Racial Disparities in Treatment and Outcomes of Patients With Hepatitis C Undergoing Elective Total Joint Arthroplasty.

BACKGROUND: African Americans have the highest prevalence of chronic Hepatitis C virus (HCV) infection. Racial disparities in outcome are observed after elective total hip arthroplasty (THA) and total knee arthroplasty (TKA). This study sought to identify if disparities in treatments and outcomes exist between Black and White patients who have HCV prior to elective THA and TKA. METHODS: Patient demographics, comorbidities, HCV characteristics, perioperative variables, in-hospital outcomes, and postoperative complications at 1-year follow-up were collected and compared between the 2 races. Patients who have preoperative positive viral load (PVL) and undetectable viral load were identified. Chi-square and Fisher's exact tests were used to compare categorical variables, while 2-tailed Student's Kruskal-Wallis t-tests were used for continuous variables. A P value of less than .05 was statistically significant. RESULTS: The liver function parameters, including aspartate aminotransferase and model for end-stage liver disease scores, were all higher preoperatively in Black patients undergoing THA (P = .01; P < .001) and TKA (P = .03; P = .003), respectively. Black patients were more likely to undergo THA (65.8% versus 35.6%; P = .002) and TKA (72.1% versus 37.3%; 0.009) without receiving prior treatment for HCV. Consequently, Black patients had higher rates of preoperative PVL compared to White patients in both THA (66% versus 38%, P = .006) and TKA (72% versus 37%, P < .001) groups. Black patients had a longer length of stay for both THA (3.7 versus 3.3; P = .008) and TKA (4.1 versus 3.0; P = .02). CONCLUSIONS: The HCV treatment prior to THA and TKA with undetectable viral load has been shown to be a key factor in mitigating postoperative complications, including joint infection. We noted that Black patients were more likely to undergo joint arthroplasty who did not receive treatment and with a PVL. While PVL rates decreased over time for both races, a significant gap persists for Black patients.

Femoral Head Osteonecrosis: Computed Tomography Not Needed to Identify Collapse When Using the Association Research Circulation Osseous Staging System.

Background: The 2019 Revised Association Research Circulation Osseous (ARCO) Staging Criteria for Osteonecrosis of the Femoral Head (ONFH) only requires plain radiographs and magnetic resonance imaging (MRI) to diagnose and stage ONFH; however, the effectiveness of the 2019 ARCO criteria in the absence of computed tomography (CT) scans has not been investigated. Therefore, the purpose of this study was to evaluate whether CT scanning is a necessary modality for diagnosing/staging ONFH using the ARCO staging system. More specifically, do CT scans help differentiate pre- and post-collapse lesions more than MRI scans? Methods: A study was conducted on 228 ONFH patients diagnosed between January 1, 2008, and December 31, 2018, at a single academic medical center. CT and MRI scans were reviewed by the senior author and other contributors. The ONFH classification was compared between the 2 scans to determine if CT scans were able to further differentiate staging of collapsed lesions vs MRI scans. Results: A diagnosis of ONFH was made by MRI first in 57% (129/228) while 21% (48/228) used MRI and CT simultaneously. Only 22% (51/228) of cases were diagnosed by CT scans first. There were no cases where collapse was found by a CT scan that were not diagnosed by standard x-rays and/or MRIs. Conclusions: CT scans are not a useful adjunct for diagnosing or treating ONFH and are not necessary if MRI is ordered when using the Revised ARCO Staging System for ONFH diagnosis.

Child-Pugh Class B or C Liver Disease Increases the Risk of Early Mortality in Patients With Hepatitis C Undergoing Elective Total Joint Arthroplasty Regardless of Treatment Status.

