A controlled study of brain magnetic resonance imaging in patients with the chronic fatigue syndrome

Two neuroradiologists compared the brain MR scans of 52 patients with the CDC criteria for the chronic fatigue syndrome (CFS) with those of 52 age and sex matched controls who had undergone imaging because of histories of head trauma or headache. CFS patients had significantly more abnormal scans than controls--27% vs 2%. Abnormalities seen were foci of increased white matter T2 signal in 9 CFS patients and one control and ventricular or sulcal enlargement in 5 CFS patients. Follow up of patients with subcortical signal hyperintensities revealed 3 who had symptoms suggestive of other known medical causes of what appeared to be CFS. The data indicate that some CFS patients have some organic problem manifesting itself on neuroimaging. But, finding MR abnormalities should warn the physician that the patient's symptoms may be secondary to some other medical illness and not simply primary CFS.

Comparison of balloon valvuloplasty with operative treatment for mitral stenosis

To determine the optimal role for percutaneous balloon mitral valvuloplasty or open mitral commissurotomy, the outcome of 164 consecutive patients undergoing either percutaneous balloon mitral valvuloplasty, open mitral commissurotomy, or mitral valve replacement for mitral stenosis was reviewed. No preoperative differences existed between percutaneous balloon mitral valvuloplasty and open mitral commissurotomy in age, symptoms, or mitral valve characteristics. Symptoms improved similarly in all groups, and median hospital stays after procedures were 2, 9, and 10 days for percutaneous balloon mitral valvuloplasty, open mitral commissurotomy, and mitral valve replacement (p < 0.005). Actuarial survivals at 36 months did not differ significantly (83% +/- 6%, 94% +/- 4%, and 90% +/- 4%). Actuarial freedoms from subsequent mitral valve procedures at 36 months were 66% +/- 7%, 87% +/- 6%, and 100% +/- 13% (p < 0.005), with the linearized rate of subsequent mitral valve procedures being 12% +/- 3%, 4% +/- 2%, and 1.2% +/- 0.8%/patient-year for percutaneous balloon mitral valvuloplasty, open mitral commissurotomy, and mitral valve replacement (p < 0.01). Prior mitral commissurotomy increased the likelihood of subsequent mitral procedures after percutaneous balloon mitral valvuloplasty from 10% +/- 3% to 20% +/- 7%/patient-year.

Differentiation between MK-801- and apomorphine-induced stereotyped behaviors in mice

The ability of phencyclidine (PCP) to model schizophreniform psychosis is believed to be related to its ability to produce both hypoglutamatergia and hyperdopaminergia. As such, identification of PCP-stimulated behaviors may be important for the development of animal models of schizophrenia. In this study, MK-801 [(+)-5-methyl-10,11-dihydro-5H- dibenzo[a,d]cycloheptane-5,10-imine maleate], a high-affinity PCP analogue, was administered to mice in order to stimulate "PCP behaviors." These PCP behaviors were compared with behaviors stimulated by apomorphine, a dopamine agonist. Stereotyped behavior was assessed by both visual observations and automated measurements. Visual observations showed highly intense gnawing and sniffing in apomorphine-treated mice and the absence of gnawing in MK-801-treated mice. Automated stereotypic measures showed that, compared with vehicle-treated controls, there were frequent dissociations between MK-801 and apomorphine. Conceivably, a compound that attenuates PCP-stimulated behaviors while sparing apomorphine-stimulated behaviors would possess both antipsychotic efficacy and be devoid of undesirable side effects associated with dopamine blockade.

An overview of enhancement techniques for peripheral field loss

Practitioners are often reluctant to deal with impaired visual function secondary to peripheral field defects. This article presents a variety of enhancement techniques that help compensate for difficulties encountered by patients with peripheral field loss. We hope the information presented will increase practitioner awareness and help in the selection of the most appropriate treatment for the particular patient.

The utilization of a temporal mirror coating on the back surface of the lens as a field enhancement device

A 37-year-old male had a right homonymous hemianopia due to trauma. During his initial low vision assessment, a small clip-on mirror was dispensed to help him compensate for his field loss. At follow-up, he reported satisfaction with the mirror. He also reported that novelty "look behind you" sunglasses were beneficial to him and less conspicuous than the clip-on mirror. He requested temporal mirror coating on otherwise clear lenses so that he could utilize the glasses at night or on cloudy days. We fabricated this for him and also mounted a small mirror nasally within the vertex distance behind his frame. The fabrication of the two devices will be discussed as well as a comparison of these three field enhancement devices.

