Design of an emergency teleradiology system based on progressive transmission

In clinical surgery, there are frequent needs for communication between the house staff and the attending physician in an emergency situation. To overcome the limitation of voice communication through the telephone line, we have designed an 'emergency teleradiology system' which can be used for emergency surgical and medical decision making. This system can transmit the high quality images of CT, MRI, and other X-ray data using a PC attached to a modem through the conventional telephone line. It is based on the progressive transmission system which enables the successive update of a received image. The iterative residual coding/decoding algorithm efficiently compresses the image to maximally utilize the low bandwidth PSTN channels. This system also satisfies design requirements such as low-cost, ease of operation, fast transmission, and interactive image communication including voice. Test results using several CT, MR, and X-ray images evaluate the compression performance, image quality, transmission time and computational time of the coding and decoding processes, thus demonstrate the usefulness of this system in an emergency situation.     

Pediatric elbow trauma

Acute pediatric elbow trauma is commonly seen in the emergency department (ED). Reports confirm that, compared to other fractures, children's elbow fractures are commonly misdiagnosed in the ED. In addition, missed orthopedic injuries are one of the leading causes of malpractice claims in emergency medicine. Radiologic diagnosis of these injuries is challenging, as a large portion of the pediatric elbow is composed of radiolucent cartilage. Knowledge of the normal anatomy and ossification centers around the elbow is essential for correct diagnosis. Acute neurovascular injury is frequently associated with these injuries, but is often difficult to assess in an apprehensive child. Immediate orthopedic consultation is indicated for any child with an elbow injury in whom neurologic or vascular compromise is suspected. Consultation should be strongly considered for children with displaced supracondylar fractures and/or significant echymosis and swelling about the cubital fossa.     

Use of a single stent for double ureter support in transplantation

Economical applications of teleradiology and telemedicine are limited to the existing telephone network infrastructure, which greatly limits the speed of digital information transfer. Telephone lines are inherently slow, requiring image transmission times to be unacceptably long for large, complex, or numerous images. JPEG (Joint Photographic Experts Group) image transmission has been shown to compress images to 10% of the original file size without a noticeable change in the quality of the image. This study was carried out to assess the quality of medical diagnostic images after JPEG compression and decompression. X-rays, computed tomography scans, and ultrasound samples were compressed and decompressed using JPEG. The compressed JPEG images were indistinguishable from the original images. The JPEG images were approximately 10% of the original file size. This would reduce image transmission times by 90% (eg, an unacceptable time of 50 minutes would be reduced to an acceptable time of 5 minutes). JPEG can be used to optimize teleradiology and telemedicine.     

Use of store and forward technology for vascular nursing teleconsultation service

Accurate assessment is critical in planning appropriate therapeutic management of a patient with a vascular wound. However, several factors may inhibit wound assessment by trained professionals or subspecialists. Multiple co-morbidities and lack of transportation and finances contribute to problems with access to specialty clinics for both rural and urban patients with vascular disease. To assess the application of telemedicine in meeting the needs of rural patients with vascular disease, the vascular nurse clinician of a regional medical network was incorporated into a telemedicine research project that used a still-image transmission system known as the Picasso telephone, which allows a diagnostic quality image to be transmitted over a regular telephone line. Telephone consultation between sender and receiver occurs simultaneously at the time of image transmission. Because images can be collected and stored for future reference, this technology is commonly called "store and forward" technology. The application of advanced technology in a rural health care environment has the potential to reduce costs for both patient and managed care insurance plans, allow for expert consultation from distant centers, and promote collegiality and learning among professionals.     

Is image selection a useful strategy to decrease the transmission time in teleradiology? A study using 100 emergency cranial CTs

This study examines the suitability of working with a selection of images in a teleradiology consulting system in neurological or neurosurgical emergency situations. The teleradiology system was based on IBM-compatible personal computers, video digitization for data acquisition, and data transmission by Integrated System Digital Network. Forty normal and 60 abnormal emergency cranial computed tomograms were shown to a radiologist on call who presented all cases he regarded as pathologic to a neuroradiologic expert by teleradiology. To reduce transmission time, only a selection of images from the CT study was presented (up to four images per case). For each case the on-call radiologist's diagnosis (D(on-call)), the expert's diagnosis on the teleradiology screen (D(monitor)), and the expert's diagnosis on the original film (D(original)) was documented, together with an estimation of the agreement between those diagnoses. There was clinically relevant disagreement between the on-call radiologist's diagnosis and the neuroradiologist's diagnosis based on the image selection on the teleradiology monitor in 23% of cases. A clinically important discrepancy between the neuroradiologist's diagnosis based on the image selection and his diagnosis using the original films was found in 30% of cases. This was due to the presence of clinically relevant information on images not transferred by the on-call radiologist. Image quality of the transferred images was sufficient in all cases. Drastic selection of images from a complete CT study leads to a high rate of incorrect diagnoses and is not appropriate to reduce transmission time in teleradiology.     

