Biomedical subjects

D M DeLong

Publications and source records attributed to D M DeLong.

At least 37 records · Page 2Linked to original sources

PubMed1999

Sonographically guided compression repair of pseudoaneurysms: further experience from a single institution.

OBJECTIVE: Our purpose was to perform a comprehensive review of our experience with compression of postcatheterization groin pseudoaneurysms. MATERIALS AND METHODS: Two hundred eighty-one patients underwent 306 sonographically guided compression procedures on 297 groin pseudoaneurysms after femoral artery catheterization. The medical records, cardiac catheterization reports, and sonographic images were reviewed to determine patient demographics, type of catheterization procedure performed, sheath size, access site, interval from sheath removal to compression, anticoagulation status, pseudoaneurysm dimensions, complications, and follow-up information. Statistical analysis was performed using Pearson's chi-square and Kendall tau tests. RESULTS: The success rate for the initial compression attempt was 72.1%. Of the 83 failed compression attempts, 12 patients underwent a second attempt, of which seven attempts were successful. Therefore, counting both first and second attempts, the success rate was 74.4%. A strong negative correlation existed between anticoagulation status and success, with a 70% failure rate in patients with anticoagulated blood. Smaller pseudoaneurysm size was strongly correlated with success. Of the 83 failed cases, 49 ultimately underwent surgical repair. Eleven complications (3.6%) occurred, including three patients with rupture during compression. No deaths occurred as a result of compression repair. CONCLUSION: We conclude that sonographically guided pseudoaneurysm compression repair is an effective alternative to surgical repair, though nearly one third of compression attempts will fail and most of those patients will ultimately require surgery. The procedure is less effective when the patient's blood is anticoagulated and when the pseudoaneurysm is large. The procedure carries an overall complication rate of 3.6% and a risk for rupture of 1%.

Aged↗

PubMed1998

Carcinoid metastases to the liver: role of triple-phase helical CT.

PURPOSE: To evaluate triple-phase helical computed tomography (CT) of carcinoid liver metastases. MATERIALS AND METHODS: Triple-phase helical CT was performed in 31 patients with proved carcinoid liver metastases. Hepatic arterial-dominant phase (HAP) and portal venous-dominant phase (PVP) images were obtained 20 and 70 seconds after intravenous iopamidol injection. Four independent readers reviewed each phase for lesion number, conspicuity, and attenuation relative to liver. Three readers reviewed each phase to determine which phase best showed the lesions. RESULTS: The lesions detected by readers 1-4 were as follows: noncontrast phase, 164, 177, 204, and 229 lesions; HAP, 178, 177, 214, and 238 lesions; and PVP, 180, 189, 215, and 250 lesions (P > .05). On HAP images, readers found that 80, 73, 96, and 102 lesions were hyperattenuating. Consensus indicated there were 206 focal lesions. Of these 206 lesions, 72, 72, and 62 lesions were best seen on the noncontrast phase, HAP, and PVP images, respectively. Six, 28, and six lesions were seen only on the noncontrast phase, HAP, and PVP images, respectively. Two patients had lesions seen only on the HAP images. CONCLUSION: The HAP and, to a lesser extent, the noncontrast phase provide added value in evaluating carcinoid liver metastasis.

Carcinoid Tumor↗

PubMed1998

Dynamic helical CT of the abdomen: prospective comparison of pre- and postprandial contrast enhancement.

PURPOSE: To investigate effects of a liquid meal on contrast material enhancement at dynamic helical computed tomography (CT). MATERIALS AND METHODS: Twenty healthy, fasting subjects underwent intravenous injection of nonionic contrast material at 4 mL/sec. Axial CT sections were obtained at a single level 15 seconds after injection, then every 5 seconds for 2 minutes. This protocol was repeated 1 week later, after ingestion of a 360-calorie liquid meal. Hepatic, splenic, and aortic attenuation were measured before and after contrast material administration. Peak enhancement level, time to peak enhancement, slope of hepatic enhancement, and hepatic, splenic, and aortic enhancement ratios were determined. RESULTS: Postprandial time to peak enhancement was 4.4 seconds earlier than preprandial (59.6 seconds +/- 9.0 [1 standard deviation] vs 64.0 seconds +/- 9.5; P < .02). No differences in maximum attenuation were found (P > .27). Postprandial maximum slope of hepatic enhancement and temporal and quantitative enhancement characteristics in aorta and spleen did not significantly differ. Postprandial hepatic-to-splenic enhancement ratios increased (P = .04), and aortic-to-hepatic ratios decreased (P = .01). Aortic-to-splenic ratios did not differ (P = .45). CONCLUSION: A liquid meal before intravenous injection of contrast material produces more rapid peak hepatic enhancement, with slightly increased relative hepatic enhancement. A patient's dietary status, however, should not influence the CT protocol.

