Is ultra low-dose CT with tin filtration useful for examination of SI joints? Can it replace X-ray in diagnostics of sacroiliitis?

OBJECTIVES: The first objective of our study was to determine the radiation exposure received by patients during tin-filtrated ultra-low-dose computed tomography (TFULDCT) of sacroiliac joints and to compare those to conventional X-ray doses. For comparison, we added a cohort examined by low-dose CT (LDCT) without tin filtration. The second objective was to compare the results of TFULDCT and X-ray in the detection of sacroiliitis. METHODS: Our retrospective study covered 45 patients, who were examined for suspected axial spondyloarthritis (AxSpA). The first group underwent TFULDCT as well as conventional radiography (CR); the second group underwent LDCT only without tin filtration. Effective doses of TFULDCT, LDCT and CR were calculated by an experienced medical physicist. TFULDCT and CR were independently evaluated by three investigators, who decided on the presence or absence of rheumatoid inflammatory bone changes. The results were statistically evaluated. RESULTS: In our cohort, the median effective dose for TFULDCT was 0.11 mSv, range (0.06-0.40 mSv), for LDCT 0.5 mSv (0.29-0.89 mSv), and for CR 0.25 mSv (0.06-1.87 mSv). We proved that TFULDCT produces a significantly lower percentage of uncertain results (23.3%; 95% CI: 11.3-41.6%) than CR (66.7%; 95% CI: 48.3-81.1%). CONCLUSIONS: Tin filtration helps to reduce CT radiation exposure to values lower than those resulting from CR. TFULDCT offers better overall diagnostic performance than CR. Our results prove that TFULDCT can replace CR in the diagnosis of sacroiliitis in the radiographical stage of AxSpA.

Influence of Mesenchymal Stem Cell Administration on The Outcome of Partial Liver Resection in a Porcine Model of Sinusoidal Obstruction Syndrome.

BACKGROUND: In patients with colorectal liver metastases, the possibility for radical liver resection can be limited by oxaliplatin-induced sinusoidal obstruction syndrome (SOS). This study investigates the potential of mesenchymal stem cells (MSC) to improve the outcome of liver resections in pigs with SOS. MATERIALS AND METHODS: SOS was induced in all animals (n=20) on day 0. Animals in the experimental group (n=8) received allogeneic MSC on day 7. Liver resection was performed in all animals on day 14 and the animals were observed until day 28. Ultrasound volumetry, biochemical analysis and histological examination of liver parenchyma was performed during the follow-up period. RESULTS: Six animals from the control group died prematurely, while all animals survived in the experimental group. According to histology, biochemical analysis and ultrasound volumetry, there were no significant differences between the groups documenting the effect of MSC. CONCLUSION: Single dose allogeneic MSC administration improved survival of animals with SOS undergoing partial liver resection. Further experiments with different timing of liver resection and MSC administration should be performed to investigate the effect of MSC in more detail.

Allogeneic Venous Grafts of Different Origin Used for Portal Vein Reconstruction After Pancreaticoduodenectomy - Experimental Study.

BACKGROUND: In clinical medicine, little is known about the use of allografts for portal vein (PV) reconstruction after pancreaticoduodenectomy (PD). Portal and caval systems are physiologically different, therefore the properties of allografts from caval and portal systems were studied here in a pig model. MATERIALS AND METHODS: PD with PV reconstruction with allogeneic venous graft from PV or inferior vena cava (IVC) was performed in 26 pigs. Biochemical analysis and ultrasonography measurements were performed during a 4-week monitoring period. Computer simulations were used to evaluate haemodynamics in reconstructed PV and explanted allografts were histologically examined. RESULTS: The native PV and IVC grafts varied in histological structure but were able to adapt morphologically after transplantation. Computer simulation suggested PV grafts to be more susceptible to thrombosis development. Thrombosis of reconstructed PV occurred in four out of five cases in PV group. CONCLUSION: This study supports the use of allografts from caval system for PV reconstruction in clinical medicine when needed.

Submucosal mucoid as a late complication after appendectomy-A case report.

