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Facsimile transmission of radiographic images. Preliminary experiments with a personal computer and a fax modem board.
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Mail by modem: the BITNET connection.
Nursing faculty in university settings are now able to communicate with colleagues around the country or in other parts of the world through electronic networks such as BITNET. This article describes how members of the Southern Nursing Research Society's (SNRS) Governing Board used the BITNET system for accomplishing the society's work. Essential hardware and software requirements for using the network are described. Guidelines for logging on, sending messages, and e-mail courtesy are explained. Examples are included for using the network for 1) research and manuscript collaboration; 2) organizational communication and planning; and 3) teaching activities.
Secure transmission of urologic images and records over the Internet.
PURPOSE: Telemedicine has become a common method for the transmission of images and patient data across long distances. Our goal was to assess the efficiency and accuracy of Photomailer MD software, a store-and-forward telemedicine system, in the urologic setting. METHODS: Photomailer MD software was loaded on two computers in the host institution, one with a T1 connection to the Internet and the other with a dial-up modem connection (24,000 bits/second), and computers at three remote sites. A total of 14 clinical cases, comprised of digitized histories and radiographic images, were sent to the remote institutions four separate times using the four transmission modes available: nonencrypted, 56-bit encryption, 128-bit encryption, and 128-bit encryption with password. The following data points were recorded: file size before and after encryption, file transmission times, and diagnostic accuracy of the remote urologists. One-way ANOVA was used to compare mean values statistically, while the z-test was used to compare diagnostic accuracies. RESULTS: Encryption increased the file size by a mean of 37.8%, with the three encryption modes increasing file sizes by the same number of kilobytes. When a dial-up modem was used, encrypted files required a significantly longer transmission time (P < 0.05) than the unencrypted files. The same trend was seen with the T1 connection, although the differences often were not significant. When T1 transmission times were compared with modem times with other variables held constant, modem times were significantly longer (P < 0.05). Diagnostic accuracies for each of the three remote centers ranged from 85.7% to 100%. Differences in accuracy rates between attending physicians and residents were not significant. CONCLUSIONS: Photomailer MD provides a secure, convenient, and affordable method of transmitting patient images and records via the Internet. Transmission speed was significantly greater when using a T1 line and also tended to be faster when files were not encrypted. There was no significant difference in transmission time among the three encryption modes; therefore, 128-bit encryption with a password should be used to maximize security. Diagnostic accuracies were comparable to those in the literature. In general, 640 x 480-pixel resolution was adequate for urologic diagnoses, although higher-resolution images may improve accuracy.
Infrared transmission of electronic information via LAN in the operating room.
Recent advances in technology have brought many kinds of monitoring devices into the operating room (OR). The information gathered by monitors can be channeled to the operating ward information system via a local area network (LAN). Connecting patients to monitors and monitors to the LAN, however, requires a large number of cables. This wiring is generally inconvenient and particularly troublesome if the layout of the OR is rearranged. From this point of view, wireless transmission seems ideally suited to clinical settings. Currently, two modes of wireless connectivity are available: radio-frequency (RF) waves or infrared (IR) waves. Some reports suggest that RF transmission is likely to cause electromagnetic interference (EMI) in medical devices such as cardiac pacemakers or infusion pumps. The risk of malfunctioning life-sustaining devices and the catastrophic consequences this would have on seriously ill patients rules out the use of RF. Here, we report an IR system using IR modems for LAN connectivity in the OR. In this study, we focused on the possible detrimental effects of EMI during wireless connectivity. In our trial, we found no evidence of EMI of IR modems with any of the medical devices we tested. Furthermore, IR modems showed similar performance to a wired system even in an electrically noisy environment. We conclude that IR wireless connectivity can be safely and effectively used in ORs.
[The time scale in poxvirus evolution].
Unlike vertebrates and RNA-containing viruses, the objective estimate of molecular clock for DNA-containing viruses was so far absent. An extended central conservative genomic region of orthopoxviruses (about 102 kbp) and the sequence of DNA polymerase gene (about 3 kbp) of the viruses belonging to various genera from the family Poxviridae were analyzed. During this analysis, the known dating of variola virus (VARV) transfer from West Africa to South America (XVI century) and our own data on close phylogenetic relations between the modem West African and South American VARV isolates were used. As a result of this work, it was calculated for the first time that the rate of mutation accumulation in these DNA-containing viruses amounted to 0.9-1.2 x 10(-6) substitutions per site per year. The poxviruses started separating from the ancestor virus to form the modem genera approximately 500 thousand years ago; the ancestor of the genus Orthopoxvirus separated about 300 thousand years ago; and its division into the modem studied species took place approximately 14 thousand years ago.
