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1.
Abdom Radiol (NY) ; 49(4): 1031-1041, 2024 04.
Article En | MEDLINE | ID: mdl-38195800

PURPOSE: While regarded as a secondary sign of pediatric appendicitis, the frequency of physiologic intra-abdominal fluid in children with suspected but absent appendicitis is unknown. Ex vivo: to assess the validity of US/MRI measurements of free fluid. In vivo: in suspected pediatric appendicitis, to assess the amount of abdominal fluid by US and MRI, determine performance characteristics of US in fluid detection and identify fluid volume ranges in confirmed appendicitis. METHODS: Ex vivo: criterion validity of US and MRI for fluid volume measurements was tested using tissue-mimicking phantoms filled with different volumes of distilled water. In vivo: all participants from a previous prospective study of suspected appendicitis were evaluated by US; MRI was performed after equivocal USs. Qualitative and quantitative analyses of abdominal fluid and correlation of fluid presence with appendicitis were performed. RESULTS: Ex vivo: no difference was found between phantom-fluid amount and measured volume using the formula for volume of an ellipsoid for US (P=0.19) or MRI (P=0.08). In vivo: intra-abdominal fluid was present in 212/591 (35.9%) patients; 75/212 patients with fluid (35.4%) had appendicitis, 60 (28.3%) had alternate diagnoses, and 77 (36.3%) had physiologic fluid. Sensitivity and specificity of US for fluid detection were 84% (95% CI 71-93) and 65% (95% CI 52-77), respectively. In children with versus without appendicitis, the respective ranges of fluid volume were 0.7-1148.8 ml and 0.8-318 ml. CONCLUSION: The volume of an ellipsoid formula is a valid method for quantifying intra-abdominal fluid. The sole presence of intra-abdominal fluid on US does not support the diagnosis of pediatric appendicitis.


Appendicitis , Child , Humans , Appendicitis/diagnostic imaging , Magnetic Resonance Imaging/methods , Sensitivity and Specificity , Prospective Studies , Ultrasonography/methods , Abdomen/diagnostic imaging , Abdomen/pathology , Retrospective Studies
2.
Insights Imaging ; 12(1): 132, 2021 Sep 25.
Article En | MEDLINE | ID: mdl-34564747

BACKGROUND: Intra-articular bleeds in patients with inherited bleeding disorders lead to active synovitis which may progress to a chronic state over time. We explored the diagnostic value of color Doppler ultrasound in detecting synovitis in boys with bleeding disorders. RESULTS: Sixty boys with hemophilia and 3 boys with type 3 von Willebrand disease aged 5 to 18 years (median 12.3 years) were imaged by gray-scale and color Doppler ultrasound (US) in three centers (Beijing, China [n = 22], Guangzhou, China [n = 12] and Toronto, Canada [n = 29])) in this observational study. Images were independently reviewed by two radiologists blinded to clinical data using a subjective semi-quantitative scoring system and objective measurements of synovial thickness and vascularity. Inter-reader reliability for using subjective versus objective color Doppler US methods for assessing synovial vascularity was excellent for the subjective method and moderate/lower range of substantial for the objective method. Agreement between degree of vascularity on color Doppler and extent of synovial hypertrophy on gray-scale US was overall poor for Canada data and moderate for China data. Correlations between degree of vascularity on color Doppler and synovial hypertrophy on gray-scale US, and clinical constructs (total and itemized HJHS scores and total Pettersson X-ray scores) for assessment of blood-induced arthropathy were all poor. CONCLUSION: Color Doppler US is a valuable scoring method for evaluating reactive synovitis in joints of subjects with inherited bleeding disorders and holds potential for assessing post-bleed reactive synovitis once further information on its association with timing of the joint bleed becomes available in the literature.

3.
Ultrasound Med Biol ; 46(12): 3218-3227, 2020 12.
Article En | MEDLINE | ID: mdl-32951932

Assessment and monitoring of inflammation and tissue damage is crucial in localized scleroderma (LS), but validated diagnostic tools are lacking. We aimed to determine the feasibility of using acoustic radiation force imaging ultrasound elastography in the assessment of pediatric-onset LS lesions. Conventional ultrasound and shear-wave elastography (SWE) imaging were used to characterize changes in pre-assigned LS lesions in 13 prospectively recruited participants. Contralateral sites were used as controls. Mean SWE values were compared. LS lesions were significantly stiffer than control sites in the dermis and the hypodermis using both parametric and non-parametric tests, before and after skin-thickness normalization. We show that SWE imaging is a feasible way to discriminate between normal skin and LS lesions in the pediatric population.


