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Jail-based competency restoration largely emerged as a method to address the backlog at forensic hospitals around the United States, as the number of justice-involved persons in need of restoration outgrew available beds. Jail-based competency restoration units (JBCRUs) appear to be highly effective and cost-saving. However, after the COVID-19 outbreak, services at some JBCRUs were stalled, as providers were forced to either quickly initiate or ramp up technology use to maintain services. The present study describes the course of programming for a JBCRU in Fulton County, Georgia, prior to and after the onset of COVID-19, during which time all treatment shifted to telehealth. A matched comparison group of prepandemic defendants was used to compare in-person versus telehealth services and findings indicated that while defendants' length of stay remained effectively the same, the restoration rate for telehealth increased remarkably over prepandemic levels (χ 2 = 10.1, p = .001). Such findings suggest that telehealth services are an effective mode of delivery for competency restoration., (© 2022 International Association for Correctional and Forensic Psychology.)

This study reports on restoration outcomes of a sample of pretrial defendants ( n = 877, 69% male) who were found incompetent to stand trial and underwent restoration services in a large urban county. Each male defendant was initially assigned to restoration in one of four settings on a continuum of services of varying intensity (ie, outpatient, jail general population, dedicated jail-based restoration unit, or forensic hospital inpatient unit) based on the defendant's assessed clinical need. Of those who received services on the jail-based restoration unit ( n = 398), 40 percent were restored to competency, 31 percent were diverted out of the criminal justice system, and 29 percent were referred for more intensive inpatient services, primarily because of refusal of medication (i.e., the jail would not allow involuntary medication, even if court-ordered). Advantages of restoration on the jail unit compared with inpatient hospitalization included more rapid institution of restoration services and higher rates of diversion out of the criminal justice system at one-third of the cost of inpatient restoration services. A continuum of restoration services that allows the type of restoration service to be matched to the needs of the individual incompetent defendant has significant advantages over routine transfer to a forensic hospital for restoration., (© 2020 American Academy of Psychiatry and the Law.)

Objective: Incomplete lupus erythematosus (ILE) involves clinical and/or serologic manifestations consistent with but insufficient for systemic lupus erythematosus (SLE) classification. Because the nature of ILE is poorly understood and no treatment recommendations exist, we examined the clinical manifestations, medication history, and immunologic features in a diverse collection of ILE and SLE patients., Methods: Medical records of subjects enrolled in the Lupus Family Registry and Repository were reviewed for medication history and American College of Rheumatology (ACR) classification criteria to identify ILE patients (3 ACR criteria; n = 440) and SLE patients (≥4 ACR criteria; n = 3,397). Participants completed the Connective Tissue Disease Screening Questionnaire. Anticardiolipin and plasma B lymphocyte stimulator (BLyS) were measured by enzyme-linked immunosorbent assay, antinuclear antibodies (ANAs) by indirect immunofluorescence, and 13 autoantibodies by bead-based assays., Results: On average, ILE patients were older than SLE patients (46.2 years versus 42.0 years; P < 0.0001), and fewer ILE patients were African American (23.9% versus 32.2%; P < 0.001). ILE patients exhibited fewer autoantibody specificities than SLE patients (1.3 versus 2.6; P < 0.0001) and were less likely to have ANA titers ≥1:1,080 (10.5% versus 19.5%; P < 0.0001). BLyS levels were intermediate in ILE patients (controls < ILE; P = 0.016; ILE < SLE; P = 0.008). Pericarditis, renal, or neurologic manifestations occurred in 12.5% of ILE patients and were associated with non-European American race/ethnicity (P = 0.012). Hydroxychloroquine use increased over time, but was less frequent in ILE than SLE patients (65.2% versus 83.1%; P < 0.0001)., Conclusion: Although usually characterized by milder symptoms, ILE manifestations may require immunomodulatory treatments. Longitudinal studies are necessary to understand how ILE affects organ damage and future SLE risk, and to delineate molecular pathways unique to ILE., (© 2017, American College of Rheumatology.)

Objective: SLE is traditionally classified using the American College of Rheumatology (ACR) criteria. The Systemic Lupus International Collaborating Clinics (SLICC) recently validated an alternative system. This study examined large cohorts of subjects with SLE and incomplete lupus erythematosus (ILE) to compare the impact of ACR and SLICC criteria., Methods: Medical records of subjects in the Lupus Family Registry and Repository were reviewed for documentation of 1997 ACR classification criteria, SLICC classification criteria and medication usage. Autoantibodies were assessed by indirect immunofluorescence (ANA, antidouble-stranded DNA), precipitin (Sm) and ELISA (anticardiolipin). Other relevant autoantibodies were detected by precipitin and with a bead-based multiplex assay., Results: Of 3575 subjects classified with SLE under at least one system, 3312 (92.6%) were classified as SLE by both systems (SLE both ), 85 only by ACR criteria (SLE ACR-only ) and 178 only by SLICC criteria (SLE SLICC-only ). Of 440 subjects meeting 3 ACR criteria, 33.9% (149/440) were SLE SLICC-only , while 66.1% (n=291, designated ILE) did not meet the SLICC classification criteria. Under the SLICC system, the complement criterion and the individual autoantibody criteria enabled SLE classification of SLE SLICC-only subjects, while SLE ACR-only subjects failed to meet SLICC classification due to the combined acute/subacute cutaneous criterion. The SLICC criteria classified more African-American subjects by the leucopenia/lymphopenia criterion than did ACR criteria. Compared with SLE ACR-only subjects, SLE SLICC-only subjects exhibited similar numbers of affected organ systems, rates of major organ system involvement (∼30%: pulmonary, cardiovascular, renal, neurological) and medication history., Conclusions: The SLICC criteria classify more subjects with SLE than ACR criteria; however, individuals with incomplete lupus still exist under SLICC criteria. Subjects who gain SLE classification through SLICC criteria exhibit heterogeneous disease, including potential major organ involvement. These results provide supportive evidence that SLICC criteria may be more inclusive of SLE subjects for clinical studies., Competing Interests: Competing interests: None declared.