Teleradiology in rural imaging centres

An economic analysis of a private commercial magnetic resonance (MR) imaging service was carried out. At an expected case-load of 2000 per year, a mid-field MR unit was predicted to cost $470 per case using teleradiology and $544 per case using film and a courier service. Routine and emergency MR services were provided to two communities in Maryland. In a two-year study period, 8083 teleradiology examinations were performed. Digital images were acquired and transmitted without data compression via ISDN at 128 kbit/s to a central diagnostic workstation for interpretation by a team of radiologists. The average transmission time for a typical case of 50 images was 6-8 min. Preliminary interpretations were normally available within 2 h and the final transcribed reports were usually faxed to the physicians' offices within 24 h. The results of a survey indicated that the system was well received by both referring physicians and patients. Costs per case in practice were similar to those predicted.     

A cryptologic based trust center for medical images

OBJECTIVE: To investigate practical solutions that can integrate cryptographic techniques and picture archiving and communication systems (PACS) to improve the security of medical images. DESIGN: The PACS at the University of California San Francisco Medical Center consolidate images and associated data from various scanners into a centralized data archive and transmit them to remote display stations for review and consultation purposes. The purpose of this study is to investigate the model of a digital trust center that integrates cryptographic algorithms and protocols seamlessly into such a digital radiology environment to improve the security of medical images. MEASUREMENTS: The timing performance of encryption, decryption, and transmission of the cryptographic protocols over 81 volumetric PACS datasets has been measured. Lossless data compression is also applied before the encryption. The transmission performance is measured against three types of networks of different bandwidths: narrow-band Integrated Services Digital Network, Ethernet, and OC-3c Asynchronous Transfer Mode. RESULTS: The proposed digital trust center provides a cryptosystem solution to protect the confidentiality and to determine the authenticity of digital images in hospitals. The results of this study indicate that diagnostic images such as x-rays and magnetic resonance images could be routinely encrypted in PACS. However, applying encryption in teleradiology and PACS is a tradeoff between communications performance and security measures. CONCLUSION: Many people are uncertain about how to integrate cryptographic algorithms coherently into existing operations of the clinical enterprise. This paper describes a centralized cryptosystem architecture to ensure image data authenticity in a digital radiology department. The system performance has been evaluated in a hospital-integrated PACS environment.     

A remote conference system for image diagnosis on the World-Wide Web

OBJECTIVE: The World-Wide Web on the Internet enables an exchange of multimedia information among remote desktop computers. Therefore, a teleradiology system using the Web would allow remote consultation with expert radiologists. Our objective was to establish a Web-based prototype system for image interpretation. CONCLUSION: Our system allows a physician to transmit clinically useful images to an expert radiologist at a different location, who can see them on a Web browser and discuss diagnoses with the physician.     

Quantitative changes in the ultrastructure of myocardial cells in Japanese quail during hypergravity, hypodynamia and space flight

To assess the consultation patterns of pediatric emergency physicians in the management of injured children and to describe the spectrum of pediatric trauma, we retrospectively reviewed 601 patients treated in the emergency department for injuries during four one-week periods at a designated level I regional pediatric trauma center (50,000 patients/year) with a pediatric emergency medicine fellowship. The majority (94%) of pediatric trauma was minor; only 2% of children had injuries severe enough to require direct transfer to the operating room. The highest volume of patients, the greatest number of consultations, and the majority of admissions to the operating room occurred between 4 PM and midnight. No patients went to the operating room on the night shift. Musculoskeletal injuries constituted the predominant category of pediatric trauma, and lacerations were the most common specific injury. One half of all procedures involved laceration repair, and one third involved splinting or casting. Four hundred ten patients (68%) were managed by physicians in the emergency department without consultation. The orthopedic service performed one half of all consultations and admitted the largest number of patients; the majority of patients taken directly to the operating room had musculoskeletal injuries.(ABSTRACT TRUNCATED AT 250 WORDS)     

Spatial resolution of body surface potential maps and magnetic field maps: a simulation study applied to the identification of ventricular pre-excitation sites

