Comparative therapeutic efficacy and safety of type-II collagen (UC-II), glucosamine and chondroitin in arthritic dogs: pain evaluation by ground force plate.

The investigation was conducted on client-owned moderately arthritic dogs with two objectives: (i) to evaluate therapeutic efficacy of type-II collagen (UC-II) alone or in combination with glucosamine hydrochloride (GLU) and chondroitin sulphate (CHO), and (ii) to determine their tolerability and safety. Dogs in four groups (n = 7-10), were treated daily for a period of 150 days with placebo (Group-I), 10 mg active UC-II (Group-II), 2000 mg GLU + 1600 mg CHO (Group-III), and UC-II + GLU + CHO (Group-IV). On a monthly basis, dogs were evaluated for observational pain (overall pain, pain upon limb manipulation, and pain after physical exertion) using different numeric scales. Pain level was also measured objectively using piezoelectric sensor-based GFP for peak vertical force and impulse area. Dogs were also examined every month for physical, hepatic (ALP, ALT and bilirubin) and renal (BUN and creatinine) functions. Based on observations, significant (p < 0.05) reduction in pain was noted in Group-II, III, and IV dogs. Using GFP, significant increases in peak vertical force (N/kg body wt) and impulse area (N s/kg body wt), indicative of a decrease in arthritis associated pain, were observed in Group-II dogs only. None of the dogs in any group showed changes in physical, hepatic or renal functions. In conclusion, based on GFP data, moderately arthritic dogs treated with UC-II (10 mg) showed a marked reduction in arthritic pain with maximum improvement by day 150. UC-II, GLU and CHO operate through different mechanisms of action, and were well tolerated over a period of 150 days.

Strategic water planning for south east England: preparing for proposed development.

The South East of England has one of the fastest growing and economically active populations in Europe, with associated significant pressures from development, particularly housing and transport. Sustainable water management has been identified as a major issue for future development of the region. The South East England Regional Assembly and the Environment Agency have carried out a study to investigate the potential constraints that flood risk, water resources, and water quality may pose on development. The study aims to improve understanding in order to inform the revision of regional planning polices and suggest practical guidance for local authorities to implement such policies. Wide technical consultation was carried out with the Environment Agency, local planning authorities and development agencies. Threshold Assessment was investigated as a technique to assess the potential impacts on the environment of various levels of forecast growth within selected parts of the region. Initial results indicate the need for more strategic and better integrated planning which recognises environmental and development boundaries.

Nonstenotic internal carotid arteries: effects of age and blood pressure at the time of scanning on Doppler US velocity measurements.

PURPOSE: To assess the effects of age and blood pressure at the time of scanning on internal carotid artery velocities and cross-sectional diameter at Doppler ultrasonography (US). MATERIALS AND METHODS: During 12 months, 1,020 consecutive patients underwent internal carotid artery Doppler US. No or minimal arterial disease was found in 142 patients (67 women, 75 men). Blood pressure was recorded prior to examination. The angle-corrected internal carotid artery peak systolic and end-diastolic velocities were obtained. The effects of systolic blood pressure, diastolic blood pressure, pulse pressure, age, chronic hypertension, and medications for hypertension on velocities were evaluated by using linear regression analysis. RESULTS: Peak systolic velocity was influenced by age (P =.008), systolic blood pressure (P =.009), diastolic blood pressure (P =.003), and pulse pressure (P =.017) but not history of hypertension (P =.53) or antihypertensive medication use (P =.77). Increasing age decreased peak systolic velocity by 0.34 cm/sec/y. End-diastolic velocity was influenced by age (P <.001) but not by systolic, diastolic, or pulse pressure (all P values were >.13). CONCLUSION: Internal carotid artery peak systolic velocities decrease with advancing age and increase with increasing pulse pressure. The effects of blood pressure at the time of scanning are small, but isolated systolic hypertension could cause increases in spurious velocity.

Nonenhanced helical CT and US in the emergency evaluation of patients with renal colic: prospective comparison.

