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.     

Wie ist die Umsetzung eines AAA-Screening-Programms in Deutschland möglich?

Background

Screening programs are currently of upmost importance in health politics. Large international studies of abdominal aortic aneurysm (AAA) screening programs showed a significant decrease in aneurysm-dependent mortality. In view of these findings, AAA screening programs have been implemented in various countries with variable healthcare infrastructures.

Aim

In Germany a screening program also urgently needs to be introduced but realization depends on a variety of factors. This article presents the health service system in Germany and compares it with countries that have already established AAA screening programs. A comparative analysis of factors influencing possible conditions for introducing an AAA screening program in Germany was carried out.

Material and methods

A nationwide written survey of 2000 representatively chosen German family practitioners was carried out in order to evaluate their knowledge of AAAs, the availability of ultrasound devices and the motivation for performing the screening.

Results

A majority of German family practitioners possess the required knowledge of AAAs and the ultrasound skills to perform the screening. In addition, more than two thirds were in possession of an ultrasound device. Most practitioners were confident of performing a screening and would participate in a nationwide screening of AAAs.

Conclusion

The conditions for a nationwide implementation of an AAA screening program performed with the help of general practitioners are fulfilled, considering knowledge, motivation und ultrasound availability. Owing to the lower logistic and financial expenditures in comparison to foreign AAA screening programs, the implementation by general practitioners seems to be advantageous.     

Community-Based, Nonprofit Organization-Sponsored Ultrasonography Screening Program for Abdominal Aortic Aneurysms Is Effective at Identifying Occult Aneurysms

Early diagnosis of abdominal aortic aneurysm (AAA), prior to rupture, is vital for optimizing patient survival. An abdominal ultrasonography examination of an asymptomatic individual to check for the presence of an AAA, however, is not presently reimbursed by health insurance in the United States. This article reports the results of one nonprofit, community-based screening program, run by Aneurysm Outreach, Inc. (AOI; www.alink.org). AOI offered free screening for AAA to anyone who met the criteria of being (1) over 60 years old; (2) over 50 years old, male, and with positive family history for AAA; or (3) over 55 years old, female, and with positive family history for AAA. AOI organized 21 ultrasonographic screening events between September 2001 and November 2004, and the number of participants per event varied from 24 to 240. Altogether 3,088 individuals met the screening criteria and 22 of them were already known to have AAAs. Thirty-six (1.2%) individuals were excluded from the final analysis due to poor quality of the ultrasonographic images. Among the remaining 3,030 individuals, a dilatation of the aorta was detected and confirmed in 61 (2.0%) individuals, in 4.3% of the screened males and in 0.6% of the screened females. Thirteen individuals had their AAAs repaired surgically. The frequencies of males and current smokers were significantly higher in the AAA group than in the group with normal-size aorta (male AAA 83.6% vs. normal 42.0%, p < 0.0001; smoker AAA 54.9% vs. normal 18.1%, p < 0.0001). The mean age was significantly higher in the AAA group than in the group with normal-size aorta (AAA 71.0 ± 6.2 vs. normal 68.4 ± 7.0, p = 0.005). In conclusion, the results of this community-based free ultrasonographic screening program are in agreement with randomized controlled screening programs and emphasize the need for systematic screening programs and the importance of finding individuals harboring AAAs before their rupture.     

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.     

Clinical validation of three-dimensional ultrasound for abdominal aortic aneurysm