BACKGROUND: Patients with hepatitis C virus (HCV) undergoing primary elective total joint arthroplasty (TJA) are at increased risk of postoperative complications. Patients with chronic liver disease and cirrhosis, specifically Child-Pugh Class B and C, who are undergoing general surgery have high 2-year mortality risks, approaching 60% to 80%. However, the role of Child-Pugh and Model for End-Stage Liver Disease classifications of liver status in predicting survivorship among patients with HCV undergoing elective arthroplasty has not been elucidated. QUESTION/PURPOSE: What factors are independently associated with early mortality (< 2 years) in patients with HCV undergoing arthroplasty? METHODS: We performed a retrospective study at three tertiary academic medical centers and identified patients with HCV undergoing primary elective TJA between January 2005 and December 2019. Patients who underwent revision TJA and simultaneous primary TJA were excluded. A total of 226 patients were eligible for inclusion in the study. A further 25% (57) were excluded because they were lost to follow-up before the minimum study requirement of 2 years of follow-up or had incomplete datasets. After the inclusion and exclusion criteria were applied, the final cohort consisted of 75% (169 of 226) of the initial patient population eligible for analysis. The mean follow-up duration was 53 ± 29 months. We compared confounding variables for mortality between patients with early mortality (16 patients) and surviving patients (153 patients), including comorbidities, HCV and liver characteristics, HCV treatment, and postoperative medical and surgical complications. Patients with early postoperative mortality were more likely to have an associated advanced Child-Pugh classification and comorbidities including peripheral vascular disease, end-stage renal disease, heart failure, and chronic obstructive pulmonary disease. However, both groups had similar 90-day and 1-year medical complication risks including myocardial infarction, stroke, pulmonary embolism, and reoperations for periprosthetic joint infection and mechanical failure. A multivariable regression analysis was performed to identify independent factors associated with early mortality, incorporating all significant variables with p < 0.05 present in the univariate analysis. RESULTS: After accounting for significant variables in the univariate analysis such as peripheral vascular disease, end-stage renal disease, heart failure, chronic obstructive pulmonary disease, and liver fibrosis staging, Child-Pugh Class B or C classification was found to be the sole factor independently associated with increased odds of early (within 2 years) mortality in patients with HCV undergoing elective TJA (adjusted odds ratio 29 [95% confidence interval 5 to 174]; p < 0.001). The risk of early mortality in patients with Child-Pugh Class B or C was 64% (seven of 11) compared with 6% (nine of 158) in patients with Child-Pugh Class A (p < 0.001). CONCLUSION: Patients with HCV and a Child-Pugh Class B or C at the time of elective TJA had substantially increased odds of death, regardless of liver function, cirrhosis, age, Model for End-Stage Liver Disease level, HCV treatment, and viral load status. This is similar to the risk of early mortality observed in patients with chronic liver disease undergoing abdominal and cardiac surgery. Surgeons should avoid these major elective procedures in patients with Child-Pugh Class B or C whenever possible. For patients who feel their arthritic symptoms and pain are unbearable, surgeons need to be clear that the risk of death is considerably elevated. LEVEL OF EVIDENCE: Level III, therapeutic study.

Total Joint Arthroplasty Should Not Be Delayed in Hepatitis C Patients After Successful Treatment Achieving a Sustained Viral Load.

Background: Preoperative treatment recommendations and optimal time to perform total joint arthroplasty (TJA) in patients with hepatitis C virus after treatment completion for achieving best outcomes have not been elucidated. We aim to determine (1) if undetectable viral load (UVL) prior to TJA leads to decreased postoperative complication rates, specifically periprosthetic joint infection (PJI), and (2) if delaying TJA after treatment completion has benefit in decreasing PJI. Methods: A retrospective review of all hepatitis C virus patients undergoing TJA at 3 academic tertiary care centers was conducted. A total of 270 TJAs performed from 2005 to 2019 were included, 125 with positive viral load at the time of surgery. The duration from completion of treatment regimen to TJA was recorded for the UVL cohort. The primary study outcome was PJI at 1-year follow-up. Secondary outcomes included in-hospital complications, mechanical revision TJA rates, and optimal time to TJA upon completion of treatment. Results: Patients with positive viral load at the time of TJA had longer length of stay (3.9 vs 2.9 days, P < .0001) and a higher PJI rate at 1 year postoperatively (9% vs 2%, P = .02) than UVL patients. There was no difference of in-hospital complications or revision rates for mechanical etiologies. Delaying TJA after achieving a sustained virologic response did not impact PJI rates. Conclusions: Sustained UVL prior to TJA is critical to minimize PJI irrespective of the treatment regimen utilized. Surgery can be performed with lower complication rates any time after achieving sustained virologic response. Level of Evidence: Level III, prognostic retrospective cohort study.

Prevertebral Soft Tissue Thickness of the Cervical Spine in Children: An Insensitive but Specific Aid in the Diagnosis of Occult Trauma.

