharpness (3.81 ± 1.05), and duct visualization (3.81 ± 1.01). There was a significant difference compared with NT-CS-SPACE-MRCP (p < 0.05) but no significant difference to the standard NT-SPACE-MRCP (p > 0.05). Concerning diagnostic quality, BHS-CS-SPACE-MRCP had the highest scores in lesion conspicuity (3.95 ± 0.92), confidence (4.12 ± 1.08), and communication (3.8 ± 1.06), significantly higher compared with NT-SPACE-MRCP, BHL-SPACE-MRCP, and NT-CS-SPACE-MRCP (p = <0.05). CONCLUSIONS: MRCP with CS 3D SPACE for the evaluation of BD-IPMN at 1.5 T provides the best results using a short breath-hold sequence. This approach is feasible and an excellent alternative to standard NT 3D MRCP sequences. KEY POINTS: • 1.5-T MRCP with compressed sensing for the evaluation of branch duct IPMN is a feasible method. • Short breath-hold sequences provide the best results for this purpose.

[Magnetic resonance elastography of the liver : Worth knowing for clinical routine]. / Magnetresonanzelastographie der Leber : Wissenswertes zur klinischen Routine.

BACKGROUND: Magnetic resonance elastography (MRE) is a noninvasive, quantitative, MRI-based method to evaluate liver stiffness. Beside biopsy and ultrasound elastography, this imaging method plays in many places a significant role in the detection and additive characterization of chronic liver disease. OBJECTIVES, MATERIALS AND METHODS: Based on the literature, a brief review of the underlying method and the commercially available products is given. Furthermore, the practical procedure, the analysis, and the interpretation of clinically relevant questions are illustrated and a comparison with ultrasound elastography is provided. RESULTS: This relative "young" MRI method allows extensive evaluation of mechanical properties of the liver and is an important diagnostic tool especially in follow-up examinations. The MRE of the liver is with a maximum technical failure rate of 5.8% a robust technique with high accuracy and an excellent re-test reliability as well as intra- and interobserver reproducibility. There is a high diagnostic certainty within the framework of most important clinical indications, the quantification of fibrosis, and with a very good correlation with the "gold standard" biopsy. CONCLUSION: Based on its rising clinical relevance and the broad usage, MRE of the liver is increasingly used in many centers and in routine liver protocols. Therefore, basic knowledge of this method is essential for every radiologist.

Immediate Surgery in Acute Type A Dissection and Neurologic Dysfunction: Fighting the Inevitable?

BACKGROUND: Neurologic dysfunction remains an ongoing challenge in the diagnosis of type A aortic dissection (AAD). Our study analyzed the impact of preoperative neurologic dysfunction (PND) on outcome and assessed a potential link between PND and specific patterns of postoperative neurologic injury. METHODS: Medical records of 338 patients (70.1% men; mean age, 59.3 ± 13.7 years) undergoing surgical repair for AAD were screened for the presence of PND. Preoperative characteristics, surgical treatment, and hospital and neurologic outcomes were analyzed according to patients with PND (PND+) and without PND (PND-) RESULTS: There were 50 patients (14.8%) admitted with PND. PND+ patients showed significantly higher rates of postoperative neurologic injury (44.4%) than PND- patients (14.3%; P < .001) with a specific pattern of ischemic lesions in accordance with preoperative neurologic status. While PND+ patients suffered mainly from right hemispheric strokes (66.7% vs 32.4% in PND- patients, P = .024), PND- patients more frequently presented with bilateral cerebral ischemia (56.8% vs 13.3% in PND+ patients, P = .004). Multivariable analysis identified presence of PND (odds ratio, 2.977; 95% confidence interval, 1.357-6.545) as an independent predictor for new postoperative neurologic injury. PND was associated with impaired survival (P = .005). CONCLUSIONS: This study identified an association of preoperative neurologic status and specific stroke patterns after surgical repair of AAD. Irrespective of timing of surgery and reperfusion strategies, preoperative neurologic dysfunction is strongly associated with impaired neurologic outcome.

Derotational femoral osteotomy changes patella tilt, patella engagement and tibial tuberosity trochlear groove distance.

PURPOSE: The aim was to assess the influence of femoral derotational osteotomy on patella tilt (PT), axial patella engagement (AEI) and tibial tuberosity trochlear groove distance (TTTG). METHODS: Derotational femoral osteotomy was performed on ten lower limbs of body donors embalmed with alcohol-glycerine. Femoral torsion, tibial torsion, knee torsion, PT, AEI and TTTG were evaluated on axial CT slices for an absolute femoral torsion of 15°, 20°, 25°, 30°, 35° and 40°. A linear mixed model analysis was used to estimate the effect of femoral torsion on PT, AEI, TTTG and knee torsion adjusted for correlation due to repeated observations. Estimates with 95% confidence intervals were used to represent the mean change in the dependent variables for one unit of change (degree, mm or AEI) in the predictor variable. RESULTS: A significant correlation was observed between femoral torsion and AEI (p < 0.001), PT (p < 0.001) and TTTG distance (p = 0.002). In cases of increased internal femoral torsion, a significant decreased AEI (estimate - 0.003, 95% CI - 0.003 to - 0.002), an increased PT (estimate 0.3, 95% CI 0.2-0.4) and an increased TTTG distance (estimate 0.1, 95% CI 0.1-0.2) were observed. No correlation was seen between change in femoral torsion and knee torsion (n.s.). CONCLUSIONS: Derotational femoral osteotomy has a significant impact on patella tilt and axial patella engagement. Moreover, TTTG distance is slightly changed by a derotational femoral osteotomy, which has to be taken into account preoperatively when considering surgical procedures. LEVEL OF EVIDENCE: Level V.