ObjectiveThree-dimensional ultrasound (3D-US) examination is a relatively new modality that can be used for abdominal aortic aneurysm (AAA) surveillance, and may offer improved reproducibility over conventional two-dimensional ultrasound (2D-US) examination. The aim of this study was to evaluate the interoperator reproducibility of maximum anterior-to-posterior diameter by nonphysician ultrasound technicians in a typical vascular laboratory setting, on patients with infrarenal AAAs using 3D-US and 2D-US examination.MethodsA total of 134 consecutive patients with asymptomatic infrarenal AAAs were screened. Of the 134 patients, 28 (21%) were screen failures. From the remaining 106 patients, 3 (2.8%) had missing data and 13 (12.3%) had technically unacceptable image quality. As a result, 90 patients were included for final analysis. Ultrasound image acquisitions were performed during the single visit. The 2D-US images were evaluated at the time of examination by the respective ultrasound technicians who acquired them. All 3D-US images were evaluated offline by both ultrasound technicians after a wash-out period of at least 6 weeks.ResultsExcellent interoperator reproducibility was observed for measuring maximum diameter using 3D-US (intraclass correlation coefficient, 0.97), and good agreement among ultrasound technicians (mean difference, −0.08 mm; limits of agreement, −3.17; 3.00 mm). When using 3D-US examination, 74 of the 90 patients (82%) were estimated within 2 mm of interoperator variability. Of 90 patients, 52 (58%) were estimated to be within the same variability by 2D-US examination. Estimating AAA diameter using 3D-US was superior to 2D-US with respect to interoperator reproducibility.ConclusionsBoth 3D-US and 2D-US examination demonstrated good reproducibility among two vascular ultrasound technicians with superior agreement from 3D-US examination. The present results support the broader use of 3D-US in standard AAA surveillance programs.     

French women from multiplex abdominal aortic aneurysm families should be screened

BACKGROUND: Multiplex abdominal aortic aneurysm families (MAAAFs) (> or =1 subject plus the proband) represent 1% to 34% of abdominal aortic aneurysm (AAA), but the percentage in France is unknown. METHOD: The MAAAF rate was retrospectively defined by analysis of 3 groups: 72 of 104 consecutive individuals undergoing AAA surgery during 1994, 24 of 53 women and 35 of 76 men with giant (> or =9 cm) AAA operated on during 1986 to 1994. MAAAF characteristics were determined based on 10 families issued from these 3 groups and 34 others identified nationwide. Data were obtained from a standardized questionnaire for probands and relatives, detailed pedigrees of each family, and computed tomography (CT) scans without contrast medium of the aorta and lower limb arteries for first-degree relatives > or =40-year-of age. RESULTS: The MAAAF rate was 4.2% for the consecutive-surgery patients (proband M/F ratio, 17:1; mean age at surgery, 68.5 +/- 8.5 years). CT detected no additional AAA among them (screened individuals M/F ratio, 0.63; mean age, 54.0 +/- 11.2 years). MAAAF rates were 8.3% and 14.3% for the women's and giant-AAA groups with CT screening, respectively. Characteristics were investigated in 104 affected subjects from 44 MAAAFs: female relatives were more often affected than probands (P < 0.025). Compared with men, affected female relatives were significantly older at diagnosis and surgery (P < 0.05 and P < 0.02, respectively), as were affected women (P < 0.02 and P < 0.01, respectively). CT scan screening identified significantly more AAA and abdominal aortic dilatations among the 44 MAAAFs than the consecutive-surgery group (5 and 4, respectively; P < 0.001). CONCLUSION: Although the MAAAF rate seems low in France, women from MAAAF were affected more often and later, suggesting that they should be screened.     

Measuring abdominal aortic diameters in routine abdominal computed tomography scans and implications for abdominal aortic aneurysm screening

Objective

This study aimed to determine the prevalence and relevance of incidental abdominal aortic aneurysm (AAA) on routine abdominal computed tomography (CT) and to audit the performance of radiologists to identify and report AAA.