Propafenone-induced torsade de pointes: cross-reactivity with quinidine

A 77-year-old female with new onset atrial fibrillation occurring in the absence of structural heart disease developed torsade de pointes during therapy with quinidine bisulfate 500 mg orally every 8 hours. Ten days after quinidine therapy had been discontinued she developed torsade de pointes while receiving propafenone 300 mg orally every 8 hours. This case demonstrates that propafenone may be associated with torsade de pointes and suggests a cross-reactivity between this effect and prior occurrence of torsade de pointes on Class IA antiarrhythmic drug therapy.

A new influenza surveillance system in France: the Ile-de-France "GROG". 2. Validity of indicators (1984-1989)

The evaluation of the validity of the GROG's indicators is based on the first five years of activity, four of which being epidemic ones. A virological criterion for identifying epidemics is used as the gold standard. For each non-specific indicator, the ratio of epidemic weeks to non-epidemic weeks is outlined. Therefore we can define four epidemic situations in relation with the strains circulating and the non-specific indicators. Influenza A epidemics, which are known as a mortality problem can also be described according to its impact upon morbidity. As a result, it is possible to set up a sensitive and specific surveillance system for early detection of influenza epidemics. This objective is achieved by combining both the weekly collection of virological data as well as the collection of other available indicators either in routine practice or as provided by a network of sentinel practitioners. Such detection can pave the way for an improvement in preventive measures against the harmful effects on health of influenza epidemics.

Reading speed through different equivalent power low vision devices with identical field of view

Adequate reading speed is one of the criteria low vision patients may use to assist them when they are comparing and selecting equivalent power low vision devices. Inherently, various optical devices of equivalent power will produce different fields of view. We compared the reading speed of 32 trained, normal observers with 4 commonly prescribed types of low vision devices of +12 D equivalent power (spectacles, hand magnifier, stand magnifier, and telemicroscope) which were modified to provide nearly identical fields of view. Our results show that only the reading speed obtained with the telemicroscope was significantly different from those of the other systems (p less than 0.01). Implications are that the field of view provided by a low vision device is the primary parameter limiting reading speed of equivalent power devices.

Magnetic resonance imaging of temporomandibular joint after surgical treatment of internal derangement

Sagittal and coronal surface coil magnetic resonance imaging was performed on 21 patients who about 2 years earlier had surgery for temporomandibular joint internal derangement. Surgical procedure included disk repositioning (23 joints) and diskectomy (seven joints). At the time of reimaging, 20 joints showed recurrence of pain and 10 joints were asymptomatic. Extensive fibrous tissue was seen in the joint space and in the joint capsule in 13 of the 20 painful joints, whereas minimal fibrous tissue in the lateral capsule wall was seen in 3 of the 10 nonpainful joints. Fibrous tissue was surgically confirmed in 10 of the painful joints. Disk displacement was seen in 11 of the 23 joints that had surgical disk repositioning. Disk displacement was seen in both painful (9/17) and nonpainful joints (2/6). It was concluded that magnetic resonance imaging is an excellent method for postoperative imaging of the temporomandibular joint and that attention should be directed to the presence or absence and extension of the fibrous tissue in the joint space and in the joint capsule.

Adventitial cystic disease

Adventitial cystic disease is a rare syndrome predominantly seen in young males with the acute onset of claudication. Early diagnosis and confirmation with arteriography is of utmost importance to the success of treatment. The authors present a rare case report and treatment of adventitial cystic disease.

Comparison of reading speed in normal observers through different forms of equivalent power low vision devices

Compensation at near for vision loss can be achieved using a variety of equivalent forms of low vision magnifiers. Each has inherent advantages and disadvantages in terms of field, working distance, etc. We compared the reading speed of 60 trained, normal observers with 4 commonly prescribed types of low vision devices of +12 D equivalent power (spectacles, hand magnifier, stand magnifier, and telemicroscope) to their normal reading speed. Although there was individual variance in performance, reading speed with all the devices was generally within 20% of normal reading speed. Implications are that in terms of differences in reading speed for normals, the form of the low vision device is not as significant as acquiring proficiency in the use of the selected device.

