Normal hip in children: correlation of US with anatomic and cryomicrotome sections

Full and simultaneous exploitation of features designed to maximize signal-to-noise ratio with the new generation of ultrasound equipment enabled detailed sonographic depiction of the anatomy of the hip and its surroundings. Scanning in familiar planes provided images that are easier to interpret. In addition, correlation of these images with cryomicrotome sections and histochemical studies disclosed several new findings. The articular cartilage of infant hips-composed mostly of water-is anechoic. However, the hyaline cartilage-which contains many vascular channels, columns of cartilage cells, and mesenchymal stroma-appears as alternating hypoechoic or anechoic columns and echogenic columns. The fibrocartilage of the limbus, on the other hand, is echogenic, as are other fibrous tissues. As expected, the points of attachment of the distal aspect of the synovial membrane, the fibrous capsule, and the ligaments in relation to the epiphyseal growth plate, varied with age, as did the characteristics of the cartilaginous structures. Familiarization with the sonographic appearance of normal hip anatomy in subjects of all ages is a first step toward recognition of various pathologic entities of the hip.     

Simple renal cysts in children: diagnosis and follow-up with US

To assess the sonographic frequency of simple renal cysts in children, the authors retrospectively reviewed the results of abdominal sonographic studies of 16,102 children performed over a 5-year period between January 1, 1985, and December 31, 1989. Patients with abnormal renal function, dysplastic kidneys, or a family history of polycystic kidney disease were excluded from the study. The authors' review of the sonograms revealed 37 simple cysts in 35 patients (0.22%); the cysts were evenly distributed by age and sex and measured from 0.3 to 7.0 cm in maximum diameter. Sixteen cysts (43%) were in the upper pole of the right kidney. Follow-up sonographic studies of 23 cysts in 22 patients for up to 5 years showed no change in size in 17 cysts (74%). The largest cyst was drained percutaneously; all other cysts were managed conservatively. No patient showed deterioration of renal function. Therefore, the authors concluded that in a pediatric patient demonstrating normal renal function, no further intervention is necessary when a simple renal cyst is identified at sonography.     

US, colour-Doppler US and fine-needle aspiration biopsy in the diagnosis of thyroid nodules

PURPOSE: The purpose of this study was to correlate the diagnosis of benign or malignant thyroid nodules obtained with grey-scale ultrasound (US) and colour-Doppler US with the cytological findings after US-guided fine-needle aspiration (FNA). MATERIALS AND METHODS: Between January 2004 and June 2005, 516 thyroid nodules in 420 patients (181 solitary thyroid nodules and 239 multiple nodules) were prospectively evaluated with US, colour-Doppler US and US-guided FNA. The nodules were classified as sonographically benign, suspicious or malignant in accordance with established US criteria. Cytological findings were classified as inadequate, benign, indeterminate, suspicious or malignant. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of US and colour-Doppler US were evaluated using FNA as the reference procedure. RESULTS: The sensitivity, specificity, PPV, NPV and overall accuracy values of grey-scale US were 46%, 73%, 34%, 82% and 67%, respectively, for solitary thyroid nodules and 35%, 72%, 14%, 90% and 68%, respectively, for multiple nodules. The evaluation of nodule vascularity with colour-Doppler US produced a slight increase in sensitivity but a slight reduction in specificity. CONCLUSIONS: Thyroid nodules cannot be accurately characterised using grey-scale US or colour-Doppler US.     

Transient synovitis of the hip in children: role of US

Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies.     

Pelvic masses: aspiration biopsy with transrectal US guidance

Biplanar, transrectal ultrasound guidance was used in the transrectal aspiration of two pelvic abscesses, one recurrent tumor, and one sterile, nonmalignant fluid collection. This method provides an alternative path that allows precise localization for aspiration biopsy of pelvic masses.     