Color-flow duplex ultrasound scan versus computed tomographic scan in the surveillance of endovascular aneurysm repair

OBJECTIVE: The purpose of this study is to compare both computed tomographic scan (CT) and color flow duplex ultrasound scanning (CDU) as surveillance modalities for clinically significant endoleaks and to evaluate concordance in abdominal aortic aneurysm (AAA) diameter measurements in patients after endovascular aneurysm repair (EVAR) in a busy hospital vascular laboratory. METHODS: We conducted a retrospective review of all patients who underwent endovascular repair of abdominal aortic aneurysms between February 1996 and November 2002 and had same-day CT and CDU studies. Ninety-seven patients enrolled in phase II clinical studies of Ancure devices had long-term follow-up with both modalities. The other patients underwent simultaneous studies, usually only at the 1-month postoperative visit. Peripheral vascular studies were performed by two certified vascular technicians; all CT scans were reviewed by one vascular surgeon. CT was used as the standard against which the sensitivity, specificity, negative predictive value, and positive predictive value of CDU in endoleak detection was determined. Statistics were performed by using the paired t test; a P value <.05 was considered significant. Kappa statistic was used to assess the correlation between CDU and CT in identifying endoleaks. The correlation between CT and CDU in AAA size measurements as well as in serial size measurements was also determined. RESULTS: Four hundred ninety-five same-day CT and CDU examinations were reviewed in 281 patients. Patients had an average follow-up of 34.6 months (range, 1 to 72 months). Thirty-five leaks were identified among the patients studied (12.4% overall). In comparison with CT, diagnosis of endoleak with ultrasound scanning was associated with a sensitivity of 42.9%, specificity of 96.0%, positive predictive value of 53.9%, and negative predictive value of 93.9%. The correlation between the two modalities was modest (kappa statistic 0.427). The minor axis transverse diameter as measured by ultrasound and CT scans (4.81 +/- 1.1 cm on CT and 4.55 +/- 1.1 cm on ultrasound) correlated closely (r =.93, P <.001.) Seventy percent of paired studies differed by < or =5 mm. Changes in aneurysm size throughout follow-up were -.29 +/-.71 cm on CT scan -.34 +/-.57 cm on duplex ultrasound scan. The correlation coefficient was.65 (P <.001). There was no significant difference in the change as measured by either modality on the paired t test. CONCLUSIONS: Although CDU demonstrates a high degree of correlation with CT scan in determining aneurysm size change over time, it has a low sensitivity and positive predictive value in endoleak detection. In the hospital vascular laboratory at a large tertiary care center, CDU cannot effectively replace CT scan in surveillance after EVAR.     

Lessons learned about prevalence and growth rates of abdominal aortic aneurysms from a 25‐year ultrasound population screening programme

Background

This study aimed to assess how the prevalence and growth rates of small and medium abdominal aortic aneurysms (AAAs) (3·0–5·4 cm) have changed over time in men aged 65 years, and to evaluate long‐term outcomes in men whose aortic diameter is 2·6–2·9 cm (subaneurysmal), and below the standard threshold for most surveillance programmes.

Methods

The Gloucestershire Aneurysm Screening Programme (GASP) started in 1990. Men aged 65 years with an aortic diameter of 2·6–5·4 cm, measured by ultrasonography using the inner to inner wall method, were included in surveillance. Aortic diameter growth rates were estimated separately for men who initially had a subaneurysmal aorta, and those who had a small or medium AAA, using mixed‐effects models.

Results

Since 1990, 81 150 men had ultrasound screening for AAA (uptake 80·7 per cent), of whom 2795 had an aortic diameter of 2·6–5·4 cm. The prevalence of screen‐detected AAA of 3·0 cm or larger decreased from 5·0 per cent in 1991 to 1·3 per cent in 2015. There was no evidence of a change in AAA growth rates during this time. Of men who initially had a subaneurysmal aorta, 57·6 (95 per cent c.i. 54·4 to 60·7) per cent were estimated to develop an AAA of 3·0 cm or larger within 5 years of the initial scan, and 28·0 (24·2 to 31·8) per cent to develop a large AAA (at least 5·5 cm) within 15 years.

Conclusion

The prevalence of screen‐detected small and medium AAAs has decreased over the past 25 years, but growth rates have remained similar. Men with a subaneurysmal aorta at age 65 years have a substantial risk of developing a large AAA by the age of 80 years.     

Ist das Screening auf abdominelle Aortenaneurysmen in Deutschland m?glich?

