Background In 2006, we reported results of a randomized trial of laparoscopic paraesophageal hernia repair (LPEHR), comparing primary diaphragm repair (PR) with primary repair buttressed with a ...biologic prosthesis (small intestinal submucosa SIS). The primary endpoint, radiologic hiatal hernia (HH) recurrence, was higher with PR (24%) than with SIS buttressed repair (9%) after 6 months. The second phase of this trial was designed to determine the long-term durability of biologic mesh-buttressed repair. Methods We systematically searched for the 108 patients in phase I of this study to assess current clinical symptoms, quality of life (QOL) and determine ongoing durability of the repair by obtaining a follow-up upper gastrointestinal series (UGI) read by 2 radiologists blinded to treatment received. HH recurrence was defined as the greatest measured vertical height of stomach being at least 2 cm above the diaphragm. Results At median follow-up of 58 months (range 42 to 78 mo), 10 patients had died, 26 patients were not found, 72 completed clinical follow-up (PR, n = 39; SIS, n = 33), and 60 repeated a UGI (PR, n = 34; SIS, n = 26). There were 20 patients (59%) with recurrent HH in the PR group and 14 patients (54%) with recurrent HH in the SIS group (p = 0.7). There was no statistically significant difference in relevant symptoms or QOL between patients undergoing PR and SIS buttressed repair. There were no strictures, erosions, dysphagia, or other complications related to the use of SIS mesh. Conclusions LPEHR results in long and durable relief of symptoms and improvement in QOL with PR or SIS. There does not appear to be a higher rate of complications or side effects with biologic mesh, but its benefit in reducing HH recurrence diminishes at long-term follow-up (more than 5 years postoperatively) or earlier.
Because many patients with aortic pathology also have compromised renal function, we wished to investigate dual-energy computed tomography (DECT) aortography with 50% reduced iodine dose compared to ...single-energy computed tomography (SECT) aortography with standard iodine dose.
Fifty patients had DECT aortography with 50% reduced iodine dose. Thirty-four of these patients had prior SECT aortography with standard iodine dose. DECT images were reconstructed at both 50 and 77 keV and were compared to SECT 120 kVp images. Reviewers measured aortic attenuation, image noise, and scored vascular enhancement. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated. Volume CT dose index was recorded.
Mean iodine dose was 47 g for SECT and 24 g for DECT. Aortic attenuation was highest at reduced iodine dose DECT 50 keV (570 ± 105 Hounsfield units HU) compared to 77 keV (239 ± 40 HU) or to standard iodine dose SECT 120 kVp (356 ± 69 HU) (P < 0.05). Image noise was greatest at 50 keV compared to 77 keV and 120 kVp (P < 0.05) but was similar between 77 keV and 120 kVp (P > 0.05). SNR and CNR were the same at 50 keV and 120 kVp (P > 0.05). Mean vascular enhancement scores were all above 3.0 (good, typical enhancement). Volume CT dose index was 11.7 mGy for DECT and 11.8 mGy for SECT (P = 0.37).
DECT aortography with 50% reduced iodine reconstructed at 50 keV resulted in significantly greater aortic attenuation, good subjective vascular enhancement, and comparable SNR and CNR compared to standard iodine dose SECT. DECT image noise at 77 keV was similar to SECT at 120 kVp.
The objective of this study was to develop and demonstrate a technique to eliminate venous enhancement in contrast-enhanced magnetic resonance lymphangiography through shortening T2⁎ in the blood ...pool, thus allowing for a lymphatic-only map. Administration of the blood-pool iron agent ferumoxtyol in addition to intracutaneous gadolinium during contrast-enhanced magnetic resonance lymphangiography allows for suppression of vascular structures to achieve venous-free lymphatic mapping.
