The value of screening in siblings of patients with abdominal aortic aneurysm.

OBJECTIVES: This study aimed to determine the incidence of abdominal aortic aneurysm (AAA) in a large group of siblings of Australian AAA patients to determine if screening in this group is justified. METHODS: 1254 siblings of 400 index AAA patients were identified and offered aortic ultrasound screening. An age and sex matched control group was recruited from patients having abdominal CT scans for non-vascular indications. AAA was defined by an infrarenal aortic diameter of > or =3 cm or a ratio of the infrarenal to suprarenal aortic diameter of > or =2.0. A ratio of 1.0-1.5 was considered normal, and a ratio of >1.5 to <2.0 was considered ectatic. Aortic enlargement was defined as ectasia or aneurysm. RESULTS: 276 (22%) siblings could be contacted and agreed to screening or had previously been diagnosed with AAA. All 118 controls had normal diameter aortas. 55/276 siblings had previously been diagnosed with AAA. The remaining 221 siblings underwent ultrasound screening. Overall, 30% (84/276) had enlarged aortas (5% ectasia, 25% aneurysmal); 43% of male siblings (64/150) and 16% of females siblings (20/126). The incidence was 45% in brothers of female index patients, 42% in brothers of male patients, 23% in sisters of female patients, and 14% in sisters of male index patients. CONCLUSIONS: The overall incidence of aortic enlargement of 30% found in this study warrants a targeted screening approach with ultrasound for all siblings of patients with AAA. A similar targeted approach for screening of the children of AAA patients would also seem advisable.     

Efficacy and problems of bladder volume measurement using portable three dimensional ultrasound scanning device--in particular, on measuring bladder volume lower than 100ml

OBJECTIVES: Using a portable three dimensional ultrasound scanning device (The Bladder Scan BVI6100, Diagnostic Ultrasound Corporation), we examined measured values of bladder volume, especially focusing on volume lower than 100 ml. MATERIALS AND METHODS: A total of 100 patients (male: 66, female: 34) were enrolled in the study. We made a comparison study between the measured value (the average of three measurements of bladder urine volume after a trial in male and female modes) using BVI6100, and the actual measured value of the sample obtained by urethral catheterization in each patient. We examined the factors which could increase the error rate. We also introduced the effective techniques to reduce measurement errors. RESULTS: The actual measured values in all patients correlated well with the average value of three measurements after a trial in a male mode of the BVI6100. The correlation coefficient was 0.887, the error rate was--4.6 +/- 24.5%, and the average coefficient of variation was 15.2. It was observed that the measurement result using the BVI6100 is influenced by patient side factors (extracted edges between bladder wall and urine, thickened bladder wall, irregular bladder wall, flattened rate of bladder, mistaking prostate for bladder in male, mistaking bladder for uterus in a female mode, etc.) or examiner side factors (angle between BVI and abdominal wall, compatibility between abdominal wall and ultrasound probe, controlling deflection while using probe, etc). CONCLUSIONS: When appropriate patients are chosen and proper measurement is performed, BVI6100 provides significantly higher accuracy in determining bladder volume, compared with existing abdominal ultrasound methods. BVI6100 is a convenient and extremely effective device also for the measurement of bladder urine over 100 ml.     

Study of low bladder volume measurement using 3-dimensional ultrasound scanning device: improvement in measurement accuracy through training when bladder volume is 150 ml or less