PURPOSE: To compare nonenhanced helical computed tomography (CT) with ultrasonography (US) for the depiction of urolithiasis. MATERIALS AND METHODS: During 9 months, 45 patients (mean age, 44 years; mean weight, 92.5 kg) prospectively underwent both nonenhanced helical CT (5-mm collimation; pitch of 1.5) and US of the kidneys, ureters, and bladder. US evaluation included a careful search for ureteral calculi. Presence of calculi and obstruction and incidental diagnoses were recorded. Clinical, surgical, and/or imaging follow-up data were obtained in all patients. The McNemar test was used to compare groups. RESULTS: Diagnoses included 23 ureteral calculi and one each of renal cell carcinoma, appendicitis, ureteropelvic junction obstruction, renal subcapsular hematoma, cholelithiasis, medullary calcinosis, and myelolipoma. CT depicted 22 of 23 ureteral calculi (sensitivity, 96%). US depicted 14 of 23 ureteral calculi (sensitivity, 61%). Differences in sensitivity were statistically significant (P: =.02). Specificity for each technique was 100%. When modalities were compared for the detection of any clinically relevant abnormality (eg, unilateral hydronephrosis and/or urolithiasis in patients with an obstructing calculus), sensitivities of US and CT increased to 92% and 100%, respectively. One case of appendicitis was missed at US, whereas medullary calcinosis and myelolipoma were missed at CT. CONCLUSION: Nonenhanced CT has a higher sensitivity for the detection of ureteral calculi compared with US.

Physician training requirements in sonography: how many cases are needed for competence?

OBJECTIVE: Physician competence in the performance of sonographic studies was assessed after their involvement in predetermined increments of cases to determine whether the case volumes currently required by the American Institute of Ultrasound in Medicine and the American College of Radiology for training in sonography can be lowered substantially. MATERIALS AND METHODS: Sonographic competence tests were administered to 10 first-year diagnostic radiology residents after their involvement in increments of 50 cases, up to a total of 200 cases (four competency tests). Each competency test consisted of the resident's independently scanning and interpreting 10 clinically mandated studies that were scored in comparison with the examination performed by the sonographer and interpreted by an attending radiologist. Trainee studies were graded on the percentage of anatomic landmarks depicted, the number of reporting errors, the number of clinically significant reporting errors, and the percentage of cases receiving a passing score. RESULTS: Although resident performance improved progressively with increasing experience for all parameters assessed, performance of the group was poor even after their involvement in 200 cases. At this testing level, the mean percentage of anatomic landmarks depicted successfully was 56.5%; the mean total reporting errors per case was 1.2; the mean clinically significant errors per case was 0.5; and the mean percentage of cases receiving a passing score was 16%. Impressive performance differences were observed among residents for all parameters assessed, and these differences were not explained by the number of months of radiology training the resident had taken before the sonography rotation. CONCLUSION: Involvement in 200 or fewer cases during the training period is not sufficient for physicians to develop an acceptable level of competence in sonography.

Vertebral artery Doppler waveform changes indicating subclavian steal physiology.

OBJECTIVE: The goal of this study was to characterize and classify changes in antegrade vertebral artery waveforms that may represent the early stages of subclavian steal physiology. SUBJECTS AND METHODS: A prospective examination of waveforms from 1914 vertebral arteries produced a total of 40 that had a transient sharp decline in velocities at mid or late systole. In these patients, an ECG tracing was synchronized with the pulsed Doppler waveform, and reactive hyperemia was induced in the ipsilateral arm with a blood pressure cuff. The same protocol was performed in a control group of 52 patients with normal vertebral artery waveforms. Correlation between the waveforms and subclavian disease shown on angiography was made in 10 cases collected from the prospective study and in an additional 10 cases identified from a record search. RESULTS: Four prototypic waveforms were identified on the basis of the degree of flow deceleration in mid systole. Flow velocity at the nadir of the mid systolic notch was greater than that of the end diastole for type 1 waveforms, equal to the end diastole for type 2, at the baseline for type 3, and below the baseline for type 4. The blood pressure cuff maneuver induced a change to more abnormal waveforms in 36 of 40 patients but did not change the waveforms of the control group. The correlation between waveform type and subclavian disease was statistically significant (p = 0.03). CONCLUSION: Identifiable changes in the pulse contour of antegrade vertebral artery waveforms seem to represent the early stages of subclavian steal physiology. These changes can be organized into waveform types that indicate increasingly abnormal hemodynamics.