Telemedicine is defined as the "delivery of health care and sharing of medical knowledge over a distance using telecommunication systems." The concept of telemedicine is not new. Beyond the use of the telephone, there were numerous attempts to develop telemedicine programs in the 1960s mostly based on interactive television. The early experience was conceptionally encouraging but suffered inadequate technology. With a few notable exceptions such as the telemetry of medical data in the space program, there was very little advancement of telemedicine in the 1970s and 1980s. Interest in telemedicine has exploded in the 1990s with the development of medical devices suited to capturing images and other data in digital electronic form and the development and installation of high speed, high bandwidth telecommunication systems around the world. Clinical applications of telemedicine are now found in virtually every specialty. Teleradiology is the most common application followed by cardiology, dermatology, psychiatry, emergency medicine, home health care, pathology, and oncology. The technological basis and the practical issues are highly variable from one clinical application to another. Teleradiology, including telenuclear medicine, is one of the more well-defined telemedicine services. Techniques have been developed for the acquisition and digitization of images, image compression, image transmission, and image interpretation. The American College of Radiology has promulgated standards for teleradiology, including the requirement for the use of high resolution 2000 x 2000 pixel workstations for the interpretation of plain films. Other elements of the standard address image annotation, patient confidentiality, workstation functionality, cathode ray tube brightness, and image compression. Teleradiology systems are now widely deployed in clinical practice. Applications include providing service from larger to smaller institutions, coverage of outpatient clinics, imaging centers, and nursing homes. Teleradiology is also being used in international applications. Unresolved issues in telemedicine include licensure, the development of standards, reimbursement for services, patient confidentiality, and telecommunications infrastructure and cost. A number of states and medical boards have instituted policies and regulations to prevent physicians who are not licensed in the respective state to provide telemedicine services. This is a major impediment to the delivery of telemedicine between states. Telemedicine, including teleradiology, is here to stay and is changing the practice of medicine dramatically. National and international communications networks are being created that enable the sharing of information and knowledge at a distance. Technological barriers are being overcome leaving organizational, legal, financial, and special interest issues as the major impediments to the further development of telemedicine and realization of its benefits.     

Posttraumatic elbow arthritis and arthroplasty

Elbow contractures without significant articular injury can be treated with soft-tissue procedures, such as joint capsular releases, resection of heterotropic ossification, and joint debridement. Elbows with significant intra-articular injuries or posttraumatic arthritis require some form of joint reconstruction, such as a distraction arthroplasty, interposition arthroplasty, or implant replacement arthroplasty. With a better understanding of the surgical indications for elbow arthroplasty, improvements in surgical technique, improvements in elbow implants, and increased surgical experience, the results of implant arthroplasty for the posttraumatic elbow continue to improve.     

The use of autogenous fat, fascia, and nonvascularized muscle grafts in the head and neck

We have reviewed the transplantation of autogenous fat, fascia, and nonvascularized muscle. Although none of these tissues satisfies all of the requirements for an ideal transplantation material, understanding the indications and each material's limitations will broaden the surgeon's armamentarium when soft-tissue grafting is desired. Although the use of autogenous fat grafts in head and neck surgery has been associated with some unpredictability, fat remains an excellent choice for obliteration of frontal sinuses, for myringoplasty, and for limited soft-tissue augmentation. In most applications, significant resorption of the transplanted fat can be expected, and it should be compensated for accordingly by initial overcorrection. Future research endeavors, including development of preadipocyte transplants and hormonal manipulation of fat grafts, will perhaps improve results of transplantation. The grafting of fascia has been shown to be a very reliable technique, especially when tensile strength is required of the transplant material. In grafts, fascia is much more predictable than fat, in that the majority of the fascia survives as living tissue that retains its original characteristics. A relative lack of three-dimensional bulk, however, limits the use of fascia in soft-tissue augmentation. The transplantation of nonvascularized muscle, because of its enormous metabolic requirements, almost always results in death of the muscle cells and subsequent partial replacement by fibrous tissue. Free muscle grafts therefore have very limited application, except in circumstances in which fibrous tissue obliteration of small defects (such as the nasofrontal duct or eustachian tube) is the desired result. In clinical situations in which maintenance of the substance or bulk of the transplanted material is of paramount importance, consideration should be given instead to the transfer of vascularized tissue. For this purpose, numerous simple and composite flaps of fascia, fat, muscle, and other tissues are now available. Vascularized tissue transfers are certainly not the solution to every reconstructive problem, however. When properly selected and applied, the transplantation of fat, fascia, and occasionally muscle remains an important option for soft-tissue replacement in head and neck surgery.     