Immune dysregulation in systemic lupus erythematosus (SLE) contributes to increased disease activity. African-American (AA) SLE patients have an increased prevalence of complications from disease flares and end-organ damage that leads to increased morbidity and early mortality. We previously reported alterations in inflammatory and regulatory immune mediator levels prior to disease flare in European American (EA) SLE patients. In the current study, we assessed baseline and follow-up plasma levels of 52 soluble mediators, including innate, adaptive, chemokine, and TNF superfamily members, in AA SLE patients who developed SELENA-SLEDAI defined flare 6 or 12 weeks after baseline assessment. These patients were compared to themselves during a comparable, clinically stable period (SNF, n = 18), or to demographically matched SLE patients without impending disease flare (NF, n = 13 per group). We observed significant (q < 0.05) alterations in 34 soluble mediators at baseline, with increased levels of both innate (IL-1α and type I interferons [IFN]) and adaptive cytokines (Th1-, Th2-, and Th17-type), as well as IFN-associated chemokines and soluble TNF superfamily members weeks before clinical disease flare. In contrast, stable SLE patients exhibited increased levels of the regulatory mediators IL-10 (q ≤ 0.0045) and TGF-β (q ≤ 0.0004). Because heterogeneous immune pathways were altered prior to clinical disease flare, we developed a soluble mediator score that encapsulates all mediators tested. This score is the sum of all log transformed, standardized soluble mediator levels assessed at baseline (pre-flare), weighted by their Spearman correlation coefficients for association with the SELENA-SLEDAI score at time of concurrent flare. While baseline SELENA-SLEDAI scores were similar between flare vs. NF (p = 0.7214) and SNF (p = 0.5387), the SMS was significantly higher in pre-flare SLE patients (Flare vs NF or SNF, p < 0.0001). By capturing alterations in the balance between inflammatory and regulatory mediators associated with SLE pathogenesis, the soluble mediator score approximates the immune status of SLE patients and provides a robust, predictive gauge of impending disease flare., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Objective: Rheumatic diseases cause significant morbidity within American Indian populations. Clinical disease presentations, as well as historically associated autoantibodies, are not always useful in making a rapid diagnosis or assessing prognosis. The purpose of our study was to identify autoantibody associations among Oklahoma tribal populations with rheumatic disease., Methods: Oklahoma tribal members (110 patients with rheumatic disease and 110 controls) were enrolled at tribal-based clinics. Patients with rheumatic disease (suspected or confirmed diagnosis) were assessed by a rheumatologist for clinical features, disease criteria, and activity measures. Blood samples were collected and tested for common rheumatic disease autoantibodies [antinuclear antibody (ANA), anti-cyclic citrullinated peptide antibodies (anti-CCP), rheumatoid factor (RF), anti-Ro, anti-La, anti-Sm, anti-nRNP, anti-ribosomal P, anti-dsDNA, and anticardiolipins]., Results: In patients with suspected systemic rheumatic diseases, 72% satisfied American College of Rheumatology classification criteria: 40 (36%) had rheumatoid arthritis (RA), 16 (15%) systemic lupus erythematosus, 8 (7%) scleroderma, 8 (7%) osteoarthritis, 4 (4%) fibromyalgia, 2 (2%) seronegative spondyloarthropathy, 1 Sjögren's syndrome, and 1 sarcoidosis. Compared to controls, RA patient sera were more likely to contain anti-CCP (55% vs 2%; p < 0.001) or RF IgM antibodies (57% vs 10%; p < 0.001); however, the difference was greater for anti-CCP. Anti-CCP positivity conferred higher disease activity scores (DAS28 5.6 vs 4.45; p = 0.021) while RF positivity did not (DAS28 5.36 vs 4.64; p = 0.15). Anticardiolipin antibodies (25% of rheumatic disease patients vs 10% of controls; p = 0.0022) and ANA (63% vs 21%; p < 0.0001) were more common in rheumatic disease patients., Conclusion: Anti-CCP may serve as a more specific RA biomarker in American Indian patients, while the clinical significance of increased frequency of anticardiolipin antibodies needs further evaluation.