Elasticity Imaging Techniques , Scleroderma, Localized/diagnostic imaging , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Feasibility Studies , Female , Humans , Male , Prospective Studies
4.
Circ Cardiovasc Interv ; 13(7): e009251, 2020 07.
Article En | MEDLINE | ID: mdl-32611203

BACKGROUND: Transradial intervention is increasingly replacing approaches, due to lower access complications, cost, and improved patient satisfaction. There are limited supporting data in the pediatric literature, largely due to concerns regarding arterial size. The objective of this study was to measure radial artery diameters in children across all age groups, to establish reference ranges for clinical use. METHODS: This prospective study was carried out in children ≤18 years of age who underwent ultrasound for measuring radial artery diameters from November 2018 to November 2019. The cohort was divided into age groups: ≤2, 3 to 5, 6 to 8, 9 to 11, 12 to 14, 15 to 18 years, and into pre- and post-adolescent (≥12 years) groups. RESULTS: One hundred thirty-four children (M:F=63:71) were included, with bilateral measurements resulting in 268 data points. Mean age was 8.9±5.8 years (range, 29 days to 18 years), mean weight 37.2±27.5 kg (range, 1.7-149.1 kg). Mean-corrected radial artery diameter was 1.86±0.44 mm. There was no difference in arterial diameters between males and females (1.90±0.50 versus 1.81±0.53 mm; P=0.73) or between right and left sides (1.87±0.46 versus 1.87±0.47, P=0.98). There was a strong correlation of diameter with age (R=0.75; P<0.00001) and weight (R=0.74; P<0.00001). There was linear increase in arterial growth rates in early childhood, followed by plateauing to adult sizes in adolescents. Inter-reader agreement was 0.95. CONCLUSIONS: We provide a reference range for radial artery diameters across childhood ages, which can be used for decision-making. This could be the basis for designing a trial of transradial intervention in children, to establish clinical safety and efficacy.


Catheterization, Peripheral , Radial Artery/diagnostic imaging , Ultrasonography , Adolescent , Age Factors , Catheterization, Peripheral/adverse effects , Child , Child, Preschool , Clinical Decision-Making , Female , Humans , Infant , Male , Predictive Value of Tests , Prospective Studies , Punctures , Reference Values
5.
Ultrasound Med Biol ; 45(8): 1918-1923, 2019 08.
Article En | MEDLINE | ID: mdl-31104865

The purpose of this study was to quantify the stiffness of hypertrophic scars using acoustic radiation force impulse ultrasound elastography. Sixteen pediatric patients with hypertrophic scars resulting from burn injuries participated in this study (mean age: 5.13, standard deviation: 3.20). Values for the elastic modulus (E) of scar and control sites were obtained. Scarred areas were found to be almost four times stiffer than control sites (scar Emean = 39.29 kPa compared with control Emean = 10.19 kPa) (p = 0.0004). Correlations between scar stiffness and clinician-reported subjective scar scale scores were not observed (rs = 0.30, p = 0.27 and rs = 0.25, p = 0.35 respectively). We found that acoustic radiation force impulse imaging can discriminate between hypertrophic scars and normal skin and should be considered a potentially valuable tool in the armamentarium of objective scar measures. Future research should focus on evaluating the technology's ability to detect scar change over time in order to determine responsiveness to treatment.


