The evolution of Shriners Hospitals for Children in North America

Shriners Hospitals for Children have been providing totally free care to children with neuromusculoskeletal disabilities since 1922. This mission expanded in 1962 to include the care of children with burn injuries and expanded in 1978 to include children with spinal cord injuries. Today, Shriners Hospitals for Children include 19 hospitals that provide pediatric orthopaedic care, four hospitals that provide acute and reconstructive burn care, and three hospitals in which spinal cord injury rehabilitation centers are located. During the past 20 years, case acuity and complexity have increased, comprehensiveness of care has been emphasized, members of the medical staff have increasingly become full-time, and sponsored intramural research has increased to a budget of $22 million annually. Annually, more than 250 orthopaedic residents receive pediatric orthopaedic training and more than 150 surgical residents are trained in pediatric burn care in Shriners Hospitals. In 1998, approximately 25,000 children were admitted for care, more than 22,000 operations were performed, and 236,000 children were treated as outpatients. In 1999, the annual operating budget for Shriners Hospitals for Children was $397 million.     

Physics and dosimetry in computed tomography

CT data acquisition and image reconstruction techniques are closely related to image quality and patient radiation dose. There is little question that technological developments currently underway will change the nature of both, and result in improved quality and diagnostic value of cardiovascular CT images while hopefully minimizing radiation dose to the patient.     

Reducing radiation dose for multi-phase contrast-enhanced dual energy renal CT: pilot study evaluating prior iterative reconstruction

Abdominal Radiology - Prior iterative reconstruction (PIR) uses spatial information from one phase of enhancement to reduce image noise in other phases. We sought to determine if PIR could reduce...     

Perspective on radiation risk in CT imaging

Awareness of and communication about issues related to radiation dose are beneficial for patients, clinicians, and radiology departments. Initiating and facilitating discussions of the net benefit of CT by enlisting comparisons to more familiar activities, or by conveying that the anticipated radiation dose to an exam is similar to or much less than annual background levels help resolve the concerns of many patients and providers. While radiation risk estimates at the low doses associated with CT contain considerable uncertainty, we choose to err on the side of safety by assuming a small risk exists, even though the risk at these dose levels may be zero. Thus, radiologists should individualize CT scans according to patient size and diagnostic task to ensure that maximum benefit and minimum risk is achieved. However, because the magnitude of net benefit is driven by the potential benefit of a positive exam, radiation dose should not be reduced if doing so may compromise making an accurate diagnosis. The benefits and risks of CT are also highly individualized, and require consideration of many factors by patients, clinicians, and radiologists. Radiologists can assist clinicians and patients with understanding many of these factors, including test performance, potential patient benefit, and estimates of potential risk.     

Measurement of half-value layer in x-ray CT: a comparison of two noninvasive techniques

The purpose of this paper is to determine the accuracy and reproducibility of two noninvasive methods of measuring half-value layer (HVL), ring and localization, compared with an invasive technique (suspending tube rotation). The ring method uses concentric aluminum rings about a CTDI ionization chamber at isocenter. Data were acquired using axial CT protocols (rotating x-ray tube, stationary patient table). The localization technique uses square aluminum sheets secured to the gantry shroud to filter the radiation beam, and a CTDI chamber suspended externally at isocenter. Data were acquired using localization image protocols (stationary x-ray tube, moving patient table). The invasive technique was similar to the localization technique except that the ion chamber was placed on the patient table and the tube rotation disabled using service software. Data for all techniques were collected on the same CT system. Independent data sets were collected to determine reproducibility. Sensitivity to ionization chamber lateral displacement from isocenter was investigated. Measured HVLs (mm aluminum, mean+/-std, n=4) were 7.19+/-0.03 (ring); 7.17+/-0.04 (localization); and 7.24+/-0.02 (service mode), which were not significantly different (p = 0.05). Displacing the chamber from isocenter changes the HVL, depending on the bow-tie filter, by as much as 5 mm aluminum. Aluminum filter to ion chamber distances of 25-35 cm provided accurate results. Both noninvasive techniques were accurate and reproducible at isocenter. However, the measured HVL was dependent upon the bow-tie filter and the lateral displacement of the ionization chamber with respect to isocenter. Greater than 2 cm off of isocenter, the ring technique did not provide accurate HVL measurements.     