Objective: To examine the relationship between circulating B lymphocyte stimulator (BLyS) levels and humoral responses to influenza vaccination in systemic lupus erythematosus (SLE) patients, as well as the effect of vaccination on BLyS levels, and to investigate clinical and serologic features of SLE that are associated with elevated BLyS levels., Methods: Clinical history, disease activity measurements, and blood specimens were collected from 60 SLE patients at baseline and after influenza vaccination. Sera were tested for BLyS levels, lupus-associated autoantibodies, serum interferon-α (IFNα) activity, 25-hydroxyvitamin D (25[OH]D), and humoral responses to influenza vaccination., Results: Thirty percent of the SLE patients had elevated BLyS levels, with African American patients having higher BLyS levels than white patients (P = 0.006). Baseline BLyS levels in patients were not correlated with humoral responses to influenza vaccination (P = 0.863), and BLyS levels increased postvaccination only in the subset of patients with BLyS levels in the lowest quartile (P = 0.0003). Elevated BLyS levels were associated with increased disease activity, as measured by the SLE Disease Activity Index, physician's global assessment, and Systemic Lupus Activity Measure in white patients (P = 0.035, P = 0.016, and P = 0.018, respectively), but not in African Americans. Elevated BLyS levels were also associated with anti-nuclear RNP (P = 0.0003) and decreased 25(OH)D (P = 0.018). Serum IFNα activity was a significant predictor of elevated BLyS in a multivariate analysis (P = 0.002)., Conclusion: Our findings indicate that African American patients with SLE have higher BLyS levels regardless of disease activity. Humoral response to influenza vaccination is not correlated with baseline BLyS levels in SLE patients, and only those patients with low baseline BLyS levels demonstrate an increased BLyS response after vaccination., (Copyright © 2011 by the American College of Rheumatology.)

Objectives: Vitamin D deficiency is widespread and has been associated with many chronic diseases, including autoimmune disorders. A study was undertaken to explore the impact of low vitamin D levels on autoantibody production in healthy individuals, as well as B cell hyperactivity and interferon α (IFNα) activity in patients with systemic lupus erythematosus (SLE)., Methods: Serum samples from 32 European American female patients with SLE and 32 matched controls were tested for 25-hydroxyvitamin D (25(OH)D) levels, lupus-associated autoantibodies and serum IFNα activity. Isolated peripheral blood mononuclear cells were tested for intracellular phospho-ERK 1/2 as a measure of B cell activation status., Results: Vitamin D deficiency (25(OH)D <20 ng/ml) was significantly more frequent among patients with SLE (n=32, 69%) and antinuclear antibody (ANA)-positive controls (n=14, 71%) compared with ANA-negative controls (n=18, 22%) (OR 7.7, 95% CI 2.0 to 29.4, p=0.003 and OR 8.8, 95% CI 1.8 to 43.6, p=0.011, respectively). Patients with high B cell activation had lower mean (SD) 25(OH)D levels than patients with low B cell activation (17.2 (5.1) vs 24.2 (3.9) ng/ml; p=0.009). Patients with vitamin D deficiency also had higher mean (SD) serum IFNα activity than patients without vitamin D deficiency (3.5 (6.6) vs 0.3 (0.3); p=0.02)., Conclusions: The observation that ANA-positive healthy controls are significantly more likely to be deficient in vitamin D than ANA-negative healthy controls, together with the finding that vitamin D deficiency is associated with certain immune abnormalities in SLE, suggests that vitamin D plays an important role in autoantibody production and SLE pathogenesis.

The objective of this study was to compute reference SEMG values for normal subjects of 13 parameters extracted in the time, frequency and bispectrum domain, from the Biceps Brachii (BB) muscle generated under isometric voluntary contraction (IVC). SEMG signals were recorded from 94 subjects for 5s at 10, 30, 50, 70 and 100% of maximum voluntary contraction (MVC). The Wilcoxon signed rank test was applied to detect significant differences or not at p<0.05 between force levels for each of the 13 parameters. The main findings of this study can be summarized as follows: (i) The time domain parameters turns per second and number of zero crossings per second increase significantly with force level. (ii) The power spectrum median frequency parameter decreases significantly with force level, whereas maximum power and total power increase significantly with force level. (iii) The bispectrum parameter, maximum amplitude, increases significantly with force level with the exception the transition from 30% to 50% MVC. Although, the tests for Gaussianity and linearity show no significant difference with force level, the SEMG signal exhibits a more Gaussian distribution with increase of force up to 70% MVC. The SEMG linearity test, which is a measure of how constant the bicoherence index is in the bi-frequency domain, shows that the signal's bicoherence index is less constant (hence, the signal is less linear) at 70% of MVC compared to 10, 30, 50 and 100% MVC. (iv) The time domain parameters have good correlation between them as well as, between each one of them and maximum and total power. The median frequency has a good (negative) correlation with the bispectrum peak amplitude. (v) No significant differences exist between values based on gender or age. The findings of this study can further be used for the assessment of subjects suffering with neuromuscular disorders, or in the rehabilitation laboratory for monitoring the elderly or the disabled, or in the occupational medicine laboratory.