A simple approach for ultrasound-guided pararadicular injections in the sacral spine: a pilot computer tomography controlled cadaver study.

AIMS: Injection therapies play an increasingly decisive role in the treatment of lower back pain. Cumulative studies could show the benefits of ultrasound-guided instillation procedures in the cervical and lumbar spine. We conducted this study to provide a new simple sonographic approach for pararadicular injections of the sacral spinal nerves and to prove the feasibility and accuracy by means of CT and anatomic dissection. MATERIAL AND METHODS: Eight ultrasound-guided injections at four different levels of the sacral spine on a human ethanol-glycerol-embalmed cadaver (S1-S4) were performed. By means of sonography the sacral foramina were identified and the spinal needles were advanced in "in-plane technique" to the medial margin of the respective sacral foramen. Subsequently a solution of blue dye and contrast agent were injected. Then CT scans and anatomic dissection of the cadaver were performed to verify the correct placement of the needle tips and to visualize the dispersion of the injected solution in the respective compartment. RESULTS: Altogether a 100% success rate for a correct injection could be achieved. CT examination confirmed the correct placement of every needle tip within the intended compartment. Also, the anatomic dissections affirmed the appropriate needle positioning. Moreover, the blue dye dispersion was seen in the correct compartments and around the targeted spinal nerves. CONCLUSIONS: Although this study was only performed on cadaveric models, this new sonographic approach for pararadicular injections in the sacral spine allows an easy, precise and unerring needle placement within the dorsal sacral foramen.

Monitoring Iron Overload: Relationship between R2* Relaxometry of the Liver and Serum Ferritin under Different Therapies.

OBJECTIVE: The objective of this study was to evaluate the relationship between hepatic magnetic resonance imaging (MRI) with R2* relaxometry and serum ferritin in therapy monitoring of patients with iron overload. Further, a possible influence of the chosen therapy (phlebotomy or chelation) was assessed. MATERIALS AND METHODS: We retrospectively evaluated 42 patients with baseline and follow-up R2* relaxometry and determination of serum ferritin before and during therapeutic phlebotomy or iron chelation therapy or watchful waiting, respectively. Linear regression analysis was used to analyze the correlation between changes of R2* and serum ferritin. Regression lines for different groups were compared with analysis of covariance. RESULTS: We found a moderate positive statistical correlation (r = 0.509) between serum ferritin and R2*, a moderate positive correlation between absolute R2* changes and serum ferritin changes (r = 0.497), and a strong correlation for percentage changes (r = 0.712). The correlation analysis between relative changes of R2* and serum ferritin for the different therapies resulted in a strong correlation between phlebotomy and chelation (r = 0.855/0.727) and a moderate for no applied therapy (r = 0.536). In 22/92 paired examinations, a discordance of R2* and ferritin was found, particularly involving patients under chelation. CONCLUSIONS: Despite the good correlation between serum ferritin and R2* relaxometry in monitoring iron overload, treatment response may be misinterpreted when only serum ferritin is considered. Although ferritin is an acceptable and far cheaper tool for monitoring, MRI should be performed for confirmation, especially in case of unexpected ferritin changes, particularly under chelation therapy.

Stroke after emergent surgery for acute type A aortic dissection: predictors, outcome and neurological recovery.

OBJECTIVES: Despite improvement in operative and cerebral perfusion techniques, cerebral malperfusion and neurological injury remain a dreaded complication of acute type A aortic dissection. We aimed to identify predictors for postoperative stroke and analyse the impact on morbidity, neurological recovery and mid-term survival. METHODS: Between 2000 and 2017, 303 (71.9% men, mean age 58.9 ± 13.6 years) patients with acute type A aortic dissection underwent surgical repair. Clinical and imaging data were retrospectively evaluated. Patients were divided into 2 groups depending on the presence of postoperative stroke. RESULTS: Postoperative stroke was detected in 15.8% (n = 48) of the patients. Patients with postoperative stroke showed higher rates of preoperative cardiopulmonary resuscitation (stroke: 18.8% vs no stroke: 3.5%, P < 0.001) and malperfusion syndrome (stroke: 47.9% vs no stroke: 22.4%, P < 0.001). Multivariable analysis identified the presence of bovine aortic arch [odds ratio (OR) 2.33, 95% confidence interval (CI) 1.086-4.998; P = 0.030], preoperative cardiopulmonary resuscitation (OR 6.483, 95% CI 1.522-27.616; P = 0.011) and preoperative malperfusion (OR 2.536, 95% CI 1.238-5.194; P = 0.011) as independent predictors for postoperative stroke. Postoperative stroke had a strong impact on morbidity and was associated with higher rates of postoperative complications and a significantly longer hospital stay (stroke: 23 ± 16 days vs no stroke: 17 ± 18 days, P = 0.021). Postoperative stroke was not independently associated with in-hospital mortality (adjusted OR 1.382, 95% CI 0.518-3.687; P = 0.518). There was no difference in mid-term survival between patients with stroke and patients without stroke. CONCLUSIONS: This study identified independent preoperative predictors for postoperative stroke. Although postoperative stroke was associated with significant morbidity and postoperative complications, significant impairment in mid-term survival could not be confirmed by the data.