Modification of common low vision devices for uncommon needs

Creativity in the field of low vision is certainly a necessary requisite when trying to solve a patient's individual needs. Four different categories of low vision devices--hand magnifier, stand magnifier, telescope, and absorptive lens--were modified initially to meet a particular patient's requirement(s). The devices modified were: 1) a +28 aspheric hand magnifier; 2) a magnetized stand magnifier to assist patients in stabilizing a stand magnifier; 3) a focusable telescope held on a gooseneck stand; and 4) a flip-up frame for the Corning CPF series of lenses. These modifications could be of benefit to other patients.

Lipid degeneration in a pheochromocytoma histologically mimicking an adrenal cortical tumor

A recurrent adrenal pheochromocytoma is reported in an 18-year-old woman with a family history of multiple endocrine neoplasia type IIA. The tumor was noteworthy for the presence of numerous fine intracytoplasmic lipid droplets confirmed by fat stain. Immunohistochemical studies revealed cytoplasmic positivity for chromogranin and neuron-specific enolase typical of pheochromocytoma. Electron microscopy demonstrated dense-core neurosecretory granules, in addition to the cytoplasmic lipid vacuoles. The presence of lipid within an adrenal pheochromocytoma is rare and, to our knowledge, has been documented in only one previous case report in the literature.

Combined anesthetic and surgical treatment of reflex sympathetic dystrophy following a healed crush injury of the foot

Reflex sympathetic dystrophy is an often overlooked diagnostic cause of posttraumatic pain. After wound healing, persistent pain frequently is treated with continued analgesic administration, physical therapy, acupuncture, nerve blocks, psychotherapy and sometimes even ignored in hopes that either the pain or the patient will "go away." The authors relate successful evaluation and treatment of reflex sympathetic dystrophy in the case of a young man with disabling pain following a healed crush injury to his foot.

A new influenza surveillance system in France: the Ile-de-France "GROG". 1. Principles and methodology

The aims of influenza surveillance have changed over the years. The early detection of epidemics is essential for practical decisions on vaccine development, strategy of vaccine prophylaxis, chemoprophylaxis or chemotherapy. A new surveillance system is presented which combines the classical specific data related to the isolations, direct detection of virus as well as serological findings, with non-specific indices. The rationale for definition and elaboration of such indices is discussed: selected parameters deal with medical activity of a panel of sentinel doctors (general practitioners and pediatricians), notifications of diagnosed acute respiratory viral infections, measure of emergency doctors activity, absence from work (as seen by physicians, insurance agencies or industrial personnel), selected drug prescription and consumption, hospital admissions. The sentinel physicians also cooperate in taking samples from cases, thereby extending the field of specific surveillance since they have contact with standard cases of the disease and not only hospitalized patients. A weekly comparison of time variations of specific and non-specific indices should permit a reliable evaluation of the epidemic situation and therefore be of great help for practical decisions. The system has operated since 1984, and the initial hypothesis of the sensitivity of some of the indices has already been verified.

Ileal pouch vaginal fistulas: incidence, etiology, and management

Some of the initial problems associated with the ileoanal reservoir have been solved. In their place, other complications have been recognized. Among these, the ileal pouch vaginal fistula stands out as a recently recognized difficult management problem. This multicenter study was undertaken to gain insight into the causes for, and treatment of, pouch vaginal fistulas. Cases were gathered from 11 surgical practices throughout North America, in which the ileoanal reservoir procedure is frequently performed. Overall, 304 females had undergone ileoanal reservoir procedures by these surgical groups. Twenty-one patients developed 22 pouch vaginal fistulas for an overall incidence of 6.9 percent. Five additional patients with pouch vaginal fistulas, whose restorative proctocolectomies were done elsewhere, were referred to these surgeons for treatment. The courses of these 26 patients form the basis of this report. This study details the risk factors which predispose in the development of a pouch vaginal fistula, as well as the various treatment options available.