Medical physics education and training requires the use of extensive imaging material and specific explanations. These requirements provide an excellent background for application of e-Learning. The EU projects Consortia EMERALD and EMIT developed five volumes of such materials, now used in 65 countries. EMERALD developed e-Learning materials in three areas of medical physics (X-ray diagnostic radiology, nuclear medicine and radiotherapy). EMIT developed e-Learning materials in two further areas: ultrasound and magnetic resonance imaging. This paper describes the development of these e-Learning materials (consisting of e-books and educational image databases). The e-books include tasks helping studying of various equipment and methods. The text of these PDF e-books is hyperlinked with respective images. The e-books are used through the readers' own Internet browser. Each Image Database (IDB) includes a browser, which displays hundreds of images of equipment, block diagrams and graphs, image quality examples, artefacts, etc. Both the e-books and IDB are engraved on five separate CD-ROMs. Demo of these materials can be taken from www.emerald2.net.

A review is presented of the existing finite element models developed from 1987 to 1996 for the biomechanics of lower-limb prostheses. Finite element analysis can be a useful tool in investigating the mechanical interaction between the residual limb and its prosthetic socket, and in computer-aided design and computer-aided manufacturing of prosthetic sockets. Various assumptions and simplifications are made in these models to simplify the actual problem with complex geometry, material properties, boundary and interfacial conditions, as well as loading situations. The analyses can provide the information on the stress distribution at the stump/socket interface and within the residual limb tissues. More recently, nonlinear models have been developed taking into consideration the process of socket rectifications, the slip/friction conditions and material large deformation. The models so far developed have provided some basic understanding of the biomechanics. Comparison of the predictions of these models with experimental measurements indicated that the predicted stresses were within the ranges measured, although one-to-one correspondence was difficult to achieve. Further research is still required in order to improve these models to obtain higher precision in the results taking into account nonlinear and dynamic effects.

A system for measuring pressures and bi-axial shear stresses at the body support interfaces has been developed. This system has been used, in five unilateral trans-tibial amputees, to investigate the stresses at multiple points on the residual limb and prosthetic socket interface during standing and walking. The subjects investigated regularly used a patellar-tendon-bearing socket. The maximum peak pressure at the measured points was 320 kPa over the popliteal area during walking. The maximum shear stress was 61 kPa over the medial tibia area. Variable wave-forms of stress during walking were observed at the different measured points. The influence of the angular alignment on the stresses was investigated on one subject. It was found that a miss-alignment of +/- 8 degrees produced a change in peak longitudinal shear stress of between 8% and 11.5%.

The frictional action at stump/socket interface is discussed by a simplified model and finite element model analyses and clinical pressure measurements. The friction applied to the stump skin produces stresses within tissue and these stresses may damage the tissues and affect their normal functions. The combination of normal and shear stresses is considered to be a critical factor leading to amputee's discomfort and tissue damage. However, friction at the stump/socket interface has a beneficial action. A simplified residual limb model and a finite element model using real geometry have been developed to analyse the support action of friction. Both results show that the friction plays a critical role both in supporting the load of the amputee's body during the support phase of the gait cycle and in preventing the prosthesis from slipping off the limb during swing phase. Pressure at the below-knee socket during walking were measured with conditions of different friction. The results reveal that a larger pressures was produced at the lubricated interface than at the normal interface. A proper choice of coefficient of friction will balance the requirements of relief of load stress and reduction of slip with the general ability to support loads.

This paper describes the performance testing of a novel transputer-based physiological digital signal processing (DSP) unit and its application in the interpretation of pulsed Doppler ultrasound signals, obtained from models of arterial stenoses. The first test used the DSP unit as a stand-alone spectrum analyser using (1) sinusoidal frequencies (50 Hz to 10 kHz) and (2) filtered white noise (centre frequency 3 kHz, bandwidth 2.5 kHz). For the second test, the DSP unit was attached to a 30-channel multi-gate Doppler ultrasound scanner (transmitting a 4.8 MHz pulse with a repetition frequency of 4.8 kHz) and a vessel tracking unit. The Doppler ultrasound signals obtained from steady flow (100-600 ml/min) in a rigid acrylic tube (internal diameter 6 mm) were then analyzed by the DSP unit and a commercially available system. Lastly, an in vitro investigation into the flow disturbances around very small stenoses (2-25% cross-sectional area reduction), using steady flow (100-600 ml/min), was undertaken. The results indicated that the system was capable of detecting stenoses as small as 5% cross-sectional area reduction.

A non-linear finite element model has been established to predict the pressure and shear stress distribution at the limb-socket interface in below-knee amputees with consideration of the skin-liner interface friction and slip. In this model, the limb tissue and socket liner were respectively meshed into 954 and 450 three-dimensional eight-node isoparametric brick elements, based on measurements of an individual's amputated limb surface; the bone was meshed into three-dimensional six-node triangular prism elements, based on radiographic measurements of the individual's residual limb. The socket shell was assumed to be a rigid boundary. An important feature of this model is the use of 450 interface elements (ABAQUS INTER4) which mimic the interface friction condition. The results indicate that a maximum pressure of 226 kPa, shear stress of 53 kPa and less than 4 mm slip exist at the skin-liner interface when the full body weight of 800 N is applied to the limb. The results also show that the coefficient of friction is a very sensitive parameter in determining the interface pressures, shear stresses and slip. With the growth of coefficient of friction, the shear stresses will increase, while the pressure and slip will decrease.