INTRODUCTION: Shortly after an operation infection, intraabdominal abscess, seroma, haemorrhage or development of paralytic ileus may occur. Postoperative adhesions, nonspecific abdominal pain without signs of obstruction, incisional hernia and appendicitis or mucocele in appendiceal stump present common late complications. We present a unique case of a late complication after appendectomy. PRESENTATION OF CASE: The case report describes a unique expansion in the ascending colon of a young athlete with long-lasting abdominal pain in the lower right quadrant. Colonoscopy showed a lesion in a wall of the ascending colon. Computed tomography (CT) confirmed a cystoid formation of high content density in a wall of the caecum. A right hemicolectomy was performed. Histology showed a lesion located in the submucosa with intestinal lining and stroma rich in lymphoid cells. These are the typical attributes of the wall of the appendix. Other parts of the wall were not demonstrated, and there was no communication with the lumen of the native bowel. CONCLUSION: A submucosal cavity filled with acellular matter, which were probably disintegrated epithelioid structures, and calcifications were found in the ascending colon, while no intestinal cell atypia or dysplasia was found. The case cannot be classified under any previously presented diagnosis.

Cystic Appearance on Imaging Methods (Bosniak III-IV) in Histologically Confirmed Papillary Renal Cell Carcinoma is Mainly Characteristic of Papillary Renal Cell Carcinoma Type 1 and Might Predict a Relatively Indolent Behavior of Papillary Renal Cell Carcinoma.

AIM: The aim of this study was to determine the proportion of cystic tumors according to preoperative CT (Bosniak III, IV) among surgically treated patients with histologically confirmed papillary renal cell carcinoma (pRCC) and to assess progression rates among patients with and without cystic appearance on imaging. METHODS: A total of 138 patients with pRCC histology surgically treated in the period of January 2007-March 2017 were included. Clinical and radiological characteristics, type of surgery, histopathology results, and follow-up data were recorded and statistically evaluated. RESULTS: Forty-one cases (29.7%) of cystic lesions (10× BIIF, 14× BIII, 17× BIV) were detected by CT. Patients with pRCC1 significantly more frequently presented with cystic appearance on CT (33/78; 42.3%) in comparison to other papillary types (8/60; 13.3%; p = 0.0002). During a median follow-up time of 49.4 months, only 2 patients with cystic lesions progressed after surgery. CONCLUSIONS: Cystic appearance on imaging methods is mainly a characteristic of pRCC1 (42.3%). Cystic morphology on imaging might predict a relatively indolent behavior of all pRCC types. Preoperative scoring systems including tumor growth patterns (cystic vs. solid) are needed for further classification.

Monitoring after radiofrequency ablation of liver tumors: contrast-enhanced ultrasound (CEUS) vs. contrast-enhanced computer tomography (CECT), two days after procedure.

AIM: Our research evaluated the ability of contrast-enhanced ultrasound (CEUS) and contrast enhanced computer tomography (CECT), performed 48 h after radiofrequency ablation (RFA), to detect residual tumor tissue. As recently published studies have evaluated periprocedural CEUS performed within 24 h after procedure and their results were not satisfactory, it seems that postponing the control test by one day could increase the sensitivity of both methods. PATIENTS AND METHODS: We evaluated 33 patients with 37 lesions, who met the criteria for our study. The criteria were 1) the treated lesion is sonographically viewable and 2) the patient underwent both CEUS and CECT control 48 h after treatment and additional follow-up 3 months later by CECT. Presence of residual tumor tissue and the size of necrosis were recorded and compared to the results of 3-months CECT. RESULTS: Nine residues were present in our group. CEUS and CECT showed similar sensitivity (66.7% and 77.8%, respectively) and identical specificity (both 96.4%) for detection of residual tumor tissue. CEUS significantly underestimated the size of necrosis in comparison to CECT (on average by 2.4 mm, P=0.0005). Over the 3-months follow-up period the size of necrosis decreased in all patients (on average by 7.2 mm, P<0.0001). CONCLUSION: The quality of tumor residue detection in 48-h CEUS was comparable to that of 48-h CECT. This finding suggests the CEUS being a feasible substitute for CECT. Both methods show reasonable sensitivity; therefore this timing seems to be appropriate for the first post-treatment control while also allowing for early retreatment if residual tumor tissue is found.