BACKGROUND: The purpose of this study was to investigate the sensitivity and specificity of current cervical prevertebral soft tissue swelling (PVST) values in a cohort of children with known cervical fractures or dislocations. METHODS: Forty two children (average age 11.9, range 1.4 to 17.0 y) with documented cervical spine injury and 61 children (average age 11.9, range 0.5 to 17.9 y) with cervical pain but no injury were reviewed (January 2004 to December 2015). PVST was measured on lateral cervical radiographs at C2, C3, and C6. Patients were stratified by age (0 to 2 y, 3 to 6 y, 7 to 10 y, 11 to 15 y, and 16 y and above). The Wilcoxon rank sum test was used to compare PVST measurements at each spine level across injury and noninjury cohorts. Sensitivity and specificity were estimated to assess the ability of abnormal reference values to detect when a true injury was present. In addition, positive predictive value and negative predictive value were also estimated. RESULTS: The majority of c-spine injuries (31/42; 76%) involved bony fracture and 57% (24/42) were treated with a collar or brace. Comparison of PVST measurement found no difference at C2 ( P =0.07), C3 ( P =0.07), or at C6 ( P =0.99) across injury and non-injury cohorts. Sensitivity was poor at single-level measures for C2 (26%), C3 (31%), and C6 (24%), while specificity was relatively high (92%, 87%, and 79%, respectively). When an increased value at either C2 or C3 indicated injury, sensitivity increased to 36%, and when an increased measurement at just one of the 3 measured levels indicated injury, the sensitivity increased to 48%, while the specificity decreased to 72%. While retropharyngeal measures were more likely to detect injury than retrotracheal, C6 alone was increased in 5 of the 20 injury patients. CONCLUSIONS: PVST measurements exhibit poor sensitivity but good specificity as indicators for the diagnosis of occult cervical trauma in children. Negative values do not exclude injury; positive values suggest further evaluation. LEVELS OF EVIDENCE: Level III.

Development and Evaluation of Resident-Championed Point-of-Care Ultrasound Curriculum for Internal Medicine Residents.

Introduction: Point-of-care ultrasound (POCUS) is a powerful clinical tool that has seen widespread adoption, including in Internal Medicine (IM), yet standardized curricula designed by trained faculty are scant. To address the demand for POCUS education at our institution, we created a resident-championed curriculum with support from skilled faculty across multiple specialties. Our objective was to teach postgraduate year (PGY)-3 IM residents the basics of POCUS for evaluation of the pulmonary, cardiac, and abdominal systems through resident-developed workshops. The goal of acquisition of these skills was for resident education and to inform decisions to pursue further patient testing. Methods: Three half-day workshops were created to teach residents how to obtain and interpret ultrasound images of the pulmonary, cardiac, and abdominal systems. Workshops were comprised of didactic teaching and practical ultrasound instruction with expert supervision of clinicians within and outside of IM. Residents were asked to complete a written survey before and after each workshop to assess confidence, knowledge, and likelihood of future POCUS use. Results: Across the three workshops (pulmonary, cardiac, and abdominal), 66 sets of pre- and post-workshop surveys (32 pulmonary, 25 cardiac, and 9 abdominal) were obtained and analyzed. Confidence in and knowledge regarding POCUS use increased significantly across all three workshops. Likelihood of future use increased in the cardiac workshop. Conclusions: We implemented a resident-championed POCUS curriculum that led to improved attitudes and increased knowledge of POCUS for PGY-3 IM residents.

Cellular Angiofibroma Presenting as a Subepithelial Rectal Mass.

A very rare case of cellular angiofibroma arising from the rectum in a 62-year-old man with a normal colonoscopy 2 years earlier is reported. To our knowledge, this is the first such case reported in the literature. The tumor was transanally excised with clear margins, and the patient had no postoperative complications. It is key to accurately differentiate this lesion from other subepithelial rectal tumors and more aggressive genital soft tissue tumors because clinical management varies. We performed a review of clinical records and pathology as well as an extensive literature review.

Management of Gustilo-Anderson Type II and IIIA Open Long Bone Fractures in Children: Which Wounds Require a Second Washout?