Results of an Internet survey determining the most frequently used ankle scores by AOFAS members.
BACKGROUND: With technological advances in ankle arthroplasty, there has been parallel development in the outcome instruments used to assess the results of surgery. The literature recommends the use of valid, reliable, and responsive ankle scores, but the ankle scores commonly used in clinical practice remain undefined. METHODS: An internet survey of members of the American Orthopaedic Foot and Ankle Society (AOFAS) was conducted to determine which three ankle scores they perceived as most commonly used in the literature, which ones they believe are validated, which ones they prefer, and which they use in practice. RESULTS: According to respondents, the three most commonly used scores were the AOFAS Ankle score, the Foot Function Index (FFI), and the Musculoskeletal Outcomes Data Evaluation and Management System (MODEMS). The respondents believed that the AOFAS Ankle score, FFI, and MODEMS were validated. The FFI and MODEMS are validated, but the AOFAS ankle score is not validated. CONCLUSIONS: Most respondents preferred using the AOFAS Ankle score. The use of the empirical AOFAS Ankle score continues among AOFAS members.
Tapping the television cable.
Immediate access to patient data is essential to support good clinical decision making and support. However, away from the surgery, the doctor is currently unable to have any access to the clinical database. Solutions exist to support remote access, such as modems or radio data networks, but these are slow, with typical speeds in the 2-10 kbaud region. We propose a novel solution, to use the TV cable already installed in many homes. Using this technology, a suitably equipped computer (RF modern) is capable of connecting at speeds in excess of 500 kbaud and will run applications in exactly the same way as if connected to a surgery network: the cable TV becomes a LAN, but on a metropolitan scale. Brunel University, in collaboration with the Cable Corporation, has been piloting such a network. Issues include not only levels of service, but also security on the network and access, since the data are being effectively received in every home. However, close scrutiny of channel use can create closed networks reserved for specific users. The technology involves use of an RF modem to transmit data on a reverse channel (based at 16 MHz) on each subnet to a router at the head end of the cable network. This frequency translates the packet and retransmits it to all the subnets on a forward channel (based at 178 MHz). Each channel occupies the bandwidth normally allocated to one TV channel. Access is based on a modified CSMA/CD protocol, so treating the cable network as single multiple access network. The modem comes as a standard card installed in a PC and appears much as an ethernet card, but at reduced speed. With an NDIS driver it is quite able to support almost any network software, and has successfully demonstrated Novell and TCP/IP. We describe the HomeWorker network and the results from a pilot study being undertaken to determine the performance of the system and its impact on working practice.
Measuring improvement following total hip and knee arthroplasty using patient-based measures of outcome.
BACKGROUND: Patient-derived outcome scales have become increasingly important to physicians and clinical researchers for measuring improvement in function after surgery. The goal of the present study was to evaluate the ability of health-status instruments to measure early functional recovery after total hip and total knee arthroplasty. METHODS: Four hundred and six patients undergoing total hip arthroplasty and 266 patients undergoing total knee arthroplasty completed health-status questionnaires preoperatively and six months postoperatively to determine the standardized response mean. In the second phase of the study, a group of patients undergoing knee and hip arthroplasty were evaluated with several instruments before and after surgery to test for postoperative ceiling effects. RESULTS: The standardized response mean at six months was 1.7 for the MODEMS Hip Core, 1.2 for the MODEMS Knee Core, and 1.5 and 1.1 for the Physical Component Summary of the SF-36 for patients managed with hip and knee replacement, respectively. A standardized response mean of 1.0 is generally satisfactory for measuring improvement in orthopaedic surgery. In Phase 2 of the study, the vast majority of patients who had a score of 95 to 100 (that is, a maximum or near-maximum score) on the joint-specific scales generally believed that the hip or knee was normal and could not be better. CONCLUSIONS: The MODEMS, Oxford, and WOMAC scales all demonstrated a ceiling effect following total knee and total hip arthroplasty. These scores likely reflected the patients' perception of the status of the knee or hip rather than an inability to measure their improvement beyond the highest possible score. The Physical Component Summary score of the SF-36 had similar standardized response means when compared with hip and knee-specific instruments, and, therefore, consideration should be given to using this scale without a joint-specific scale for the measurement of improvement following total knee and total hip replacement, as a way to decrease responder burden (that is, the time required to complete the questionnaires).
