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Background: Despite an unparalleled global refugee crisis, there are almost no studies in primary care addressing real-world conditions and longer courses of treatment that are typical when resettled refugees present to their physician with critical psychosocial needs and complex symptoms. We studied the effects of a year of psychotherapy and case management in a primary care setting on common symptoms and functioning for Karen refugees (a newly arrived population in St Paul, Minnesota) with depression., Methods: A pragmatic parallel-group randomized control trial was conducted at two primary care clinics with large resettled Karen refugee patient populations, with simple random allocation to 1 year of either: (1) intensive psychotherapy and case management (IPCM), or (2) care-as-usual (CAU). Eligibility criteria included Major Depression diagnosis determined by structured diagnostic clinical interview, Karen refugee, ages 18-65. IPCM (n = 112) received a year of psychotherapy and case management coordinated onsite between the case manager, psychotherapist, and primary care providers; CAU (n = 102) received care-as-usual from their primary care clinic, including behavioral health referrals and/or brief onsite interventions. Blinded assessors collected outcomes of mean changes in depression and anxiety symptoms (measured by Hopkins Symptom Checklist-25), PTSD symptoms (Posttraumatic Diagnostic Scale), pain (internally developed 5-item Pain Scale), and social functioning (internally developed 37-item instrument standardized on refugees) at baseline, 3, 6 and 12 months. After propensity score matching, data were analyzed with the intention-to-treat principle using repeated measures ANOVA with partial eta-squared estimates of effect size., Results: Of 214 participants, 193 completed a baseline and follow up assessment (90.2%). IPCM patients showed significant improvements in depression, PTSD, anxiety, and pain symptoms and in social functioning at all time points, with magnitude of improvement increasing over time. CAU patients did not show significant improvements. The largest mean differences observed between groups were in depression (difference, 5.5, 95% CI, 3.9 to 7.1, P < .001) and basic needs/safety (difference, 5.4, 95% CI, 3.8 to 7.0, P < .001)., Conclusions: Adult Karen refugees with depression benefited from intensive psychotherapy and case management coordinated and delivered under usual conditions in primary care. Intervention effects strengthened at each interval, suggesting robust recovery is possible., Trial Registration: clinicaltrials.gov Identifier: NCT03788408. Registered 20 Dec 2018. Retrospectively registered.

We implemented direct collocation on a full-body neuromusculoskeletal model to calculate muscle forces, ground reaction forces and knee contact loading simultaneously for one cycle of human gait. A data-tracking collocation problem was solved for walking at the normal speed to establish the practicality of incorporating a 3D model of articular contact and a model of foot-ground interaction explicitly in a dynamic optimization simulation. The data-tracking solution then was used as an initial guess to solve predictive collocation problems, where novel patterns of movement were generated for walking at slow and fast speeds, independent of experimental data. The data-tracking solutions accurately reproduced joint motion, ground forces and knee contact loads measured for two total knee arthroplasty patients walking at their preferred speeds. RMS errors in joint kinematics were < 2.0° for rotations and < 0.3 cm for translations while errors in the model-computed ground-reaction and knee-contact forces were < 0.07 BW and < 0.4 BW, respectively. The predictive solutions were also consistent with joint kinematics, ground forces, knee contact loads and muscle activation patterns measured for slow and fast walking. The results demonstrate the feasibility of performing computationally-efficient, predictive, dynamic optimization simulations of movement using full-body, muscle-actuated models with realistic representations of joint function.

In the "Materials and Methods" section, the link provided at the bottom of the second paragraph should be https://simtk.org/home/dcwithjtcontact/ .