Nasal tip projection. Quantitative changes following rhinoplasty

Fifty-one patients were enrolled in a study and underwent primary rhinoplasty. Serial nasal tip projection measurements were made preoperatively, intraoperatively, and 6 months postoperatively. Actual changes in measured nasal tip projection were evaluated with respect to preoperative goals and specific procedures used to accomplish these goals in the nasal tip. Several useful observations are made from these data: (1) The most important components of nasal tip projection in the postsurgical nasal tip are the medial crura, their attachment to the caudal septum, and the presence of additional cartilaginous grafts placed between the medial crura or beneath the crural feet. (2) Actual nasal tip projection will decrease postoperatively, unless measures to increase the length and strength of the medial crural segment are taken (ie, McCollough-modified Goldman tip procedure, cartilage struts, plumping grafts, etc), regardless of the preoperative goal. (3) The double-dome unit procedure is effective in narrowing the wide or bulbous lobule but alone does not permanently increase nasal tip projection. (4) Conservative tip procedures, such as a complete strip, result in decreased nasal tip projection and should therefore be used in patients in whom retrodisplacement of the nasal tip is the intended result.     

Volunteerism and Shriners Hospitals for Children

Shriners Hospitals for Children exemplifies the spirit of volunteerism and the remarkable effectiveness of this spirit in providing orthopaedic and burn care to thousands of children around the world. The voluntary efforts of Shriners have included fund raising, hospital planning and development, governance, identification of patients in need, and patient transportation. Until the 1980s, orthopaedic surgeons received little or no remuneration for their work in caring for children in Shriners hospitals. Subsequently, numerous factors have caused a conversion of a part-time voluntary medical staff to full-time and contracted part-time staff. Even so, many Shriners hospitals' medical staff members continue to volunteer their own time in caring for children in less fortunate countries, and as a corporation, Shriners Hospitals for Children has provided volunteer medical teams during times of major international disasters.     

Three-dimensional CT virtual endoscopy in the detection of simulated tumors in a novel phantom bladder and ureter model

BACKGROUND AND PURPOSE: Cystoscopy and ureteroscopy have limitations in the evaluation for urothelial tumors, and both are invasive. We studied the utility of three-dimensional (3D) CT virtual endoscopy in phantom models. MATERIALS AND METHODS: A phantom pelvis was constructed of Plexiglas, porcine pelvic bones, and processed animal fat and scanned at various table speeds in a four detector-row CT machine for ability to detect "tumors" of Solidwater plastic polymer. Images were reconstructed at slice thicknesses of 2.5 to 5.0 mm and reconstructed in 3D for evaluation by two radiologists with no knowledge of the scanning parameters or tumor location. Similar studies were performed with a ureter model. RESULTS: With 5-mm slices, the sensitivity for bladder tumors ranged from 67% for 2-mm tumors to 100% for 4-mm tumors, with 12 false-positive findings. The overall sensitivity was 86% with 3.75-mm slices with one false positive, and with 2.5-mm slices, the sensitivity was 93%, again with one false positive. For the ureteral tumors, the overall sensitivities and numbers of false positives were 88.9% and eight with 5.0-mm collimation, 88.9% and four with 3.75-mm collimation, and 100% and three with 2.5-mm collimation. The effective radiation dose for all studies was equivalent to that of a standard abdomen/pelvis scan. CONCLUSIONS: Although virtual endoscopy traditionally has had difficulty detecting tumors <5 mm, the multidetector-row CT protocols used in this study could detect most lesions smaller than this. The scan also depicts the other tissues of the pelvis, which is valuable for staging. The 3D images were produced using data from the CT urogram parameters standard at our institution.     

Skin wound approximation with new absorbable suture material

A new rapid strength loss catgut suture material can be used for skin closures in wounds of the face and body. Seventy-six comparisons were made under controlled conditions between the new material and one formerly recommended. The new material was used in 588 other wounds as well. It is concluded that the new material is superior to the other in several important ways.