PURPOSE: Using a Bladder Scan BVI6100 portable 3-dimensional ultrasound scanning device we examined measured values of bladder volume, especially focusing on volumes of 150 ml or less. MATERIALS AND METHODS: A total of 89 men and 71 women were enrolled in the study. We performed a comparison study between the measured value (the average of 3 bladder volume measurements after a trial in male and female modes) using the BVI6100 and the actual measured value determined by urethral catheterization in each patient. We examined factors that could increase the error rate and measuring techniques to decrease measurement errors. We also reviewed the training effects of measurement for a year. RESULTS: Actual measured values in all patients correlated well with the average value of 3 measurements after a trial of BVI6100 in male mode. The correlation coefficient was 0.941 (0.967 after a year), the mean +/- SD error rate was -2.0% +/- 22.0% (-2.0% +/- 13.8% after a year) and the average variation coefficient was 12.4 (7.6 after a year). It was found that measurement results using the BVI6100 were influenced by patient factors, including extracted edges between the bladder wall and urine, thickened bladder wall, irregular bladder wall, flattened bladder, mistaking the prostate for the bladder in male mode, mistaking the bladder for the uterus in female mode, etc, and examiner factors, including changes in the angle between the BVI6100 and the abdominal wall, compatibility between the abdominal wall and the ultrasound probe, controlling deflection while using the probe, etc. It was also found that measurement accuracy could be improved regarding patient and examiner factors by choosing appropriate patients and performing concise measurement procedures (training effects). CONCLUSIONS: When appropriate patients are chosen and proper measurement is performed, the BVI6100 provides significantly higher accuracy for determining lower bladder volume compared with existing abdominal ultrasound methods.     

Aortic diameter at age 65 in men with newly diagnosed type 2 diabetes

Objectives. Type 2 diabetes mellitus has been linked to a decreased risk for abdominal aortic aneurysm (aortic diameter ≥30?mm, AAA) development in men. The aim of this study was to evaluate if such an effect is detectable already around the time of diabetes diagnosis. Design. We cross-sectionally compared aortic diameter at ultrasound screening for AAA in 691 men aged 65 years with incipient or newly diagnosed type 2 diabetes (group A) with 18,262 65-year old control men without diabetes (group B). Results. Aortic diameter did not differ between groups (18.8[17.4–20.8] vs. 19.0[17.5–28.7] mm; p?=?0.43). AAA prevalence was 2.5% in group A and 1.5% in group B (p?=?.010). In logistic regression taking group differences in body mass index (BMI), smoking, presence of atherosclerotic disease and hypertension into account, the difference in AAA prevalence was no longer significant (p?=?.15). Among men in group A, C-peptide (r?=?.093; p?=?.034), but not HbA1c (r?=?.060; p?=?.24) correlated with aortic diameter. Conclusion. Among 65 year old men aortic diameter and AAA prevalence do not differ between those with newly diagnosed type 2 diabetes and those without diabetes. Putative protective effects of type 2 diabetes mellitus against aortic dilatation and AAA development therefore probably occur later after diagnosis of diabetes.     

Risk of developing an abdominal aortic aneurysm after ectatic aorta detection from initial screening

ObjectiveCurrent abdominal aortic aneurysm (AAA) surveillance guidelines lack any follow-up recommendations after initial abdominal aortic screening diameter of less than 3.0 cm. Some reports have demonstrated patients with late AAA formation and late ruptures after initial ultrasound screening detection of patients with an aortic diameter of 2.5 to 2.9 cm (ectatic aorta). The purpose of this study was to determine ectatic aorta prevalence, AAA development, rupture risk, and risk factor profile in patients with detected ectatic aortas in a AAA screening program.MethodsA retrospective chart review of all patients screened for AAA from January 1, 2007, to December 31, 2016, within a regional health care system was conducted. Screening criteria were men 65 to 75 years of age that smoked a minimum of 100 cigarettes in their lifetime. An ectatic aorta was defined as a maximum aortic diameter from 2.5 to 2.9 cm. An AAA was defined as an aortic diameter of 3 cm or greater. Patients screened with ectatic aortas who had subsequent follow-up imaging of the aorta with a minimum of 1-year follow-up were analyzed for associated clinical and cardiovascular risk factors. All data were collected through December 3,/2018. A logistic regression of statistically significant variables from univariate and χ² analyses were performed to identify risks associated with the development of AAA from an initially diagnosed ectatic aorta. A Cox proportional hazard model was used to assess survival data. A P value of less than .05 was considered statistically significant.ResultsFrom a screening pool of 19,649 patients, 3205 (16.3%) with a mean age of 72.1 ± 5.3 years were identified to have an ectatic aorta from January 1, 2007, to December 31, 2016. The average screening ectatic aortic diameter was 2.6 ± 0.1 cm. There were 672 patients (21.0%) with a mean age of 73.0 ± 5.7 years who received subsequent imaging for other clinical indications and 193 of these patients (28.7%) with ectatic aortas developed an AAA from the last follow-up scan (4.2 ± 2.5 years). The average observation length of all patients was 6.4 ± 2.9 years. No ruptures were reported, but 27.8% of deaths were of unknown cause. One patient had aortic growth to 5.5 cm or greater (0.15%). Larger initial screening diameter (P < .01), presence of chronic obstructive pulmonary disease (P < .01), and active smoking (P = .01) were associated with AAA development.ConclusionsPatients with diagnosed ectatic aortas from screening who are active smokers or have chronic obstructive pulmonary disease are likely to develop an AAA.     