Acute administration of cocaine, but not amphetamine, increases the level of synaptotagmin IV mRNA in the dorsal striatum of rat

We reviewed the real and potential ocular problems in all head and neck injuries at a tertiary care and regional trauma center from April of 1994 to March of 1995. Through a retrospective study, 127 charts were reviewed, specifically looking at the mechanism of injury, types of injury, whether there was any ocular trauma noted in the chart, and whether there was a consultation to the ophthalmology department. Forty-one of these patients were seen by an ophthalmologist as the initial consultant for ocular and orbital injuries recognized by the emergency staff. In the 86 remaining patients, signs of potential ocular injury were recorded in the chart in 62 (72%) of these patients, yet an ophthalmology consultation was requested for only 23 of them (37%). This survey reveals the lack of awareness in a regional trauma center of certain ocular and periocular signs that may be indicative of more serious ocular injuries. It is the purpose of this article to highlight these concerns to the various health professionals involved with head and neck trauma patients in the hope that the patients will, in the end, benefit from a more thorough and complete assessment of the potential ocular and periocular injuries.     

Maternal-fetal transfers: indications, appropriateness, and cost

The objective of this study was to assess the indications, appropriateness, and cost of maternal-fetal transfers to a tertiary care facility in an era of managed care. Our perinatal database was reviewed from January 1, 1996 through June 30, 1997 to determine maternal and fetal indications for transfer, referring institution characteristics, utilization of tertiary level services, and cost of transfer. There were 273 transfers from 53 referring hospitals ranging in distance from <20 miles (n = 102) to >100 miles (n = 41). Thirty-one patients were transferred by air (average cost $7656), 238 by ground (average cost $920), 4 by private car. The referring diagnosis was preterm premature rupture of membranes (PPROM) (n = 80), preterm labor (n = 76), preeclampsia (n = 42), medical complications (n = 25), or other (n = 50). Mean gestational age (GA) at transfer was 28.5+/-5.5 weeks. Patients were referred from hospitals with a self-designated nursery level I (n = 115), II (n = 111), III (n = 45), or none (n = 2). In 42 patients, (15%) no maternal or fetal indication for hospital transfer was identified after evaluation at the tertiary center. The most common referring misdiagnoses were preterm labor (n = 25), PPROM (n = 10) and preeclampsia (n = 3). One hundred and sixty-five patients delivered during transfer admission (mean GA = 29.6+/-4.8 weeks); 79 infants (48%) required admission to a level III, and 52 (31%) to a level II nursery. Most patients require the services of a tertiary facility after maternal fetal transfer. If delivered during transfer admission, the majority of neonates require care in an intermediate or intensive care nursery.     

Cervical spine radiographs in the trauma patient

Significant cervical spine injury is very unlikely in a case of trauma if the patient has normal mental status (including no drug or alcohol use) and no neck pain, no tenderness on neck palpation, no neurologic signs or symptoms referable to the neck (such as numbness or weakness in the extremities), no other distracting injury and no history of loss of consciousness. Views required to radiographically exclude a cervical spine fracture include a posteroanterior view, a lateral view and an odontoid view. The lateral view must include all seven cervical vertebrae as well as the C7-T1 interspace, allowing visualization of the alignment of C7 and T1. The most common reason for a missed cervical spine injury is a cervical spine radiographic series that is technically inadequate. The "SCIWORA" syndrome (spinal cord injury without radiographic abnormality) is common in children. Once an injury to the spinal cord is diagnosed, methylprednisolone should be administered as soon as possible in an attempt to limit neurologic injury.     

Technology transfer in digital mammography. Report of the Joint National Cancer Institute-National Aeronautics and Space Administration workshop of May 19-20, 1993

Digital mammography is one of the most promising novel technologies for further improvement of early detection of breast cancer, offering important potential advantages: 1) improved image quality; 2) digital image processing for improved lesion contrast; 3) computer-aided diagnosis for enhanced radiologic interpretation; and 4) teleradiology for facilitated radiologic consultation. The Diagnostic Imaging Research Branch of the National Cancer Institute (NCI) recently funded an international, multidisciplinary, multi-institutional Digital Mammography Development Group for collaborations between NCI, the academic community, and industry to facilitate the integrated development and implementation of digital mammographic systems. Currently, however, digital mammography faces a number of fundamental technological roadblocks: 1) cost-effective digital detectors and displays for imaging systems; 2) the need for novel algorithms for image processing and computer-aided diagnosis; and 3) high performance, low cost digital networks to provide an "information superhighway" for teleradiology. To solve some of these technological problems, the Diagnostic Imaging Research Branch of NCI joined efforts with the Technology Transfer Division of the National Aeronautics and Space Administration to pursue a federal technology transfer program in digital mammography. The authors discuss the findings and recommendations of the workshop entitled "Technology Transfer in Digital Mammography," which was organized and held jointly by the NCI and the National Aeronautics and Space Administration in May, 1993. Numerous innovative technologies of varying degree of promise for digital mammography were presented at the conference. In this article, specific technologies presented at the workshop by the federal and federally-supported laboratories are described, and critiques of these technologies by the leaders of the medical imaging community are presented.     