This paper, the first of two, details the design and in-vitro testing of a transputer-based physiological signal processing system. The heart of the system is a transputer-based digital signal processing (DSP) board which can act as a stand-alone spectrum analyser, designed to operate in the audio-frequency band up to 25 kHz. The board comprises a T800 processor, two A100 transversal filters, 12 bit A-D circuitry capable of sampling up to 48 kHz, memory and address mapper. The initial application of the system is for the detection of early arterial disease. For this the DSP board is harnessed to the front end of a multigate pulsed Doppler ultrasound scanner operating at 4.8 MHz insonation frequency and incorporating a vessel wall tracking unit. The complete system performs a Fourier transform on the backscattered signals, providing spectral information on discrete areas of flow (0.6 mm3) across the vessel lumen in real time. This first paper describes the hardware, and the second describes the performance testing of the system on the bench and an assessment of its ability to detect low grade stenoses during steady flow.

The parameter deceleration vs. acceleration (dc/ac) as derived from the instantaneous peak velocity is obtained by dividing the descending and ascending slopes of plotted velocity curves. Blood velocities were recorded with a specially designed continuous-wave ultrasonic Doppler unit which provides: the instantaneous peak velocity, the instantaneous mean velocity, the acceleration, and an indication of volume flow. A physical meaning to the dc/ac parameter is given through an analysis, based on an electrical model, of a small portion of an artery. This gives a simple relationship which only takes account of the assumed vascular resistances. Measurements were performed in 67 male subjects; 39 were normotensive control subjects and 28 had established moderate hypertension. In both groups there was an increase of dc/ac in passing from the supine to the erect position, the increase being more accentuated by hypertension. The variation of dc/ac with age was significantly different in both groups. The results suggest that this parameter is a sensitive indicator of variations in vascular reactivity and as an indicator of structural changes in the arterial wall.

The paper describes an in vitro study using a multi-gate Doppler ultrasound system to investigate flow disturbances in a blood analogue caused by small stenoses (2-25% cross-sectional area reduction), using steady flow (100-600 ml min-1) in a 6 mm diameter rigid artery model. The results indicate that stenoses greater than 5% were detectable.

There are a number of methods of evaluating digital blood flow in the vascular laboratory but none fulfills the criteria of providing a quick and reproducible diagnostic test for Raynaud's phenomenon. We present our experience with the use of high frequency ultrasound to provide direct real time imaging of the digital arteries. Using this method and a standardised cold challenge test, consisting of exposure of the hand to a temperature of 10 degrees C for 5 minutes, it is possible to distinguish patients with Raynaud's phenomenon from normal controls on the basis of extent of digital artery closure. The mean fall in digital artery diameter on cold challenge, expressed as a percentage of the original diameter, was 92.4% (S.D. = 16.4, S.E.M. = 2.1) in patients with Raynaud's phenomenon as against 8.7% (S.D. = 11.5, S.E.M. = 2.5) in a group of normal volunteers. Using a 45% fall in digital artery diameter as the diagnostic cut-off point, the test has a specificity of 100% and a sensitivity of 96.6% in differentiating patients with Raynaud's phenomenon from controls. It is suggested that the test could be used as objective confirmation of a clinical diagnosis and to assess the efficacy of therapeutic interventions.

The effects of shear forces externally applied to the skin surface on the underlying tissues have been investigated. An analysis of the internal stresses and strains was conducted using a simplified model incorporating elasticity theory. Skin blood flow was measured using laser Doppler flowmetry while variable shear forces over a range of 0-250 g were applied to the skin surface. The theoretical model predicts that the application of surface shear forces alters the internal stress distribution and makes the shear and compressive components of stresses increase ahead of the surface force application point. The force resulting from concomitant application of shear and normal force determines the internal maximum stress and strain. Theoretically, the shear force should have the same effects on the underlying tissues as normal force. The experimental investigations revealed that the skin blood flow decreased roughly linearly with the increase of shear forces. When a shear force equal to the normal force was applied, the flux decreased by 45%, nearly equal to the increasing magnitude (41%) of resultant of normal and shear forces.

Although normal pressures at the stump socket interface of the lower-limb amputee have been investigated, little is known about the shear stresses that also occur. Studies suggest that the combination of both shear and normal stresses significantly exacerbates discomfort and vascular and tissue damage. A means of simultaneously measuring normal and shear stresses will aid in the investigation and improvement of prosthetic fit. A miniature triaxial force transducer (4.9 x 16 mm diameter) has been developed which can be recessed into the socket wall. The principle of operation, construction, performance and limitations of the device are described. Preliminary measurements of the interface stress variations over the gait cycle in a supra-condylar PTB socket are presented. These show clear differences in the stress patterns present when two different prosthetic feet are used.