The Validity of Ultrasonographic Scanning as Screening Method for Abdominal Aortic Aneurysm

OBJECTIVE: the sensitivity and specificity of screening for abdominal aortic aneurysms (AAAs) with ultrasonographic scanning (US) is unknown. The aim of the study was to validate US as screening test for AAAs. METHODS AND MATERIAL: 4176 (76.3%) of 5470 men aged 65-73 attended hospital-based US screening for an AAA at their local hospital. Two observers and one scanner were used. The maximal anterior-posterior (AP) of the dilated aorta, or 2 cm above the bifurcation, and at the crossing of left renal vein was recorded. In 50 cases, blinded measurements were carried out by two observers. An AAA was defined as an AP diameter greater than 29 mm. RESULTS: the standard deviation (s.d.) of the interobserver variability of the distal AP diameter was 0.84. The mean distal AP diameter was 17. 9 mm (s.d. 2.92). Combining these data, the estimated diagnostic sensitivity was 98.9%, the estimated diagnostic specificity was 99. 9%. The interobserver s.d. of the proximal AP diameter was 1.76. The mean proximal AP diameter was 18.4 mm (s.d. 2.45). Combining these data, the estimated diagnostic sensitivity was 87.4%, the estimated diagnostic specificity was 99.9%. CONCLUSION: US seems to be a valid screening method for AAA. Screening for proximal infrarenal aorta aneurysm remains acceptable because the majority of aortic diameters in this segment are so much smaller than the diameters that define an AAA.     

Prevalence of abdominal aortic aneurysm in Chinese patients with severe coronary artery disease

Background: The Asian population is believed to have lower incidence of abdominal aortic aneurysm (AAA), and hence, the benefit of screening is uncertain. The size of native aorta in Asians, which shall affect the definition of AAA, has also never been reported. Our study investigated the prevalence of AAA and the infra‐renal aortic diameter (AD) in Chinese patients with severe coronary artery disease. Methods: This is a prospective observational study of infra‐renal aortic size for patients who had coronary artery bypass surgery by ultrasound. The patients' demographics, important co‐morbidities and maximum AD were recorded. Results: The study included 624 consecutive Chinese patients (mean age = 63.2 years). The mean maximum infra‐renal AD was 17.5 mm for men and 14.8 mm for women. The presence of AAA was defined as maximum AD greater than 30 mm. The result was also compared with an alternate definition that defines AAA as maximum AD of greater than 1.5 times of the group's mean. Eleven patients had an AD greater than 30 mm, and the prevalence of AAA was only 1.8%. With AAA defined as maximum AD of 1.5 times greater than the group's mean, 19 patients had AAA. The prevalence of AAA in this high‐risk group would become 3% overall. Conclusion: The prevalence of AAA in Chinese patients was low, and the result did not support routine screening. The smaller mean infra‐renal AD in Chinese merits validation by large‐scale study and consideration when deciding threshold for small AAA repair in our locality.     

Comparison of abdominal aortic aneurysm diameter measurements obtained with ultrasound and computed tomography: Is there a difference?