Fetal cephaloceles: diagnosis with US

The prenatal sonograms of 15 fetuses with cephaloceles (13 occipital, one ethmoidal, and one frontoparietal) were retrospectively reviewed. The prognosis for fetuses with cephaloceles was poor: Only three of 14 with follow-up were born alive (21%), and all are likely to be handicapped. Karyotypes were abnormal in four of nine fetuses tested (44%). Associated cranial abnormalities observed in various numbers of fetuses included ventriculomegaly, the "lemon" sign, a flat basioccipital, "beaked" tectum, and bone defect. A wide variety of neural and nonneural anomalies were associated with cephaloceles. At least one sonographically observed concomitant neural or nonneural axis abnormality or an abnormal karyotype was present in nine of 15 fetuses (60%). Some associated neural malformations noted pathologically were not observed prenatally. Cranial meningoceles were not accurately distinguished from encephaloceles sonographically, and they also were associated with a poor prognosis. Comparison of findings in fetuses with cephaloceles with those of 15 fetuses with cystic hygromas revealed that the two abnormalities can usually be distinguished by the relationship of the mass with the neck and by other cranial findings present in fetuses with cephaloceles but absent in association with cystic hygromas.     

Anterior joint capsule of the normal hip and in children with transient synovitis: US study with anatomic and histologic correlation

PURPOSE: To study the anatomic components of the anterior joint capsule of the normal hip and in children with transient synovitis. MATERIALS AND METHODS: Six cadaveric specimens were imaged with ultrasonography (US) with special attention to the anterior joint capsule. Subsequently, two specimens were analyzed histologically. These anatomic findings were correlated with the US findings in 58 healthy children and 105 children with unilateral transient synovitis. RESULTS: The anterior joint capsule comprises an anterior and posterior layer, mainly composed of fibrous tissue, lined by only a minute synovial membrane. Both fibrous layers were identified separately at US in 98 of 116 (84%) hips of healthy subjects and in all hips with transient synovitis. Overall, the anterior layer was thicker than the posterior layer. In transient synovitis compared with normal hips, no significant thickening of both layers was present (P = .24 and .57 for the anterior and posterior layers, respectively). Normal variants include plicae, local thickening of the capsule, and pseudodiverticula. CONCLUSION: Increased thickness of the anterior joint capsule in transient synovitis is caused entirely by effusion. There is no US evidence for additional capsule swelling or synovial hypertrophy.     

Synovial effusion in reflex sympathetic dystrophy: an additional sign for diagnosis and staging

Purpose. To improve the present MRI criteria for diagnosis and staging of reflex sympathetic dystrophy (RSD) by including increased joint fluid as an additional MRI sign of RSD. Design and patients. One hundred and fourteen extremities (69 affected and 45 contralateral controls) in 57 consecutive patients with RSD were evaluated using a 1.5-T unit. T1- and T2-weighted pulse sequences, often with fat suppression, were used before and after administration of intravenous contrast enhancement (Gd). Following T2-weighted image digitization the volume of synovial fluid was measured with a computer model. Results. Effusions were detected in 61% of the extremities suspected of RSD and in 44% of the contralateral control joints. The mean fluid quantity measured in the symptomatic articulation was 201 mm³. MRI diagnosis of RSD based on previously described criteria was done in 62% of the patients, yielding a sensitivity of 60%. Effusions were present in 79% of the false negative MRI cases. Retrospectively considering the presence of fluid as a potential positive criterion for RSD increases the sensitivity by 31% (to 91%). Conclusions. Joint effusions are probably associated with early stages of RSD. Adding effusion to the list of radiological criteria for RSD increases the sensitivity of MRI from 60% to 91%.     

Thoracic duct cyst: diagnosis with needle aspiration

A case of an asymptomatic posterior mediastinal thoracic duct cyst diagnosed with fluoroscopically guided needle aspiration is reported. Previously, the diagnosis of thoracic duct cyst was established surgically and more recently was established by lymphangiography. To the authors' knowledge, diagnosis using needle aspiration has not been reported.     