Burns/complications , Cicatrix/diagnostic imaging , Cicatrix/physiopathology , Elasticity Imaging Techniques/methods , Acoustics , Child , Child, Preschool , Cicatrix/etiology , Elastic Modulus , Female , Humans , Infant , Longitudinal Studies , Male
6.
Acad Emerg Med ; 22(4): 406-14, 2015 Apr.
Article En | MEDLINE | ID: mdl-25808065

OBJECTIVES: The primary objective was to determine the diagnostic accuracy of a serial ultrasound (US) clinical diagnostic pathway to detect appendicitis in children presenting to the emergency department (ED). The secondary objective was to examine the diagnostic performance of the initial and interval US and to compare the accuracy of the pathway to that of the initial US. METHODS: This was a prospective cohort study of 294 previously healthy children 4 to 17 years old with suspected appendicitis and baseline pediatric appendicitis scores of ≥2, who were managed with the serial US clinical diagnostic pathway. This pathway consisted of an initial US followed by a clinical reassessment in each patient and an interval US and surgical consultation in patients with equivocal initial US and persistent concern about appendicitis. The USs were interpreted by published criteria as positive, negative, or equivocal for appendicitis. Children in whom this pathway did not rule in or rule out appendicitis underwent computed tomography (CT). Cases with missed appendicitis, negative operations, and CTs after the pathway were considered inaccurate. The primary outcome was the diagnostic accuracy of the serial US clinical diagnostic pathway. The secondary outcomes included the test performance of the initial and interval US imaging studies. RESULTS: Of the 294 study children, 111 (38%) had appendicitis. Using the serial US clinical diagnostic pathway, 274 of 294 children (93%, 95% confidence interval [CI] = 90% to 96%) had diagnostically accurate results: 108 of the 111 (97%) appendicitis cases were successfully identified by the pathway without CT scans (two missed and one CT), and 166 of the 183 (91%) negative cases were ruled out without CT scans (14 negative operations and three CTs). The sensitivity of this pathway was 108 of 111 (97%, 95% CI = 94% to 100%), specificity 166 of 183 (91%, 95% CI = 87% to 95%), positive predictive value 108 of 125 (86%; 95% CI = 79% to 92%), and negative predictive value 166 of 169 (98%, 95% CI = 96% to 100%). The diagnostic accuracy of the pathway was higher than that of the initial US alone (274 of 294 vs. 160 of 294; p < 0.0001). Of 123 patients with equivocal initial US, concern about appendicitis subsided on clinical reassessment in 73 (no surgery and no missed appendicitis). Of 50 children with persistent symptoms, 40 underwent interval US and 10 had surgical consultation alone. The interval US confirmed or ruled out appendicitis in 22 of 40 children (55.0%) with equivocal initial US, with one false-positive interval US. CONCLUSIONS: The serial US clinical diagnostic pathway in suspected appendicitis has an acceptable diagnostic accuracy that is significantly higher than that of the initial US and results in few CT scans. This approach appears most useful in children with equivocal initial US, in whom the majority of negative cases were identified at clinical reassessment and appendicitis was diagnosed by interval US or surgical consultation in most study patients.


Appendicitis/diagnostic imaging , Appendicitis/diagnosis , Critical Pathways , Emergency Service, Hospital/organization & administration , Acute Disease , Adolescent , Child , Child, Preschool , Female , Humans , Male , Physical Examination , Prospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed , Ultrasonography
7.
AJR Am J Roentgenol ; 204(3): W336-47, 2015 Mar.
Article En | MEDLINE | ID: mdl-25714320

OBJECTIVE. The purpose of this article is to assess the reliability of interpretation of ultrasound findings according to data blinding in maturing hemophilic joints and to determine the diagnostic accuracy of ultrasound compared with MRI for assessing joint components. SUBJECTS AND METHODS. Ankles (n = 34) or knees (n = 25) of boys with hemophilia or von Willebrand disease (median age, 13 years; range, 5-17 years) were imaged by ultrasound, MRI, and radiography in two centers (Toronto, Canada, and Vellore, India). Ultrasound scans were performed by two operators (one blinded and one unblinded to MRI data) and were reviewed by four reviewers who were unblinded to corresponding MRI findings according to a proposed 0- to 14-item scale that matches 14 of 17 items of the corresponding MRI scale. MRI examinations were independently reviewed by two readers. RESULTS. When data were acquired by radiologists, ultrasound was highly reliable for assessing soft-tissue changes (intraclass correlation coefficient [ICC], 0.98 for ankles and 0.97 for knees) and substantially to highly reliable for assessing osteochondral changes (ICC, 0.61 for ankles and 0.89 for knees). Ultrasound was highly sensitive (> 92%) for assessing synovial hypertrophy and hemosiderin in both ankles and knees but had borderline sensitivity for detecting small amounts of fluid in ankles (70%) in contrast to knees (93%) and variable sensitivity for evaluating osteochondral abnormalities (sensitivity range, 86-100% for ankles and 12-100% for knees). CONCLUSION. If it is performed by experienced radiologists using a standardized protocol, ultrasound is highly reliable for assessing soft-tissue abnormalities of ankles and knees and substantially to highly reliable for assessing osteochondral changes in these joints.