The aim of this study was to perform multi-body, muscle-driven, forward-dynamics simulations of human gait using a 6-degree-of-freedom (6-DOF) model of the knee in tandem with a surrogate model of articular contact and force control. A forward-dynamics simulation incorporating position, velocity and contact force-feedback control (FFC) was used to track full-body motion capture data recorded for multiple trials of level walking and stair descent performed by two individuals with instrumented knee implants. Tibiofemoral contact force errors for FFC were compared against those obtained from a standard computed muscle control algorithm (CMC) with a 6-DOF knee contact model (CMC6); CMC with a 1-DOF translating hinge-knee model (CMC1); and static optimization with a 1-DOF translating hinge-knee model (SO). Tibiofemoral joint loads predicted by FFC and CMC6 were comparable for level walking, however FFC produced more accurate results for stair descent. SO yielded reasonable predictions of joint contact loading for level walking but significant differences between model and experiment were observed for stair descent. CMC1 produced the least accurate predictions of tibiofemoral contact loads for both tasks. Our findings suggest that reliable estimates of knee-joint loading may be obtained by incorporating position, velocity and force-feedback control with a multi-DOF model of joint contact in a forward-dynamics simulation of gait., (Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.)

Inverse dynamics analysis is commonly used to estimate the net loads at a joint during human motion. Most lower-limb models of movement represent the knee as a simple hinge joint when calculating muscle forces. This approach is limited because it neglects the contributions from tibiofemoral joint contact forces and may therefore lead to errors in estimated muscle forces. The aim of this study was to quantify the contributions of tibiofemoral joint contact loads to the net knee loads calculated from inverse dynamics for multiple subjects and multiple gait patterns. Tibiofemoral joint contact loads were measured in four subjects with instrumented implants as each subject walked at their preferred speed (normal gait) and performed prescribed gait modifications designed to treat medial knee osteoarthritis. Tibiofemoral contact loads contributed substantially to the net knee extension and knee adduction moments in normal gait with mean values of 16% and 54%, respectively. These findings suggest that knee-contact kinematics and loads should be included in lower-limb models of movement for more accurate determination of muscle forces. The results of this study may be used to guide the development of more realistic lower-limb models that account for the effects of tibiofemoral joint contact at the knee., (© 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

The ability to predict patient-specific joint contact and muscle forces accurately could improve the treatment of walking-related disorders. Muscle synergy analysis, which decomposes a large number of muscle electromyographic (EMG) signals into a small number of synergy control signals, could reduce the dimensionality and thus redundancy of the muscle and contact force prediction process. This study investigated whether use of subject-specific synergy controls can improve optimization prediction of knee contact forces during walking. To generate the predictions, we performed mixed dynamic muscle force optimizations (i.e., inverse skeletal dynamics with forward muscle activation and contraction dynamics) using data collected from a subject implanted with a force-measuring knee replacement. Twelve optimization problems (three cases with four subcases each) that minimized the sum of squares of muscle excitations were formulated to investigate how synergy controls affect knee contact force predictions. The three cases were: (1) Calibrate+Match where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously matched, (2) Precalibrate+Predict where experimental knee contact forces were predicted using precalibrated muscle model parameters values from the first case, and (3) Calibrate+Predict where muscle model parameter values were calibrated and experimental knee contact forces were simultaneously predicted, all while matching inverse dynamic loads at the hip, knee, and ankle. The four subcases used either 44 independent controls or five synergy controls with and without EMG shape tracking. For the Calibrate+Match case, all four subcases closely reproduced the measured medial and lateral knee contact forces (R2 ≥ 0.94, root-mean-square (RMS) error &lt; 66 N), indicating sufficient model fidelity for contact force prediction. For the Precalibrate+Predict and Calibrate+Predict cases, synergy controls yielded better contact force predictions (0.61 &lt; R2 &lt; 0.90, 83 N &lt; RMS error &lt; 161 N) than did independent controls (-0.15 &lt; R2 &lt; 0.79, 124 N &lt; RMS error &lt; 343 N) for corresponding subcases. For independent controls, contact force predictions improved when precalibrated model parameter values or EMG shape tracking was used. For synergy controls, contact force predictions were relatively insensitive to how model parameter values were calibrated, while EMG shape tracking made lateral (but not medial) contact force predictions worse. For the subject and optimization cost function analyzed in this study, use of subject-specific synergy controls improved the accuracy of knee contact force predictions, especially for lateral contact force when EMG shape tracking was omitted, and reduced prediction sensitivity to uncertainties in muscle model parameter values.

