Low calorie commercial sugar is a sensitive marker of glomerular filtration rate

BACKGROUND: Glomerular filtration rate (GFR) in humans and animals might be determined with precision by measuring the clearance of an ideal marker, such as inulin. However, the use of inutest, an inulin analog, is limited by its cost and accessibility. The present study tested whether low calorie commercial sugar (LC sugar) can be used to measure GFR during normal and renal dysfunction. METHODS: Two groups of 6 male Wistar rats weighing 300 to 350 g were included. One group was treated with a daily dose of cyclosporine (CsA) 30 mg/kg subcutaneously for 7 days and the other group was formed by nontreated control rats. In one half of each group, GFR was evaluated by using inutest and in the other half by using LC sugar. GFR was also evaluated by using a wide LC sugar plasma concentration range in an additional group. RESULTS: In nontreated rats, the mean GFR evaluated with LC sugar was 2.2 +/- 0.1 mL/min. This value is equal to that obtained with inutest: 2.3 +/- 0.1 mL/min. CsA administration produced a significant reduction of renal blood flow and renal function. The GFR reduction induced by CsA was similarly determined by both LC sugar and inutest to be at 1.0 +/- 0.2 and 1.1 +/- 0.2 mL/min (P= NS), respectively. In addition, GFR did not change when LC sugar plasma concentration gradually increased. CONCLUSION: Our results show that in both normal and pathophysiologic conditions, LC sugar is a good marker of GFR similar to the gold standard inutest.     

Automated volumetry at CT colonography: a phantom study

RATIONALE AND OBJECTIVES: To assess the performance of a computer-aided detection (CAD) algorithm for measuring polyp-like structures on CT colonography (CTC) images of a phantom. MATERIALS AND METHODS: We constructed a Plexiglas phantom to which we affixed a series of idealized Plexiglas polyp-like objects, including spheres and hemispheres. We imaged the phantom in a four-channel detector CT scanner at a 1.3 mm slice thickness with a reconstruction interval of 0.6 mm, using combinations of 100 mAs, 30 mAs, horizontal and vertical orientation. For each set of CT images, the interior surface of the phantom was segmented. The CAD algorithm was applied to the resulting surface to identify the polypoid regions of interest and to calculate their volume and maximum linear dimension. Calculated values were then compared with actual values to yield percent error in each measurement. RESULTS: The mean error in volume for the subgroups of spheres and hemispheres was 3% and 5% respectively. Mean error in linear dimension was approximately 2% for both shape subgroups. All CAD-calculated values were closely correlated with their respective actual values. Parameter selection did not significantly affect the accuracy of the calculated measurements. CONCLUSIONS: Our CAD software accurately measured the greatest linear dimension and the volume of each of the polyp-like structures in our phantom. Results were largely independent of phantom orientation and the CT exposure factors.     

Use of 3D imaging in CT of the acute trauma patient: impact of a PACS-based software package

To evaluate the impact of a picture archiving and communication systems (PACS)–based software package on the requests for 3D reconstructions of multidetector CT (MDCT) data sets in the emergency radiology of a level 1 trauma center, we reviewed the number and type of physician requests for 3D reconstructions of MDCT data sets for patients admitted after sustaining multiple trauma, during a 12-month period (January 2003–December 2003). During the first 5 months of the study, 3D reconstructions were performed in dedicated workstations located separately from the emergency radiology CT interpretation area. During the last 7 months of the study, reconstructions were performed online by the attending radiologist or resident on duty, using a software package directly incorporated into the PACS workstations. The mean monthly number of 3D reconstructions requested during the two time periods was compared using Students t test. The monthly mean ± SD of 3D reconstructions performed before and after 3D software incorporation into the PACS was 34±7 (95% CI, 10–58) and 132±31 (95% CI, 111–153), respectively. This difference was statistically significant (p<0.0001). In the multiple trauma patient, implementation of PACS-integrated software increases utilization of 3D reconstructions of MDCT data sets.This paper has been accepted for presentation at the 15th Annual Scientific Meeting of the ASER in Montreal, Canada, September 8–11, 2004     

Hand involvement in paraneoplastic syndrome: a case report

Cutaneous paraneoplastic syndromes are skin and mucous membrane changes that are associated with cancer. We report a previously healthy 76-year-old man who developed marked finger and thumb contracture, pain, and hypersensitivity of both hands who was diagnosed subsequently as having gastric carcinoma with colonic metastasis. After the gastrointestinal tumors were resected the finger and thumb contracture lessened and the pain eased. Both the temporal relationship between the changes in the hand and the neoplasm and the improvement after resection suggest a paraneoplastic syndrome.     

Large pseudoaneurysm of left ventricle following cardiac surgery

A 75-year old female patient, with previous inferior acute myocardial infarction (AMI) in December 2000, was admitted in April 2001 with angina and heart failure. Transthoracic echocardiography (TTE) was suggestive of a postero-inferior pseudoaneurysm (PA) of the left ventricle (LV), with 61x49 mm. of size and mitral regurgitation. Cardiac catheterization was suspected of a PA of the LV and revealed a three vessels coronary artery disease. On 20th April she was submitted to cardiac surgery with resection of a large LV aneurysm (AN) and triple coronary artery bypass surgery. Afterwards, she was on NYHA class III and subsequent TTE and transesophagic echocardiography (TEE) were suggestive of a 90x60 mm LV posterior PA (confirmed by nuclear magnetic resonance) and severe mitral regurgitation, with good LV systolic function. She underwent a new cardiac surgery on 31st May 2002, with resuturing of the LV postero-inferior wall patch and removal of the PA. The patient is in good condition and on NYHA functional class I-II.     

American Society of Diagnostic and Interventional Nephrology Section Editor: Stephen Ash: Does Catheter Insertion by Nephrologists Improve Peritoneal Dialysis Utilization? A Multicenter Analysis

In contrast to hemodialysis (HD), peritoneal dialysis (PD) remains an underutilized form of renal replacement therapy in the United States. Although a variety of factors have been deemed responsible, timely insertion of a PD catheter may also be a contributory factor. We conducted a multicenter analysis to examine whether the establishment of a program for PD catheter insertion by nephrologists has a positive impact on the growth in the number of patients using PD. Data for catheter insertion performed by nephrologists were collected from three centers. Any change in the prevalent PD population at each respective center was compared to the number of PD patients during the period having the traditional surgical approach. Nephrologists at the three centers used the peritoneoscopic technique and performed catheter insertion under local anesthesia. In center 1, the PD population remained stable at between 38 and 45 patients (approximately 16% of the total end-stage renal disease [ESRD] population) from 1993 to 2001. Nephrologists initiated a program for PD catheter insertion in 2001. The number of PD patients has increased to 101 (32% of the ESRD population). In center 2, the PD population remained stable at between 70 and 78 patients (approximately 17%) between 1988 and 1990. Catheter insertion by interventional nephrologists began in 1991. The number of PD patients has increased to 125 (22%). In center 3, the PD population remained at 20-30 patients (approximately 18%) between 1988 and 1991. Catheter placement by nephrologists was initiated in 1991. The number of PD patients increased to 97 (27%). Catheter insertion by interventional nephrologists was suspended in 2001. The number of PD patients has gradually declined to 25 (6%). This study suggests that catheter insertion by the nephrologist can have a positive impact on the utilization of PD.