OBJECTIVES: Accurate diameter measurements of abdominal aortic aneurysm (AAA) with both computed tomography (CT) and ultrasound (US) are essential for screening, planning surgical intervention, and follow-up after endovascular repair. Often there is a discrepancy between measurements obtained with CT and US, and neither limit of agreement (LOA) nor correlation between the two imaging methods has been clearly established. The purpose of this study was to assess the paired differences in AAA diameter measurements obtained with CT and US in a large national endograft trial. METHODS: CT and US measurements were obtained from an independent core laboratory established to assess imaging data in a national endograft trial (Ancure; Guidant, Menlo Park, Calif). The study included only baseline examinations in which both CT and US measurements were available. Axial CT images and transverse US images were assessed for maximal AAA diameter and recorded as CT(max) and US(max), respectively. Correlations and LOA were performed between all image diameters, and differences in their means were assessed with paired t test. RESULTS: A total of 334 concurrent measurements were available at baseline after endovascular repair. CT(max) was greater than US(max) in 95% (n = 312), and mean CT(max) (5.69 +/- 0.89 cm) was significantly larger (P <.001) than mean US(max) (4.74 +/- 0.91 cm). The correlation coefficient between CT(max) and US(max) was 0.705, but the difference between the two was less than 1.0 cm in only 51%. There was less discrepancy between CT(max) and US(max) for small AAA (0.7 cm, 15.3%) compared with medium (0.9 cm, 17.9%) and large (1.46 cm, 20.3%) AAA; however, the difference was not statistically significant. LOA between CT(max) and US(max) (-0.45-2.36 cm) exceeded the limits of clinical acceptability (-0.5-0.5 cm). Poor LOA was also found in each subgroup based on AAA size. CONCLUSIONS: Maximal AAA diameter measured with CT is significantly and consistently larger than maximal AAA diameter measured with US. The clinical significance of this difference and its cause remains a subject for further investigation.     

A prospective study of a hand-held ultrasound device in abdominal aortic aneurysm evaluation

PURPOSE: Effective treatment of abdominal aortic aneurysm (AAA) requires both early detection and timely repair to reduce aneurysm-related mortality. The purpose of this prospective study was to evaluate the utility of a hand-held ultrasonography (US) device in AAA screening in a Veterans Affairs vascular surgical service. METHODS: During a 16-month period, patients with risk factors for AAA were evaluated in a blinded fashion with a hand-held US device performed by physicians. A conventional abdominal duplex US examination was also performed by a certified vascular ultrasonographer. Results of the hand-held US was compared with the conventional duplex US examination. RESULTS: A total of 104 patients were evaluated (97 men, mean age 67 +/- 6.3 years). The mean times for hand-held and conventional duplex US examinations were 5.3 +/- 3.2 minutes and 3.1 +/- 2.4 minutes (not significant), respectively. Using the conventional duplex US as a reference, the sensitivity and specificity of the hand-held device in detecting a AAA were 93% and 97%, respectively. The positive and negative predictive values of the hand-held device were 89% and 98%, respectively. The likelihood ratios of positive and negative tests of the hand-held US device examination were 82 and 0.14, respectively. The diagnostic accuracy of the hand-held US device as compared with the conventional duplex US was 98%. CONCLUSIONS: A hand-held portable US device is effective and accurate in AAA screening with results comparable to the conventional abdominal duplex examination. Moreover, hand-held portable US for AAA screening can be performed expeditiously during physical examination. It should be used as an extension in routine physical examination in vascular patients.     

Is assessment of popliteal artery diameter in patients undergoing screening for abdominal aortic aneurysms a worthwhile procedure.