Excessive contact force is believed to contribute to the development of medial compartment knee osteoarthritis. The external knee adduction moment (KAM) has been identified as a surrogate measure for medial contact force during gait, with an abnormally large peak value being linked to increased pain and rate of disease progression. This study used in vivo gait data collected from a subject with a force-measuring knee implant to assess whether KAM decreases accurately predict corresponding decreases in medial contact force. Changes in both quantities generated via gait modification were analyzed statistically relative to the subject's normal gait. The two gait modifications were a "medial thrust" gait involving knee medialization during stance phase and a "walking pole" gait involving use of bilateral walking poles. Reductions in the first (largest) peak of the KAM (32-33%) did not correspond to reductions in the first peak of the medial contact force. In contrast, reductions in the second peak and angular impulse of the KAM (15-47%) corresponded to reductions in the second peak and impulse of the medial contact force (12-42%). Calculated reductions in both KAM peaks were highly sensitive to rotation of the shank reference frame about the superior-inferior axis of the shank. Both peaks of medial contact force were best predicted by a combination of peak values of the external KAM and peak absolute values of the external knee flexion moment (R(2) = 0.93). Future studies that evaluate the effectiveness of gait modifications for offloading the medial compartment of the knee should consider the combined effect of these two knee moments., (Published by Wiley Periodicals, Inc. J Orthop Res 28:1348-1354, 2010.)

Musculoskeletal models are currently the primary means for estimating in vivo muscle and contact forces in the knee during gait. These models typically couple a dynamic skeletal model with individual muscle models but rarely include articular contact models due to their high computational cost. This study evaluates a novel method for predicting muscle and contact forces simultaneously in the knee during gait. The method utilizes a 12 degree-of-freedom knee model (femur, tibia, and patella) combining muscle, articular contact, and dynamic skeletal models. Eight static optimization problems were formulated using two cost functions (one based on muscle activations and one based on contact forces) and four constraints sets (each composed of different combinations of inverse dynamic loads). The estimated muscle and contact forces were evaluated using in vivo tibial contact force data collected from a patient with a force-measuring knee implant. When the eight optimization problems were solved with added constraints to match the in vivo contact force measurements, root-mean-square errors in predicted contact forces were less than 10 N. Furthermore, muscle and patellar contact forces predicted by the two cost functions became more similar as more inverse dynamic loads were used as constraints. When the contact force constraints were removed, estimated medial contact forces were similar and lateral contact forces lower in magnitude compared to measured contact forces, with estimated muscle forces being sensitive and estimated patellar contact forces relatively insensitive to the choice of cost function and constraint set. These results suggest that optimization problem formulation coupled with knee model complexity can significantly affect predicted muscle and contact forces in the knee during gait. Further research using a complete lower limb model is needed to assess the importance of this finding to the muscle and contact force estimation process., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

Musculoskeletal modeling and optimization theory are often used to determine muscle forces in vivo. However, convincing quantitative evaluation of these predictions has been limited to date. The present study evaluated model predictions of knee muscle forces during walking using in vivo measurements of joint contact loading acquired from an instrumented implant. Joint motion, ground reaction force, and tibial contact force data were recorded simultaneously from a single subject walking at slow, normal, and fast speeds. The body was modeled as an 8-segment, 21-degree-of-freedom articulated linkage, actuated by 58 muscles. Joint moments obtained from inverse dynamics were decomposed into leg-muscle forces by solving an optimization problem that minimized the sum of the squares of the muscle activations. The predicted knee muscle forces were input into a 3D knee implant contact model to calculate tibial contact forces. Calculated and measured tibial contact forces were in good agreement for all three walking speeds. The average RMS errors for the medial, lateral, and total contact forces over the entire gait cycle and across all trials were 140 +/- 40 N, 115 +/- 32 N, and 183 +/- 45 N, respectively. Muscle coordination predicted by the model was also consistent with EMG measurements reported for normal walking. The combined experimental and modeling approach used in this study provides a quantitative framework for evaluating model predictions of muscle forces in human movement., ((c) 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

