Background: Free flap transplantation is used more and more frequently in order to cover extensive wound defects. The basic prerequisite for successful flap salvage after flap failure is a short time interval from failure until revision. For this rea
BACKGROUND: To estimate the presence and severity of capsular contracture in patients after breast implants an objective measurement tool is necessary. PATIENTS AND METHODS: Eleven patients (range of age 37 to 53 years) who underwent cosmetic breast
To evaluate the possibilities of flow detection using high resolution flow (HR Flow) and Glazing Flow technique in patients with liver parenchymal changes and flow changes in comparison to color-coded Doppler sonography (CCDS).All examinations were performed using a multi frequency matrix convex probe with high resolution technique (SC6-1U/Resona7, Mindray, Shenzhen, China) by one experienced examiner to evaluate the venous, portal venous and arterial liver flow with digital documentation of the dynamic flow parameters like peak systolic flow, end-diastolic flow and resistance index. For liver parenchymal stiffness changes shear wave elastography was performed with at least 10 measurements. By two independent readers an elevation was performed to evaluate the image quality and the degree of flow artefacts, from 0 = not available to 5 points with excellent image quality without flow artefacts.All 40 patients (24 men, 16 women, age 27-83 years, mean 56±5 years) showed morphology changes from B-Mode of the liver parenchyma to inhomogeneous tissue with higher stiffness evaluated by the shear wave elastography (1.45 m/s up to 2.79 m/s±1.79 m/s, considering F1 up to F4 fibrosis) and in 15 cases histopathologically proven liver cirrhosis. In 9 cases after non-acute thrombosis flow reduction of the portal vein was the reason for the diameter less than 5 mm. Flow parameters for the venous flow were between 8 cm/s up to 29 cm/s, mean 14±4 cm/s, for the hepatic portal vein 5 cm/s up to 57 cm/s, mean 17±5 cm/s, for the hepatic artery systolic flow between 50 cm/s up to 127±33 cm/s, end-diastolic flow from 22 cm/s up to 47±8 cm/s. Resistance index for the hepatic artery was between 0.41 up to 0.73, mean 0.67±0.25. The image quality for CCDS over all cases was evaluated for CCDS between 1 up to 4. The mean quality was 2.5±0.5, for HR Flow in combination with Glazing Flow 3±0.5, with significant differences for the 2 readers (P < 0.01).Combination of HR Flow with Glazing Flow could be helpful to evaluate morphological und hemodynamic changes of liver arterial flow, portal venous and venous flow. Reduction of flow artefacts in combination with a higher image quality could be helpful for optimizing the digital measurements also for follow up examinations.
AIM: This study aims to evaluate optimized breast implant surface-structure analysis by comparing high-end ultrasound technology with a new high frequency technique. This comparative study used new breast implants with different surfaces in an in vitro setting. METHODS: Nine idle silicon or polyurethane (PU) breast implants were examined by two investigators in an experimental in vitro study using two high-end ultrasound devices with multi-frequency transducers (6–15 MHz, 9–16 MHz, 12.5–33 MHz). The ultrasound B-Mode was optimized using tissue harmonic imaging (THI), speckle reduction imaging (SRI, level 0–5), cross beam (high, medium, low) and photopic. Using a standardized ultrasound protocol, the implants were examined in the middle (point of highest projection) and lateral, by two independent examiners. Image evaluation was performed on anonymized digital images in the PACS. The aim was to achieve an artifact-free recording of the surface structure, the surface coating, the total image structures and, as far as possible, an artifact-free internal representation of the implants. For independent surface evaluation a score was used (0 = undetectability of surface structures, rich in artifacts, 5 = best possible, artifact free image quality). RESULTS: The quality of ultrasound imaging of breast implant surfaces after the optimization of B-Scan differed significantly comparing high-end ultrasound technology with modern high-frequency ultrasound technology (p < 0,05). The following setting has been found to be the best setting with the highest image quality: B-Mode, SRI value 3, Crossbeam high level with color coded imaging for B- mode. In the total examined frequency range of 6–33 MHz, the highest image quality was found in the average frequency range of 12.5–33 MHz at both measured points. For both devices, device 1 (high-end) and device 2 (high frequency) ultrasound, the image quality was in the 12.5–33 MHz frequency range with an average image quality of 3.236. It was significantly higher, than in the lower frequency ranges and the same frequency range with THI. (p < 0,05). The image quality of the high-end sonography device was superior to the conventional high-frequency ultrasound device in all frequency ranges. CONCLUSION: High-end ultrasound imaging technology was superior in the quality of implant surface evaluation in comparison to high-frequency ultrasound sonography. The gained knowledge can serve as a basis for further multicenter clinical application and studies with the aim to develop an objective, precise tool to evaluate the implant and the surrounding tissue with ultrasound.