Colour Doppler ultrasound offers the possibility of imaging small vessels not visible by B-mode alone. The colour Doppler image of velocities allows the course of small vessels to be imaged in the X-Y plane of the scan provided the Doppler frequency shift is of sufficient magnitude. This permits alignments of the Doppler cursor, allowing angle correction to provide true velocity measurements from the Doppler shift obtained. Before attempting to make velocity measurements, however, it is essential to be aware of the possible error in the Z plane caused by the thickness of the Doppler sample volume. To quantify this source of error, hydrophone and flow-rig measurements were performed on an Acuson 128 colour Doppler scanner with both 5 MHz linear-array and 3.5 MHz phased-array transducers. Measurements of the transmitted pulses using a point hydrophone showed that both probes employ approximately 3.5 MHz Doppler pulses (in both colour and pulsed Doppler modes). The two transducers have the same axial resolution. In colour Doppler mode the axial length of the sample volume increases automatically with depth by up to 0.5 mm. Measurements of colour and pulsed Doppler signal strength were obtained in a controlled flow rig. Both transducers produced accurate colour flow images of the phantom at their optimum depths; flow velocity errors due to Z-plane thickness are less than 5%. There was, however, substantial error outside these optimum conditions (up to 20%).

This study evaluated the use of a high frequency A-mode ultrasound scanner (CUTECH DM70) for monitoring the digital artery vasospasm of Raynaud's Phenomenon (RP). The technique was evaluated on 12 RP patients and 12 age and sex matched controls. The diameter of a single digital artery was measured in these subjects over a range of finger temperatures between 14-35 degrees C. The reproducibility of the measurements was assessed by repeating the procedure in two subjects (a control and an RP patient) on 5 separate days. The results confirmed that the technique is reproducible and monitored vasospasm occurring in all 12 RP patients. In the temperature range tested, none of the controls developed digital artery vasospasm. At finger temperatures greater than 25 degrees C the response to thermal stimuli of the digital arteries in RP patients and controls was similar. However, at temperatures less than 25 degrees C a marked vasoconstriction leading to complete digital artery closure was seen in the RP patients and not in the controls. This technique may prove useful in monitoring RP patients.

This study assessed the use of high frequency ultrasound (CUTECH DM70) in the measurement of digital artery diameters. The accuracy of the technique was assessed using a model. Four silicone tubes of different diameters were embedded in opaque agar. Three independent observers measured the diameter of the tubes using the CUTECH DM70 and the measurements obtained were compared with those obtained using a travelling light microscope. The technique was then evaluated on digital arteries. Ten recordings of digital artery diameter were made at a fixed point on the index finger in two subjects at 20 degrees C and at 30 degrees C. There was no statistical difference between the mean diameters obtained by the three observers using the CUTECH DM70 on the model. No statistical difference was noted when the mean diameters measured using the travelling microscope were compared with those obtained by the three observers. The diameter differences between the tubes were all highly significant (P less than 0.001 Mann Witney). The variability in the recordings of digital artery diameter in the two subjects was very low (maximum coefficient of variance less than 4%). A significant difference in the mean measured vessel diameter at the two different temperatures was obtained (P less than 0.001 Mann Witney). We conclude that digital artery diameter can be measured using the CUTECH DM70.

The changes in the peripheral vascular response to temperature have been studied for ten menstrual cycles by calculating thermal entertainment levels. The entrainment levels exhibited peaks at around the time of ovulation, a result which we believe is due to the fluctuating levels of the hormones oestrogen and progesterone in the blood. An attempt has been made to explain the influence of these hormones on the vasomotor control system and where interactions may occur.

This study reports an investigation into the effect of shoe mass on the gait patterns of below-knee (BK) amputees. Ten established unilateral BK, patellar-tendon-bearing prosthesis wearers were assessed using a VICON system of gait analysis. Incremental masses of 50g (up to 200g) were added to the subjects' shoes and data captured as they walked along a 15m measurement field. Coefficients of symmetry of various parameters of the swing phase (knee frequency symmetry, swing time symmetry) were measured and their correlation was tested with the patient's preferred shoe mass and also their own shoe mass, all expressed as a proportion of body mass. The subjects' 'preferred' shoe mass (139-318g) showed the greatest symmetry in all the parameters examined (correlations 0.78-0.81 p less than 0.01 and less than 0.005), whereas there was no correlation between the subjects' own shoe mass (121-325g) and the symmetry coefficients measured.

A new objective test for diagnosing Raynaud's phenomenon was assessed in practice. The test is based on entrainment of the thermal vasomotor control system and entails non-invasive measurement of blood-flow responses in one hand while alternating thermal stimuli are applied to the contralateral hand. A significant (p less than 0.001) abnormality of vasomotor control was found in patients with Raynaud's phenomenon compared with normal subjects. When applied clinically this test is diagnostic and indicates the severity of the disease and the effect of treatment.

