Advantages and disadvantages of three-dimensional computed tomography intraoperative localization for functional endoscopic sinus surgery.

Intraoperative three-dimensional computed tomography (3-D-CT) localization has been available for use during functional endoscopic sinus surgery (FESS) for several years, although relatively few otolaryngologists operate in conjunction with this technology. Proponents of intraoperative localization believe that operating with stereotaxis enhances surgical precision and reduces complications. A 1-year review was conducted at the University of Pennsylvania from January 1994 through January 1995. During this period 5% of sinus operations were performed in conjunction with intraoperative localization. The advantages and disadvantages of using intraoperative localization were evaluated for each case. Also examined were type and indication for surgery, anesthesia used, added time, and cost. Overall, intraoperative localization was found to be helpful when anatomy was distorted or obscured. However, selecting patients who may have benefited from localization was often not possible using preoperative data. Ideally, localization should be available for all FESS. Criteria are outlined which will need to be met prior to localization becoming a significant aspect of FESS.

Radiology faculty evaluation: bi-institutional implementation of an experimental appraisal instrument.

RATIONALE AND OBJECTIVES: The authors evaluated the reliability and validity of an experimental radiology faculty appraisal instrument. MATERIALS AND METHODS: Residents from the University of Wisconsin (UW) and Indiana University (IU) were asked to use a previously developed behaviorally based, 53-item experimental faculty appraisal instrument. Twenty UW residents evaluated 29 UW faculty members and 37 IU residents evaluated 31 IU faculty members by using the experimental instrument. Residents also evaluated faculty by using their institution's existing appraisal instrument. RESULTS: Correlations between existing and experimental forms were .69 and .87 for UW and IU, respectively. Existing form reliabilities were .89 and .94 and experimental form reliabilities were .98 and .98 for UW and IU, respectively. Experimental form length was reduced to 30 items by eliminating the questions that correlated the least with section scores. Reliabilities of scores on the shortened form were .97 and .98 and correlated .65 and .88 with scores on the longer form for UW and IU, respectively. CONCLUSION: Ratings obtained with the existing forms correlated substantially with the experimental form, attesting to the experimental form's validity. Shortening the experimental form had a minimal effect on the reliability and validity of the data obtained. The behavior-based form was used to rate behaviors that residents believed discriminated between effective and ineffective instructors, enabling an objective and relevant assessment to be made.

Development of a radiology faculty appraisal instrument by using critical incident interviewing.

RATIONALE AND OBJECTIVES: To develop a valid and reliable radiology faculty appraisal instrument based on scientific methods. MATERIALS AND METHODS: Fifteen radiology residents participated in critical incident interviewing. During a 1-hour interview, a resident was asked to describe five incidents each of effective and ineffective faculty behavior. Two investigators independently listened to the tape-recorded interviews, and two different investigators sorted the incidents into broad categories. A faculty appraisal instrument was developed by listing similar incidents under broad categories. A five-point rating scale was applied to each item. Content validity was assessed by resident and faculty critique of the appraisal instrument. RESULTS: A total of 168 incidents of faculty behavior were generated. The frequency with which similar incidents were reported was recorded. The most common behaviors reported were related to staff expertise and teaching. Interjudge reliability was good, as determined by computing K indices of agreement (overall K = 0.59). There was good agreement regarding instrument content validity among residents but not among faculty. CONCLUSION: Residents supported the use of the new appraisal instrument, but further tests of validity and reliability and faculty acceptance of the instrument will determine its usefulness as a tool for monitoring faculty teaching performance and making decisions regarding faculty promotion.

Breast imaging trends in Wisconsin.

UNLABELLED: This survey was performed to determine what breast imaging services are being offered in Wisconsin and compare this information to a similar survey performed in 1997 looking for any developing trends. METHODS: A survey of participants at the University of Wisconsin Mammography Update Continuing Education Conference of 1999 was performed. Of the 135 questionnaires distributed, 68 were returned fully completed and 2 partially completed. RESULTS: The majority of sites were located in Wisconsin with 59 diagnostic facilities and 57 screening facilities surveyed (some participants were involved with more than one facility). Overall there has been a marked increase in the number of sites having some type of women's imaging center and there has been an increase in the volume and type of breast interventions performed by medical imagers. CONCLUSION: Breast imaging and breast interventions are increasing rapidly with increased involvement of the medical imager in the diagnosis and management of breast disease.

Mammography facility trends across Wisconsin.