Variability of Doppler US measurements along the common carotid artery: effects on estimates of internal carotid arterial stenosis in patients with angiographically proved disease.

PURPOSE: To determine the effect of variability of common carotid arterial (CCA) velocities on velocity ratios used to assess internal carotid arterial (ICA) stenosis. MATERIALS AND METHODS: Doppler ultrasonographic (US) velocity measurements were obtained at three levels in the CCA and in the carotid bulb and ICA in all patients referred for carotid US between September 1996 and October 1997. Only ICAs (n = 98, in 57 patients) without ipsilateral CCA disease at angiography were analyzed. The range of CCA peak systolic velocities (PSVs) and end diastolic velocities (EDVs) and velocity ratios were calculated for each CCA measurement. For each ICA/CCA velocity ratio, receiver operating characteristic analysis was performed. RESULTS: CCA PSV and EDV ranges averaged 23.1 cm/sec +/- 15.7 (SD) and 5.1 cm/sec +/- 3.6, respectively. For a given side, the difference averaged 1.0 +/- 1.3 for PSV ratios and 2.7 +/- 6.9 for EDV ratios, depending on where CCA measurements were taken. By using a threshold of 60% stenosis as indication for endarterectomy, variability in CCA velocities could have altered recommendations in 16 (28%) of 57 patients. Receiver operating characteristic analysis showed that ratios made by using the three CCA velocities or their mean were not significantly different. CONCLUSION: Variability in velocity measurements along the course of the CCA in patients with ICA disease can be substantial and can result in inaccuracies in assessment of carotid stenosis.

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%.

PACS in sonography: accuracy of interpretation using film compared with monitor display. Picture archiving and communication systems.

OBJECTIVE: The goal of this study was to determine the relative accuracy of interpretation of sonography when viewed on a monitor or on film. MATERIALS AND METHODS: Four radiologists twice interpreted a series of 440 sonograms using the following sequences of display formats for initial and second interpretations: film-film, film-monitor, monitor-film, and monitor-monitor. Reporting discrepancies between the initial and subsequent interpretation were reviewed by an arbitration panel unaware of the display mode. Results were analyzed for differences in error rate attributable to film versus monitor display format, chronology of interpretation, individual observer, and observer seniority. RESULTS: We found no statistically significant difference in the error rate for film (10.3%) versus monitor display format (14.6%) (p = .09). Likewise, we found no significant differences in the error rates attributable to chronology of interpretation (p = .13), individual observer (p = .54), or observer seniority (p = .87). CONCLUSION: Interpretative accuracy is similar whether sonograms are interpreted on a monitor or on film.

Assessment of stenosis: implications of variability of Doppler measurements in normal-appearing carotid arteries.

PURPOSE: To examine the variability of Doppler measurements along the extra-cranial courses of the nondiseased common carotid artery (CCA) and internal carotid artery (ICA) and determine the effect of this variability on assessment of carotid arterial stenosis. MATERIALS AND METHODS: During the study period, 580 patients were referred for carotid arterial ultrasonography (US), including Doppler measurements of flow velocities in the proximal, middle, and distal portions of the CCA, in the bulb, and in the proximal and distal portions of the ICA. Eighty-five patients (average age, 59 years) with normal ICAs and CCAs formed the cohort for this study. RESULTS: The range of peak systolic velocity (PSV) measurement (maximum minus minimum) averaged 20 cm/sec +/- 13 in the CCA and 15 cm/sec +/- 13 in the ICA. ICA/CCA velocity ratios varied, depending on the CCA measurement location. In five arteries, PSV ratios exceeded a threshold of 1.8 (suggesting > or = 60% stenosis); in 23 arteries, end diastolic velocity ratios exceeded a threshold of 2.4 (also suggesting > or = 60% stenosis). Right-to-left CCA PSV ratios were abnormal in up to 26 patients (suggesting > 50% ICA stenosis), depending on where CCA measurements were obtained. When the CCA ratios were obtained at the same level, 16 were in the abnormal range. CONCLUSION: Variability of Doppler measurements in the CCA and ICA in patients without visible disease is substantial and could lead to inaccuracies in carotid arterial stenosis assessment.