Transient abdominal granulomas in children

Space-occupying liver lesions in febrile patients are usually caused by tumor or infection and other causes are seldom encountered. In five patients age 20 months to 12 years who were evaluated for fever of unknown origin, imaging studies revealed hepatic nodules consisting of transient, sterile granulomas for which no cause could be determined. Stellate architecture histologically supported clinical evidence of subacute bacterial infection. Imaging modalities included: 99Tc-sulfur colloid (n = 2) and 67Ga (n = 2) scintigraphy; ultrasound (n = 5); computed tomography (n = 4); and magnetic resonance imaging (n = 2). Peripheral low density, as revealed by computed tomography in one and hyperintense halos on magnetic resonance imaging of another patient are both considered predictive for neoplastic disease but were associated with granulomas. The differential diagnosis of macroscopic liver lesions seen on imaging studies in febrile children should include the possibility of transient, idiopathic granulomas.

Prevalence of lumbosacral intervertebral disk abnormalities on MR images in pregnant and asymptomatic nonpregnant women

The prevalence of lumbosacral intervertebral disk bulge and herniation on sagittal magnetic resonance (MR) images was determined in 45 pregnant subjects and 41 asymptomatic nonpregnant women of childbearing age. MR technique differed for the pregnant and nonpregnant groups. Fifty-three percent of pregnant and 54% of nonpregnant women had an abnormal disk (bulge or herniation) at one or more levels (L3-4, L4-5, or L5-S1). The difference was not statistically significant. There was also no significant difference in the distribution of outcomes among the 45 pregnant subjects, 17 parous nonpregnant women, and 24 nulliparous women. The results suggest that lumbosacral disk bulges or herniations are common in women of childbearing age, whether pregnant or not, and that, contrary to an earlier report, pregnant women do not have an increased prevalence of disk abnormalities.

Characterization and identification of substances isolated from dialyzer extracts

The organic phase of dialyzer dried extracts obtained from Cuprophan hollow fiber and polyacrylonitrile AN 69 parallel-plate dialyzers, all sterilized by ethylene oxide, were submitted to light and polarized light microscopy, infrared (IR) spectrophotometry, and gas chromatography coupled with mass spectrometry. Colorless polygonal (approximately 5 X 20 micron) and needle-like (approximately 3 X 50 micron) crystals were found in great quantity on microscopy examination. IR spectrophotometry of the crystals embedded in potassium bromide disc showed specific spectra in the 1400-800 cm-1 wave number range and typical peaks on wave number assigned for hydroxy or amine (3420 cm-1), aromatic hydrogen (3060 cm-1), methyl, methylenic, or methenyl (2960-2860 cm-1), and carbonyl (1715 cm-1) groups can be demonstrated. Seven peaks were detected on gas chromatography of the organic solution containing crystals. Fatty acids and undefined compounds could originate from the dialyzer. Phtalates may leach from blood tubing, used in the rinsing procedure, and BHT is a stabilizer of ethyl ether used as solvent. These compounds could also originate from the dialyzer since phtalates are widely used as a plasticizer and BHT an antioxidant for various polymers.

Teardrop bladder: demonstration by magnetic resonance imaging

Teardrop deformity of the urinary bladder and ureteral deviation may be caused by iliopsoas hypertrophy. Magnetic resonance imaging (MRI) findings in such a case are described, and the potential advantages of MRI in evaluating the pelvis are discussed.

Venous thrombosis: clinical and experimental MR imaging

Five venous thrombi were induced in the external jugular veins of three laboratory dogs, and were repeatedly imaged over 3 weeks using a 0.35-T magnetic resonance (MR) imager. MR magnitude and phase images, T1 and T2 relaxation times, venography, and histologic sections of these thrombi were evaluated to determine the changes in appearance on MR images with time. Venous thrombi appeared hyperintense compared with muscle on both relatively T1- and T2-weighted spin-echo sequences regardless of the age of the clot. Organization of the thrombus beyond 1 week was manifested as increased prominence of flow signal void in and around the clot. Distinction between intraluminal thrombus and flow-related artifacts was aided by phase image reconstruction. Nineteen venous thrombi locations in 13 patients revealed an MR appearance similar to that of the experimental animal model. Three patients (six thrombi locations) had serial examinations over 4 weeks. No significant change in thrombus signal characteristics was noted with time. It is concluded that MR imaging at 0.35 T cannot be used to predict the age of thrombus (up to 3 weeks) but may be helpful in following its resolution.