Adult↗

PubMed1998

Abdominal percutaneous interventional procedures: comparison of CT and US guidance.

PURPOSE: To compare ultrasound (US) with computed tomography (CT) as a guidance modality for percutaneous interventional procedures. MATERIALS AND METHODS: A database of abdominal interventional procedures was reviewed for the 6 months preceding and 6 months after the opening of a dedicated US interventional suite. Changes in the number and type of procedures performed, room time, number of needle passes, and complication rates were calculated. RESULTS: In the first 6 months, 305 interventional procedures (138 tissue biopsies and 167 fluid aspirations) were performed (CT guidance in 87% [n = 120] and 95% [n = 159], respectively). In the 6 months after installation of the suite, 395 procedures (195 tissue biopsies and 200 fluid aspirations) were performed (US guidance in 76% [n = 148] and 34% [n = 67], respectively). The largest increase in US utilization was for guidance of tissue biopsies, rising from 6% (18 of 305) to 37% (148 of 395) of all procedures. Room time was significantly less for US-guided procedures (mean US room time, 77 minutes +/- 33 [1 standard deviation]; mean CT room time, 99 minutes +/- 38; P < .0001). CONCLUSION: US guidance often allows performance of quicker, more accurate procedures than does CT guidance, probably because of its real-time capabilities.

Abdomen↗

PubMed1998

Doppler sonography of the portal vein and hepatic artery: measurement of a prandial effect in healthy subjects.

PURPOSE: To determine if the prandial effect outweighs variability in the measurement of portal venous blood flow and hepatic arterial resistive index. MATERIALS AND METHODS: Fourteen healthy adult volunteers fasted overnight. For eight of the subjects, two sonographers performed three determinations of portal venous blood flow and hepatic arterial resistive index before and 30 minutes after a liquid meal (5 mg per kilogram of body weight). In the remaining six volunteers, determinations were made at the same time intervals but without a meal. The sonographers were blinded to on-screen measurements and the subject's prandial status. RESULTS: For subjects examined after the meal by sonographers A and B, respectively, portal venous blood flow increased from 144.2 to 201.7 mL/min and from 209.2 to 331.9 mL/min and hepatic arterial resistive index increased from 0.70 to 0.77 and from 0.67 to 0.78. After repeated-measures analysis of variance, ingestion of a meal was estimated to increase portal venous blood flow by 96.3 mL/min (P < .001)--a change in sonographers could affect the measurement by 76.7 mL/min (P < .001)--and to increase hepatic arterial resistive index by 0.089 (P < .001)--a change in sonographers did not affect the measurement (P > .1). CONCLUSION: The prandial effect on portal venous blood flow is only marginally greater than the interobserver variation in the measurement. Hepatic arterial resistive index also increases after a meal, but interobserver differences between sonographers are minimal; therefore, it is a more robust measurement.

Adult↗

PubMed1998

Helical liver CT with computer-assisted bolus-tracking technology: is it possible to predict which patients will not achieve a threshold of enhancement?

PURPOSE: To determine how often a prescribed threshold of hepatic contrast material enhancement is not reached at helical computed tomography (CT) of the liver in patients in a tertiary teaching hospital-based practice and which variables are predictive of failure. MATERIALS AND METHODS: Hepatic helical CT was performed in 250 consecutive patients with computer-assisted bolus-tracking technology after either mechanical injection at 3 mL/sec (n = 177) or manual injection (n = 73) of 150 mL of iopamidol. Demographic variables were recorded. After 17 seconds, low-milliamperage monitoring scans were obtained every 6 seconds until hepatic enhancement of 50 HU over baseline was achieved. Time-enhancement curves were reviewed. RESULTS: The threshold was not reached by 60 seconds in 88 patients (35%; default group). The success and default groups were similar in most variables and differed only in weight (P = .002), patient status (inpatient, outpatient, or emergency department; P < .001), and injection type (mechanical vs manual; P < .001). Ten patients (4%) did not achieve the threshold because of inappropriate placement of elliptic regions of interest. CONCLUSION: By using computer-assisted bolus-tracking technology, 35% of patients in a tertiary teaching hospital-based practice will not achieve a threshold of 50 HU above baseline by 60 seconds after injection initiation and will require the use of a set delay. Failures are more frequent in patients who are heavy and in inpatients. No historic or demographic factors are strongly predictive of failure.