PURPOSE: The aim of this study was to assess whether screening of popliteal arteries in patients undergoing ultrasound screening of their abdominal aortas was worthwhile. METHODS: All male patients undergoing ultrasound screening for abdominal aortic aneurysm (AAA) during the period February 2000 to June 2002 were offered scanning of their popliteal arteries. All scans were performed by a single, trained operator using a Sonosite 180. RESULTS: Four hundred and forty-nine patients underwent screening and thus 898 popliteal arteries were assessed. The mean aortic diameter was 2.1 standard deviations (SD) 0.5 cm and the upper limit of normal (2 SD) was 2.7 cm. The mean diameter of the popliteal arteries was 0.74 SD 0.11 and the upper limit of normal was 0.96 cm. Thirty patients had aortic diameters greater than 2.5 cm (ectatic or aneurysmal aortas) but based on a popliteal diameter of 2 cm, no popliteal aneurysms were detected. However, 39 (4.3%) popliteal arteries measured > or = 1 cm (> mean+2 SD); 3/60 (5%) in the ectatic/AAA subgroup and 36/838 (4.3%) in the non-AAA subgroup. CONCLUSIONS: This study has shown that, using conventional definitions, the imaging of popliteal arteries during screening for AAAs does not detect any popliteal aneurysms and is thus of limited value. However, if a definition of popliteal aneurysm of > or = 1 cm (based on mean+2 SD) is used then 39/898 (4.3%) of arteries would be regarded as having abnormal diameters and may require surveillance.     

Screening and ultrasound surveillance of large abdominal aortic aneurysms do not improve suitability for endovascular repair

OBJECTIVE: The effect of population screening for abdominal aortic aneurysm (AAA) disease on morbidity and mortality has been comprehensively studied and reported. However, the effect of early AAA detection on suitability for endovascular aneurysm repair (EVAR) remains unknown. Considering the importance of such an effect on future health economics, we sought to assess the possible effect of AAA ultrasound surveillance on suitability for EVAR. METHODS: This was a prospective cohort study. From January 2002 to August 2003, consecutive AAA patients selected for open elective repair were placed into one of two groups according to mode of presentation. The first group included patients referred from a local well-established AAA ultrasound screening and surveillance program (ultrasound surveillance [AAA-S] group). The second group included patients referred from neighboring unscreened regions with incidentally diagnosed AAA (incidental [AAA-I] group). All patients underwent preoperative computed tomographic angiography. By using three-dimensional reconstruction software, computed tomographic images were assessed by two blinded observers for suitability for EVAR by using the criteria for a modular endovascular device. RESULTS: Of 74 patients included in the study, 41 were in the AAA-S group, and 31 were in the AAA-I group. The median aneurysm diameter was 72.3 mm (range, 50.7-83.7 mm) for AAA-I and 65 mm (range, 50.7-79.2 mm) for AAA-S (P < .47). Suitability for EVAR was 41% in the AAA-S group and 45% in the AAA-I group (P < .47). CONCLUSIONS: Early detection and surveillance of AAA does not seem to increase suitability for EVAR. Suitability for EVAR seems to be determined early on in an aneurysm's life. On the basis of current device technology, referral for intervention from an AAA surveillance program may need to be initiated at a size well below 5.5 cm if an increase in EVAR suitability is to be expected.     

Influence of diagnostic criteria on the prevalence of abdominal aortic aneurysm

PURPOSE: We studied the prevalence of abdominal aortic aneurysm (AAA) in a population with high incidences of cardiovascular diseases and analyzed how the prevalence varies according to methodology and criteria. METHODS: All men and women aged 65 to 75 years who lived in the Norsj? municipality in northern Sweden were invited to undergo an ultrasound scanning (US) examination. Those with an aortic diameter of 28 mm or more or with poor visibility on US were examined with computed tomography scanning (CT). Various recommended AAA definitions, two diagnostic methods (US and CT), and two diameters (maximum and anteroposterior) were analyzed. RESULTS: Of 555 people invited to participate in the study, 504 accepted (248 men and 256 women; 91%). Eight subjects had undergone surgery for an AAA. Ninety-two subjects underwent CT. The mean maximum infrarenal aortic diameter was 24.6 mm (by means of US). Depending on diagnostic criteria, the AAA prevalence was 3.6% to 16.9% in men and 0.8% to 9.4% in women. Depending on which previous study was used as a comparison and the definition of AAA and diagnostic technique used, the prevalence in this study was 1.3 to 4.0 times higher for men and 2.0 to 5.8 times higher for women. CONCLUSION: In a region in which residents have a high risk for cardiovascular disease, we found the highest prevalence of AAA ever reported within a population. The prevalence highly depends on methodology and diagnostic criteria, with a 10-fold variation. Detailed defined criteria are necessary to permit comparisons between studies: the number of individuals who have undergone surgery for AAA and whether they are included, the prevalence in 5- and 10-year age intervals, attendance rate, visibility, which diameter(s) is measured, and the prevalences with as many as possible of the four described definitions of AAA. The etiology of the high prevalence of AAA in this population needs to be investigated further.     