Joint Diseases/diagnostic imaging , Joint Diseases/pathology , Magnetic Resonance Imaging , Adolescent , Ankle Joint , Child , Child, Preschool , Female , Hemophilia A/complications , Humans , Joint Diseases/etiology , Knee Joint , Male , Prospective Studies , Reproducibility of Results , Ultrasonography , von Willebrand Diseases/complications
8.
J Magn Reson Imaging ; 38(3): 733-8, 2013 Sep.
Article En | MEDLINE | ID: mdl-23148038

PURPOSE: To compare measurements of blood flow velocity (BFV) and BFV changes in the middle cerebral arteries (MCA) acquired from phase contrast magnetic resonance angiography (PCMRA) and transcranial Doppler ultrasound (TCD) during controlled manipulation of end-tidal partial pressure of carbon dioxide (PetCO2 ). MATERIALS AND METHODS: In vivo TCD and PCMRA velocity data from the M1 segment in the MCA of nine healthy adult volunteers were acquired during precise targeting of PetCO2 induced by a computer-controlled gas delivery system. Doppler spectra and phase contrast data were processed into time-averaged peak-velocity (TAPV) values for comparison. Changes in velocity between baseline and hypercapnia were analyzed in terms of velocity-based cerebrovascular reactivity (CVR). RESULTS: Good correlation between the pairs of velocity measurements acquired from the two modalities were found (ρ = 0.81), but Bland-Altman analysis indicates a significant bias error. There was relatively weak agreement between the pairs of computed CVR values (ρ = -0.26). CONCLUSION: Under precise PetCO2 control, PCMRA proves to be more consistent than TCD. Despite issues with variability, TCD is qualitatively comparable to PCMRA measures of velocity in the MCA. However, PCMRA velocity results are better suited for analyses that require quantitative values, such as CVR.


Carbon Dioxide/administration & dosage , Cerebrovascular Circulation/physiology , Magnetic Resonance Angiography/methods , Middle Cerebral Artery/physiology , Ultrasonography, Doppler, Transcranial/methods , Administration, Inhalation , Adult , Blood Flow Velocity/drug effects , Cerebrovascular Circulation/drug effects , Humans , Male , Middle Cerebral Artery/anatomy & histology , Middle Cerebral Artery/diagnostic imaging , Reproducibility of Results , Sensitivity and Specificity , Vasoconstrictor Agents/administration & dosage , Young Adult
9.
J Pediatr ; 158(1): 112-8, 2011 Jan.
Article En | MEDLINE | ID: mdl-20828717

OBJECTIVE: To determine predictors of diagnostically inaccurate ultrasound scanning for suspected appendicitis. STUDY DESIGN: Prospective emergency department cohort study of 263 previously healthy children 4 to 17 years of age undergoing ultrasound scanning. Ultrasound scanning results were interpreted as positive, negative, or equivocal for appendicitis and classified as diagnostically accurate and inaccurate. The main outcome measure was association between inaccurate ultrasound scanning and age, sex, body mass index percentiles, pain duration, white blood cell count, Faces Pain Score-Revised, clinical probability of appendicitis, and ultrasound scanning operator. RESULTS: Of the 263 patients, 95 ultrasound scanning examinations were read as positive, 76 as negative, and 92 were equivocal. A total of 162 (61.6%) ultrasound scanning examinations were accurate (TP86, TN76), and 101 (38.4%) ultrasound scanning examinations were inaccurate (FP88, FN13). Children with body mass index percentiles ≥ 85 and clinical probability of appendicitis ≤ 50% had 58.1% probability of inaccurate ultrasound scanning examination (odds ratio, 2.48; 95% confidence interval, 1.48-2.78). In lean children, diagnostic accuracy of the screening ultrasound scanning examination with second ultrasound scanning or clinical reassessment was 93% versus 83% in the obese children (95% confidence interval of the difference, 1-19%). CONCLUSION: Screening ultrasound scanning for pediatric appendicitis has suboptimal accuracy, particularly in obese children with a low likelihood of appendicitis who should not routinely undergo ultrasound scanning. However, when followed by a second ultrasound scanning or a clinical reassessment, it offers high diagnostic accuracy in lean children.