Adult↗

PubMed1998

Diagnosis of pancreatic carcinoma: role of FDG PET.

OBJECTIVE: The purpose of this study was to investigate the role of positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in differentiating benign from malignant disease in patients with possible pancreatic malignancy. SUBJECTS AND METHODS: All patients with a possible diagnosis of pancreatic carcinoma based on CT or ERCP findings were eligible for inclusion in this prospective study. PET imaging of the abdomen was performed in 37 patients and was interpreted as positive if FDG activity in the pancreas exceeded background activity and as negative if activity was less than or equal to background activity. Semiquantitative analysis was performed by calculating a standardized uptake ratio. Studies were reviewed independently by two radiologists, and results were correlated with biopsy results and with CT and ERCP findings. Sensitivity and specificity of FDG PET for revealing pancreatic malignancy was determined. RESULTS: FDG activity in the pancreas was increased in 24 patients, and adenocarcinoma was diagnosed in 22 of these patients (92%). Two patients (8%) with increased activity had benign disease, including one patient with chronic pancreatitis who showed no evidence of tumor at laparotomy and one patient with a mucinous cystic tumor who showed no malignant features at laparotomy. FDG uptake was low or normal in 13 patients, 10 of whom (77%) had benign disease. FDG uptake was also low in three patients with adenocarcinoma, whose tumor size ranged from 2 to 4 cm in diameter. The mean standardized uptake ratio value for malignant disease was 5.1 (range, 1.0-10.1) and for benign disease was 1.9 (range, 0.0-5.8) (p < .001). The sensitivity of FDG PET for revealing malignant disease in the pancreas was 88% and the specificity was 83%. CONCLUSION: FDG PET is a sensitive and specific noninvasive technique for the diagnosis of pancreatic malignancy.

Adenocarcinoma↗

PubMed1997

Comparing risk-adjustment methods for provider profiling.

Risk-adjustment and provider profiling have become common terms as the medical profession attempts to measure quality and assess value in health care. One of the areas of care most thoroughly developed in this regard is quality assessment for coronary artery bypass grafting (CABG). Because in-hospital mortality following CABG has been studied extensively, risk-adjustment mechanisms are already being used in this area for provider profiling. This study compares eight different risk-adjustment methods as applied to a CABG surgery population of 28 providers. Five of the methods use an external risk-adjustment algorithm developed in an independent population, while the other three rely on an internally developed logistic model. The purposes of this study are to: (i) create a common metric by which to display the results of these various risk-adjustment methodologies with regard to dichotomous outcomes such as in-hospital mortality, and (ii) to compare how these risk-adjustment methods quantify the 'outlier' standing of providers. Section 2 describes the data, the external and internal risk-adjustment algorithms, and eight approaches to provider profiling. Section 3 then demonstrates the results of applying these methods on a data set specifically collected for quality improvement.

Aged↗

PubMed1997

Doppler US measurement of portal venous flow: variability in healthy fasting volunteers.

PURPOSE: To describe the intrinsic sampling variability of measurements of portal venous flow in healthy volunteers and to estimate the variability attributable to the sonographer, the subject, and the measurement. MATERIALS AND METHODS: In a randomized controlled fashion, nine sonographers measured portal venous flow in five subjects. Each sonographer measured portal venous flow in each volunteer during three separate sessions with three measurements per session. Analysis of variance was used to estimate the contribution of several factors to the observed variability. RESULTS: Overall mean portal venous flow was 390 mL/min +/- 234 (range, 18-1,511 mL/min). The estimated variance components were 1.1 (3%), 2.5 (7%), 7.2 (21%), and 24.0 (69%) for the subject, the sonographer, the interaction between subject and sonographer, and the measurement or intrinsic variability. Similar results were obtained when the analysis of variance was fit by using the rank and median of the measurements. CONCLUSION: Substantial variability exists in measurement of portal venous flow. Variability attributed to inherent differences in repeat measurements contributes more to overall variability than that attributed to either sonographers or subjects.

