Ronald O. Bude

Imaging of the Placenta: A Multimodality Pictorial Review

The placenta is often overlooked in the routine evaluation of a normal gestation, receiving attention only when an abnormality is detected. Although uncommon, abnormalities of the placenta are important to recognize owing to the potential for maternal and fetal morbidity and mortality. Pathologic conditions of the placenta include placental causes of hemorrhage, gestational trophoblastic disease, retained products of conception, nontrophoblastic placental tumors, metastases, and cystic lesions. Sonography remains the imaging modality of choice for evaluation of the placenta. Magnetic resonance (MR) imaging can be of added diagnostic value when further characterization is required, particularly in the setting of invasive placental processes such as placenta accreta and gestational trophoblastic disease. Computed tomography (CT) has a limited role in the evaluation of placental disease owing to limited tissue characterization, compared with that of MR imaging, and the radiation risk to the fetus; this risk often outweighs the benefit. The primary role for CT is in the evaluation of trauma and gestational trophoblastic disease, for which it allows characterization of the primary lesion and distant metastases.

Laparoscopic injury of abdominal wall blood vessels: A report of three cases

Background:Operative laparoscopy is being used for an increasing number of applications. Many of these innovative techniques require the insertion of large trocars through the anterior abdominal wall at points lateral to the midline. Because of the rich vascular supply of the anterior abdominal wall

Cross-Sectional Imaging of Acute and Chronic Gallbladder Inflammatory Disease

OBJECTIVE The purpose of this article is to provide a comprehensive review of the clinical and cross-sectional imaging features of a variety of acute and chronic gallbladder inflammatory diseases. CONCLUSION Inflammatory gallbladder diseases are a common source of abdominal pain and cause considerable morbidity and mortality. Although acute uncomplicated cholecystitis and chronic cholecystitis are frequently encountered, numerous other gallbladder inflammatory conditions may also occur that can be readily diagnosed by cross-sectional imaging.

The location of abdominal wall blood vessels in relationship to abdominal landmarks apparent at laparoscopy

OBJECTIVE Our purpose was to evaluate the location of the major blood vessels of the abdominal wall relative to landmarks apparent at laparoscopy. STUDY DESIGN Abdominal computed tomographic images of 21 reproductive-aged women at an academic center were retrospectively reviewed to determine the location of the inferior epigastric, superficial epigastric, and superficial circumflex iliac arteries and the lateral rectus muscle margins in relation to the symphysis pubis, the umbilicus, and the abdominal midline. These locations were correlated with each other and with body mass index using Pearsons correlation coefficient. RESULTS Above the symphysis the inferior and superficial epigastric arteries were 5.6 +/- 1.0 cm (mean +/- SD) and 5.5 +/- 2.0 cm from the midline, respectively. Although the location of these two vessels correlated (r = 0.6, p = 0.02), the mean difference in their location was 1.4 +/- 1.1 cm. Near the level of the umbilicus the superficial epigastric and circumflex iliac arteries and the lateral rectus muscle margin were 4.6 +/- 1.4 cm, 10.7 +/- 1.7 cm, and 7.6 +/- 1.5 from the midline, respectively. Only the lateral rectus muscle margin correlated with body mass index (r = 0.65, p = 0.004). CONCLUSION When laparoscopic landmarks are not visible to guide placement, lateral trocars should be placed approximately 8 cm from the midline and at least 5 cm above the symphysis to minimize the risk of vessel injury.

Sonographic Twinkling Artifact for Renal Calculus Detection: Correlation with CT

PURPOSE To retrospectively correlate sonographic color Doppler twinkling artifact within the kidneys with unenhanced computed tomography (CT) in the detection of nephrolithiasis. MATERIALS AND METHODS Institutional review board approval was obtained for this retrospective HIPAA-complaint investigation, and the informed consent requirement was waived. Sonographic imaging reports describing the presence of renal twinkling artifact between January 2008 and September 2009 were identified. Subjects who did not undergo unenhanced abdominal CT within 2 weeks after sonography were excluded. Ultrasound examinations were reviewed by three radiologists working together, and presence, number, location, and size of renal twinkling artifacts were documented by consensus opinion. Sonographic findings were correlated with unenhanced CT (5-mm section width, no overlap) for nephrolithiasis and other causes of twinkling artifact. The number, location, and size of renal calculi at CT were documented. RESULTS The presence of sonographic renal twinkling artifact, in general, had a 78% (95% confidence interval: 0.66, 0.90) positive predictive value for nephrolithiasis anywhere in the kidneys at CT. The true-positive rate of twinkling artifact for confirmed calculi at CT was 49% (73 of 148 twinkling foci), while the false-positive rate was 51% (75 of 148 twinkling foci). The overall sensitivity of twinkling artifact for the detection of specific individual renal calculi observed at CT was 55% (95% confidence interval: 0.47, 0.64). CONCLUSION While renal twinkling artifact is commonly associated with nephrolithiasis, this finding is relatively insensitive in routine clinical practice and has a high false-positive rate when 5-mm unenhanced CT images are used as the reference standard. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11102128/-/DC1.