INTRODUCTION: Timing of wound closure in pediatric Gustilo-Anderson grade II and IIIA open long bone fracture remain controversial. Our aims are (1) to determine the proportion of patients with these fractures whose wounds can be treated with early primary wound closure (EPWC); (2) to compare the complication rates between EPWC and delayed wound closure (DWC); and (3) to determine factors associated with higher likelihood of undergoing DWC. PATIENTS AND METHODS: At a level-1 pediatric trauma center, 96 patients (younger than 18 y) who sustained Gustilo-Anderson grade II and IIIA open long bone fractures (humerus, radius, ulnar, femur, or tibia) within a 10-year period (2006-2016) were included for this study. Decision for EPWC versus DWC was at the discretion of the attending surgeon at time of initial surgery. Data collection was via retrospective review of charts and radiographs. Particular attention was paid to the incidence of return to operating room rate, nonunion, compartment syndrome, and infection. Median follow-up duration was 7.5 months (interquartile range: 3.6 to 25.3 mo). All patients were followed-up at least until bony union. RESULTS: Overall, 81% of patients (78/96) underwent EPWC. Of the grade II fractures, 86% underwent EPWC. Four patients (5%) in the EPWC group and 1 patient (6%) in the DWC group had at least 1 complication. When controlling for mechanism of injury, Gustilo-Anderson fracture type and age, there was no difference in rate of complications between the EPWC and the DWC groups. Grade IIIA fractures and being involved in a motor vehicle accident were factors associated with a higher likelihood of undergoing DWC. CONCLUSION: The majority of grade II and IIIA pediatric long bone fractures may be safely treatable with EPWC without additional washouts. Future prospective research is required to further define the subgroups that can benefit from DWC. LEVEL OF EVIDENCE: Level IV-therapeutic, case cohort study.

Management of Fasciotomy Incisions After Acute Compartment Syndrome: Is Delayed Primary Closure More Feasible in Children Compared With Adults?

BACKGROUND: Recent adult literature has demonstrated that in the setting of acute compartment syndrome (ACS), if fasciotomy wounds are not closed after the first debridement, they are unlikely to be closed via delayed primary closure (DPC). The purpose of this study was to report the success of DPC through serial debridement in children with fasciotomy wounds secondary to ACS and to determine whether length of hospital stay is negatively affected by adopting a DPC strategy. METHODS: We identified all patients treated with fasciotomy for ACS (aged 0 to18 y). Patient, injury, and treatment characteristics were summarized by fasciotomy treatment type. Patients were grouped as: primary closure, DPC, and flap or skin graft (F/SG). For patients who required additional debridements after initial fasciotomy, treatment success was defined as closure by DPC (without requiring F/SG). Multivariable logistic regression was used to determine factors associated with additional surgeries, complications, and treatment success. RESULTS: A total of 82 children underwent fasciotomies for ACS. Fifteen (18%) patients were treated with primary closure at the time of their initial fasciotomy and were excluded from the remainder of the analysis, 48 (59%) patients underwent DPC, and 19 (23%) patients were treated with F/SG. The majority of delayed fasciotomy wounds were successfully closed by DPC (48/67, 72%) and the rate of successful closure remained consistent with each successive operative debridement. There were no differences across DPC and F/SG groups with respect to age, method of injury, or injury severity. Patients who underwent F/SG remained in the hospital for an average of 12 days compared with 8 days for those who underwent DPC (P<0.001). CONCLUSIONS: In the setting of ACS, pediatric fasciotomy wounds that are not closed after the first postfasciotomy debridement still have a high likelihood of being closed through DPC with serial surgical debridement. In children, persisting with DPC strategy for fasciotomy closure after ACS is more successful than it is in adults. LEVEL OF EVIDENCE: Level III.

Does Extended PET Acquisition in PET/MRI Rectal Cancer Staging Improve Results?

OBJECTIVE: The purpose of this study was to determine if extended PET acquisition times in the pelvis during PET/MRI increase detection rates of potentially metastatic lymph nodes in patients with rectal cancer. MATERIALS AND METHODS: Our study was approved by the institutional review board of the University of California, San Francisco. Twenty-two patients with biopsy-proven rectal cancer underwent imaging via simultaneous 3-T time-of-flight PET/MRI, with seven undergoing two separate PET/MRI examinations, for a total of 29 studies. Each examination included both a whole-body PET/MRI and a dedicated pelvic PET/MRI with both 3- and 15-minute PET acquisitions for the pelvis. Three radiologists interpreted each examination with PET only, MRI only, then combined PET and MRI examinations, using all available images. Additionally, the 3- and 15-minute PET acquisitions of the pelvis were reviewed separately by a single radiologist. RESULTS: A total of 94 lymph nodes were identified as abnormal on PET, all with MRI anatomic correlates. Of these, 37 (39.4%) were seen only on the dedicated 15-minute acquisition. Fifty-seven (60.6%) nodes measured 5 mm or less, including 29 (30.9%) seen only on the 15-minute acquisition. Thirty-one (33.0%) nodes measured 5.1-10 mm, including eight (25.8%) seen only on the 15-minute acquisition. Of the 17 subjects imaged for initial staging, 11 (64.7%) were upstaged as a result of the increased PET acquisition time (10 from N1 to N2 and one from N0 to N1). CONCLUSION: Longer PET acquisition times during PET/MRI for rectal cancer increases the number of FDG-avid lymph nodes detected without increasing scan time.