Appendicitis/diagnostic imaging , Adolescent , Child , Child, Preschool , Female , Humans , Male , Predictive Value of Tests , Prospective Studies , Ultrasonography
10.
Dermatology ; 223(4): 363-9, 2011.
Article En | MEDLINE | ID: mdl-22327486

BACKGROUND/AIMS: Therapeutic options for the treatment of plaque morphea are limited. We explored the efficacy and safety of imiquimod cream in children with plaque morphea. METHODS: Prospective, open-label, double-baseline study, using imiquimod 5% cream topically for 9 months. The primary outcome measure was improvement in the thickening of morphea plaques using a visual analog scale (VAS) and the DIET score (dyspigmentation/induration/erythema/telangiectasia). Secondary outcome measures were clinicoradiographic correlations and frequency of adverse events. RESULTS: Nine patients, 89% females, with a mean age of 11.33 years (SD = 3.52) were enrolled. At 36 weeks, the mean VAS had decreased from 48.08 (SD = 18.85) to 22.7 (SD = 12.9) (p < 0.0001), and the mean DIET score from 4.38 (SD = 1.2) to 3.06 (SD = 1.39) (p = 0.23). There was very good interrater reliability between DIET score assessments (intraclass correlation coefficient, ICC = 0.75) and VAS (ICC = 0.59) and moderate agreement between parent and investigator VAS (ICC = 0.5). Ultrasonographically measured dermis thickness changed from 1.05 (SD = 0.34) to 0.95 (SD = 0.19) (p = 0.001). One patient experienced ulceration that required temporary discontinuation of intervention. CONCLUSIONS: This proof of concept study revealed that imiquimod 5% cream is effective in decreasing the thickening of plaque morphea and safe for pediatric use. Further prospective studies are warranted.


Adjuvants, Immunologic/therapeutic use , Aminoquinolines/therapeutic use , Scleroderma, Localized/drug therapy , Adjuvants, Immunologic/adverse effects , Adolescent , Aminoquinolines/adverse effects , Child , Dermis/diagnostic imaging , Dermis/drug effects , Female , Humans , Imiquimod , Male , Ointments , Pilot Projects , Prospective Studies , Scleroderma, Localized/diagnostic imaging , Skin Ulcer/chemically induced , Treatment Outcome , Ultrasonography
11.
Radiographics ; 30(5): 1287-307, 2010 Sep.
Article En | MEDLINE | ID: mdl-20833851

In neonates and children, sonographic examinations of the renal pyramids may depict a spectrum of unique changes in echogenicity due to the effects of physiologic processes or a wide variety of pathologic processes that may affect the collecting ducts or interstitium of the pyramids. Focused sonographic evaluation of the pyramids with high-frequency transducers produces the most detailed images of the pyramids, revealing some appearances not previously reported, to the authors' knowledge. The authors highlight the clinical settings in which they have documented detailed changes in the echogenicity of the pyramids. The patterns of altered echogenicity alone may reflect a specific cause but in many instances are nonspecific, with clinical and biochemical correlation required to establish a more precise diagnosis. However, there is a lack of histologic data to completely explain the mechanism of many of these changes in echogenicity in all of the processes. As the authors have expanded their use of the focused sonographic technique, they have been able to depict altered echogenicity in the pyramids in greater numbers of children in whom an explanation for the changes is not always immediately apparent; for now, the cause must be considered idiopathic. More work is required to expand the use of this focused technique together with clinical, biochemical, and histologic correlation in an attempt to offer more complete explanations for the changes in echogenicity of the pyramids.