Abdominal aortic aneurysm rupture rates: A 7-year follow-up of the entire abdominal aortic aneurysm population detected by screening

Purpose: The goal of the current study was to identify the risk of rupture in the entire abdominal aortic aneurysm (AAA) population detected through screening and to review strategies for surgical intervention in light of this information. Methods: Two hundred eighteen AAAs were detected through ultrasound screening of a family practice population of 5394 men and women aged 65 to 80 years. Subjects with an AAA of less than 6.0 cm in diameter were followed prospectively with the use of ultrasound, according to our protocol, for 7 years. Patients were offered surgery if symptomatic, if the aneurysm expanded more than 1.0 cm per year, or if aortic diameter reached 6.0 cm. Results: The maximum potential rupture rate (actual rupture rate plus elective surgery rate) for small AAAs (3.0 to 4.4 cm) was 2.1% per year, which is less than most reported operative mortality rates. The equivalent rate for aneurysms of 4.5 to 5.9 cm was 10.2% per year. The actual rupture rate for aneurysms up to 5.9 cm using our criteria for surgery was 0.8% per year Conclusion: In centers with an operative mortality rate of greater than 2%, (1) surgical intervention is not indicated for asymptomatic AAAs of less than 4.5 cm in diameter, and (2) elective surgery should be considered only for patients with aneurysms between 4.5 and 6 cm in diameter that are expanding by more than 1 cm per year or for patients in whom symptoms develop. In centers with elective mortality rates of greater than 10% for abdominal aortic aneurysm (AAA) repair, the benefit to the patient of any surgical intervention for an asymptomatic AAA of less than 6.0 cm in diameter is questionable. (J Vasc Surg 1998;28:124-8.)     

Intra- and interobserver variability in the measurements of abdominal aortic and common iliac artery diameter with computed tomography. The Troms? study.

OBJECTIVES: to assess intra- and interobserver variability in the measurement of aortic and common iliac artery diameter by means of computed tomography (CT). DESIGN: reproducibility study. MATERIAL AND METHODS: three radiologists performed measurements of aortic diameter at five different levels and of both common iliac arteries with CT. Fifty-nine subjects were examined, 29 with and 30 without abdominal aortic aneurysms (AAA) as assessed by ultrasound. RESULTS: intraobserver variability varied between radiologists, measurement plane (anterior-posterior vs transverse) and measurement level. The interobserver variability was markedly higher at the bifurcation than at the suprarenal level and higher than intraobserver variability for measurements at all levels. Both intraobserver and interobserver variability increased with increasing vessel diameter and were largest in patients with AAA. The absolute intraobserver difference of the maximal infrarenal aortic diameter was 2mm or less in 94% of intraobserver pairs. The corresponding interobserver difference was 82%. CONCLUSIONS: interobserver variability of CT measurements of aortic and common iliac artery diameter is not negligible and should be taken into account when making clinical decisions. When assessing change in aortic diameter, previous CT-scans should be reviewed simultaneously as a routine to exclude interobserver variability.     