Acute appendicitis in children: evaluation with US

During a 4-month period, high-resolution ultrasonography (US) was used to prospectively evaluate 70 children with clinically suspected acute appendicitis. Thirty-five US scans showed a noncompressible appendix with maximal outer diameters greater than 6 mm. This finding was considered positive for the diagnosis of acute appendicitis. Thirty-one of these 35 patients had acute appendicitis documented by surgical and pathologic findings. The remaining four patients were observed, and their symptoms resolved. Thirty-five patients had US scans considered negative for appendicitis. Seventeen of these patients had US findings positive for other conditions including mesenteric adenitis, ileitis, intussusception, Crohn disease, and Burkitt lymphoma. In this series US enabled diagnosis of acute appendicitis with a sensitivity of 94%, a specificity of 89%, and a predictive accuracy of 91%. Diagnosis of acute appendicitis can be made with US with the same accuracy in children as has been previously reported in series of adult patients. The use of US in clinically ambiguous cases may allow earlier diagnosis, prevention of perforation, and decreased complications in the pediatric patient with acute appendicitis.     

Bladder dysfunction: diagnosis with dynamic US

PURPOSE: To evaluate the role of dynamic ultrasonography (US) in the diagnosis of bladder dysfunction and to compare dynamic US with urodynamic study, which is considered to be the standard in the diagnosis of bladder dysfunction. MATERIALS AND METHODS: Images from 71 pairs of examinations in 63 patients (median age, 7.9 years; range 1.0-17.4 years) were included in the study. After the child consumed adequate fluids in an appropriate environment, natural filling of the bladder occurred, and dynamic US was used to evaluate detrusor activity, determine capacity of the bladder, and estimate residual urine volume. A urodynamic study was performed in every patient within 6 months of dynamic US and under the same treatment conditions. The paired Student t test was used to compare the maximal cystometric capacity values obtained with the two examinations. Analysis of validity was performed with the calculation of sensitivity, specificity, positive and negative predictive values, and their respective 95% confidence limits. RESULTS: The bladder capacity was not significantly different between dynamic US and urodynamic study (P =.12). Analysis of validity for the determination of the presence of clinically substantial residual urine showed 97.7% sensitivity and 100% specificity for dynamic US. The sensitivity and specificity of dynamic US in the detection of involuntary detrusor contraction were 93.0% and 88.9%, respectively. In the analysis of involuntary detrusor contraction with urine leakage, dynamic US showed sensitivity of 100% and specificity of 97.8%. CONCLUSION: Dynamic US is a sensitive method for the diagnosis of bladder dysfunction.     

儿童管型肠重复畸形的影像学诊断

目的 探讨儿童管型肠重复畸形的影像特征。方法 研究分析６例经手术病理证实的儿童管型肠重复畸形的ＣＴ、超声及胃肠造影（ＧＩ）资料。结果 肠重复畸形囊肿ＣＴ检查５例均表现为单房、厚壁囊性肿块,囊壁可见“晕轮征”,其中２例与肠管交通者可见囊内含气征。囊肿均呈肠管状或“Ｕ”形走向。Ｂ超表现与ＣＴ所见类似：６例均呈囊性、长管状,类似内充液体的扩张肠管,管（囊）壁可见“双环圈征”,其中２例部分囊壁局限性增厚。     

Occult metastatic neck disease: detection with US and US-guided fine-needle aspiration cytology

The authors performed a prospective study of the value of ultrasonography (US) and US-guided fine-needle aspiration cytology (FNAC) for assessment of N0 lesions in the neck. Preoperative US was performed in 107 patients with squamous cell carcinoma of the head and neck, who underwent 132 elective neck dissections. During the US examination of the last 54 patients, who underwent 70 elective neck dissections, US-guided FNAC was performed. US alone was found to be an unreliable method for detecting occult lymph node metastasis; the accuracy never exceeded 70% (93 of 132), with a sensitivity of 60% (32 of 53) and a specificity of 77% (61 of 79). In contrast, US-guided FNAC had an accuracy of 89% (62 of 70), a sensitivity of 76% (25 of 33), and a specificity of 100% (37 of 37). Because of the high sensitivity and specificity of US-guided FNAC for the assessment of the N0 neck, this modality may play an important role in directing treatment of these patients in the future.