Image Enhancement/methods , Kidney Diseases/diagnostic imaging , Kidney/abnormalities , Kidney/diagnostic imaging , Ultrasonography/methods , Child , Female , Humans , Infant, Newborn , Male
12.
Pediatr Rheumatol Online J ; 8: 14, 2010 Apr 27.
Article En | MEDLINE | ID: mdl-20423513

BACKGROUND: Our earlier work in the ultrasonograpy of localized scleroderma (LS) suggests that altered levels of echogenicity and vascularity can be associated with disease activity. Utrasound is clinically benign and readily available, but can be limited by operator dependence. We present our efforts to standardize image acquisition and interpretation of pediatric LS to better evaluate the correlation between specific sonographic findings and disease activity. METHODS: Several meetings have been held among our multi-center group (LOCUS) to work towards standardizing sonographic technique and image interpretation. Demonstration and experience in image acquisition were conducted at workshop meetings. Following meetings in 2007, an ultrasound measure was developed to standardize evaluation of differences in echogenicity and vascularity. Based upon our initial observations, we have labeled this an ultrasound disease activity measure. This preliminary measure was subsequently evaluated on over 180 scans of pediatric LS lesions. This review suggested that scoring levels should be expanded to better capture the range of observed differences. The revised levels and their definitions were formulated at a February 2009 workshop meeting. We have also developed assessments for scoring changes in tissue thickness and lesion size to better determine if these parameters aid evaluation of disease state. RESULTS: We have standardized our protocol for acquiring ultrasound images of pediatric LS lesions. A wide range of sonographic differences has been seen in the dermis, hypodermis, and deep tissue layers of active lesions. Preliminary ultrasound assessments have been generated. The disease activity measure scores for altered levels of echogenicity and vascularity in the lesion, and other assessments score for differences in lesion tissue layer thickness and changes in lesion size. CONCLUSIONS: We describe the range of sonographic differences found in pediatric LS, and present our efforts to standardize ultrasound acquisition and image interpretation for this disease. We present ultrasound measures that may aid evaluation of disease state. These assessments should be considered a work in progress, whose purpose is to facilitate further study in this area. More studies are needed to assess their validity and reliability.

13.
J Pediatr ; 152(5): 622-8, 2008 May.
Article En | MEDLINE | ID: mdl-18410763

OBJECTIVES: To describe the dermatological changes associated with continuous subcutaneous insulin infusion (CSII) therapy in youth with type 1 diabetes mellitus (T1D). To assess their association with duration of CSII, age, adiposity, HbA1(c), insulin dose, insulin brand, infusion set or site. STUDY DESIGN: We conducted a cross-sectional study of 50 consecutive patients with T1D who were using CSII for >6 months (26 female; age, 13.3 +/- 3.5 years [mean +/- SD]; CSII duration, 2.8 +/- 1.7 years; HbA1(c), 7.7% +/- 1.1%). A grading scale was devised. Ultrasound scanning was performed in 8 subjects. RESULTS: The mean (+/-SD) severity score was 6.3 +/- 3.5 (range, 0-14; maximum possible, 69). Most common were scars <3 mm diameter (94%), erythema not associated with nodules (66%), subcutaneous nodules (62%), and lipohypertrophy (42%). There was a significant negative correlation between severity score and body mass index z-score (r = -0.3, P = .039), but no correlation with HbA1(c), insulin brand or site. Infusion sets inserted at 90 degrees were associated with lower scores (P = .03). Less than 5% of patients and parents considered stopping CSII because of skin concerns. Ultrasound scanning results of CSII sites revealed mild increased echogenicity of the dermis and hypodermis. CONCLUSIONS: Dermatological changes were frequent, with increased severity associated with lower adiposity. These complications were not associated with glycemic control, nor did they prompt most to consider stopping CSII.


Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Insulin Infusion Systems/adverse effects , Insulin/administration & dosage , Insulin/adverse effects , Skin Diseases/etiology , Adiposity , Adolescent , Age Factors , Child , Cohort Studies , Cross-Sectional Studies , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/pathology , Female , Humans , Male , Severity of Illness Index , Skin Diseases/diagnostic imaging , Skin Diseases/pathology , Ultrasonography
14.
Pediatr Radiol ; 36(12): 1242-51, 2006 Dec.
Article En | MEDLINE | ID: mdl-17051358

