Time to go wireless? A 15-year single institution experience of radioisotope occult lesion localisation (ROLL) for impalpable breast lesions.

INTRODUCTION: Wire guided localisation (WGL) is the standard localisation technique for impalpable breast lesions. Radio-guided occult lesion localisation (ROLL) has been proposed as an alternative. We have been performing ROLL for therapeutic wide local excisions (WLE) and diagnostic excision biopsies (DEB) for the last 15 years. We present the largest reported consecutive series of ROLL excisions to date. PATIENTS AND METHODS: One thousand thirty nine consecutive patients who underwent ROLL for impalpable breast lesions were identified from a prospectively collected database. 673 patients underwent WLE and 366 patients underwent DEB. Data were analysed from proformas completed at the time of the procedure by the radiologist and operating surgeon. These data were supplemented with an analysis of patient electronic records including specimen radiograph and histopathology reports. RESULTS: 99.1% of ROLL WLE revealed histological diagnoses of invasive cancer or DCIS. 98.7% of radiological abnormalities were identified on WLE post-excision radiographs (97.5% following DEB). Complete excision was recorded in 79.0% of the WLE patients following histological evaluation. 31.7% of DEB cases were pathologically upgraded to a malignant diagnosis. The presence of microcalcification, preoperative underestimation of the lesion size and symptomatic referral predisposed to incomplete excision status. DISCUSSION: ROLL is a safe and effective technique to localise impalpable breast lesions. In addition ROLL has potential technical and logistic advantages over WGL.

An exact surface-integral approach for accurate interferometric microscopy of single nanoparticles.

We present a half-plane surface-integral equation (SIE) approach for modeling the optical phase response of a single nanowire under phase-stepping interferometric (PSI) microscopy. This approach calculates scattered fields exactly from the Helmholtz equation in this 2D problem, obviating the need for ray-optic approximations. It is demonstrated that refractive index metrology is enabled by this method, with precision as low as 7 × 10(-5) possible for current state-of-the-art PSI microscopes. For nanowires of known refractive index, radii as small as 0.001λ are shown to yield a measurable phase signal and are therefore potentially measurable by this approach. Measurements are also demonstrated to be relatively insensitive to the spectral and coherence characteristics of the light source, the illumination conditions, and variations in nanowire cross-section shape. Prospects for measuring both the radius and refractive index simultaneously, and scope for generalizing this approach to arbitrary nanoparticle shapes are discussed.

Improving the accuracy of self-assessment of practical clinical skills using video feedback--the importance of including benchmarks.

INTRODUCTION: Isolated video recording has not been demonstrated to improve self-assessment accuracy. This study examines if the inclusion of a defined standard benchmark performance in association with video feedback of a student's own performance improves the accuracy of student self-assessment of clinical skills. METHODS: Final year medical students were video recorded performing a standardised suturing task in a simulated environment. After the exercise, the students self-assessed their performance using global rating scales (GRSs). An identical self-assessment process was repeated following video review of their performance. Students were then shown a video-recorded 'benchmark performance', which was specifically developed for the study. This demonstrated the competency levels required to score full marks (30 points). A further self-assessment task was then completed. Students' scores were correlated against expert assessor scores. RESULTS: A total of 31 final year medical students participated. Student self-assessment scores before video feedback demonstrated moderate positive correlation with expert assessor scores (r = 0.48, p < 0.01) with no change after video feedback (r = 0.49, p < 0.01). After video feedback with benchmark performance demonstration, self-assessment scores demonstrated a very strong positive correlation with expert scores (r = 0.83, p < 0.0001). CONCLUSIONS: The demonstration of a video-recorded benchmark performance in combination with video feedback may significantly improve the accuracy of students' self-assessments.

Effects of ground EMS and ED personnel on air medical trauma on-site times.

