Dawna J. Kramer

Quantitative analysis of respiratory, motor, and sensory function after supraclavicular block

The incidence and clinical significance of hemidiaphragmatic paresis after supraclavicular block of the brachial plexus is unknown.Eight healthy volunteers received a supraclavicular block with a standard technique using 30 mL of 1.5% lidocaine. Respiratory function was assessed with ultrasound of the diaphragm, respiratory inductive plethysmography (RIP), and pulmonary function tests (PFT) every 20 min. Sensory block was assessed with pinprick and motor block with isometric force dynamometry every 20 min. Four of eight subjects demonstrated hemidiaphragmatic paresis on both ultrasound and RIP. No subject experienced changes in PFT values or subjective symptoms of respiratory difficulty. Motor and sensory blockade outlasted hemidiaphragmatic paresis. These results are contrasted to the often symptomatic, 100% incidence of hemidiaphragmatic paresis seen after interscalene block. In this study of healthy volunteers, supraclavicular block was associated with a 50% incidence (95% confidence interval 14-86) of hemidiaphragmatic paresis that was not accompanied by clinical evidence of respiratory compromise. Implications: Interscalene block is always associated with diaphragmatic paralysis and respiratory compromise. The significance of these side effects after supraclavicular block is unknown. Using sensitive measures of respiratory function, we determined that diaphragmatic paralysis occurs less often with the supraclavicular approach and is not associated with respiratory difficulties in healthy subjects. (Anesth Analg 1998;86:1239-44)

Applications of musculoskeletal sonography.

To successfully examine the musculoskeletal system sonographically, one must understand the normal musculoskeletal anatomy and function and be aware of the abnormal processes that affect the musculoskeletal structures. The goal of this review article is to provide a systematic approach to sonographic examination of the musculoskeletal system. The general sonographic appearances of normal and abnormal muscles, tendons, ligaments, bursae, and nerves are reviewed. The article then applies this general information to specific clinical applications by reviewing the normal anatomy of and specific pathologic conditions that affect the shoulder, elbow, hand, wrist, hip, knee, ankle, and foot.

High detection rate of breast ductal carcinoma in situ calcifications on mammographically directed high-resolution sonography.

To assess the high‐frequency sonographic characteristics of ductal carcinoma in situ of the breast.

Intraoperative ultrasound guidance for intrauterine endoscopic surgery

Intraoperative US guidance for intrauterine endoscopic procedures appears to offer a noninvasive means of assessing the precision and adequacy of resectoscopic myomectomy and to provide the exact location of the instruments within the uterine cavity and uterine wall. A combination of intrauterine endoscopic procedures and intraoperative US guidance provides an accurate method to guide resectoscopic myomectomies and endometrial resection and to prevent inadvertent uterine perforation. Intraoperative imaging may have an application for other intrauterine endoscopic procedures and may preclude the need for simultaneous laparoscopy.

Systematic approach to difficult problems in breast sonography.

Although there is an increasing use of more imaging modalities in breast imaging, the role of breast sonography has not diminished-in fact, the applications of sonography have increased with the improvement of high-frequency equipment. Compared with other breast imaging modalities, current sonographic equipment has excellent spatial resolution and outstanding image contrast. Furthermore, sonography does not have the disadvantages of other modalities such as magnetic resonance imaging including exposure to intravenous contrast, higher expense, patient claustrophobia, and potential adverse contrast reaction or renal damage. The primary disadvantage of sonography is that this technique is highly operator dependent, particularly in the breast. However, if one can overcome the barrier of operator dependence, then one potentially may reduce the cost of diagnosis of breast cancers. Although many articles review sonographic appearances of solid neoplastic breast masses, relatively little attention has been directed toward subtle or confusing clinical and sonographic findings of breast cancer. This review defines methods to sonographically approach identifying vague mammographic and subtle magnetic resonance imaging lesions. Furthermore, because sonography is operator dependent, this article also involves discussing some of the pitfalls of breast sonography and how to avoid them.

Ultrasonographic stress testing of ulnar collateral ligament injuries of the thumb.

We compared ultrasonographic stress test evaluation to clinical examination of ulnar collateral ligament injuries to the thumb. The results of the sonographic and clinical examinations were compared to either operative findings or clinical follow‐up results if conservative treatment was elected. Of 25 patients, the clinical grade injury was identified correctly in 25 with ultrasonography compared to 24 with clinical examination. Of the grade III tears, ultrasonography missed two patients with Stener tears and physical examination misidentified or missed four patients with Stener tears. These results confirm the experience of others that ultrasonography is a useful method to evaluate injury to the ulnar collateral ligament of the thumb.