Regional blood flow in the areola was measured by using the non-invasive transient thermal clearance method in normal breasts and in breasts involved with cancer. Areolar blood flow (ABF) in normal breasts was almost constant for women in the age range 20-60y, but decreased at higher ages. ABF in breasts involved with cancer was higher than that in the contralateral breast, and higher than the average normal ABF in the corresponding age group. The effect was more prominent in the left breast. The transient thermal clearance method provides a potential non-invasive means for detection of breast cancer.

From an examination of the factors affecting the diagnostic accuracy of the 125I-fibrinogen test for detecting deep vein thrombosis it is concluded that there is a greater possibility of error if postoperative counts are referred to the preoperative baseline rather than counts made immediately after operation. A method is proposed for reducing other errors caused by instrument mishandling.

The ankle/brachial blood pressure index (A/B PI) is important in the vascular laboratory assessment of peripheral vascular disease. However it is falsely elevated in diabetes, hence underestimating the true severity of disease. We have therefore examined the influence of diabetes on the A/B PI in 2092 patients, 538 with diabetes, all referred for evaluation of peripheral vascular disease. The prevalence of a raised A/B PI (greater than or equal to 1.5) in insulin-treated patients (18.3%) was much higher (p less than 0.001) than that in both non-insulin-treated diabetic patients (4.5%) and patients with no diabetes (2.8%). Insulin-treated patients with a duration of diabetes of greater than 30 years had a higher prevalence of raised A/B PI than those with a duration of less than or equal to 9 years. No significant age effects were seen.

One hundred thirty-nine patients with invasive carcinoma of the cervix underwent laparotomy at the University of South Florida between February 1980 and November 1983. One hundred nineteen had laparotomy prior to treatment and 20 after treatment for recurrence or some other reason. One hundred twenty patients had negative peritoneal cytology, 8 had equivocal cytology and 11 had positive cytology. Positive peritoneal cytology was more common in higher-stage disease and was statistically significantly more common in patients with positive retroperitoneal lymph nodes (P less than 0.05). The rate of peritoneal cytologic positivity in patients with squamous carcinoma was the same as that for adenocarcinoma and adenosquamous carcinoma. Positive peritoneal cytology was associated with a very poor prognosis but was associated with other poor prognostic factors in all but 1 patient. Equivocal cytology did not seem to be of any particular significance. No patient in this series had an alteration in treatment planning based on peritoneal cytology. The utility and future of peritoneal cytology in invasive carcinoma of the cervix are discussed.

The possible benefits of adding a low-dose heparin regimen to the technique of peroperative intermittent calf compression for preventing deep vein thrombosis (D.V.T.) were assessed in a randomized trial in 84 surgical patients. The efficacy of peroperative intermittent calf compression was not enhanced by a low-dose heparin regimen, but neither was it worsened. Age, weight, duration, operation, and malignant disease did not affect the relative effectiveness of the two regimens of prophylaxis. The results confirmed that venous stasis is the principal cause of D.V.T.

Analysis of the instantaneous peak velocity waveform obtained from the common femoral artery can be used to provide an objective assessment of arterial disease in the leg. The calculation of waveform indices pulsatility index and rise time together with principal component analysis has been found to be the ideal method by which to assess the flow data on-line.

The response of the systolic pressure in the pedal arteries to the stress of exercise is one of several ways of assessing the severity of peripheral vascular disease. We have examined 2607 such pressure response curves in an attempt to produce a simple method of response classification. Regression analysis of the curves has shown that errors are least when the regression used is the same order as the number of data points. We conclude that post exercise response curves can be adequately classified from three data points, one obtained within two minutes of the cessation of exercise, a second obtained between 4 and 6 minutes from the end of exercise and a third taken 10 minutes after exercise. The use of a response curve indexed to systemic systolic pressure was not found to produce a better correlation between full and three point curves, though the absolute classification differed slightly from that obtained from the non-indexed curve. Neither classification system proved significantly superior in relating to the degree of arterial disease.

Accurate and objective assessment of amputation level in the lower limb plays an important role in patient management. Laser Doppler flowmetry (LDF) is a new and noninvasive technique for skin blood flow measurement and has been used pre-operatively in 25 patients undergoing amputation for vascular disease and in five normal controls. Baseline flux measurements were made at room temperature on the medial aspect of legs and then again after local heating of the skin for five minutes. Transcutaneous oxygen measurements were made at the same site for comparison and amputation level in patients selected on this basis. Significant differences (p less than 0.001) in TcPO2 values were found between controls (10.9 +/- 0.5 kPa), below-knee (BK) amputees (6.0 +/- 1.5 kPa) and above-knee (AK) amputees (1.5 +/- 0.6 kPa). Baseline LDF flux did not differ significantly between any group. Heated flux values did however show a significant difference (p less than 0.005) between controls (52.4 +/- 23.5) and both BK (20.6 +/- 9.2) and AK groups (8.1 +/- 7.7) and also between the amputee groups. The relative increase in flux (heated flux/baseline flux) differed significantly between the BK (3.3 +/- 1.5) and AK (1.2 +/- 0.3) groups (p less than 0.001) and between these two and the controls (11.2 +/- 5.4) (p less than 0.001). The correlation between relative increase in flux and TcPO2 was 0.7 (p less than 0.001). It is concluded that laser Doppler flowmetry used in conjunction with thermal stressing could provide a quick, simple and non-invasive method for objectively determining amputation level in the lower limb.