Imaging the pediatric liver: MRI and CT

The livers of 27 children, 2 weeks to 16 years old, were examined with MRI and CT. Fourteen children had normal livers, 9 had focal liver disease, and 4 had diffuse liver disease. Normal intrahepatic venous anatomy was visualized more frequently with MRI than with CT, regardless of presence of disease, type of disease, or age. Focal hepatic lesions were either iso- or hypointense on relatively T1-weighted images and were hyperintense on T2-weighted images regardless of the pathology. In three cases, lesions seen with MRI were not detected with CT. In two other cases, CT was interpreted as equivocal or abnormal, but the liver was normal on MRI. MRI was superior to CT for evaluation of patency of the intrahepatic portion of the inferior vena cava. Other than in cases of fatty infiltration, CT provided no information additional to MRI. MRI has the potential to replace CT as a technique for imaging the pediatric liver in many cases, especially for infants and young children.

Pattern of urinary symptoms in patients with metastatic bladder cancer

In an attempt to assess the development or progression of symptoms in patients with metastatic bladder cancer we reviewed 41 patients who died of the disease but who did not undergo cystectomy. Therapy for the local tumor was used when indicated. Of the 41 patients 9 experienced worsening of symptoms, while the others were either stable or improved. Only 1 of 10 asymptomatic patients suffered symptoms during the course of the illness.

Pelvic masses in pregnant patients: MR and US imaging

Sixteen pregnant patients with pelvic masses detected with ultrasound (US) were studied with magnetic resonance (MR) imaging at 0.35 T. Two patients were in their first trimester, eight in the second, and six in the last. On MR images, 34 masses were seen, including 19 uterine leiomyomas. With US, 20 masses were detected. All masses not seen with US were leiomyomas. Only 20 masses (in 11 patients) were removed for histologic study. In nine cases, MR imaging and US provided similar information on the origin, extent, and type of mass. In seven patients, MR imaging contributed additional information. MR imaging depicted more leiomyomas than US in three patients. In another case, MR images showed that a mass depicted with US was actually a loop of bowel. MR images allowed differentiation between a solid soft-tissue mass and a hemorrhagic fluid-containing mass, correctly depicted the presence of an abdominal pregnancy, and allowed evaluation of the parametrium for spread of cervical carcinoma.

Preoperative and postoperative evaluation of the patient with a splenorenal shunt with magnetic resonance imaging

Preoperative and postoperative evaluation of the patient with a splenorenal shunt usually requires angiography. Magnetic resonance imaging is a safe technique that can provide information concerning vascular anatomy and shunt patency without the potential hazards of catheterization and iodinated contrast medium.

MRI evaluation of mediastinal and thoracic inlet venous obstruction

Fourteen patients with clinical and/or radiographic evidence of mediastinal or thoracic inlet venous obstruction were studied with magnetic resonance imaging (MRI) on a 0.35-T superconducting system using multislice spin-echo technique. The MRI examinations were retrospectively evaluated for their ability to provide information about the presence, level, and cause of venous obstruction, local extent of disease causing obstruction, and presence of collateral venous pathways. The results were compared to the information available from correlative studies including CT (11) and venography (four). In each instance, MRI provided detailed information about the precise site and extent of venous obstruction. The specific cause of the obstruction was suggested by MRI findings in one case of teratoma and in one case of postradiation fibrosis. Otherwise, all masses had relatively prolonged T1 T1 and T2 relaxation times and could not be differentiated on the basis of their and T2 relaxation times and could not be differentiated on the basis of their MRI appearances. Transaxial images most clearly and unequivocally depicted patent and obstructed superior vena cava (SVC). Enlarged venous collateral pathways were apparent in four cases. CT scans with intravenous contrast material in general provided information similar to that available with MRI, except in two cases where there was a discrepancy between CT and MRI concerning complete versus partial occlusion of the SVC. This initial study indicates that MRI can provide information about the presence, cause, and precise level of mediastinal and thoracic inlet venous obstruction.

Postoperative assessment of splenorenal shunts with MRI: preliminary investigation

Magnetic resonance imaging (MRI) was performed on nine patients with hepatic cirrhosis and portal hypertension after selective distal splenorenal shunt for decompression of bleeding esophageal varices. MRI demonstrated the splenorenal anastomosis and patency of the shunt, splenic vein, and left renal vein in each case. Imaging in the transverse plane provided optimal visualization of the shunts. The authors conclude that MRI is a safe, noninvasive technique for the postoperative evaluation of selective distal splenorenal shunts.