Imaging of joints with laser‐based photoacoustic tomography: An animal study

Photoacoustic tomography (PAT), a nonionizing, noninvasive, laser-based technology was adapted to joint imaging for the first time. Pulsed laser light in the near-infrared region was directed toward a joint with resultant ultrasonic signals recorded and used to reconstruct images that present the optical properties in subsurface joint tissues. The feasibility of this joint imaging system was validated on a Sprague Dawley rat tail model and verified through comparison with histology. With sufficient penetration depth, PAT realized tomographic imaging of a joint as a whole organ noninvasively. Based on the optical contrast, various intra- and extra-articular tissues, including skin, fat, muscle, blood vessels, synovium and bone, were presented successfully in images with satisfactory spatial resolution that was primarily limited by the bandwidth of detected photoacoustic signals rather than optical diffusion as occurs in traditional optical imaging. PAT, with its intrinsic advantages, may provide a unique opportunity to enable the early diagnosis of inflammatory joint disorders, e.g., rheumatoid arthritis, and to monitor therapeutic outcomes with high sensitivity and accuracy.

Comparison Between Color Doppler Twinkling Artifact and Acoustic Shadowing for Renal Calculus Detection: An In Vitro Study

To assess the ability of the color Doppler twinkling artifact to detect renal stones relative to acoustic shadowing, we scanned seven uric acid calculi embedded in a tissue mimicking phantom and in sheep kidneys using a high frequency linear array and a standard curved linear array ultrasound scanheads (L12-5 and C5-2; Philips Ultrasound, Bothel, WA, USA). The stones were scanned in and out of focus. The scans were optimized for shadow formation in gray-scale imaging and for color twinkling in color Doppler imaging. The images were analyzed using Image J (http://rsb.info.nih.gov/ij/). We calculated the contrast to noise ratios (C/N) for the acoustic shadows and the color twinkling artifact compared with background. These measurements were then evaluated using a single factor analysis of variance (ANOVA) and paired two-tailed t tests. With these comparisons, the C/Ns for twinkling were significantly higher than for acoustic shadowing. On average, twinkling produced 19.2 dB greater C/Ns for stones in the phantom and 17.6 dB more for the stones in the kidneys. In addition, ANOVA showed that twinkling is resistant to focusing and scanning frequency differences. The results suggest that the twinkling artifact is a robust method for detecting the presence of renal calculi. The color signature is easier to detect than is acoustic shadowing. Twinkling may be relatively resistant to many of the problems that plague ultrasound examinations for renal stones, i.e., out-of-focus scans that might be caused by beam aberration effects due to patient body habitus.

Technique and diagnostic utility of saline infusion sonohysterography

The introduction of saline infusion sonohysterography has significantly improved sonographic diagnosis of various endometrial pathologies. This procedure entails instillation of warm saline into the uterine cavity transcervically to provide enhanced visualization of the endometrium during transvaginal ultrasound examination. This article reviews the sonohysterography technique and current utility, as well as the spectrum of imaging features of various endometrial pathologies.

Effect of furosemide and intravenous normal saline fluid load upon the renal resistive index in nonobstructed kidneys in children

Recent literature has shown that relative to baseline the renal resistive index remains unchanged in nonobstructed kidneys and increases in obstructed kidneys after administration of furosemide. To our knowledge the effect upon the renal resistive index of furosemide administered in conjunction with intravenous normal saline fluid load has not been reported. We evaluated the renal resistive index in 13 nonobstructed kidneys in 8 children 6 to 18 years old before and after furosemide and intravenous normal saline fluid load. The mean resistive index decreased from baseline (mean decrease was 0.06 +/- 0.06 standard deviation), with the observation of a resistive index decrease significant to p < 0.005). It appears likely that the combination of an intravenous normal saline fluid load and furosemide caused the resistive index decrease, since a decrease was not observed with furosemide alone; however, these results cannot exclude the possibility that the resistive index decrease was due to the intravenous normal saline fluid load alone. Nonetheless, these data are important since they may provide the foundation for the development of a pharmacologically challenged Doppler sonographic examination using furosemide and intravenous normal saline fluid load to evaluate better potentially obstructed kidneys.

Prevalence of Malignancy in Thyroid Nodules with an Initial Nondiagnostic Result After Ultrasound Guided Fine Needle Aspiration

The objective of this study was to determine the rate of malignancy in thyroid nodules with an initial nondiagnostic fine needle aspiration. From October 2001 to April 2007, biopsies were performed on 1344 thyroid nodules in our practice. Biopsies were performed on nodules using 25-27 gauge needles, ultrasound guidance and multiple passes using both suction and capillary action. We retrospectively reviewed the results of these biopsies as well as any further management of nodules that received nondiagnostic results (IRB HUM00006459). Following initial biopsy, 295/1344 (21.9%) of nodules received nondiagnostic pathologic results. Of this population, 39 nodules (13.1%) were lost to follow-up. Of the remaining 256 nodules that received a repeat FNA, surgical excision, or greater than 24 months of clinical and imaging follow-up, only five cancers were detected, representing only 2% of the population that received an initial nondiagnostic biopsy result. All of these cancers were papillary neoplasms. When rigorous, ultrasound-guided, fine needle aspiration of thyroid nodules is performed, a nondiagnostic histopathologic result should not be interpreted as suspicious for thyroid cancer. Given the low rate of malignancy in this population (2%), we suggest that clinical and imaging follow-up of these nodules, opposed to repeat sampling, is warranted.