Biomedical subjects
Publications and source records attributed to Shweta Bhatt.
Ultrasonography and CT have allowed improved detection of renal mass lesions. Though ultrasonography is less sensitive in the characterization of the renal mass lesions, it is often the first imaging modality for evacuation of the kidneys. This article gives an overview of the benign and malignant renal mass lesions and the role of ultrasonography in their characterization.
With increasing technologic advances in ultrasound, its applications have continued to grow for the detection of pathology and physiology. To avoid misinterpretation of results, however, the Doppler US practitioner must understand the factors that produce a Doppler signal, whether vascular, motion, or artifact. Color or power Doppler artifacts can be verified by their atypical spectral waveform. Some artifacts, such as aliasing (for rapid detection of stenoses or arteriovenous fistulae) and the twinkle artifact (for identification of renal calculi and verification of other stones or crystals), are extremely useful diagnostically. Careful attention to the technical parameters of frequency, gain, filter and scale is required to correctly identify vascular patency or thrombosis, especially in slow-flowing vessels.
Ultrasound plays an important role and adds essential information in diagnosing benign intrascrotal lesions. Characterization of benign intrascrotal lesions with sonography, in combination with clinical assessment, can lead to nonsurgical management or testicular sparing surgery. We present important sonographic features of benign intrascrotal lesions, including extratesticular lesions: adenomatoid tumors, papillary cystadenomas, spermatoceles, hydroceles, varicoceles, hernias; and intratesticular lesions: tunica albuginea cysts, testicular simple cysts, epidermoid cysts, tubular ectasia of the rete testis, intratesticular varicoceles, adrenal rest tumors, and splenogonadal fusion. The goal of this review is to provide the radiologist with a better understanding of benign lesions that occur in the scrotum.
Endometriosis is the presence of functional endometrial tissue outside the uterine cavity and the myometrium. It is an important cause of infertility and pelvic pain in women older than 25 years. Endometriomas are relatively common and can mimic other adnexal masses, and ultrasonography is often the first choice of imaging. This pictorial essay presents the sonographic appearance of endometriomas and similar-appearing adnexal masses and their characteristics, which may aid in their differentiation on routine ultrasonographic examination.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Multidetector row CT is the most recent advance in CT technology. An increased number of detector rows and more powerful x-ray tubes result in faster scanning time, increased volume coverage, and improved spatial and temporal resolution. MDCT technology allows superior image quality, decreased examination time, and the ability to perform complex multiphase vascular and three-dimensional examinations.
OBJECTIVE: The purpose of this presentation is to illustrate the normal sonographic anatomy of the penis and various imaging manifestations of penile trauma. METHODS: Penile trauma cases were collected and reviewed retrospectively from our archive. RESULTS: The normal sonographic anatomy of the penis and various pathologic conditions of patients with penile trauma are discussed. CONCLUSIONS: Sonography (especially with color Doppler sonography) is a useful imaging method for evaluating penile anatomy and various pathologic features in patients with penile trauma.
First trimester bleeding is a common presentation in the emergency room. Ultrasound evaluation of patients with first trimester bleeding is the mainstay of the examination. The important causes of first trimester bleeding include spontaneous abortion, ectopic pregnancy, and gestational trophoblastic disease; 50% to 70% of spontaneous abortions are due to genetic abnormalities. In normal pregnancy, the serum beta hCG doubles or increases by at least 66% in 48 hours. The intrauterine GS should be visualized by TVUS with beta hCG levels between 1000 to 2000 mIU/mL IRP. Visualization of the yolk sac within the gestational sac is definitive evidence of intrauterine pregnancy. Embryonic cardiac activity can be identified with CRL of >5 mm. A GS with a mean sac diameter (MSD) of 8 mm or more without a yolk sac and a GS with an MSD of 16 mm or more without an embryo, are important predictors of a nonviable gestation. A GS with a mean sac diameter of 16 mm or more (TVUS) without an embryo is a sonographic sign of anembryonic gestation. A difference of <5 mm between the mean sac diameter and the CRL carries an 80% risk of spontaneous abortion. Approximately 20% of women with first trimester bleeding have a subchorionic hematoma. The presence of an extra ovarian adnexal mass is the most common sonographic finding in ectopic pregnancy. Other findings include the tubal ring sign and hemorrhage. About 26% of ectopic pregnancies have normal pelvic sonograms on TVUS. Complete hydatidiform mole presents with a complex intrauterine mass with multiple anechoic areas of varying sizes (Snowstorm appearance). Twenty-five percent to 65% of molar pregnancies have associated theca-leutin cysts. Arteriovenous malformation of the uterus is a rare but life-threatening cause of vaginal bleeding in the first trimester. The sonographic findings in a patient with first trimester bleeding should be correlated with serum beta hCG levels to arrive at an appropriate clinical diagnosis.
The ability of US to diagnose the pathogenesis of the acute scrotum is unsurpassed by any other imaging modality. It is the first imaging performed in patients with acute scrotum. Knowledge of the normal and pathologic sonographic appearance of the scrotum and proper sonographic technique is essential for accurate diagnosis of acute scrotum. High-frequency transducer sonography combined with color flow Doppler sonography provides the information essential to reach a specific diagnosis in patients with testicular torsion, epididymo-orchitis, and testicular trauma.
Vaginal bleeding is a leading cause of presentation for emergency care during the first trimester of the pregnancy. Clinical assessment of the pregnancy outcome at this stage is less reliable. US examination is crucial in establishing IUP and early pregnancy failure and to exclude other causes of bleeding, such as ectopic pregnancy and molar pregnancy. Diagnosis of a normal IUP at this stage not only assists the physician in an expectant management, but also gives a psychologic boost to the patient. With recent advances in US technology and the availability of high-frequency transvaginal transducers, reliable diagnosis of early pregnancy failure can be made even before the embryo is visible.
This study was conducted to demonstrate the feasibility of high intensity focused ultrasound (HIFU) application to control post-liver-biopsy hemorrhage. Anesthetized Yorkshire pigs (n = 3; mean weight = 23.0 kg) were used and the liver organ was exposed surgically by an open laparotomy. Core biopsies were performed on the hepatic parenchyma with 14-gauge (n = 41) and 18-gauge (n = 33) core biopsy needles. The focus of HIFU (4.23 MHz) field was applied for 15 to 45 s to the needle entry site in the liver immediately after needle retraction. Blood loss from a biopsy site was determined using surgical sponges as absorbent applied at the site. Mean blood loss for control sites was 6.16 g (14-gauge, n = 20) and 1.22 g (18-gauge, n = 10). Virtually no blood loss was measured for biopsies after HIFU application (n = 44) for using needles of both sizes. Our results indicate that intraoperative HIFU application could successfully induce hemostasis after liver biopsy in a porcine model.
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OBJECTIVE: To illustrate how spectral Doppler waveform analysis plays an adjunctive but very definite role in scrotal sonography. METHODS: The cases illustrate a variety of testicular disorders that were collected at a referral tertiary care center. RESULTS: Normal and a variety of pathologic conditions of the testes are discussed, along with their signature spectral waveforms. CONCLUSIONS: Analysis of the spectral waveform provides important additional information in various scrotal disorders with acute pain. Spectral waveform analysis is critical to diagnosing incomplete torsion when color and power Doppler examinations are indeterminate.