Adult↗

PubMed1997

Third ventricle: size and appearance in normal fetuses through gestation.

PURPOSE: To define the size and appearance of the normal fetal third ventricle. MATERIALS AND METHODS: The third ventricle was prospectively assessed in 441 consecutive normal second- and third-trimester fetuses. The fetuses were divided into six gestational age ranges. Data regarding the size and configuration of the third ventricle were analyzed for each group. RESULTS: The third ventricle was seen in 435 of 440 (98.9%) fetuses. It appeared as a single echogenic line between the thalami in 171 (38.9%) fetuses, as parallel echogenic lines outlining a fluid-filled lumen in 243 (55.2%) fetuses, and as divergent lines delineating a V-shaped fluid-filled structure in 21 (4.8%) fetuses. The single-line configuration was most common early in the second trimester. Later in pregnancy, the ventricle walls could be discerned as separate parallel or divergent lines outlining a fluid-filled lumen. The average width of the ventricle was relatively constant at approximately 1 mm from 12 to 28 weeks. After this time, it enlarged, reaching a maximum 1.9 mm. CONCLUSION: The third ventricle can be imaged in most second- and third-trimester fetuses. Its size and configuration evolve through the second and third trimesters. This evolution must be considered in the evaluation of normality. At any gestational age, a third ventricle greater than 3.5 mm in width should be viewed with concern for abnormality.

Abnormalities, Multiple↗

PubMed1997

Early systole in the healthy kidney: variability of Doppler US waveform parameters.

PURPOSE: To determine the sampling variability of intrarenal Doppler ultrasound (US) indexes of early systole in a screened population of healthy individuals. MATERIALS AND METHODS: Doppler US measurements were obtained in the superior, middle, and inferior regions of 132 kidneys in 66 healthy, potential kidney donors. All individuals subsequently underwent angiography. Systematic measurement differences and random effects were estimated for sampling from a particular parenchymal region, from a kidney in a subject, from an individual in a population, and from a vascular territory. RESULTS: Coefficients of variations ranged from 20% to 30%. Most (55%-66%) of the observed variation was attributable to random differences between repeated measurements in the same kidney. No systematic variations attributable to kidney region, vascular territory, right versus left kidney, or subject age were found for acceleration time, acceleration, or waveform shape. Some evidence of fixed variation between kidneys and between regions was found for peak systolic velocity, but the magnitude of this variation was small. Averages of repeated measurements may decrease the probability of exceeding the normal threshold for acceleration but not for acceleration time. CONCLUSION: Measurements of Doppler parameters of the early systole have substantial intrinsic variability. Thus, caution is needed when interpreting small changes in these measurements within a kidney or between individuals.

Adult↗

PubMed1997

Axillary lymph nodes: mammographic, pathologic, and clinical correlation.

OBJECTIVE: The purpose of this study was to determine the cause and frequency of axillary abnormalities seen mammographically and to evaluate the imaging characteristics of lymphadenopathy that are associated with malignancy. MATERIALS AND METHODS: Ninety-six axillary abnormalities seen mammographically in 94 patients were retrospectively reviewed and correlated with the clinical diagnoses and pathologic results found in the medical records. For each abnormality, the length, margins, and presence of microcalcifications were noted. Logistic regression was used to determine an association between these findings and status (benign or malignant). RESULTS: Seventy-six of 94 patients had lymphadenopathy. Eighteen of 94 patients had an abnormality other than lymphadenopathy. Because two of these 94 patients had more than one abnormality, a total of 96 abnormalities occurred, 20 of which were due to an abnormality other than lymphadenopathy. Regarding the 76 cases of lymphadenopathy, the most frequent diagnosis was nonspecific benign lymphadenopathy in 29% (n = 22) of cases, followed by metastatic breast cancer in 26% (n = 20) and chronic lymphocytic leukemia or well-differentiated lymphocytic lymphoma in 17% (n = 13). Other causes (n = 21) included collagen vascular disease, lymphomas other than well-differentiated lymphocytic lymphoma, metastatic disease from nonbreast primary site, metastatic disease from unknown primary site, sarcoidosis. HIV-related lymphadenopathy, and reactive lymphadenopathy associated with a breast abscess. An association between length of nonfatty lymph nodes and malignant status was statistically significant at the .001 level. When a length greater than 33 mm was used as a predictor of malignancy, the specificity and sensitivity were 97% and 31%, respectively. We found an association between malignancy and nonfatty lymph nodes with ill-defined or spiculated margins (p = .053). Regarding the 20 abnormalities other than lymphadenopathy, epidermal cysts (n = 7) were most prevalent. CONCLUSION: The most common axillary abnormality revealed on mammography was abnormal lymph nodes. Homogeneously dense (nonfatty) axillary lymph nodes were strongly associated with malignancy when the lymph nodes were longer than 33 mm, had ill-defined or spiculated margins, or contained intranodal microcalcifications. However, our study confirmed that in most cases benign and malignant lymph nodes cannot be distinguished from each other mammographically.