Introduction

Despite better clinical and surgical treatment options for abdominal aortic aneurysms (AAA) mortality rates are still increasing in Germany. The high rates are substantially due to spontaneous ruptures which in most cases prove fatal. International studies recommend screening programmes for AAA as these lead to a significant decrease in aneurysm-dependent mortality. However, in Germany such programmes are still lacking. The general possibility of ultrasound screening by family doctors was evaluated using a questionnaire.

Methods

A written survey of 2,000 representative family practitioners in Germany was initiated to determine the availability of ultrasound devices, knowledge relating to screening procedures and motivation to perform screening. The representativeness of the results was measured by a telephone re-test.

Results

The survey revealed that all of the approximately 60,000 family doctors in Germany are able to participate in an ultrasound screening program. More than two thirds of them possess an ultrasound machine and are trained to perform ultrasound screening. Most family doctors are motivated to take part in training courses and 75% would participate in a nationwide screening program.

Conclusions

A nationwide AAA screening in Germany is basically possible as participants are within easy reach of a family doctor with screening facilities in all areas of Germany. However, in order to do this it will be necessary to design a target group-oriented introduction campaign and a suitable financial remuneration structure must be established.     

Carotid Atherosclerosis and Relation to Growth of Infrarenal Aortic Diameter and Follow-up Diameter: The Tromsø Study

ObjectivesThis research aims to study how carotid atherosclerosis is related to growth of infrarenal aortic diameter and aneurysmal formation.DesignPopulation-based follow-up study.Materials and methodsAt baseline, ultrasound examination of the carotid artery and the abdominal aorta was performed in 4241 persons from a general population with no evidence of abdominal aortic aneurysm (AAA). The burden of atherosclerosis was assessed as carotid total plaque area (TPA). After a mean follow-up of 6.3 years, a new ultrasound examination was performed and measurements of the aortic diameter and carotid TPA were repeated. The effects on aortic diameter progression, follow-up diameter and risk for AAA were assessed in multiple linear and logistic regression models according to carotid TPA, adjusted for known risk factors.ResultsWhen analysing AAA as a dichotomous variable, a borderline association between atherosclerosis and AAA could be demonstrated. When modelling aortic diameter as a continuous variable, a 1-SD increase in 5 years' carotid plaque area (ΔTPA) was associated with a 0.12-mm growth in infrarenal aortic diameter (standard error (SE) 0.04) and a 0.20-mm wider aorta at follow-up (SE 0.06). No independent relation was seen for baseline atherosclerosis.ConclusionsCarotid plaque progression was positively related to growth in infrarenal aortic diameter and aortic diameter at follow-up. Whether this co-variation between plaque growth and aortic diameter growth is causally related or independent events is still an open question.     

Variability in measurement of abdominal aortic aneurysms

Purpose: The purpose of this study was to report interobserver and intraobserver variability of computed tomography (CT) measurements of abdominal aortic aneurysm (AAA) diameter and agreement between CT and ultrasonography observed in the course of a large, multicenter, randomized trial on the management of small AAAs.Methods: CT measurements of AAA diameter from participating centers were compared with measurements made from the same scan by a central laboratory. Blinded central remeasurement of a randomly selected subset of these CT scans was used to assess intraobserver variability. Agreement between AAA measurements by CT and ultrasonography done within 30 days of each other was also assessed.Results: For interobserver pairs of local and central CT measurements of AAA diameter (n = 806), the difference was 0.2 cm or less in 65% of pairs, but 17% differed by at least 0.5 cm. For intraobserver pairs of central CT remeasurements (n = 70), 90% differed by 0.2 cm or less, 70% were within 0.1 cm, and only one differed by 0.5 cm. Of 258 ultrasound-measured and central CT pairs, the difference was 0.2 cm or less in 44% and at least 0.5 cm in 33%. Ultrasound measurements were smaller than central CT measurements by an average of 0.27 cm (p < 0.0001). Local CT and ultrasound measurements showed a marked preference for recording by half centimeter.Conclusions: A high degree of precision is possible in CT measurement of AAA diameter, but this precision may not be obtained in practice because of differences in measurement techniques. Differences between imaging modalities increase variability further. Variations in AAA measurement of 0.5 cm or more are not uncommon, and this should be taken into account in management decisions. Efforts to reduce variation in measurement are warranted and might include (1) seeking agreement between surgeons and radiologists on a precise definition of AAA diameter, (2) limiting the number of radiologists who measure AAAs, and (3) use of calipers and magnifying glass for CT measurements. (J VASC SURG 1995;21:945-52.)     