Sonographic estimates of vein size in the lower extremities: subjective assessment compared with direct measurement.

PURPOSE: We studied whether subjective impression of vein size is a valid means of assessment during sonographic evaluation for deep vein thrombosis. METHODS: Diameter was assessed at 5 predetermined venous segments on 975 legs of 721 patients referred for evaluation for lower extremity deep vein thrombosis. The sonographer recorded a subjective assessment of whether the venous segment was enlarged, normal, or narrowed based on a visual impression of sonographic images obtained without compression. This subjective impression was then compared with the absolute measurements of vein diameter and vein diameter:artery diameter ratio at each segment. RESULTS: A significant correlation was found between the subjective characterization of vein size as enlarged, normal, and narrowed and both the absolute vein diameter and the vein:artery ratio at all 5 segments. CONCLUSIONS: Vein size can be reliably categorized by the subjective impression of experienced sonographers. Therefore, actual measurement of the vein diameter is not necessary in the evaluation for deep vein thrombosis in the majority of patients.

Flow quantification using fast cine phase-contrast MR imaging, conventional cine phase-contrast MR imaging, and Doppler sonography: in vitro and in vivo validation.

OBJECTIVE: Our purpose was to assess the accuracy of measurements of flow velocity and volume flow rate in an in vitro phantom and in healthy human volunteers using a cardiac-gated, segmented K-space, fast cine phase-contrast (PC) MR imaging technique with view sharing (fast PC). We compared this method with conventional cine PC MR imaging and Doppler sonography. SUBJECTS AND METHODS: Pulsatile flow was generated in a flow phantom that consisted of a cylindric tube having various degrees of tapered stenosis. Phase-encoded velocity maps were obtained using cine PC and fast PC MR imaging. Doppler sonography was also performed. Measurements of aortic and pulmonary artery peak systolic and minimum diastolic velocity and volume flow rate were then compared in eight healthy volunteers using the three imaging techniques. RESULTS: We found excellent agreement between fast PC and cine PC measurements of peak systolic velocity when regions of interest were drawn to exclude vessel margins (r > .99 for phantom studies, and r = .80 for human studies). Correlation between minimum diastolic velocity measurements by MR imaging was limited by noise that resulted from high encoding velocity settings. However, such correlation improved with signal averaging. When compared with predicted values of volume flow rates, both cine PC (r > .99) and fast PC (r = .97) MR imaging were more accurate than Doppler sonography (r = .78) in vitro. Measurements of cardiac output were adversely affected by low signal to noise, especially during diastole; estimates based on systolic forward flow resulted in better agreement between the two MR imaging methods. CONCLUSION: Fast PC MR flow quantification may prove to be a useful adjunct to routine MR studies for measurements of peak flow velocity. However, estimates of volume flow rate using fast PC MR imaging are limited because of increased noise during low diastolic flow as well as edge artifacts.

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.

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.

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.

Carotid ultrasound.

Carotid ultrasonography has become the preferred imaging technique for screening patients with suspected atherosclerotic cerebrovascular disease. The principles underlying duplex Doppler sonography and color and power Doppler ultrasonography are discussed. A standard approach to the performance and interpretation of carotid ultrasonography is presented, together with a discussion of potential diagnostic pitfalls. Brief discussion of transcranial Doppler and vertebral sonography are included.

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.

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.