INTRODUCTION: On-site times for helicopter EMS (HEMS) providers are hypothesized to increase when procedures indicated by national standards of care and local HEMS are not consistently completed by ground EMS (GEMS) or ED providers before HEMS arrival in trauma cases. METHODS: In this prospective study, we divided all trauma missions (120) flown by a university-based HEMS during a 3-month period into interfacility missions (between hospitals, ground providers are ED personnel) and scene missions (between scenes and hospitals, ground providers are GEMS). HEMS completed forms identifying which procedures were completed and omitted by GEMS or ED providers. We collected relevant times from county dispatchers and HEMS flight control. RESULTS: Ground providers frequently did not complete indicated basic and advanced procedures. A relationship existed between scene GEMS omissions and HEMS on-site times. If no procedures were omitted, average HEMS time on-site was 13 minutes, increasing to 17 minutes for one procedure omitted and 20 minutes for two or more. No relationship was found on interfacility missions between ED provider omissions and HEMS on-site times. However, any existing effect may have been eclipsed by external factors significantly extending HEMS on-site times (mean 43 minutes). An average of 93 minutes elapsed between the request for HEMS transport and patient arrival at the transferring hospital. CONCLUSION: GEMS frequently omit indicated procedures. For scene missions, reducing the number of indicated procedures omitted by scene GEMS providers could reduce on-site HEMS times. For interfacility missions, further study is indicated to determine what occurs before HEMS is contacted and while HEMS is on-site.

The respiratory complications of leptospirosis.

Leptospirosis is an uncommon disease. Respiratory failure attributable to this infection is unusual, but remains a major cause of mortality. Mechanical ventilation has been required for patients with significant alveolar hemorrhage and the adult respiratory distress syndrome. We report a patient with ventilatory failure due to the severe muscle weakness associated with leptospirosis and review the pulmonary consequences of this infection.

SSI: trends in state supplementation, 1979-81.

In December 1979, the number of persons receiving State supplementary payments under the Supplemental Security Income Program for the Aged, Blind, and Disabled totaled 1,942,000. By December 1981, the number totaled 1,875,000--a decline of 67,000 or 3 percent. This decrease paralleled the reduction in the number of persons receiving Federal Supplemental Security Income payments, which dropped from 3,687,000 to 3,590,000 or 3 percent during the 3-year period. Changes also occurred in the distribution of persons by eligibility category. The number of persons eligible because of age declined 9 percent, from 823,000 to 745,000; persons eligible because of blindness increased 1 percent, from 41,000 to 42,000; and persons eligible because of disability increased 1 percent, from 1,076,000 to 1,086,000. In contrast to the trend in the State supplementation caseload, expenditures for State supplementary payments continued to increase as they have since the beginning of the Supplemental Security Income program.

SSI: characteristics of persons receiving federally administered State supplementation only.

This article summarizes the demographic and economic characteristics of the half million persons on the rolls of the Supplemental Security Income (SSI) program in January 1981 whose only payment was a federally administered State supplement. All of these persons were ineligible for a Federal SSI payment because their countable income from other sources exceeded $258 (the Federal benefit rate plus the $20 Federal income disregard). The data indicate that 62 percent of these persons resided in California; nearly 75 percent were aged 65 or older; 81 percent were white; and 65 percent were women. Almost all of these persons received a monthly Social Security benefit, which averaged $286. The average monthly State supplementary payment for the members of this group was $84.

SSI: trends in State supplementation, 1974-78.

Legislation establishing the SSI program and subsequent amendments provide for State payments to supplement the basic Federal SSI payment. For former public assistance recipients, State payments are required, if necessary, to maintain prior income levels. For those newly eligible, additional State payments are optional. At the beginning of SSI, most States elected to provide supplementary payments to those newly eligible as well as to former public assistance recipients. Since then, numerous changes have taken place. This article summarizes and analyzes changes that occurred in State supplementation under SSI from 1974 through 1978. Although nationwide few variations took place in State supplementation during the period, individual States experienced significant changes--primarily in the number of recipients and expenditures. Some of these changes occurred because of implementation of Federal-State legislation resulting in program expansion and/or benefit alterations. A significant shift took place in the distribution of recipients by eligibility category: the disabled became the major category, replacing the aged. The caseload for the blind, however, remained relatively stable.

Effect of SSI on Medicaid caseloads and expenditures.

The 1972 Social Security Amendments replaced the Federal-State public assistance programs for the needy aged, blind, and disabled with the Federal supplemental security income (SSI) program. They also changed the automatic Medicaid eligibility provision under title XIX of the Social Security Act for the cash assistance population. This article provides information about recent changes in State Medicaid caseloads and payments following implementation of SSI and the possible effects of SSI on such changes. It does not appear that SSI was a significant factor in the Medicaid changes. The growth in Medicaid payments resulted primarily from expansion of medical services to include care in intermediate care facilities, inflation, and higher utilization of medical services.