This paper summarizes the survey results obtained from the University of Wisconsin Mammography Update CME conference. This survey queried participants regarding the breast imaging services they offer. From 147 questionnaires distributed, 110 were returned. The majority of sites were in Wisconsin and were hospital based (57%). Thirty three percent were in clinic settings and 11 percent were "other" settings-clinics specializing in women's health and breast imaging. The survey addressed coordinated breast physical examinations, prior mammographic studies, self-referral, communication of mammographic results, patient call-backs for additional studies, breast compression, breast implants, scheduling, definitions of screening and diagnostic mammograms, presence of an on-site radiologist, and time allotted for the examinations. This survey attempted to gather useful information about the trends and practices of multiple diverse mammography facilities across Wisconsin and in surrounding states.

Sonographic artifacts and their origins.

Artifacts are encountered daily in clinical sonography. They may be observed in B-mode gray-scale imaging, spectral pulsed Doppler imaging, and color Doppler imaging. Most of these distortions can be understood at a basic level by an appreciation of the form of the focused sound beam, the interaction of sound with tissue, and assumptions made about the spatial assignment of reflected echoes. Sonographic systems assign depth based on the time interval of round-trip echo travel and assume a straight line and singular path from transducer to reflector and reflector to transducer. The same speed of sound is assumed in all tissues for the purposes of spatial assignment. Some inherent acoustic artifacts are used reflexively to characterize tissue. Strong acoustic enhancement behind an anechoic structure confirms the diagnosis of a cyst. Clean acoustic shadowing distal to an echogenic focus in the gallbladder leads us to the diagnosis of gallstones. If unrecognized, acoustic artifacts can cause serious misdiagnoses. Several commonly encountered artifacts are illustrated, with a basic physical explanation of their occurrence.

Utility of axillary views in postmastectomy patients.

This study was performed to determine the utility of routine axillary radiography in postmastectomy patients. The records of 185 postmastectomy patients who had undergone axillary radiography were retrospectively reviewed. Of 499 views obtained, only 10 (2%) were reported as abnormal. Only one of the 10 patients with abnormal studies had a demonstrated recurrence that corresponded to the mammographic finding. This patient also had positive physical examination results at that time. Eight of the 185 patients developed local recurrences, four of which were in the axilla of the affected side. These four cases were all detected at physical examination; two patients underwent relatively concurrent axillary radiography. One of these two patients with abnormal physical examination results had a positive axillary view obtained in the same month. The other of these two patients with abnormal physical examination results had a negative axillary view obtained 3 months earlier. The authors conclude that routine axillary radiography is not useful in postmastectomy patients.

Reversed or absent hepatic arterial diastolic flow in liver transplants shown by duplex sonography: a poor predictor of subsequent hepatic artery thrombosis.

OBJECTIVE: We studied the value of absent or reversed diastolic flow in the hepatic artery, shown by duplex sonography of recently transplanted livers, in predicting subsequent hepatic artery thrombosis. MATERIALS AND METHODS: We retrospectively reviewed the records of liver transplantations performed in adults during a 3-year period at our institution. Duplex Doppler studies were done within 24 hr after transplantation and subsequently reviewed. The clinical course of all patients with absent or reversed diastolic flow in the hepatic artery immediately after transplantation was evaluated. RESULTS: Of the 160 liver transplants included in this study, 30 had aberrant diastolic flow in the hepatic artery immediately after transplantation. Twenty had reversed flow, and 10 showed no flow in diastole. In this group of 30 transplants, complications developed in six; two were vascular in origin. One of these complications was thrombosis of the hepatic artery 12 months after transplantation. This 3% thrombosis rate is similar to the 4.6% thrombosis rate of the 130 patients who had antegrade diastolic flow in the hepatic artery immediately after transplantation. CONCLUSION: Reversed or absent diastolic flow in the hepatic artery of a recently transplanted liver has no correlation with subsequent hepatic artery thrombosis.

Spectral and color Doppler artifacts.

Artifacts in spectral and color Doppler imaging can be confusing and lead to misinterpretation of flow information. The authors review these artifacts by considering three main causes: inappropriate equipment settings, anatomic factors, and physical and technical limitations of the modality. Incorrect gain, wall-filter, or velocity scale settings can cause loss of clinically important information or distortion of the tracing. Reflection of the Doppler signal from highly reflective surfaces can create a color Doppler mirror image. Vascular motion can introduce artifactual variation in velocity as the sample volume passes through different velocities in a laminar flow state. Unintentional motion can cause a generalized Doppler shift. Increasing the angle of Doppler interrogation degrades the quality of the tracing and gives the impression of spectral broadening. As angulation approaches 90 degrees, directional ambiguity can occur, suggesting bidirectional flow. Grating and side lobes can interrogate areas unrelated to the sample volume and introduce extraneous Doppler information to the apparent area of interrogation. Recognition of these artifacts is essential to proper interpretation of Doppler information and rendering a correct diagnosis.