Endothelial adhesion molecules for nasal-homing T cells in allergy

We identified a shear fracture of the distal articular surface of the humerus, with anterior and proximal displacement of the capitellum and a portion of the trochlea, in six patients (five female and one male). The average age of the patients was thirty-eight years (range, ten to sixty-three years). Each fracture was the result of a fall from a standing height. A characteristic radiographic abnormality, which we have termed the double-arc sign, was seen on the lateral radiograph of each patient and represented the subchondral bone of the displaced capitellum and the lateral trochlear ridge. All patients were managed with open reduction, internal fixation, and early motion of the elbow. The average duration of follow-up was twenty-two months (range, eighteen to twenty-six months). The fracture united in all patients at an average of six weeks (range, four to nine weeks), without radiographic evidence of osteonecrosis of the fracture fragment. Flexion of the elbow averaged 141 degrees (range, 130 to 150 degrees), with an average flexion contracture of 15 degrees (range, 0 to 40 degrees). Pronation of the forearm averaged 83 degrees, and supination averaged 84 degrees. All patients had a good or excellent functional result, according to the elbow-rating scale of Broberg and Morrey.     

Carcinoids of unknown origin: comparative analysis with foregut, midgut, and hindgut carcinoids

The purpose of this study was to analyze our results of surgical treatment of arthrogryposis of the elbow and to compare our tendon transfer results using range of motion (ROM) criteria versus functional use criteria. Eighteen tendon transfers for elbow flexion in 14 children with arthrogryposis with an average follow-up period of 4 years (range, 1-14 years) and 6 elbow capsulotomies with triceps lengthening in 6 children with arthrogryposis with an average follow-up period of 5 years (range, 2-9 years) were evaluated. Each child was assessed by a questionnaire regarding functional use of the upper extremity, physical examination of ROM and strength, and a videotaped activities of daily living evaluation. Tendon transfer results were classified and compared using 2 methods of evaluation: postoperative strength and ROM and effective functional use of the tendon transfer to perform activities of daily living. The 6 elbow capsulotomies improved from an average preoperative arc of 17 degrees of motion (average extension, -2 degrees; average flexion, 19 degrees) to an average final follow-up arc of 67 degrees (average extension, -25 degrees; average flexion, 92 degrees). The 18 tendon transfers evaluated by strength and ROM criteria showed 9 triceps to biceps transfers in 9 arms (7 good, 1 fair, and 1 poor), 5 pectoralis to biceps transfers in 4 arms (1 good, 3 fair, and 1 poor), and 4 latissimus dorsi to biceps transfers in 3 arms (2 good and 2 fair). Evaluation by functional use criteria gave the same result in 13 transfers and downgraded the result in 5; the downgraded results were due to resultant flexion contracture or limited functional use because the transfer was in the nondominant arm. Based on this review, optimal surgical candidates for tendon transfer are children older than 4 years, who have full passive ROM of the elbow in the dominant arm, and at least grade 4 strength of the muscle to be transferred.     

Preliminary experience with transluminal laser-induced intrahepatic portacaval shunts

This article outlines the objectives for a resident rotation on a pediatric emergency medicine service that is geographically separate from adult-oriented facilities. In this setting, pediatric emergency department care is considered an off service. However, these objectives incorporate key pediatric knowledge and techniques in a practical format for emergency medicine trainees who have no separate pediatric emergency department experience. The content of the pediatric emergency department educational exposure can be attained in a concentrated 2-month exposure at a pediatric facility or extracted throughout the course of multiple pediatric encounters at a general emergency department. These objectives are a part of a continuing series on the goals and objectives to direct emergency medicine resident training on off-service rotations.     

Anomalies of the branchial apparatus

Developmental abnormalities of the branchial apparatus represent a common cause of congenital lateral neck mass. Most often this is seen in the pediatric population but certainly may present at a much later age. The branchial apparatus contributes to major development of the head and neck, and a thorough understanding of embryology and anatomy is essential in treating these patients. Branchial anomalies may present as a cyst, sinus, or fistula; infection frequently complicates successful long-term management. Most often these lesions can be diagnosed by thorough history and physical examination. Complete surgical excision is the treatment of choice; however, recurrences may be encountered especially in those patients with a history of prior surgery or local infection.