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.     

Ultraschallscreening auf abdominale Aortenaneurysmen (AAA)

Background

Abdominal aortic aneurysm (AAA) rupture is associated with a high mortality. The only preventive therapy is early diagnosis and elective surgery of rupture prone AAAs. Using B-mode sonography AAAs can be detected early with great reliability. Thus, a population-based ultrasound screening might lower the risk of abdominal aortic aneurysm ruptures.

Materials and methods

A literature analysis (until June 2014) was performed in the databases of MEDLINE, PubMed, and SCOPUS including all randomized controlled trials (RCT), systematic reviews, meta-analyses, health technology assessments (HTA reports) and medical guidelines on AAA screening. The following keywords were used: abdominal aortic aneurysm, ultrasound screening, evidence, guidelines. Clinically relevant endpoints were the following: AAA-associated mortality, overall mortality, number of elective AAA operations, number of ruptured AAAs and emergency surgery for different follow-up intervals.

Results

In four RCTs men between 65 and 83 years either had a single or no ultrasound examination of the abdominal aorta. Older women were only analyzed in one RCT. The meta-analysis of the RCT results shows that ultrasound screening caused a significant decrease of AAA-associated mortality, number of ruptured abdominal aneurysms, and number of emergency operations, whereas the number of elective surgeries significantly increased. Overall mortality was only moderately decreased by AAA screening.

Conclusion

Evidence was provided in population-based RCTs and meta-analyses for the efficiency of ultrasound based AAA screening for men older than 65 years. Presently the Federal Joint Committee (G-BA) and the Institute for Quality and Efficiency in Health Care (IQWIG) are evaluating a national ultrasound-based AAA screening program for Germany. However, additional clinical trials are necessary to assess risk groups especially men under 65 years, women with nicotine abuse and cardiovascular diseases which were underrepresented in previous studies.     

High plasma microfibrillar-associated protein 4 is associated with reduced surgical repair in abdominal aortic aneurysms

ObjectiveIdentifying biomarkers for abdominal aortic aneurysms (AAA) could prove beneficial in prognosis of AAA and thus the selection for treatment. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein that is highly expressed in aorta. MFAP4 is involved in several tissue remodeling-related diseases. We aimed to investigate the potential role of plasma MFAP4 (pMFAP4) as a biomarker of AAA.MethodsPlasma samples and data were obtained for 504 male AAA patients and 188 controls in the Viborg Vascular (VIVA) screening trial. The pMFAP4 levels were measured by Alphalisa. The Mann-Whitney U test assessed differences in pMFAP4 levels between the presence and absence of different exposures of interest. The correlation between pMFAP4 and aorta growth rate were investigated through spearman's correlation analysis. Immunohistochemistry and multiple logistic regression adjusted for potential confounders assessed the association between pMFAP4 and AAA. Multiple linear regression assessed the correlation between pMFAP4 and aorta growth rate. Cox regression and competing risk regression were used to investigate the correlation between AAA patients with upper tertile pMFAP4 and the risk of undergoing later surgical repair.ResultsA significant negative correlation between pMFAP4 and aorta growth rate was observed using spearman's correlation analysis (ρ = −0.14; P = .0074). However, this finding did not reach significance when applying multiple linear regression. A tendency of decreased pMFAP4 was observed in AAA using immunohistochemistry. Competing risk regression adjusted for potential confounders indicated that patients with upper tertile pMFAP4 had a hazard ratio of 0.51 (P = .001) for risk of undergoing later surgical repair.ConclusionsHigh levels of pMFAP4 are associated with a decreased likelihood of receiving surgical repair in AAA. This observation warrants confirmation in an independent cohort.     