Corrected by: Comparison between Preoperative Quantitative Assessment of Bowel Wall Vascularization by Contrast-Enhanced Ultrasound and Operative Macroscopic Findings and Results of Histopathological Scoring in Crohn's DiseaseUltraschall Med 2011; 32(02): E1-E1DOI: 10.1055/s-0031-1299323
Is Contrast Harmonic Imaging (CHI) comparable to computed tomography angiography (CTA) scan in detecting and characterizing suspected endoleaks after endovascular abdominal aneurysm repair in a non-selected group including reintervention procedure and branched endografts in daily practice?In a prospective study computed tomography angiography (CTA) and contrast-enhanced ultrasound (CEUS) were performed in 30 consecutive patients (26 males, 4 females, mean age: 72 years, range: 38-87) with suspected endoleaks in follow-up (mean 13 months, range: 1-95) after endovascular abdominal aneurysm repair or procedure in dissection or penetrated ulcer of the aorta (25 infrarenal, 5 suprarenal stent grafts, mean aortic diameter 56 mm, range: 27-98). CTA was supposed to be gold standard for determining the presence of endoleaks (multislice CT, collimation 16 x 0.75 mm, 100 ml of iodized contrast agent bolus). Ultrasonography used a multi-frequency probe (1-4 MHz) with the modalities of colour coded Doppler sonography (CCDS), power Doppler (PD) combined with contrast enhancement and the technique of contrast harmonic imaging (CHI) and low mechanical index (MI < 0.2). 2.4 ml of SonoVue (Bracco, Altana Pharma GmbH, Italy) were administered to each patient intravenously as a bolus injection.Out of 30 patients, 21 endoleaks were identified in CTA (6 type I or III, 15 type II), 22 in CHI. Thus, sensitivity for CHI was therefore 99%, its specificity 85% (Spearman correlation coefficient (CC) 0.92). In follow-up the localizations of endoleak type I or III exclusively detected by CHI were confirmed as true positive by angiography. Due to its dynamic characteristic CHI seemed to be more helpful in characterization of endoleaks than CTA. In case of a rupture after reintervention a type III endoleak leads to prompt intervention before receiving the result of the CT scan. Altogether, CHI failed to identify 1 combined type I and II endoleak (sensitivity 0.99). Both, CCDS and PD were positive only in 6/30 patients (CC 0.33 and 0.39). Interestingly the application of contrast agent doubles the detection rate of endoleaks (12/30) in CCDS and PD (CC 0.39).Contrast harmonic imaging (CHI) compared to computed tomography angiography (CTA) accurately depicts endoleaks after endovascular abdominal aneurysm repair and stent-graft procedure in dissected and ulcerated aorta. It seems to be superior in characterization of the type of endoleaks and can be established in order to reduce iodized contrast agent and radiation exposure in follow-up. In contrast to CTA scan CHI can be offered to patients with chronic renal insufficiency and allows a dynamic examination and a perfusion analysis.
Purpose: The objective was to characterize the microcirculation of parathyroid adenomas using contrast-enhanced ultrasound (CEUS) and to evaluate if it can be used for diagnosis and localization of pathologic glands. Patients and methods: Thirty pati
To evaluate the additive clinical value of endoluminal contrast enhanced ultrasound (CEUS) after interventional placement of drainages in abdominal fluid collections.Examination of 30 patients using a 1-6 MHz convex probe (Resona 7, Mindray) to locate the fluid collection in B-Mode. Additionally, dynamic endoluminal CEUS with 1 ml sulphur-hexafluoride microbubbles was performed to measure the extent of the percutaneously drained abscesses. Independent assessment of dynamically stored images in PACS in DICOM format. Correlation to reference imaging using computed tomography (CT).A total of 30 patients were examined (17 m, 19-78 years, mean 56.1 years). Drainages were positioned in the liver in 15 cases, in the pelvis after kidney transplantation in 4 cases, close to the spleen in 1 case, and in the abdomen in 10 cases. In all cases abscesses showed marginal hyperaemia with reactive septations in CEUS. The drainage position was assessed by means of B-mode in all cases first and then by CEUS. In 4 cases CEUS showed a fistula to the pleura, in 5 cases to the peritoneum, in 2 cases to the intestine, in 5 cases to the biliary tract, corresponding to the CT. In 2 cases there was a hint of an anastomotic leakage after intestinal anastomosis, which was reliably detected by CT. The drainage was removed in 11 cases within a period of 2 to 5 days after CEUS control, in 9 cases within a period of 5 to 10 days. Another operation was necessary in 3 cases. A new drainage was placed in 2 cases. The required amount of ultrasound contrast medium is 1 ml endoluminally diluted to 9 ml sodium chloride.CEUS facilitates the exact localization and characterization of inflammatory abdominal fluid collections. Furthermore, possible fistulas can be detected that cannot be seen with conventional ultrasound.
This study was designed to determine if a) hyperbaric oxygen increases the tissue oxygenation of free flaps and b) verification of this effect is possible by using a recently validated and innovative method for two-dimensional pO₂ measurement (Luminescence lifetime imaging = LLI).Six patients with a free parascapular flap transplanted to the lower limb received hyperbaric oxygen (HBOT) therapy. The HBOT regimen consisted of treatment over 90 minutes with 100% O₂ (FiO₂ 1.0) at 240 kPa (Marx-Schema). The transcutaneous oxygen partial pressure (ptcO₂) was measured over the entire flap with the use of luminescence lifetime imaging (LLI) before and 30, 60, 120 minutes after treatment. The LLI is based on the oxygen dependent quenching of phosphorescence of the indicator dye platinum (II)-octaethyl-porphyrin implemented in a polystyrene sensor foil.In all six free flaps we could find a significant increase of tissue oxygen over the entire flap in form of increased R-values as well as subsequently calculated absolute ptcO₂ values over a period of 120 min after hyperbaric therapy. The ptcO₂ values increased significantly from 42.59 ± 1.11 Torr before to 81.14 ± 5.95 Torr after hyperbaric treatment (p < 0.001). Even after 2 hours the ptcO₂ values were significantly higher (83.45 ± 13.80 Torr) compared with values prior to HBOT (p < 0.006).The findings of this study demonstrated an increase of oxygen supply over the entire flap after hyperbaric oxygen therapy.