Bandwidth constraints to using video and other rich media in behavior change websites.
BACKGROUND: Web-based behavior change interventions often include rich media (eg, video, audio, and large graphics). The rationale for using rich media includes the need to reach users who are not inclined or able to use text-based website content, encouragement of program engagement, and following the precedent set by news and sports websites. OBJECTIVES: We describe the development of a bandwidth usage index, which seeks to provide a practical method to gauge the extent to which websites can successfully be used within different Internet access scenarios (eg, dial-up and broadband). METHODS: We conducted three studies to measure bandwidth consumption. In Study 1, we measured the bandwidth usage index for three video-rich websites (for smoking cessation, for caregivers, and for improving eldercare by family members). We then estimated the number of concurrent users that could be accommodated by each website under various Internet access scenarios. In Study 2, we sought to validate our estimated threshold number of concurrent users by testing the video-rich smoking cessation website with different numbers of concurrent users. In Study 3, we calculated the bandwidth usage index and threshold number of concurrent users for three versions of the smoking cessation website: the video-rich version (tested in Study 1), an audio-rich version, and a Web-enabled CD-ROM version in which all media-rich content was placed on a CD-ROM on the client computer. RESULTS: In Study 1, we found that the bandwidth usage index of the video-rich websites ranged from 144 Kbps to 93 Kbps. These results indicated that dial-up modem users would not achieve a "good user experience" with any of the three rich media websites. Results for Study 2 confirmed that usability was compromised when the estimated threshold number of concurrent users was exceeded. Results for Study 3 indicated that changing a website from video- to audio-rich content reduced the bandwidth requirement by almost 50%, but it remained too large to allow satisfactory use in dial-up modem scenarios. The Web-enabled CD-ROM reduced bandwidth requirements such that even a dial-up modem user could have a good user experience with the rich media content. CONCLUSIONS: We conclude that the bandwidth usage index represents a practical tool that can help developers and researchers to measure the bandwidth requirements of their websites as well as to evaluate the feasibility of certain website designs in terms of specific use cases. These findings are discussed in terms of reaching different groups of users as well accommodating the intended number of concurrent users. We also discuss the promising option of using Web-enabled CD-ROMs to deliver rich media content to users with dial-up Internet access. We introduce a number of researchable themes for improving our ability to develop Web-based behavior change interventions that can better deliver what they promise.
[The Italian contribution to the application of high-technology methods to clinical trials].
Clinical trials are important research tools currently used in assessing new drugs and therapeutic strategies, which are unable to produce large effects evaluable in small series of patients. We describe methodological principles of clinical trials and significant advantages in their implementation produced by using a computer network for long-distance modem transmission of echocardiographic images and clinical data. This network has been recently developed in Italy and is operative at the University of Bari and the Associazione per la Ricerca in Cardiologia. Several clinical participating centers of the CEDIM Study and PHASE Study are connected in real time to a data center via modem by a special telephone network (RFD) of the Italian State Telephone Company (SIP). We describe the configuration, main features and applicative potential of such a powerful research tool in modem clinical trial methodology.
Web servlet-assisted, dial-in flow cytometry data analysis.
BACKGROUND: The obvious benefits of centralized data storage notwithstanding, the size of modern flow cytometry data files discourages their transmission over commonly used telephone modem connections. The proposed solution is to install at the central location a web servlet that can extract compact data arrays, of a form dependent on the requested display type, from the stored files and transmit them to a remote client computer program for display. METHODS: A client program and a web servlet, both written in the Java programming language, were designed to communicate over standard network connections. The client program creates familiar numerical and graphical display types and allows the creation of gates from combinations of user-defined regions. Data compression techniques further reduce transmission times for data arrays that are already much smaller than the data file itself. RESULTS: For typical data files, network transmission times were reduced more than 700-fold for extraction of one-dimensional (1-D) histograms, between 18 and 120-fold for 2-D histograms, and 6-fold for color-coded dot plots. Numerous display formats are possible without further access to the data file. CONCLUSIONS: This scheme enables telephone modem access to centrally stored data without restricting flexibility of display format or preventing comparisons with locally stored files.
A computer-based, automated, telephonic system to monitor patient progress in the home setting.