Ultrasound surveillance of endovascular aneurysm repair: a safe modality versus computed tomography

Routine ultrasound surveillance is adequate and safe for monitoring endovascular aneurysm repairs (EVARs). A retrospective chart review including 160 endograft patients was performed from August 2000 to September 2005. All ultrasound examinations (n = 359) were performed by a board-certified vascular surgery group's accredited laboratory. Registered vascular technologists utilized the same equipment consisting of Siemens Antares high-definition ultrasonography with tissue harmonics and color flow Doppler. An identical protocol was followed by each technologist: scan body and both limbs of the endograft and distal iliac vessels, measure anterior-posterior aneurysm sac size, and detect intrasac pulsatility and color flow. Statistical analysis utilized Pearson's correlation coefficient and the paired t-test. Forty-one endoleaks were discovered out of the 359 exams (11.4%). There were type I (7, 17%), type II (26, 63%), and combined type I with type II (8, 20%) endoleaks. Correlation with computed tomography (CT) was obtained in 35 of these cases. CT discovered three endoleaks that were not seen with ultrasound. However, these particular ultrasound exams were inadequate due to additional factors (bowel gas, body habitus, hernia), which prompted CT investigation and, hence, endoleak discovery. Of the 41 endoleaks found on ultrasound, only 14 were seen on CT. Specifically, 26 type II endoleaks were seen with ultrasound versus only nine during CT. Additional factors addressed included comparison between ultrasound and CT of residual aneurysm sac measurements and conditions limiting ultrasound examination. Although criticized in the past, color flow ultrasonography is a safe and effective modality for surveillance of aortic endografts. Utilizing ultrasound to analyze abdominal aortic aneurysm (AAA) sac dimensions and endoleak detection is statistically sound for screening AAA status post-EVAR.     

Ultraschalldiagnostik der abdominellen Aorta

Background and objectives

The ideal method for screening investigations is one which is as free as possible from side effects, is easily learnt and can therefore be broadly employed to recognize abdominal aortic aneurysms (AAA) with a high degree of certainty. Although ultrasonography fulfils these criteria, the measurement method is not standardized. Different measurement methods are used in ultrasonography as well as in computed tomography (CT) studies and the measurement method is actually described sufficiently in only 57?% of cases.

Methods

This article gives a critical review of the current literature on measurement methods and the validity of ultrasonography for determination of the diameter of the aorta, particularly for AAAs and presents the measurement principles for making measurements as precisely as possible.

Results and conclusion

The most precise determination of the diameter is carried out by electrocardiogram (ECG) gating according to the leading edge method with orthogonal slicing. Within the framework of screening investigations, sufficient measurement precision can be achieved by adherence to orthogonal slicing. In these standardized measurement methods ultrasonography shows valid and reproducible results even in comparison to CT and is the method of choice in screening investigations for AAAs.     

超声造影诊断乳腺占位性病变影响因素

目的 分析超声造影（CEUS）诊断乳腺占位性病变出现假阳性、假阴性结果的影响因素。方法 回顾性分析349例接受常规超声（US）、CEUS及乳腺X线摄影（MG）的女性乳腺单发占位性病变患者,以病理结果为金标准,将CEUS诊断结果分为真阳性、真阴性、假阳性和假阴性。采用单因素及多因素Logistic回归分析筛选CEUS出现假阳性、假阴性结果的影响因素。结果 349个乳腺病变中,良性病变205个,恶性病变144个。CEUS正确诊断127个恶性、170个良性病变,诊断敏感度为88.19%（127/144）,特异度82.93%（170/205）,准确率85.10%（297/349）,假阳性率17.07%（35/205）,假阴性率11.81%（17/144）。单因素及多因素Logistic回归分析结果显示,年龄、病变至乳头距离（DtP）、合并高危病变是CEUS假阳性的影响因素（P均<0.05）;而年龄、病灶最大径（LMD）与CEUS假阴性有关（P均<0.05）。结论 乳腺占位性病变患者年龄、DtP、是否合并高危病变与CEUS假阳性有关;年龄、病灶最大径与CEUS假阴性有关。     