Selected beef subprimals were obtained from fabrication lines of three foodservice purveyors to assist in the development of a software support program for the beef foodservice industry. Subprimals were fabricated into bone-in or boneless foodservice ready-to-cook portion-sized cuts and associated components by professional meat cutters. Each subprimal was cut to generate mean foodservice cutting yields and labor requirements, which were calculated from observed weights (kilograms) and processing times (seconds). Once fabrication was completed, data were analyzed to determine means and standard errors of percentage yields and processing times for each subprimal. Subprimals cut to only one end point were evaluated for mean foodservice yields and processing times, but no comparisons were made within subprimal. However, those traditionally cut into various end points were additionally compared by cutting style. Subprimals cut by a single cutting style included rib, roast-ready; ribeye roll, lip-on, bone-in; brisket, deckle-off, boneless; top (inside) round; and bottom sirloin butt, flap, boneless. Subprimals cut into multiple end points or styles included ribeye, lip-on; top sirloin, cap; tenderloin butt, defatted; shortloin, short-cut; strip loin, boneless; top sirloin butt, boneless; and tenderloin, full, side muscle on, defatted. Mean yields of portion cuts, and mean fabrication times required to manufacture these cuts differed (P < 0.05) by cutting specification of the final product. In general, as the target portion size of fabricated steaks decreased, the mean number of steaks derived from any given subprimal cut increased, causing total foodservice yield to decrease and total processing time to increase. Therefore, an inverse relationship tended to exist between processing times and foodservice yields. With a method of accurately evaluating various beef purchase options, such as traditional commodity subprimals, closely trimmed subprimals, and pre-cut portion steaks in terms of yield and labor cost, foodservice operators will be better equipped to decide what option is more viable for their operation.

Twenty-nine selected styles of subprimals or sections of veal were obtained from a commercial facility to assist in the development of a support program for retailers. They were fabricated into bone-in or boneless retail cuts and associated components by trained meat cutters. Each style selected (n = 6) was used to generate mean retail yields and labor requirements, which were calculated from wholesale and retail weights and processing times. Means and standard errors for veal ribs consisting of five different styles (n = 30) concluded that style #2, 7-rib 4 (10 cm) x 4 (10 cm), had the lowest percentage of total retail yield (P < .05) owing to the greatest percentage of bone. Furthermore, rib style #2 required the longest total processing time (P < .05). Rib styles #3, 7-rib chop-ready, and #5, 6-rib chop ready, yielded the greatest percentage of total retail yield and also had the shortest total processing time (P < .05). Within veal loins, style #2, 4 (10 cm) x 4 (10 cm) loin kidney fat in, had the greatest percentage fat (P < .05). Loin styles #2 and #3, 4 (10 cm) x 4 (10 cm) loin special trimmed, generated more lean and fat trimmings and bone, resulting in lower percentage of total retail yields than loin style #1, 0 (0 cm) x 1 (2.5 cm) loin special trimmed (P < .05). Results indicated that bone-in subprimals and sections required more processing time if fabricated into a boneless end point. In addition, as the number of different retail cuts increased, processing times also increased.

Lamb carcasses (n = 94) from five packing plants, selected to vary in weight class and fat thickness, were used to determine retail yield and labor requirements of wholesale lamb fabrication. Carcasses were allotted randomly according to weight class to be fabricated as whole carcasses (n = 20), three-piece boxes (n = 22), or subprimals (n = 52). Processing times (seconds) were recorded and wholesale and retail weights (kilograms) were obtained to calculate retail yield. Subprimals were fabricated into bone-in retail cuts or boneless or semi-boneless retail cuts. Retail yield for subprimal lamb legs decreased from 85.3 +/- .6% for bone-in to 68.0 +/- .7% for a completely boneless retail product. Correspondingly, processing times increased from 126.1 +/- 5.4 s to 542.0 +/- 19.2 s for bone-in and boneless legs, respectively. For all subprimals, retail yield percentage tended to decrease and total processing time increase as cuts were fabricated to boneless or semi-boneless end points compared with a bone-in end point. Percentage retail yield did not differ (P > .05) among whole carcass, three-piece box, and subprimal marketing methods. Total processing time was shorter for subprimals (P < .05) than for the other two marketing methods.