BACKGROUND: Objective quantification is critical for assessment of functional sonography in inflammatory arthritis. To create a microbubble contrast-enhanced image of vessels that lie below the resolution of a standard US system, a technique is required that detects preferentially the contrast agent echo, rejecting that from background tissue: harmonic imaging. OBJECTIVES: To investigate the ability of contrast-enhanced triggered harmonic sonography (CETHS) to evaluate periarticular hemodynamic changes over the course of experimental arthritis and to discriminate presence and absence of arthritis based on measurement values obtained at specific time-points. MATERIALS AND METHODS: Arthritis was induced in rabbits knees by intra-articular injection of serum bovine albumin, which acted as an antigen. A total of 11 rabbits (8 with unilateral arthritis and 3 control animals) were imaged at 0, 1, 7, 14, 21 and 28 days of antigen-induced arthritis and euthanized at 28 days. A continuous infusion protocol was performed (triggering times 30.0, 20.0, 10.0, 5.0, 2.0, 1.0, and 0.5 s). Hemodynamic indices of synovial microvasculature (vascular volume, mean velocity and flow rate) were obtained and compared with clinical, laboratory, and histological surrogate markers. RESULTS: Although interval CETHS changes were noted for flow rate (P=0.007) and vascular volume (P=0.003) ratios in albumin-injected knees, no significant differences in ratios were identified over time between albumin-injected and non-injected knees for flow rate (P=0.52), vascular volume (P=0.23) and mean velocity (P=0.19). Flow rate most accurately differentiated between presence and absence of arthritis according to clinical measurements in early (day 1) arthritis, and mean velocity in mid-term arthritis (day 14; both P=0.02). CONCLUSION: Although the measurement properties of CETHS indices were poor in the evaluation of hemodynamic differences over time in albumin-injected knees compared with non-injected knees, they enabled discrimination between presence and absence of arthritis at specific time-points in different stages.


Arthritis, Experimental/diagnosis , Contrast Media/administration & dosage , Fluorocarbons , Hindlimb/diagnostic imaging , Image Enhancement/methods , Joints/diagnostic imaging , Animals , Area Under Curve , Blood Flow Velocity , Body Weights and Measures/methods , Disease Models, Animal , Hindlimb/blood supply , Image Processing, Computer-Assisted/methods , Injections, Intra-Articular , Joints/blood supply , Male , Microbubbles , ROC Curve , Rabbits , Sensitivity and Specificity , Serum Albumin/administration & dosage , Serum Amyloid A Protein , Sodium Chloride/administration & dosage , Synovial Membrane/ultrastructure , Time Factors , Ultrasonography
15.
Radiology ; 240(3): 821-7, 2006 Sep.
Article En | MEDLINE | ID: mdl-16857976

PURPOSE: To retrospectively evaluate the normal sonographic appearance of splenic parenchyma in children of various ages with high-frequency transducer sonography. MATERIALS AND METHODS: Research ethics committee board approval was obtained, with waiver of informed consent. We evaluated in vivo sagittal and transverse sonograms of spleens obtained with 13-MHz linear-array transducers in 100 children (age range, 1 day to 17 years) with clinically diagnosed disease that did not affect the lymphoid system. Three radiologists working in consensus defined the grading system for the splenic parenchyma. Thereafter, these same radiologists graded the sonographic reticulonodular pattern independently as granular, mild, or marked. These grades were cross correlated with clinical data by using logistic regression analysis and chi(2) tests. Sonographic measurements of the splenic parenchyma in nine pediatric cadavers separate from the in vivo cohort of the study were compared with those of corresponding histologic slices by means of linear correlation. RESULTS: Both grade 2 and grade 3 patterns occurred more frequently in children older than 1 year but no older than 5 years, whereas grade 1 pattern occurred most frequently in neonates (P < .001). As patients' age (odds ratio, 1.6; P < .001) and splenic dimensions (odds ratio, 3.1; P < .001) increased, the frequency with which the reticulonodular pattern was classified as either grade 2 or grade 3 increased. No association was noted between sonographic patterns and body mass index (P = .85) or sex (P = .07). The parenchymal nodules graded as 2 or 3 on sonograms correlated well with the presence of lymphoid follicles (white pulp) at histologic analysis (r = .71, P = .03). CONCLUSION: High-frequency transducer sonography of the spleen in children can demonstrate normal echo patterns that should not be misinterpreted as indicative of disease.