Duplex ultrasound scanning versus computed tomographic angiography for postoperative evaluation of endovascular abdominal aortic aneurysm repair

Objective: The purpose of this study was to compare duplex ultrasound scanning and computed tomographic (CT) angiography for postoperative imaging and surveillance after endovascular repair of abdominal aortic aneurysm (AAA). Methods: One hundred consecutive patients with AAA underwent endovascular (Medtronic AneuRx, stent graft) aneurysm repair and were imaged with both CT angiography and duplex ultrasound scanning at regular intervals after the procedure. Each imaging modality was evaluated for technical adequacy and for documentation of aneurysm size, endoleak, and graft patency. In concurrent scan pairs, accuracy of duplex scanning was compared with CT. Results: A total of 268 CT scans and 214 duplex scans were obtained at intervals of 1 to 30 months after endovascular aneurysm repair (mean follow-up interval, 9 ± 7 months). All CT scans were technically adequate, and 198 (93%) of 214 duplex scans were technically adequate for the determination of aneurysm size, presence of endoleak, and graft patency. Concurrent (within 7 days of each other) scan pairs were obtained in 166 instances in 76 patients (1-6 per patient). The maximal transverse aneurysm sac diameter measured with both methods correlated closely (r = 0.93; P < .001) without a significant difference on paired analysis. In 92% of scans, measurements were within 5 mm of each other. Diagnosis of endoleak on both examinations correlated closely (P < .001), and compared with CT, duplex scanning had a sensitivity of 81%, a specificity of 95%, a positive predictive value of 94%, and a negative predictive value of 90%. Discordant results occurred in 8% of examinations, and in none of these was the endoleak close to the attachment sites or associated with aneurysm expansion. An endoleak was demonstrated on both tests in all eight patients who had an endoleak judged severe enough to warrant arteriography. Graft patency was documented in each instance, without discrepancy, with both modalities. Conclusions: High-quality duplex ultrasound scanning is comparable to CT angiography for the assessment of aneurysm size, endoleak, and graft patency after endovascular exclusion of AAA. (J Vasc Surg 2000;32:1142-8.)     

Early ultrasound in acute appendicitis avoids CT in most patients but delays surgery and increases complicated appendicitis if nondiagnostic – A retrospective study

BackgroundWe determined whether increasing early imaging (in the emergency department) was associated with earlier surgery and a decrease in complicated appendicitis.MethodsRetrospective study; 3013 operations between 12/2006–12/2016.ResultsEarly imaging increased from 13.1% to 74.1%, mostly due to increasing use of ultrasound. Negative appendectomies decreased from 10.7% to 5.1% (p < 0.001). Ultrasound was diagnostic in 80.5%. The false positive rate of ultrasound was 4%. Median time to surgery following positive ultrasound was 7.4 h (IQR 5.8–9.4), shorter compared to no early imaging (13.3 h, IQR 7.2–20.0; p < 0.001). However, median time to surgery following inconclusive and negative ultrasound was 11.5 h (IQR 8.7–16.1) and 17.0 h (IQR 10.3–26.7) respectively. The incidence of complicated appendicitis was 40% and 37.7%, higher than 21.5% in patients with positive US (p < 0.001).ConclusionsEarly imaging resulted in earlier surgery but did not reduce the incidence of complicated appendicitis. Ultrasound averted the need for CT in the majority of patients. When ultrasound was negative or inconclusive, time to surgery was delayed and the rate of complicated appendicitis higher.