Aged↗

PubMed1997

Sonographic assessment of lower limb vein diameters: implications for the diagnosis and characterization of deep venous thrombosis.

OBJECTIVE: The goals of this study were to define the normal range of diameters in the deep veins of the thigh and to compare this range with diameters of veins with acute thrombus and of veins with chronic changes from prior deep venous thrombosis (DVT). SUBJECTS AND METHODS: The anteroposterior diameter of the vein and adjacent artery was measured at five predefined levels in 975 legs of patients referred for sonographic examination for suspected DVT. The mean vein diameter and mean vein-to-artery ratio were calculated for normal veins, vein segments with acute DVT, and vein segments with chronic changes from prior DVT. RESULTS: The diameter of normal deep leg veins was largest at the level of the common femoral vein (mean diameter, 10.5 mm). The diameter progressively decreased until the mid superficial femoral vein and remained relatively constant (mean diameter, 6.4-6.8 mm) more caudally. Similarly, vein-to-artery ratios progressed from a mean ratio of 1.3 in the common femoral vein to 1.2 at other levels. We found no significant differences in vein diameter between the right and the left legs. Vein segments with acute thrombus were larger than corresponding segments of normal veins. However, we found considerable overlap in the ranges of diameter of veins with and without acute DVT. At corresponding levels, veins with chronic DVT tended to be narrower than normal veins; however, the differences were small, and this diameter range also substantially overlaps that of normal veins. CONCLUSION: When grouped, veins with acute DVT were larger than normal veins. Likewise, veins with chronic DVT were smaller than normal veins. Because we found that the ranges of diameters of veins overlapped for different groups of veins, size alone is unlikely to provide compelling evidence for the diagnosis of acute versus chronic DVT, except at extreme diameters. Diameters of veins as revealed by sonography should be interpreted in the context of other sonographic findings.

Female↗

PubMed1996

Renal resistive indexes: variability in Doppler US measurement in a healthy population.

PURPOSE: To determine the variability in resistive index (RI) in normal kidneys, possible causes of variability, and consequences of reporting a single value. MATERIALS AND METHODS: Doppler ultrasound RI measurements were obtained in the upper, middle, and lower regions of 118 kidneys in 58 healthy subjects (aged 24-70 years; 35 women, 23 men) who subsequently underwent angiography. The effects of sampling a particular parenchymal region, vascular territory, or kidney were assessed. RESULTS: Kidney region, vascular territory, and right versus left kidney had no consistently significant effect (P < or = .05) on RI. Age had a statistically significant effect. RI readings were highly correlated with each other both within a subject and within a kidney. The probability that a single RI value would exceed 0.70 in a healthy 45-year-old subject was 6%; this decreased to 3% when three readings were averaged. CONCLUSION: The variability of RI measurements in a kidney suggests that a number of RI readings should be averaged before a single representative value is reported.

Adult↗

PubMed1996

Can the US examination for lower extremity deep venous thrombosis be abbreviated? A prospective study of 755 examinations.

PURPOSE: To determine if the ultrasound (US) survey of the lower extremity for deep venous thrombosis (DVT) can be curtailed without compromising diagnostic efficacy. MATERIALS AND METHODS: The authors performed 755 US examinations in 721 patients (1,024 lower extremities) referred for suspicion of lower extremity DVT. The full lengths of the deep veins were studied, and findings were categorized at five locations: common femoral vein (CFV), proximal superficial femoral vein (CFV), mid-SFV, distal SFV, and popliteal vein (PV). RESULTS: Acute thrombus was seen in one or more veins in 131 (17.4%) of the 755 examinations. DVT isolated to a single vein was seen in 28 (21.4%) of the 131 positive examinations: DVT was limited to the CFV in eight studies (61%), to the SFV in six studies (4.6%), and to the PV in 14 studies (10.7%). CONCLUSIONS: DVT limited to a single vein occurs with sufficient frequency that the US screening survey cannot be abbreviated without loss of diagnostic efficacy.