The Stability of Factors Influencing the Choice of Medical Specialty Among Medical Students and Postgraduate Radiology Trainees.

OBJECTIVE: To investigate whether general psychological motivating factors that guide career selection of a medical specialty differ over the course of medical school and to compare differences in motivating factors among students choosing "controllable" lifestyle specialties, students choosing "uncontrollable" lifestyle specialties, and a cohort of radiology residents. MATERIALS AND METHODS: An anonymous survey was distributed to first- through fourth-year medical students and radiology residents at a single institution. Participants were asked to select their top three of seven factors that most influenced their choice of medical specialty. Fourth-year students were asked to designate the specialty to which they had applied. RESULTS: The survey was distributed to 259 students and 47 radiology residents with a response rate of 93.8% (243 of 259) and 95.7% (45 of 47), respectively. The top three factors indicated by medical students were finding the daily work fulfilling, work-life balance, and interest in the subject. These top three factors were common to all medical student classes and did not differ between students choosing "controllable" versus "uncontrollable" fields. The factors uncommonly selected were similar personality to others in the field, attending income, competitiveness or prestige, and job market conditions. For radiology residents, the top three motivating factors were the same as for medical students. CONCLUSION: Three out of seven motivating factors were universally important to trainees, regardless of their stage of medical training or their selection of a controllable versus uncontrollable lifestyle specialty. These data suggest the variety of career choices made by students may not derive from differing underlying values.

PI-RADS v2 and ADC values: is there room for improvement?

PURPOSE: To determine the diagnostic accuracy of ADC values in combination with PI-RADS v2 for the diagnosis of clinically significant prostate cancer (CS-PCa) compared to PI-RADS v2 alone. MATERIALS AND METHODS: This retrospective study included 155 men whom underwent 3-Tesla prostate MRI and subsequent MR/US fusion biopsies at a single non-academic center from 11/2014 to 3/2016. All scans were performed with a surface coil and included T2, diffusion-weighted, and dynamic contrast-enhanced sequences. Suspicious findings were classified using Prostate Imaging Reporting and Data System (PI-RADS) v2 and targeted using MR/US fusion biopsies. Mixed-effect logistic regression analyses were used to determine the ability of PIRADS v2 alone and combined with ADC values to predict CS-PCa. As ADC categories are more practical in clinical situations than numeric values, an additional model with ADC categories of ≤ 800 and > 800 was performed. RESULTS: A total of 243 suspicious lesions were included, 69 of which were CS-PCa, 34 were Gleason score 3+3 PCa, and 140 were negative. The overall PIRADS v2 score, ADC values, and ADC categories are independent statistically significant predictors of CS-PCa (p < 0.001). However, the area under the ROC of PIRADS v2 alone and PIRADS v2 with ADC categories are significantly different in both peripheral and transition zone lesions (p = 0.026 and p = 0.03, respectively) Further analysis of the ROC curves also shows that the main benefit of utilizing ADC values or categories is better discrimination of PI-RADS v2 4 lesions. CONCLUSION: ADC values and categories help to diagnose CS-PCa when lesions are assigned a PI-RADS v2 score of 4.

Evaluating the performance of PI-RADS v2 in the non-academic setting.