Boxed pork was obtained to represent four different purchase specifications (different anatomical separation locations and[or] external fat trim levels) common in the pork industry to conduct a study of retail yields and labor requirements. Bone-in loins (n = 180), boneless loins (n = 94), and Boston butts (n = 148) were assigned randomly to fabrication styles within subprimals. When comparing cutting styles within subprimals, it was evident that cutting style affected percentage of retail yield and cutting time. When more bone-in cuts were prepared from bone-in loin subprimals, retail yields ranged from 92.80 +/- .61 to 95.28 +/- .45%, and processing times ranged from 222.57 +/- 10.13 to 318.99 +/- 7.85 s, from the four suppliers. When more boneless cuts were prepared from bone-in loin subprimals, retail yields ranged from 71.12 +/- 1.10 to 77.92 +/- .77% and processing times ranged from 453.49 +/- 8.95 to 631.09 +/- 15.04 s from the different loins. Comparing boneless to bone-in cuts from bone-in loins resulted in lower yields and required greater processing times. Significant variations in yields and times were found within cutting styles. These differences seemed to have been the result of variation in supplier fat trim level and anatomical separation (primarily scribe length).

To assess retail value and profitability, cutting test data were obtained in a simulated retail cutting room for boxed pork subprimals, bone-in loins (n = 180), boneless loins (n = 94), Boston butts (n = 148), fresh hams (n = 28), and boneless hams (n = 23). Processing times (seconds) and retail weights (kilograms) were used to determine relative value. Cutting style affected (P < .05) value differential (US$/subprimal) for bone-in and boneless loins. When cutting styles within subprimals were pooled, value differential was affected (P < .05) by purchasing specification for bone-in loins, boneless loins, Boston butts, and inside fresh hams. Processing bone-in loins to a boneless end point produced a greater (P < .05) value differential and percentage of gross margin than a bone-in retail end point. Bone-in loins fabricated to a boneless retail end point produced a greater (P < .05) value differential and percentage of gross margin than boneless loins fabricated to the same end point. The increase in retail value can be attributed to the increased number and weight of retail cuts produced from bone-in loins. The thick, boneless loin cutting style produced a greater (P < .05) value differential and percentage of gross margin as a result of a lower (P < .05) cost of fabrication and increased value of retail cuts than the thin, boneless cutting style. In general, boneless pork cutting methods were more profitable than bone-in cutting methods regardless of subprimal.

A model was developed for the economic evaluation of embryos for producing bull lines for use in commercial beef production. The fundamental concept underlying the model is that a cloned and sexed embryo of known genetic characteristics for beef traits is used to produce a bull. After reaching physiological maturity, the bull is used in natural matings. Equations relating feed energy requirements and growth rates based on NRC requirements and costs and returns discounted to present value allow investigation of expected economic merits of progeny from different embryo bull lines. The model has the flexibility to determine optimal embryo characteristics for different production environments. Model sensitivity to variation in progeny sex ratios, growth rates, yield and quality grades, and herd fertility characteristics was examined. Net present values (NPV) per embryo transferred were determined at the optimal marketing age of progeny produced from mating the bull to 30 cows per year for 5 yr. Relative to the lowest NPV of $18,209 for progeny with an expected quality grade of Select and yield grade of 4 at 400 d, increments in NPV ranged from $329 to $22,708 depending on differences in expected progeny carcass grade characteristics. The difference between NPV for 100% male and 40% male sex ratios was $7,518. The NPV differences between progeny growth rates of 1.6 and .9 kg/d holding herd conception rate constant at .9 and .5 were $8,311 and $4,611, respectively. The model evaluates relative economic values of embryo lines for producing bulls, accommodating interactions among progeny characteristics, and environments.

Concepts used to derive a deterministic model for evaluating embryo transfer for commercial steer production taking into consideration genetic merit for growth and mature size, herd feed supply, and recipient maternal environment are discussed. Genetic potential of an embryo is used to derive optimal growth rates that can be sustained by available herd feed per animal per day. Equations are provided for various measures of performance as functions of the feed, genotype of the embryo, and recipient maternal contribution. To assess the value of a particular line of embryos, interactions between genotype and nutrient environment are quantified, so that the benefits of embryos of high genetic merit are evaluated objectively. Product quality and weight are predicted from the model to provide a framework that will allow commercial beef producers to determine marketing strategies likely to result in optimal return.