The right ventricular (RV) volume is commonly measured from magnetic resonance images using Simpson's method from the stack of short-axis images acquired for analysis of the left ventricle. We ...compared the RV volume measured using Simpson's method to the RV volume measured using 3-dimensional reconstruction and the piecewise smooth subdivision surface (PSSS) method. We studied 6 normal subjects and 18 patients whose right ventricles carried a systemic pressure load, 1/2 with dexto-transposition of the great arteries repaired with an atrial baffle and 1/2 with levo-transposition of the great arteries. The right ventricle was reconstructed from manually traced borders from the short- and long-axis views using the PSSS method. Simpson's analysis was performed on short-axis views alone. The RV volumes were smaller when analyzed using Simpson's method than using the PSSS method. The underestimation averaged 12 ± 19 ml (7 ± 12% of PSSS volume; p <0.001), without a significant difference between the groups. The ejection fraction was similar using both methods in patients with transposition of the great arteries and was overestimated in normal subjects. Image review revealed that the volume underestimation using Simpson's method was more frequently due to difficulty in interpreting the basal short-axis images than the apical images. In conclusion, to obtain accurate analysis of the short-axis views for RV volume measurement, it would be helpful to incorporate information from additional images, such as the long-axis views, to assist in delineating this chamber's complex anatomy.
To compare diagnostic accuracy of contrast-enhanced computed tomographic angiography (CTA) and gadolinium-enhanced magnetic resonance angiography (MRA) for the assessment of hemodynamically ...significant transplant renal artery stenosis (TRAS). After institutional review board approval, records of 27 patients with TRAS confirmed on digital subtraction angiography (DSA) were retrospectively reviewed. A total of 13 patients had MRA and 14 had CTA before DSA. Two board-certified fellowship-trained radiologists, one each from interventional radiology and body imaging blindly reviewed the DSA and CTA or MRA data, respectively. Sensitivity (SN), specificity (SP), positive predictive value, and negative predictive value of MRA and CTA were estimated using 50% stenosis as the detection threshold for significant TRAS. These parameters were compared between modalities using the Fisher exact test. Bias between MRA or CTA imaging and DSA was tested using the Wilcoxon signed-rank test. Two patients were excluded from the MRA group owing to susceptibility artifacts obscuring the TRAS. The correlation between MRA and DSA measurements of stenosis was r = 0.57 (95% CI:−0.02, 0.87; P = 0.052) and between CTA and DSA measurements was r = 0.63 (95% CI: 0.14, 0.87; P = 0.015); the difference between the 2 techniques was not significant ( P = 0.7). Both imaging modalities tended to underestimate the degree of stenosis when compared with DSA. MRA group (SN and SP: 56% and 100%, respectively) and CTA group (SN and SP: 81% and 67%, respectively). There were no significant differences in detection performance between modalities ( P >0.3 for all measures). We did not find that either modality had any advantage over the other in terms of measuring or detecting significant stenosis. Accordingly, MRA may be preferred over CTA after positive color Doppler ultrasound screening when not contraindicated owing to lack of ionizing radiation or nephrotoxic iodinated contrast. However, susceptibility of artifacts owing to surgical clips at the anastomosis may limit diagnostic utility of MRA as found in 2 of 13 patients. Trend towards no significant difference between the CTA and enhanced MRA in the detection of hemodynamically significant TRAS.
The purpose of this study was to assess the use of semiquantitative contrast-enhanced parameter analysis as an objective criteria for improving the magnetic resonance (MR) evaluation of ...hepatocellular carcinoma (HCC) in patients with cirrhosis. Contrast-enhanced MR examination findings from 19 patients with 21 pathologically proven HCC were evaluated using a dedicated liver image postprocessing workstation. Contrast-enhancement kinetic curves were created for each lesion, and 4 enhancement parameters (arterial wash-in slope, arterial-portal slope, arterial-equilibrium slope, and portal-equilibrium slope) were defined from the signal intensity-time plots. The accuracy of each enhancement parameter for the characterization of HCC was assessed. Statistical analysis revealed that an arterial-phase wash-in slope percentage value >1.35 per sec had a sensitivity of 86%, a specificity of 71%, and an accuracy of 79% for the correct characterization of HCC, whereas an arterial-equilibrium wash-out slope percentage value<0.05 per sec had a sensitivity of 86%, a specificity of 81%, and an accuracy of 83%. Although there were significant differences among all groups, the greatest accuracy for differentiation based on receiver operating curve analysis appears to be with arterial and arterial-equilibrium phases. Semiquantitative analysis of lesion contrast kinetics could provide objective parameters to improve the characterization of HCC on contrast-enhanced MR images.
Reply Oelschlager, Brant K., MD, FACS; Pellegrini, Carlos A., MD, FACS; Mitsumori, Lee M., MD ...
Journal of the American College of Surgeons,
2012, Letnik:
215, Številka:
1
Journal Article
PDF