Invasive procedures in the female pelvis: value of transabdominal, endovaginal, and endorectal US guidance.

Transabdominal, endovaginal, and endorectal ultrasonographic (US) guidance is indispensable for a multitude of invasive procedures in the female pelvis. Transabdominal uterine US performed with a fluid-filled bladder is appropriate and convenient for guidance of difficult dilation and curettage procedures. Transabdominal intraoperative US can be employed to guide several procedures for which the more expensive intraoperative hysteroscopic procedure is now used. Aspiration of symptomatic ovarian cysts that appear benign at US with an endovaginally guided small-gauge needle is simple and effective. Simple noninfected pelvic fluid collections may be aspirated transvaginally for both diagnosis and therapy by using endovaginal guidance. Endovaginal US demonstrates the anatomic relationships of a pelvic abscess to adjacent structures, allowing safe access for transvaginal drainage. By using an endovaginal transducer with a needle guide, cervical and vaginal cuff masses may be easily sampled. An obstructed uterus may be accessed by puncturing obstructive tissue with a trocar-containing needle guided by an endorectal probe. US guidance for placement of a central brachytherapy tandem is performed via the abdominal approach after the bladder has been distended with sterile water. Endorectal US transducers may be effectively used to guide placement of interstitial brachytherapy needles in pelvic soft-tissue masses.

Urinary tract abnormalities in children with acute focal bacterial nephritis.

OBJECTIVE: To review the presentation, methods of diagnosis, and incidence of concomitant urological abnormalities in children with acute focal bacterial nephritis (AFBN, also known as lobar nephronia, a severe nonliquefactive infection involving one or more renal lobules). PATIENTS AND METHODS: Sixteen children (age range 6 months to 9 years) diagnosed with AFBN over a 5-year period were retrospectively reviewed. Their age, gender, presenting symptoms, presence of urinary tract abnormalities, radiological imaging and treatment were assessed. RESULTS: All 16 children received intensive intravenous and oral antibiotics. Ten required intervention for predisposing conditions including vesico-ureteric reflux (four), bladder diverticulum (one), renal and peri-rectal abscess (two), ureteric or bladder calculi (two), and renal mass (one). In addition, three children had reflux not requiring surgery; one had multiple renal calyceal diverticula, one had Hinman syndrome and one had leukaemia. CONCLUSION: Acute focal bacterial nephritis is being diagnosed with increasing frequency through increasing awareness and advances in imaging modalities. Active urological evaluation is warranted because of the high incidence of urinary tract abnormalities. In addition to antibiotics, intervention was needed in most children in this series.

Mammographic evaluation of the postsurgical and irradiated breast.

Mammography is important in women who elect lumpectomy and radiation therapy for breast carcinoma: to record the preoperative state, to assess the completeness of resection, and to detect recurrences and second primaries. Mammography of these patients, however, is difficult since surgery and irradiation may cause changes simulating carcinoma. This article describes the findings in the postsurgical and irradiated breast and the difficulty of differentiating the changes from recurrent carcinoma. It also illustrates the findings in recurrences and second primaries.

Current status of small-bowel ultrasound.

Ultrasonography offers direct imaging of the bowel wall and allows dynamic evaluation of peristalsis. It helps to differentiate eosinophilic gastroenteritis from regional enteritis and lymphoma, displays a typical appearance in intussusception and is quite specific in the afferent loop syndrome, closed-loop obstruction and lymphedema. It may be helpful in ischemia of the bowel and in the evaluation of acute appendicitis.

Inflammatory aortic aneurysm (periaortic fibrosis): radiologic imaging.

Inflammatory aneurysms represent a distinct surgical entity with a reported incidence varying from 5% to 23% of all abdominal aortic aneurysms. Surgical repair of inflammatory aneurysms is associated with a higher morbidity and mortality than is repair of simple aortic aneurysms. Complicated cases require suprarenal aortic control, and the surgeon must be forewarned to maximize the chance for successful aneurysm repair. Preoperative diagnosis of this entity by cross-sectional imaging facilitates improved planning of the operative approach and permits the institution of preoperative steroid treatment to reduce the volume of the periaortic fibrotic mass. Ultrasound demonstrates the inflammatory process as a hypoechoic mass surrounding the intensely echogenic, thickened aortic wall. Computed tomography reveals a thickened, often calcified aortic wall and a mass of periaortic inflammatory tissue. Dynamic scanning reveals rapid intraluminal enhancement, slightly delayed enhancement of the inflammatory mass, and nonenhancement of the thick fibrous adventitia.