Twenty-five patients with FIGO clinical Stages IB-IVA squamous cancers of the uterine cervix underwent pelvic magnetic resonance imaging to assist in the design of radiation therapy portals. Magnetic resonance imaging was used primarily to define the treatment volume required to encompass the primary disease and its direct regional extensions, and only secondarily to assess the presence or absence of lymph node metastases. The sagittal scans revealed that use of "conventional" or "standard" lateral radiation portals would have resulted in a failure to encompass all gross cancer extensions (marginal miss) in 6 patients (24%). The beam edge of standard portals would have traversed tissue within 1 cm or less of gross cancer in an additional 8 patients (32%), increasing the risk of regional underdosage of subclinical disease extensions. Use of conventional lateral portals would have resulted in incomplete coverage of the uterine fundus in 15 of 24 patients (62.5%), of whom 3 had gross cancer extension to involve the uterine cavity or the myometrium of the lower uterine segment. Conventional lateral portal design, as described and illustrated in standard radiation oncology texts, may be suboptimal for a significant percentage of patients with locally advanced or bulky cervical cancer, and could be a contributing cause of failure to control pelvic disease. Design of lateral treatment portals should be based on imaging the morbid anatomy in the treatment position, rather than on an assumption of normal anatomic relationships.

A new approach to the assessment of breast health was developed based upon continuous ambulatory recording of breast temperature for 24 hrs. A new data acquisition system consisting of a portable, multi-channel, microprocessor-based recorder worn on a belt was developed to record temperatures. Dramatic thermal fluctuations were noted during the recordings in response to multiple stimuli (physiological, behavioral, environmental). Specific algorithms and software programs were developed to process the thermobiologic and chronobiologic information. Data processing was fully automatic and included an examination report indicating a score and a chronothermodynamic class for each of the five areas examined on each breast. The preliminary clinical studies have concerned more than 450 patients with healthy or diseased breasts.

Two cases of haemorrhagic renal cyst presenting in the neonatal period are described. Ultrasound examination, excretory urogram, and MRI, gave diagnosis in the second case. The remarkable histopathologic pattern of these two cases has led to propose correct diagnosis of pure cystic mesoblastic nephroma, an unusual variety of mesoblastic nephroma.

A four-year prospective study was conducted on more than 25,000 women, both asymptomatic (59%) and symptomatic (41%), with a view to investigating the thermal and vascular disorders associated with early stages of breast malignancy. All the patients underwent thermographic, mammographic and physical examinations performed under standard conditions and, when indicated, complementary radiographic (spot/magnified pictures), ultrasound and cytologic tests. Of the 294 in situ, microinvasive and nonpalpable cancers diagnosed in this study, 60-70% generated significant thermal anomalies that, in most cases, consisted of distorted thermovascular patterns. A tentative explanation for these clinical observations was formed from intramammary measurements of temperature and blood flow performed on seven patients and was based on recent experimental data on the origin of vascular reactions associated with cancer growth. This study clearly showed that thermography may contribute to the early detection of breast cancer and to the identification of women at high risk of developing breast cancer. Two hundred four (21.3%) of the 958 patients who, on their first visit, had an abnormal thermogram but no findings at physical examination or mammography developed cancer within the next three years (length of follow-up, 4-41 months).

The prenatal sonographic findings in 10 infants with omphalocele or gastroschisis diagnosed either by sonogram or by physical examination at birth are reviewed. There were six true-positive diagnoses, as well as two false-positive and two false-negative diagnoses by sonography. The false-positive cases resulted from confusion of umbilical cord with extruded bowel (1 case) and oligohydramnios coupled with improper scanning technique (1 case). The false-negative cases resulted from poor documentation of fetal anatomy (1 case) and confusion of extruded bowel with umbilical cord (1 case). These pitfalls may be avoided by using optimal scanning technique with documentation of fetal anatomy and pulsed Doppler sonography.