CAIPIRINHA-Dixon-TWIST (CDT)-VIBE MR imaging of the liver at 3.0T with gadoxetate disodium: a solution for transient arterial-phase respiratory motion-related artifacts?

PURPOSE: To determine whether CAIPIRINHA-Dixon-TWIST (CDT) volume-interpolated breath-hold examination (VIBE) improves image quality by reducing gadoxetate-disodium-associated transient arterial-phase motion artefacts in magnetic resonance imaging (MRI) of the liver. MATERIALS AND METHODS: MRI studies of the liver from 270 patients who had received gadoxetate disodium were retrospectively evaluated in regard to arterial timing accuracy and arterial phase motion artefact severity (VIBE: 90/270, CAIPIRINHA-VIBE: 90/270 and CDT-VIBE: 90/270 cases). Three independent and blinded readers assessed arterial phase timing and motion artefact severity (5-point scale). Interrater agreement was calculated by weighted kappa. Continuous variables were compared via a two-sided ANOVA, categorical variables via a χ2 test. An ordinal regression analysis was performed to identify other predictors of motion artefacts. RESULTS: CDT-VIBE improved correct late arterial timing rates and reduced motion-related image deterioration rates. Successful late arterial liver visualisation was achieved in 56.7% (VIBE) compared with 66.7% (CAIPIRINHA-VIBE) and 84.4% (CDT-VIBE) (P < 0.0001). Good/excellent image quality was achieved in 56.7% vs. 66.7% and 73.3%, respectively (P = 0.03). Male sex negatively influenced image quality (P = 0.03). CONCLUSION: CDT-VIBE increases the diagnostic utility of gadoxetate disodium-based liver MRI by reducing respiratory motion artefacts and optimising late arterial visualisation compared with VIBE and CAIPIRINHA-VIBE. KEY POINTS: • CAIPIRINHA-Dixon-TWIST-VIBE-MRI (CDT) mitigates effects of acute transient dyspnoea caused by gadoxetate disodium. • CDT improves late arterial imaging compared with VIBE and CAIPIRINHA-VIBE. • The rate of ideal late arterial images is higher with CDT-VIBE vs. VIBE or CAIPI-VIBE. • The impact of respiratory motion artefacts on arterial phase images can be reduced.

In DeBakey Type I Aortic Dissection, Bovine Aortic Arch Is Associated With Arch Tears and Stroke.

BACKGROUND: The study sought to evaluate if a bovine aortic arch (BAA) influences the location of the entry site in acute aortic dissection type A (AADA) and to identify the impact of BAA on postoperative outcome, especially stroke. METHODS: A total of 315 patients underwent surgery due to AADA DeBakey type I (72.1% men, mean age 59.5 ± 13.4 years) between 2002 and 2015. Imaging studies and operative reports were screened for presence of BAA and location of the entry site. Patients were divided into 2 groups based on presence (BAA+) and absence (BAA-) of BAA (BAA+ n = 49, BAA- n = 264). Dissection patterns, surgical treatment, risk factors for postoperative complications, and long-term outcome were analyzed. RESULTS: Prevalence of BAA in patients with AADA was 15.6%. Location of the entry site was more commonly in the aortic arch in patients with BAA (BAA+ 46.8% versus BAA- 14.3%; p < 0.001). Multivariable analysis identified BAA (odds ratio [OR], 5.9; 95% confidence interval [CI], 2.89 to 12.04; p < 0.001) and preoperative competent aortic valve (OR, 2.26; 95% CI, 1.19 to 4.31; p = 0.013) as independent predictors for an arch tear. Thirty-nine patients (12.4%) suffered from stroke. Patients with BAA had higher stroke rates (BAA+ 24.5% versus BAA- 10.2%; p = 0.009). BAA emerged as one risk factor for stroke in the setting of AADA (OR, 2.69; 95% CI, 1.2 to 6.0; p = 0.016). Long-term survival was comparable for patients with BAA and patients without congenital arch anomalies. CONCLUSIONS: BAA is an independent predictor for the distinctive location of the entry site in the aortic arch and risk factor for stroke.