PURPOSE: To evaluate the utility of PI-RADS v2 to diagnose clinically significant prostate cancer (CS-PCa) with magnetic resonance ultrasound (MR/US) fusion-guided prostate biopsies in the non-academic setting. MATERIALS/METHODS: Retrospective analysis of men whom underwent prostate multiparametric MRI and subsequent MR/US fusion biopsies at a single non-academic center from 11/2014 to 3/2016. Prostate MRIs were performed on a 3-Tesla scanner with a surface body coil. The Prostate Imaging Reporting and Data System (PI-RADS) v2 scoring algorithm was utilized and MR/US fusion biopsies were performed in selected cases. Mixed effect logistic regression analyses and receiver-operating characteristic (ROC) curves were performed on PI-RADS v2 alone and combined with PSA density (PSAD) to predict CS-PCa. RESULTS: 170 patients underwent prostate MRI with 282 PI-RADS lesions. MR/US fusion diagnosed 71 CS-PCa, 33 Gleason score 3+3, and 168 negative. PI-RADS v2 score is a statistically significant predictor of CS-PCa (P < 0.001). For each one-point increase in the overall PI-RADS v2 score, the odds of having CS-PCa increases by 4.2 (95% CI 2.2-8.3). The area under the ROC curve for PI-RADS v2 is 0.69 (95% CI 0.63-0.76) and for PI-RADS v2 + PSAD is 0.76 (95% CI 0.69-0.82), statistically higher than PI-RADS v2 alone (P < 0.001). The rate of CS-PCa was about twice higher in men with high PSAD (≥0.15) compared to men with low PSAD (<0.15) when a PI-RADS 4 or 5 lesion was detected (P = 0.005). CONCLUSION: PI-RADS v2 is a strong predictor of CS-PCa in the non-academic setting and can be further strengthened when utilized with PSA density.

Intraperitoneal metastases after transarterial embolization of hepatocellular carcinoma: An observational study.

PURPOSE: Transarterial embolization is frequently used to treat local hepatocellular carcinoma (HCC). While various complications are known to occur following transarterial embolization, only one prior case of peritoneal spread of HCC occurring shortly after transarterial chemoembolization has been reported. We present five cases of peritoneal spread of HCC following transarterial embolization (including bland embolization, conventional transarterial chemoembolization (TACE), and doxorubicin-eluting beads TACE) and identify features common among those cases. METHODS: Search of electronic radiology reports and images identified five patients with imaging before and after treatment of HCC with transarterial embolization and with newly developed peritoneal metastases after treatment. Various patient demographics and tumor characteristics were noted. RESULTS: The mean maximal diameter of the treated HCC tumors was 3.7 cm (range 1.4-11.9 cm). Three of the patients had ascites and treated tumors in the posterior right hepatic lobe, and all patients had subcapsular tumors treated with transarterial embolization before developing peritoneal metastases. The mean time from treatment with transarterial embolization to the development of peritoneal metastases was four months. CONCLUSIONS: Intraperitoneal metastatic disease should be considered a rare but potential complication of transarterial embolization of subcapsular HCC, particularly in patients with ascites and tumors that are in the posterior segments of the right lobe. This potential complication should perhaps be considered when planning transarterial HCC treatment, and radiologists interpreting imaging after transarterial embolization of HCC should assess for peritoneal metastases.

Radiologic assessment of fetal tracheal balloon occlusion.

Fetal endoscopic tracheal occlusion (FETO) is a novel technique to treat cases of isolated severe congenital diaphragmatic hernia (CDH). Although there are benefits of MRI over ultrasound in assessing lung volumes, it is unknown whether there are benefits of MRI for localizing the tracheal balloon. This is a retrospective study reviewing the imaging characteristics of FETO in patients who underwent both MRI and ultrasound exams done to localize tracheal balloons.

A novel approach for quantitation of nonderivatized sialic acid in protein therapeutics using hydrophilic interaction chromatographic separation and nano quantity analyte detection.

This paper describes a novel approach for the quantitation of nonderivatized sialic acid in glycoproteins, separated by hydrophilic interaction chromatography, and detection by Nano Quantity Analyte Detector (NQAD). The detection technique of NQAD is based on measuring change in the size of dry aerosol and converting the particle count rate into chromatographic output signal. NQAD detector is suitable for the detection of sialic acid, which lacks sufficiently active chromophore or fluorophore. The water condensation particle counting technology allows the analyte to be enlarged using water vapor to provide highest sensitivity. Derivatization-free analysis of glycoproteins using HPLC/NQAD method with PolyGLYCOPLEX™ amide column is well correlated with HPLC method with precolumn derivatization using 1, 2-diamino-4, 5-methylenedioxybenzene (DMB) as well as the Dionex-based high-pH anion-exchange chromatography (or ion chromatography) with pulsed amperometric detection (HPAEC-PAD). With the elimination of derivatization step, HPLC/NQAD method is more efficient than HPLC/DMB method. HPLC/NQAD method is more reproducible than HPAEC-PAD method as HPAEC-PAD method suffers high variability because of electrode fouling during analysis. Overall, HPLC/NQAD method offers broad linear dynamic range as well as excellent precision, accuracy, repeatability, reliability, and ease of use, with acceptable comparability to the commonly used HPAEC-PAD and HPLC/DMB methods.