Screening for abdominal aortic aneurysm and occlusive peripheral vascular disease in Japanese residents

To evaluate the prevalence of abdominal aortic aneurysm (AAA) and occlusive peripheral vascular disease (PVD) in Japanese residents, and to examine the correlations between these diseases and the risk factors of atherosclerosis, 348 residents of a village in central Japan aged between 60 and 79 years were screened. The screening for AAA was performed using ultrasonography (US) and that for PVD was performed by palpation and Doppler US. No AAA was found, and a right common iliac arterial aneurysm was detected in a 79-year-old man (0.3%). The mean diameter of the infrarenal abdominal aorta was 18.7 mm and an abdominal aorta of 25 mm or greater in diameter was seen in 16 participants (4.6%), all of whom need to be followed up. PVD was suspected in two patients (0.6%) with a low ankle brachial pressure index. Of a total of five patients diagnosed or suspected of having a common iliac arterial aneurysm or PVD, four (80%) had at least one risk factor for atherosclerosis. Thus, we conclude that Japanese residents with risk factors predisposing them to atherosclerosis such as hypertension, obesity, abnormal serum lipid levels, and a history of smoking should be selectively screened for AAA and PVD due to the low prevalence of these diseases and from the viewpoint of cost-effectiveness.     

Is ultrasound more accurate than axial computed tomography for determination of maximal abdominal aortic aneurysm diameter?

OBJECTIVE(S): Clinical assessment of maximal abdominal aortic aneurysm (AAA) diameter assumes clinical equivalency between ultrasound (US) and axial computed tomography (CT). Three-dimensional (3D) CT reconstruction allows for the assessment of AAA in the orthogonal plane and avoids oblique cuts due to AAA angulation. This study was undertaken to compare maximal AAA diameter by US, axial CT, and orthogonal CT, and to assess the effect that AAA angulation has on each measurement. METHODS: Maximal AAA diameter by US (US(max)), axial CT (axial(max)), and orthogonal CT (orthogonal(max)) along with aortic angulation and minor axis diameters were measured prospectively. Spiral CT data was processed by Medical Media Systems (West Lebanon, NH) to produce computerized axial CT and reformatted orthogonal CT images. The US technologists were blinded to all CT results and vice versa. RESULTS: Thirty-eight patients were analyzed. Mean axial(max) (58.0 mm) was significantly larger (P<0.05) than US(max) (53.9 mm) or orthogonal(max) (54.7 mm). The difference between US(max) and orthogonal(max) (0.8 mm) was insignificant (P>0.05). When aortic angulation was <==25 degrees, axial(max) (55.3 mm), US(max) (54.3 mm), and orthogonal(max) (54.1 mm) were similar (P>0.05); however, when aortic angulation was >25 degrees, axial(max) (60.1 mm) was significantly larger (P<0.001) than US(max) (53.8 mm) and orthogonal(max) (55.0 mm). The limits of agreement (LOA) between axial(max) and both US(max) and orthogonal(max) was poor and exceeded clinical acceptability (+/-5 mm). The variation between US(max) and orthogonal(max) was minimal with an acceptable LOA of -2.7 to 4.5 mm. CONCLUSION: Compared to axial CT, US is a better approximation of true perpendicular AAA diameter as determined by orthogonal CT. When aortic angulation is greater than 25 degrees axial CT becomes unreliable. However, US measurements are not affected by angulation and agree strongly with orthogonal CT measurements.     

Accuracy and precision of a new portable ultrasound scanner,the BME-150A,in residual urine volume measurement: a comparison with the BladderScan BVI 3000

The objective of the study was to determine the relative accuracy of a new portable ultrasound unit, BME-150A, and the BladderScan BVI 3000, as assessed in comparison with the catheterized residual urine volume. We used both of these machines to prospectively measure the residual urine volumes of 89 patients (40 men and 49 women) who were undergoing urodynamic studies. The ultrasound measurements were compared with the post-scan bladder volumes obtained by catheterization in the same patients. The ultrasounds were followed immediately (within 5 min) by in-and-out catheterizations while the patients were in a supine position. There were a total of 116 paired measurements made. The BME-150A and the BVI 3000 demonstrated a correlation with the residual volume of 0.92 and 0.94, and a mean difference from the true residual volume of 7.8 and 3.6 ml, respectively. Intraclass correlation coefficients for the accuracy of the two bladder scans were 0.90 for BME-150A and 0.95 for BVI 3000. The difference of accuracy between the two models was not significant (p = 0.2421). There were six cases in which a follow-up evaluation of falsely elevated post-void residual urine volume measurements on the ultrasound studies resulted in comparatively low catheterized volumes, with a range of differences from 66 to 275.5 ml. These cases were diagnosed with an ovarian cyst, uterine myoma, or uterine adenomyosis on pelvic ultrasonography. The accuracy of the BME-150A is comparable to that of the BVI 3000 in estimating the true residual urine volumes and is sufficient enough for us to recommend its use as an alternative to catheterization.     