Spleen/diagnostic imaging , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Reference Values , Retrospective Studies , Spleen/anatomy & histology , Ultrasonography/methods
16.
Radiology ; 235(2): 587-94, 2005 May.
Article En | MEDLINE | ID: mdl-15858098

PURPOSE: To determine whether absence of bowel wall perfusion at color Doppler ultrasonography (US) is indicative of bowel necrosis in neonates with necrotizing enterocolitis (NEC). MATERIALS AND METHODS: This study was approved by the research ethics board, and informed consent was obtained. Sixty-two neonates enrolled in the prospective study underwent US of the bowel wall. Neonates were divided into two groups. Group A included 30 control subjects with gestational ages (GAs) ranging from 24 to 41 weeks. Group B included 32 neonates with GAs ranging from 24 to 40 weeks who were clinically proved to have or suspected of having NEC. All neonates in group B underwent abdominal radiography. Normative values were calculated in group A. In group B, the sensitivities and specificities of color Doppler US and abdominal radiography for detection of bowel necrosis were computed by using the modified Bell staging criteria for NEC as the reference standard. RESULTS: Two neonates were excluded from group B; thus, a total of 60 neonates were included in the study. In group A, bowel wall thickness ranged from 1.1 to 2.6 mm. Bowel wall perfusion was detected with color Doppler US in all 30 neonates. Color Doppler signals ranged from one to nine dots per square centimeter. Twenty-two of 30 neonates in group B received a diagnosis of NEC. Mild to moderate NEC was diagnosed in 12 neonates. Color Doppler US depicted an isolated segment of bowel-absent blood flow in two neonates; this finding was confirmed with laparotomy. In 10 neonates with severe NEC, color Doppler US depicted isolated or multiple segments of bowel with absent perfusion. Pneumoperitoneum was present in only four neonates. The remaining eight neonates at risk for NEC had no evidence of loops without perfusion at color Doppler US. The sensitivity of free air at abdominal radiography as a positive sign for severe NEC with necrotic bowel was 40% compared with the 100% sensitivity of absence of flow at color Doppler US (P = .03). CONCLUSION: Color Doppler US is more accurate than abdominal radiography in depicting bowel necrosis in NEC.


Enterocolitis, Necrotizing/diagnostic imaging , Infant, Premature, Diseases/diagnostic imaging , Intestines/blood supply , Muscle, Smooth/blood supply , Tissue Survival/physiology , Ultrasonography, Doppler, Color , Enterocolitis, Necrotizing/pathology , Enterocolitis, Necrotizing/surgery , Female , Fourier Analysis , Humans , Infant, Newborn , Infant, Premature, Diseases/pathology , Infant, Premature, Diseases/surgery , Intestines/pathology , Intestines/surgery , Ischemia/diagnostic imaging , Male , Muscle, Smooth/pathology , Muscle, Smooth/surgery , Pneumoperitoneum/diagnosis , Prospective Studies , Reference Values , Regional Blood Flow/physiology , Sensitivity and Specificity
17.
AJR Am J Roentgenol ; 180(4): 1143-5, 2003 Apr.
Article En | MEDLINE | ID: mdl-12646472

OBJECTIVE: The purpose of this study was to illustrate the spectrum of sonographic findings in testicular torsion in a large series of neonates and infants. These patterns and their evolution have, to our knowledge, not been described previously. CONCLUSION: The sonographic appearance of testicular torsion in neonates and infants can be divided into three types. We believe that the findings represent different stages in the evolution of testicular torsion.


Spermatic Cord Torsion/congenital , Spermatic Cord Torsion/diagnostic imaging , Ultrasonography, Doppler, Color , Ultrasonography, Doppler, Pulsed , Blood Flow Velocity/physiology , Humans , Infant , Infant, Newborn , Infant, Premature, Diseases/diagnostic imaging , Infant, Premature, Diseases/surgery , Male , Orchiectomy , Retrospective Studies , Spermatic Cord Torsion/classification , Spermatic Cord Torsion/surgery , Testicular Hydrocele/diagnostic imaging , Testicular Hydrocele/surgery , Testis/blood supply , Testis/diagnostic imaging
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