In this report we describe an automated, telephonic system to monitor the progress of patients convalescing at home. The system includes a computerized central station that is capable of automated voice communication over the telephone, using voice reproduction, and touch-tone recognition. Peripheral hardware in multiple monitored homes need include only a touch-tone telephone, but may also be augmented by inexpensive, rudimentary diagnostic aids, such as a scale for body weight, a thermometer, or a blood pressure cuff and manometer. Current central hardware includes a NeXT computer, a fax modem, and a specialized telecommunications modem developed specifically for voice telecommunication using the NeXT. The central station acts like a robotic nurse in that it asks patients a series of questions and records the responses. The subjective questions to be asked are patient individualized and pre-selected by the physician from a question menu including items targeted specifically for the patient's disease or condition. In addition, clinical data such as body weight, blood pressure, and body temperature obtained from in-home diagnostic aids may be transmitted to the central station over the telephone using touch tones. The time-of-day and frequency of calling are pre-selectable, according to the patient's preference and clinical status. Data obtained by the central station can be easily accessed by the duty nurse via menu driven software. Reports depicting significant responses as a function of time are generated in graphical format to facilitate rapid identification of adverse trends. Hard copy reports can be dispersed directly by fax. Results from a pilot study show patients with cardiac disease readily use the system without difficulty or complaints. In one patient a five pound increase in body weight was detected, which prompted the patient's cardiologist to adjust his medication. In this way automated telephone follow-up can provide early detection of complications before they become severe, making the home environment safer and more secure for convalescence and contributing to reduced health-care costs.
Opinion: a prototype for a computerized national mammography registry and tracking system using telecommunications and the Internet.
In this report, we analyze the feasability and discuss the potential benefits of using currently available technology for the wide-area registration and tracking of mammography patients. In our prototype, three dissimilar computer systems transmitted mammographic data (demographics and the results of mammograms) in a standardized format to a central data repository. Two of the three systems were dedicated computerized mammography systems and one was a general-purpose radiology information system. High-speed modems and the Internet were used to connect with the central repository, which could be queried in real time by remote users. Our results indicated that a busy mammography practice, using the slowest transmission method we tested (14-kilobaud modem), could transmit several days of mammographic data to a central repository in a matter of minutes. To implement systems that provide nation-wide mammographic tracking and follow up, more in-depth planning, development, and testing are necessary.
A semiautomated system for measurement of 96 simultaneous spectrophotometric enzyme assays.
A semiautomated system for spectrophotometric measurement of enzyme activity is described. In comparison to a 1-ml reaction volume monitored continuously by a conventional spectrophotometer, this system requires 1/10 to 1/100 the volume of sample, and 1/8 to 1/4 the time for measurement and computation of 96 enzyme assays. The system hardware consists of a 96-well platereader interfaced to a personal computer. Absorbances of 96 reactions are measured at timed intervals. These data are transmitted electronically from the platereader to the computer through the modem port using a modem program. The reaction rates are computed from the timed absorbance readings using a spreadsheet program. Three enzyme assays are presented, but the method has been used for several other assays and is applicable to many spectrophotometric rate assays. Many laboratories currently possess one or both of the two major components of the relatively inexpensive system described.
Csaba Horváth and preparative liquid chromatography.
Few chromatographers have been interested in furthering preparative liquid chromatography. The pioneers, Tswett, Kuhn and Lederer, A.J.P. Martin, Tiselius, isolated fractions but as an intermediate step in the analysis of their samples. The progress in electronics and sensors, and in their miniaturization has lead to the paradoxical situation that the analysts never see the transient pure fractions that their detector quantitates. Yet, over the last 25 years, preparative liquid chromatography has become an important industrial process for the separation, the extraction, and/or the purification of many pharmaceuticals or pharmaceutical intermediates, including pure enantiomers, purified peptides and proteins, compounds that are manufactured at the relatively large industrial scale of a few kilograms to several hundred tons per year. This development that has strongly affected the modem pharmaceutical industry is mainly due to the pioneering work of Csaba Horváth. His work in preparative HPLC was critical at both the practical and the theoretical levels. He was the first scientist in modem times to pay serious attention to the relationships between the curvature of the equilibrium isotherms, the competitive nature of nonlinear isotherms, and the chromatographic band profiles of complex mixtures. The thermodynamics of multi-component phase equilibria and mass transfer kinetics in chromatography attracted his interest and were the focus of ground-breaking contributions. He investigated displacement chromatography, an old method invented by Tiselius that Csaba was first to implement in HPLC. This choice was explained by the essential characteristic of displacement chromatography, in that it delivers fractions that can be far more concentrated than the feed. Remarkably, once the basics of nonlinear chromatography had been mastered in his group, most of the applications that were studied by his coworkers dealt with peptides of various sizes and with proteins. Thus, all the applications of preparative HPLC in the biotechnologies derive directly from Csaba's work. Although displacement did not pan out as a general method, the reasons are related more to practical constraints of the production of pharmaceuticals and to the long period of cheap energy that might be ending now. This report reviews Csaba's work in nonlinear chromatography.