Negative association between infra-renal aortic diameter and glycaemia: the Health in Men Study.

OBJECTIVE: There is evidence of a negative association between diabetes and abdominal aortic aneurysm (AAA). The aim of this study was to assess whether there is a similar relationship between both diabetes and glucose level, and infra-renal aortic diameter throughout its range. DESIGN AND METHODS: Infra-renal aortic diameter was measured using ultrasound in 12,203 men aged 65-83 years as part of a trial of screening for AAA. A range of cardiovascular risk factors were also assessed. In a follow-up study, fasting serum glucose was measured in 2,859 non-diabetic men. Aortic diameter was logarithmically transformed and treated as both a continuous and categorical variable in stepwise multivariate linear and logistic models. RESULTS: The median aortic diameter was slightly smaller in the diabetic men (21.3+/-3.9 vs 21.6+/-3.8, P<0.0001). There was an independent negative association between diabetes and AAA (OR 0.79, 95% CI: 0.63,0.98), and an inverse correlation (Coefficient: -0.0064, p=0.0024) between fasting glucose and aortic diameter in non-diabetic men. CONCLUSIONS: Diabetes is inversely associated with both AAA and aortic diameter in men over 65 years. This association is independent of other risk factors for AAA. Aortic diameter also has an inverse relationship with fasting glucose concentrations in men without diabetes.     

A screening program to identify risk factors for abdominal aortic aneurysms.

BACKGROUND: We aimed to explore the feasibility of a nurse-supervised aneurysm screening program to identify any independent risk factors for abdominal aortic aneurysm (AAA) formation in high-risk patients. METHODS: We conducted a prospective observational study of 90 male patients in a university- affiliated hospital in southern Ontario. The patients were prospectively evaluated and all underwent abdominal ultrasonography, with the main outcome measure being detection of an AAA. RESULTS: AAAs were identified in 18 patients (20%) and had a mean diameter of 3.6 (range 2.8-6.0) cm. A separate analysis was performed to identify risk factors for the presence of an aneurysm. The presence of carotid artery disease proved to be the only statistically significant independent predictor of the presence of AAA (odds ratio 2.23, 95% confidence interval 1.76-2.56). CONCLUSIONS: This study confirms the feasibility of a nurse-supervised AAA screening program, and on the basis of these results we recommend ultrasonographic screening for AAA in patients with a history of carotid artery disease.     

Screening for abdominal aortic aneurysm with electronic clinical reminders

Background

Based on randomized, population-based screening protocols, a single ultrasound examination reduces mortality from an abdominal aortic aneurysm (AAA) by facilitating elective surgical intervention before rupture. Ultrasound screening is accurate, noninvasive, inexpensive, and cost effective. By using a comprehensive electronic medical record, we inquired whether an age-prompted clinical reminder would facilitate the detection of AAA.

Methods

The AAA risk screen was installed in May 2007 via a computerized patient record system prompt for male veterans ages 65 to 75 who ever smoked. This abbreviated ultrasound examination uses a 3.5- to 4-MHz scan head, measures anteroposterior and transverse planes, and reports the largest infrarenal aortic diameter.

Results

Of 1437 examinations there were 73 AAAs of 3.0-cm diameter or larger (5.1%); 33 AAAs of 4.0-cm diameter or larger (2.3%); 15 AAAs of 5.0-cm diameter or larger (1.0%); and 11 AAAs of 5.5-cm diameter or larger (.77%). Fifty (68%) received counseling for abnormal findings.

Conclusions

Recognition of newly diagnosed AAA compared favorably with that of previous screening studies. Electronic clinical reminders identify undiagnosed, life-threatening AAAs before rupture. Immediate counseling is available in the vascular setting.