A Chi-square test of goodness of fit indicated that many Guernsey sires had mates not representative of the population. Mates effect on sire ranking by progeny records, therefore, was examined for each of 12 traits of body conformation. Sire rankings from two models including a random sire factor and fixed age, month, and herd-year factors were compared. One model contained dam's score as a covariate. Eighty sires having 33,634 daughters with first scores were in the analysis. Addition of mate's score as a covariate did not change appreciably sire ranking when all progeny were included. For the 12 traits, Spearman's rank correlations were in excess of .99.

Percutaneous aspiration of the gallbladder was performed for nine hospitalized patients, most commonly to establish the diagnosis of acute cholecystitis and its complications in the critically ill patient or patient with sepsis. In five patients, aspiration alone was performed; in four, permanent percutaneous catheter drainage followed diagnostic aspiration. Ultrasonic guidance was used, and aspiration/drainage was performed at bedside for seven of the patients.

Eight pregnancies with open neural tube defects were detected in 70 midtrimester patients referred for sonography and amniocentesis because of elevated maternal serum alpha-fetoprotein levels. Two cases of anencephaly were detected by sonography, aborted without amniocentesis, and confirmed by pathologic examination. Six cases of open spina bifida were detected through amniocentesis by elevation of alpha-fetoprotein and acetylcholinesterase levels. In only three of these six was the abnormality seen on sonography. All six pregnancies were terminated, and open spina bifida defects were confirmed on pathologic examination. Amniocentesis was 100% sensitive for diagnosis of open spina bifida, while sonography was only 50% sensitive. Our results indicate that, in patients with elevated serum alpha-fetoprotein and a normal fetal sonogram, amniocentesis should be performed to rule out open spina bifida.

The recurrence of a benign mediastinal bronchogenic cyst 20 years after partial excision precipitated potentially serious vascular and pulmonary complications. Aggressive total surgical excision should be feasible in the majority of cases. An approach via a median sternotomy offers distinct advantages in certain cases and should be considered. Computerized axial tomographic scanning promises to provide improved definition of mediastinal anatomic features and should be a valuable noninvasive diagnostic method in selected cases.

One hundred and two aspiration or drainage procedures were reviewed to determine the value of portable sonographic and real-time needle guidance systems. While the majority of thoracenteses or abdominal paracenteses were performed without the aid of real-time guidance, these systems were instrumental in the development of new procedures such as percutaneous cholecystostomy and in the drainage of small fluid collections in critical areas. Portable sonographic guidance was used in 32 cases, mostly for thoracentesis or abdominal paracentesis, but it had its greatest value in guiding drainage procedures at the bedside in critically ill patients. These portable drainage procedures included four cholecystostomies, one nephrostomy, drainage of two abdominal abscesses, and two empyema drainages. Complications included one case of an enterocutaneous fistula and one case of hemoptysis after thoracentesis. The failure rate was less than 7%. The use of portable real-time sonographic and needle-guidance systems has a direct impact on improving patient care.

Arthrography using an opaque medium to explore the shoulder in two cases demonstrated rupture of the rotator muscles sheath associated with a communication into the acromioclavicular joint. Rupture of the sheath allows direct contact between the humeral head and the capsule of the acromioclavicular joint which becomes eroded progressively. Recent studies have produced data indicating participation of the acromioclavicular joint in the natural history of deteriation of the sheath of the rotator muscles.

The role of ultrasonography in the imaging of superficially located structures is enhanced by the appropriate application of basic physical principles. Emphasis is placed on the understanding of axial and lateral resolution, variable and dynamic focusing systems, and fluid-path scanners. Knowledge of these principles is useful in daily practice and in the evaluation of new equipment.

A method for the evaluation of regional lung ventilation using 81mKr eluted from a rubidium generator is described. The tracer distribution at equilibrium is a function of regional ventilation, not of volumes. The study can be performed on a wide range of patients, including unconscious and mechanically ventilated patients, and can be performed immediately following or concurrently with a perfusion study. Thus, precisely comparable ventilation and perfusion images can be obtained.