Value of transperineal sonography in the assessment of vaginal atresia.

We studied the value of transperineal sonography in the preoperative assessment of seven patients with clinically suspected vaginal atresia. Although transabdominal scanning is useful to determine if hydrocolpos or hydrometrocolpos is present, this method does not allow measurement of the thickness of a caudally placed obstructive septum. This information is useful in planning reconstructive surgery. All seven patients had transabdominal sonography, with five showing a low-lying obstruction. In those five patients, the distance between the perineal surface and the caudal aspect of the distended vagina, measured with electronic calipers on the transperineal sonograms, ranged from 1.0 to 4.0 cm. We conclude that when vaginal atresia is clinically suspected, transabdominal sonography should be performed to confirm the diagnosis. When a low-lying obstruction is identified, transperineal sonography should be performed to determine the length of the obstructive segment.

The underuse of women's health care services in hungary. A preliminary study.

In order to collect baseline data for a 2-year Women's Health Program in Hungary, a survey was conducted of 369 women residing in one community setting. The purpose of this descriptive exploratory study was to gather preliminary data that would help identify perceptions of inhibitors to utilization of women's health services. An additional purpose was to identify perceived health needs in the study setting and to make recommendations for changes in the existing services. The survey results indicated that women were satisfied overall with their health care. Equivocal responses suggested, however, that patient-provider interactions and lack of understanding regarding preventive health care may contribute to the underuse of services. The authors suggest that public feedback that includes women's opinions and perceived needs is essential in health program planning and evaluation. In order to accomplish this, standardized Hungary-specific research instruments must be developed.

Use of flexible fiberoptic endoscopy for determination of endotracheal tube position in the pediatric patient.

Flexible fiberoptic endoscopy (FFE) was utilized in a series of 24 critically ill pediatric patients to determine the position of the endotracheal tube (ETT) tip relative to the carina. Training on a model system revealed no significant differences in predicting ETT-to-carina distance (ETT-C) with respect to operator, ETT size, or absolute ETT-C as measured directly. No significant differences in ETT-C could be determined between traditional bedside chest x-ray (CXR) or FFE when FFE was performed on intubated pediatric ICU patients. A correlation coefficient comparing the two methods was 0.767. Neither ETT size nor FFE operator affected this correlation. Although used as the gold standard, CXR failed to demonstrate the carina clearly in 15 patients. FFE delineated the carina clearly in 22 patients. Ability to visualize ETT placement within the trachea was essentially identical for FFE (22/24) compared to CXR (23/24). However, the time required to obtain this information was significantly different: 30.6 min (range 13 to 57) for CXR; 40 sec (range 16 to 94) for FFE. No clinically significant changes in patient pulse oximetry, heart rate, or physical exam were observed during FFE. Only copious secretions impaired the utility of FFE. We concluded that FFE is a safe, fast, easily learned method to determine relative ETT position or precise ETT-C in the mechanically ventilated pediatric patient.

Conventional color Doppler velocity sonography versus color Doppler energy sonography for the diagnosis of acute experimental torsion of the spermatic cord.

OBJECTIVE: We compared color Doppler velocity sonography and color Doppler energy sonography for the diagnosis of spermatic cord torsion in a canine model and determined the degree of torsion necessary to acutely halt testicular blood flow. MATERIALS AND METHODS: Spermatic cord torsion was created in five dogs by exposing and rotating the ipsilateral testis 0 degree, 180 degrees, 270 degrees, 360 degrees, 450 degrees, and 540 degrees. Detorsion followed. The testicles were scanned at each torsion stop using both color Doppler velocity sonography and color Doppler energy sonography. Doppler parameters were optimized (by phantom and test scans) and maintained at a tolerable noise level throughout the experiment. Readers who were unaware of the degree of torsion compared flow in the rotated and contralateral control testes. RESULTS: Flow became undetectable by color Doppler velocity sonography and color Doppler energy sonography at 450 degrees in four of five cases and at 540 degrees in one of five cases. We found no significant difference between the velocity and the energy techniques for detecting this absence of flow (p > .05, Wilcoxon test). We found a significant difference in degree of flow for both techniques when comparing controls and all degrees of torsion combined (p < .006, Mann-Whitney test), but significance was achieved at lesser degrees of torsion with the velocity technique than with the energy technique (180 degrees and 360 degrees, respectively, Wilcoxon test). CONCLUSION: Color Doppler energy sonography was not significantly more sensitive than color Doppler velocity sonography for the diagnosis of spermatic cord torsion in this model. Complete occlusion of arterial inflow occurred at 450-540 degrees of torsion.