Over a 6-year period 64 axillofemoral bypass and femorofemoral crossover grafts have been performed in 58 patients, most of whom were considered unfit for intra-abdominal surgery. Indications were peripheral ischaemia in 78 per cent and disabling claudication in 22 per cent. The limb salvage rate at 3 years was 75 per cent. No claudicants lost limbs, but only one-third of patients presenting with forefoot gangrene or ulceration avoided amputation. Most patients presenting with ischaemic symptoms at rest had associated femoropopliteal and distal disease, confirmed by the ankle pressure index measurements, and this influenced graft patency. Although the cumulative patency at 3 years for all grafts combined was 57 per cent with similar patencies for both the axillofemoral and femorofemoral grafts, early occlusion was more common in axillofemoral grafts and this may be reduced in bifemoral grafts by the increased flow rate in the vertical limbs. Peroperative electromagnetic flowmeter measurements were made after reconstruction on 55 femoral arteries in 46 of the patients and graft flow velocities were derived from these measurements. Comparison between velocities from those grafts remaining patent and those subsequently occluding showed a high incidence of occlusion in grafts with a maximal velocity after distal vasodilatation of less than 8 cm/s. Graft occlusion after the first postoperative month was more commonly associated with other factors such as continued smoking, severity of distal disease and perigraft infection.

This paper reports a study carried out in 200 patients to assess the effectiveness of a clinical vascular laboratory in the routine assessment of peripheral vascular disease (PVD) of the lower limb. Laboratory assessments involved a computer based hierarchical testing system incorporating pedal pressure indices, maximum walking distances and principal component analysis of the common femoral artery blood velocity waveform. The study fell into two parts. In the first, the laboratory assessments of 100 patients referred six years ago were compared retrospectively with their eventual clinical outcome. In this comparison, the laboratory provided a "diagnosis" which was 79% correct. In the second, a double blind prospective study was carried out in 100 patients to compare the vascular laboratory "diagnosis" with the diagnosis and prognosis of a skilled clinician, the outcome being compared one year after the initial assessment. In this study the laboratory proved to be correct in 78% of cases, the clinician in 70%. With a slightly modified computer protocol for the non vascular diagnosis, the computer would have been correct in 85% of cases. This test provides a quantitative and objective assessment of PVD which can assist in the patient's clinical diagnosis and management.

In a group of 47 patients with Raynaud's phenomenon, Doppler ultrasound velocimetry was used to establish the severity of the disease by detecting the patency of the digital arteries. In conjunction with small digital occlusion cuffs, digital artery systolic pressure was measured on either side of the finger. A significant variation in systolic pressure was detected in each finger, and on each side of individual fingers. A more sensitive index of the severity of the disease was noted when the digital systolic pressure was compared to the brachial systolic pressure. Plasma exchange, a potent method of lowering whole blood viscosity and plasma fibrinogen, was used to treat 18 of these patients. There was a significant improvement in digital vessel patency at both 21 degrees C and 13 degrees C after plasma exchange. Both the digital artery systolic pressure and the pressure index improved significantly after treatment.

A prospective study has been undertaken on 24 patients to establish the relationship between the degree of internal carotid artery stenosis, as estimated by arteriography, and the pulse wave transit time in the carotid artery. The technique involves the simultaneous use of two continuous wave Doppler velocimeters, one on the carotid and one on the supraorbital artery, to measure the flow waves and hence deduce the pulse wave transit times. The measured transit times varied from 17 to 124 ms with a beat-to-beat variation of 11 per cent. The absolute transit time in any segment correlated moderately well with the estimated degree of stenosis (r = 0.68, P less than 0.001). However, normalization of the transit times, to correct for the effects of blood pressure and age, produced on improved correlation between the variables (r = 0.8, P less than 0.001). Normalization was achieved by dividing the common carotid to supraorbital transit time by the shortest transit time found between the common carotid and either the superficial temporal or brachial arteries. Significant differences in the normalized transit times were found between arteries that were diametrically stenosed by more than 50 per cent, by between 21 and 50 per cent and by 20 per cent or below. It is concluded that pulse wave transit time measurement can provide a simple and reproducible non-invasive technique for the diagnosis of varying degrees of carotid artery stenosis.

1. Raynaud's phenomenon is a condition which primarily affects women and it must be assumed that hormonal influences are responsible. 2. To further investigate this assumption the effect of cyclic sex hormone fluctuations on the digital vascular reactivity of ten normal young women was studied by the diagnostic techniques of thermal entrainment of finger blood flow and Doppler ultrasound mapping of the digital arteries. 3. In the immediate pre-ovulatory period the results obtained were comparable with those found in patients with established Raynaud's phenomenon, suggesting that oestrogen has an important modulating effect in vivo on reflex peripheral vasomotor responses to thermal stimuli. 4. 'Primary' Raynaud's phenomenon may represent an exaggerated response to oestrogen.