CT pulmonary angiography in pregnant and postpartum women: low yield, high dose.

PURPOSE: To compare the diagnostic utility of computed tomography pulmonary angiography (CTPA) in pregnant/postpartum women with age-matched controls. MATERIALS: We performed a retrospective case-control series of pregnant/postpartum women and control women who underwent CTPA from 2008 to 2011. RESULTS: The study included 34 pregnant women, 16 postpartum women, and 50 controls. CTPAs were positive in 2% of pregnant/postpartum women and 16% of controls (P=.003). The main pulmonary artery mean opacification was 271 Hounsfield units (HU) for pregnant/postpartum women vs. 303 HU (P=.12). Radiation exposure was high in both groups but lower in pregnant/postpartum women, 10 vs. 14 mSv (P=.003). CONCLUSION: CTPA in pregnant and postpartum women had low yield and remained high dose.

Prevalence and significance of perivascular soft tissue surrounding the hepatic artery after liver transplantation.

OBJECTIVE: The objective of this study was to determine the prevalence and significance of perivascular soft tissue surrounding the hepatic artery on computed tomography (CT) after liver transplantation. MATERIALS AND METHODS: A total of 119 consecutive patients who underwent liver transplantation were retrospectively identified from a search of electronic medical records. Fourteen patients had histologic proof of posttransplant lymphoproliferative disease (PTLD). For each patient, the initial CT scan after transplantation, and the most recent CT scan if available, was analyzed for the presence of soft tissue in the porta hepatis region, particularly surrounding the transplanted hepatic artery. The hepatic artery was identified, and the maximum diameter of the soft tissue surrounding the vessel was measured and classified using the following scale: grade 0, none; grade 1, mild; grade 2, moderate; grade 3, moderate-large; and grade 4, large. RESULTS: Prevalence of perivascular soft tissue was 93% in the initial CT scans and follow-up studies. Comparing the initial and follow-up soft tissue measurements, 34% decreased, 62% were unchanged, and 4% increased. Using the Fisher exact test and a Mann-Whitney test, there was no statistically significant difference in the prevalence or diameter of perivascular soft tissue when comparing patients with pathologically proven PTLD and patients with no PTLD. Twenty-nine of the 119 patients underwent 68 positron emission tomography/CT scans in the time interval analyzed. Ninety percent of these patients had no abnormal fluorodeoxyglucose activity in the porta hepatis and portacaval regions. CONCLUSIONS: The presence of isolated perivascular soft tissue in patients after liver transplantation is a common finding and is not associated with lymphoproliferative disease.

Influence of a three-dimensional, microarray environment on human cell culture in drug screening systems.

We have used a modified 3D cellular microarray platform for the high-throughput analysis of growth, cytotoxicity, and protein expression profile of a human hepatocellular carcinoma cell line, HepG2, in alginate. The results obtained were compared to analogous studies in 2D and 3D environments at the microtiter scale. The antiproliferative effects of four drugs, tamoxifen, 5-fluorouracil, doxorubicin, and amitriptyline, were studied as a function of seeding density in the three different culture platforms. The chemosensitivity of HepG2 cells to all four compounds decreased substantially with increasing cell number in the 2D and 3D microtiter-based cultures, while no seeding density dependence was observed in the IC(50) values obtained in the 3D microarray culture platform. These results can be rationalized based on the development of confluence-dependent resistance in cultures where proliferation is restricted by cell-cell contacts and nutrient availability, as is the case for both of the microtiter-based cultures. Additionally, further development of an on-chip, in-cell immunofluorescence assay provided quantitative data on the levels of specific target proteins involved in proliferation, adhesion, angiogenesis and drug metabolism, and was used to compare expression profiles between 2D and 3D environments. The up-regulation of several CYP450 enzymes, ß1-integrin and vascular endothelial growth factor (VEGF) in the 3D microarray cultures suggests that this platform provides a more in vivo-like environment allowing cells to approach their natural phenotype.