A Quality Improvement Initiative to Reduce Unnecessary Follow- up Imaging for Adnexal Lesions

Our objective was to improve the quality of pelvic ultrasound reports and decrease the number of physiologic and benign adnexal lesions unnecessarily referred for follow-up. We performed a prospective cohort study of 2 quality improvement interventions: academic detailing with education for the ultrasound radiologists and sonographers, and implementation of a national consensus guideline on adnexal cysts. Our primary quality outcome measure was the proportion of pelvic ultrasound exams in which follow-up was recommended for an adnexal lesion. Baseline data collection in January 2006 identified 252 pelvic ultrasound exams, of which 58 (23%) reported an adnexal lesion and 31 (12%) recommended follow-up. Retrospective review revealed that 17 of 31 (55%) reported adnexal lesions with follow-up recommended were physiologic or benign. After intervention 1, 59 of 214 (28%) pelvic ultrasound exams from January 2008 reported an adnexal lesion, with 18 (8%) recommending follow-up. After intervention 2, 64 of 296 (22%) pelvic ultrasound exams from January 2011 reported an adnexal lesion, with 16 (5%) recommending follow-up. Follow-up recommendations decreased 58% (12% versus 5%, P = .004), with significant increase in the proportion characterized as physiologic or benign (P = .001). Through a quality initiative aimed at appropriate description and follow-up recommendations for adnexal cystic lesions identified at ultrasound, we effectively reduced unnecessary imaging referrals. We conclude that: (1) acceptance of an expert consensus guideline was important to add credibility, (2) accessible image-rich charts are invaluable tools at point of use, and (3) elimination of some unnecessary imaging is under the control of the radiologist.

Amniotic fluid volume: fluid dynamics and measurement technique

Evaluation of amniotic fluid volume is an important aspect of obstetrical ultrasound. Several methods are currently used to describe amniotic fluid volumes. The most common are the subjective assessment of fluid and the semiquantitative methods. The reproducibility of these methods is excellent in experienced hands. Because of the multiple methods used to assess fluid, both oligohydramnios and polyhydramnios have numerous definitions. Regardless of which definition is used, it is clear that both of these entities are associated with a variety of fetal and maternal conditions. Abnormal amniotic fluid volume may be the only or earliest sonographic sign of an obstetrical problem. Therefore, it is important that sonologists are familiar with amniotic fluid volume assessment. Although subjective and semiquantitative techniques may produce similar results, a numerical scale is no substitute for experience and training. One should be able to recognize lesser degrees of fluid abnormality and be able to assess the trend of amniotic fluid volume in serial examinations.

Evaluation of Fetal Hands With Ultrasound During a Routine Obstetric Examination

In this prospective study, 100 second trimester fetuses were assessed to determine the frequency of visualization of the open fetal hands and the three phalanges of the fifth digit during a routine ultrasound examination. Open right hands were seen in 82 (82%) fetuses, and the three phalanges of the right fifth digit were seen in 71 (71%) fetuses. Open left hands were visualized in 80 (80%) fetuses, and the three phalanges of the left fifth digit were seen in 70 (70%) fetuses. Both open hands were seen in 73 (73%) fetuses, and only one open hand was seen in 17 (17%) fetuses. Fetal abnormalities, such as clenched hands with or without overriding fingers, hypoplasia of the middle phalanx of the fifth digit, or clinodactyly of the fifth finger, have been reported to be associated findings of certain fetal chromosomal disorders (e.g., trisomies 13, 18, and 21) and may initiate further genetic evaluation. The present study shows that it is feasible to include the assessment and documentation of fetal hands in the routine obstetric ultrasound examination without significantly increasing the scanning time.

Applications of Ultrasound of the Rectum and Anus

Ultrasound has many useful applications in the rectum and anus. The application most extensively studied and used is local staging of rectal tumors. Ultrasound can correctly identify the depth of neoplastic penetration in 80–85% of cases. The main weakness of ultrasound in staging rectal tumors is its tendency to overstage tumor depth. This overstaging is generally due to inflammation and fibrosis associated with the tumor. Even with its tendency to overstage. ultrasound is more accurate in staging the local tumor than is digital examination or computed tomography. Apart from its use in staging rectal tumors, ultrasound is also useful in imaging the anal sphincters. This application has been helpful in identifying causes of fecal incontinence. Ultrasound provides an objective method of documenting the anatomic anal sphincter abnormalities and measuring physiologic weakness in the puborectalis muscle. The traditional methods of manometry, electromyography, and defecography have many disadvantages. Ultrasounds general advantage over all these techniques is that it is less expensive. Furthermore, ultrasound is less painful than electromyography and, unlike defecography, does not involve use of ionizing radiation.