Femoral Vein↗

PubMed1996

CT during arterial portography: comparison of injection into the splenic versus superior mesenteric artery.

PURPOSE: To determine whether the diagnostic quality of computed tomography (CT) during arterial portography (CTAP) performed via the splenic artery (SA) is better than that performed via the superior mesenteric artery (SMA). MATERIALS AND METHODS: The authors evaluated CTAP images obtained in 98 patients from 1991 to 1994; 47 examinations were performed via the SA and 51 were performed via the SMA. Images were reviewed, by consensus, by three radiologists blinded to catheter location. Hepatic enhancement was quantitatively assessed in 53 patients (31 in the SA group, 22 in the SMA group). RESULTS: The numbers of low-attenuation non-tumor-related perfusion defects (19 in the SA group, 17 in the SMA group), high-attenuation non-tumor-related perfusion defects (six in the SA group, six in the SMA group), diffuse mottled perfusion abnormalities (six in the SA group, five in the SMA group), and portal venous flow defects (20 in the SA group, 20 in the SMA group) were similar in both groups (P > .05). Peak hepatic enhancement was similar in both groups (SMA group = 111 HU; SA group = 112 HU) (P > .05). CONCLUSION: There is no difference in quality between CTAP performed via the SA versus CTAP performed via the SMA.

Adult↗

PubMed1996

Temporal artery tap: usefulness and limitations in carotid sonography.

PURPOSE: To examine the effectiveness of percussion of the superficial temporal artery for identification of the external carotid artery (ECA). MATERIALS AND METHODS: The temporal artery tap maneuver was performed on 324 carotid arteries (163 patients). Evidence for transmission of the effect of the temporal tap was sought in the pulsed Doppler ultrasound waveforms of the ECA, common carotid artery (CCA), and internal carotid artery (ICA). The location and severity of stenotic lesions were recorded. The relative amplitudes of the oscillations created by the tap were compared. RESULTS: The temporal tap effect could be seen in 262 ECAs (81%), 174 CCAs (54%), and 106 ICAs (33%). The tap effect can be seen in the ICA at all grades of ICA disease. When the oscillations were seen in only one of the two major branches, that branch was always the ECA. When the temporal tap effect was found in the ICA, the amplitudes of the oscillations were the same as or greater than those of the ECA in 26% of cases. CONCLUSION: Waveform oscillations from the temporal tap maneuver often can be found beyond the ECA in the CCA and ICA. Thus, the temporal tap alone may not reliably distinguish the ECA from the ICA or CCA.

Adolescent↗

PubMed1996

Dysmorphologic features of the fetal pelvis in Down syndrome: prenatal sonographic depiction and diagnostic implications of the iliac angle.

PURPOSE: To determine whether the axial pelvic profile is morphologically different in fetuses with Down syndrome from those with a normal karyotype. MATERIALS AND METHODS: Pelvic images were selected from ultrasound studies in 27 fetuses with trisomy 21 and in 135 fetuses with a normal karyotype. An observer blinded to study results measured the angle formed by the convergence of lines drawn tangent to the wing of the ilium. This angle was measured prospectively in 20 normal fetuses by four independent observers to estimate variability. RESULTS: The iliac bones could be assessed in 19 fetuses with trisomy 21 and in 87 fetuses with a normal karyotype. Between 15 and 20 weeks of gestation, the mean iliac angle was 60 degrees in normal fetuses and 75 degrees in fetuses with Down syndrome (P < .001). Intra- and interobserver correlation coefficients were .70 and .62, respectively. The greatest variability in results was among fetuses (estimated variance, 72.5); smaller variance was seen with repeat measurements in the same fetus (34.7) and with measurements by different observers (9.1). CONCLUSION: The mean iliac angle in fetuses with Down syndrome is larger than that in fetuses without Down syndrome and may aid in weighing the risks of trisomy 21 against the risks of performing amniocentesis.

Down Syndrome↗