New telemetric system for daily pulmonary function surveillance of lung transplant recipients.
BACKGROUND: Following lung transplantation, prompt diagnosis and therapy of acute pulmonary rejection and infection episodes relies primarily upon changes in pulmonary function and determines long-term outcome. We tested a new system that allows daily monitoring of the patient's pulmonary status even after discharge from the hospital. METHODS: Seven lung transplant recipients from our center were equipped with a telemetric monitoring device consisting of a portable flowmeter and a special modem unit. The flowmeter measures forced vital capacity (FVC), forced expiratory volume per second (FEV1), and mid expiratory flows (MEFs), encodes information like fever, cough, and dyspnea in a binary code form, and stores all values in a 32 kB memory unit. After its use, the patient positions the flowmeter onto the modem unit which automatically connects to a central computer at our center to transfer all saved data. The whole set can be used via any regular phone jack. The patient's file in the computer can be checked every day. RESULTS: All patients learned to use the unit during their postoperative stay or during later follow-up, and were able to apply the system at home. In a mean follow-up period of 10.3+/-2.2 months, 15 episodes of significant deterioration in home pulmonary function tests (PFTs) (>10%) were registered in 6 patients, which were all confirmed by in-hospital body plethysmography. They resulted in diagnoses of 4 episodes of acute rejection, 6 cases of beginning bacterial pneumonia, and 5 cases of, most likely, viral tracheobronchitis. Only 1 patient had to be admitted to the hospital. All patients PFTs returned to previous values after treatment. CONCLUSIONS: Telemetric monitoring of graft function in lung transplant recipients allows reliable early diagnosis and treatment of infection or rejection, which might help to prevent exacerbation of the pathology and reduce quantity of amounting graft dysfunction.
Percutaneous vertebroplasty for osteoporotic compression fractures: quantitative prospective evaluation of long-term outcomes.
PURPOSE: Osteoporotic vertebral compression fractures may cause debilitating pain that lasts for weeks or months, and which is often neither quickly nor completely relieved by conventional conservative therapy. Previous retrospective studies have suggested significant and nearly immediate pain relief, as well as rapid and sustained functional recovery, after percutaneous polymethylmethacrylate vertebroplasty (PPV). This prospective, quantitative study with long-term follow-up was designed to evaluate the safety and efficacy of PPV as a new treatment for patients with osteoporotic vertebral body compression fractures of the lumbar and thoracic spine. MATERIALS AND METHODS: PPV was performed in 30 patients with 54 symptomatic osteoporotic vertebral compression fractures who had a less-than-satisfactory response to conventional therapy. All procedures were performed by a single operator with significant experience in performing PPV. The Musculoskeletal Outcomes Data Evaluation and Management Scale (MODEMS) spinal intervention questionnaire, which includes the SF-36, was administered to all patients before intervention and exactly 2 weeks after the final PPV procedure. Pain and disability, treatment expectations and satisfaction, mental function, and quality of life were evaluated by four specialized modules, and responses to questionnaires preceding treatment were compared to those obtained at follow-up. Results of a long-term follow-up questionnaire were collected 15-18 months after the final vertebroplasty treatment. RESULTS: Our population consisted of three men and 27 women, with a mean age of 79 years. Fifty-four PPV procedures were performed for compression fractures in these 30 patients. Significant postprocedural improvement in all four MODEMS modules was demonstrated at 2 weeks (treatment score, P <.0001; pain and disability, P <.0001; physical function, P =.0004; and mental function, P =.0009). A small epidural leak of polymethylmethacrylate in one patient was asymptomatic and did not require intervention. At long-term follow-up (15-18 mo), 22 of 23 patients responding remained satisfied with the outcome of therapy and believed that the procedure had provided durable pain relief. Verbal pain scores documented significantly diminished back pain at 2 weeks (P <.0001) and again at long-term follow-up when compared to baseline (P <.0001). CONCLUSIONS: PPV is a safe and efficacious procedure for the relief of pain and disability after osteoporotic vertebral compression fractures. Patient satisfaction is high and persists when compared to preprocedural expectations; durable pain relief is provided.