Assessment of pericardial constraint: the relation between right ventricular filling pressure and pericardial pressure measured after pericardiocentesis

Experimental studies have shown that right ventricular filling pressure (that is, intracavitary diastolic pressure) approximates pericardial surface pressure but, in many patients after removal of pericardial effusion, right ventricular filling pressure has been found to markedly exceed pericardial pressure recorded by an open catheter. The aim of this study was to determine whether this apparent contradiction was related to the technique of pericardial pressure measurement. Nine patients with chronic pericardial effusion were studied and, although these pressures diverged to varying degrees in individual patients, the previous observation was confirmed in that, although initially similar, right ventricular filling pressure and pericardial pressure (measured by means of an open catheter) tended to diverge during removal of the effusate; when the evacuation was as complete as possible pericardial pressure was 2.1 +/- 1.0 (mean +/- SE), while right ventricular filling pressure was 8.7 +/- 1.7 mm Hg (p less than 0.01). In six open chest, anesthetized, volume-loaded dogs with pericardial effusion (50 ml), right ventricular filling pressure and pericardial pressures measured with both open catheter and flat balloon were all equal. With decreasing volume of pericardial fluid, right ventricular filling pressure and pericardial pressure (by catheter) diverged as had been observed in patients. However, pericardial pressure (balloon) continued to be equal to right ventricular filling pressure. (With 0 ml in the pericardium, right ventricular filling pressure = 12.9 +/- 0.9 mm Hg, pericardial pressure [catheter] = 1.4 +/- 1.9 mm Hg and pericardial pressure [balloon] = 12.4 +/- 1.5 mm Hg.) Thus, these observations support the use of right ventricular filling pressure as an estimate of pericardial constraint in patients.

Arteriovenous malformations of the extremities: MR imaging

Eight patients with angiographically proved arteriovenous malformations (AVMs) of the extremities (seven congenital, one posttraumatic) were evaluated with magnetic resonance (MR) imaging using a 0.35-T superconducting system and spin-echo pulse sequences. Congenital AVMs appeared as accumulations of dilated tortuous blood vessels infiltrating the involved muscles. A posttraumatic acquired AVM of the shoulder consisted of a large feeding artery associated with a pseudoaneurysm and a soft-tissue mass. MR imaging allowed precise anatomic localization and provided details concerning the size and extent of the AVMs. The relationship of AVMs to specific muscle groups, bones, and vascular structures could be accurately determined. Although major feeding and draining vessels were identified, the exact arteries and veins supplying and draining the AVM could not be ascertained. Images obtained in the transverse plane consistently yielded the most useful information. MR imaging and angiography may be complementary techniques in the initial evaluation, follow-up, and treatment planning of AVMs of the extremities.

Human fetal anatomy: MR imaging

Twenty-four pregnant women carrying 26 fetuses (two sets of twins) were imaged with magnetic resonance (MR) imaging at 0.35 T following sonographic evaluation. Each study was retrospectively evaluated to determine which of 33 normal fetal structures were visible on the images and which imaging parameters were most useful for depicting fetal anatomy. Fetal motion degraded fetal images in all but two cases, both with oligohydramnios and in the third trimester of gestation. Nevertheless, many fetal structures were identifiable, particularly in the third trimester. Visualization of fetal anatomy improved with intravenous maternal sedation in five cases. Relatively T1-weighted images occasionally offered the advantage of less image degradation owing to fetal motion and improved contrast between different fetal structures. More T2 weighting was believed to be advantageous in one case for outlining the fetal head and in one case for delineation of the brain. In many cases, structures were similarly identifiable (though with different signal intensities) regardless of the parameters selected. The authors conclude that MR imaging of many fetal structures is currently unsatisfactory and is probably of limited value, particularly in the first and second trimesters. However, the relative frequency and detail with which the fetal head and liver can be depicted indicate that these may be areas for further investigation, and the potential utility of imaging fetal fat warrants further investigation.

MR imaging of iliopsoas bursitis and concurrent avascular necrosis of the femoral head

The magnetic resonance (MR) features of iliopsoas bursitis secondary to an inflammatory arthropathy of the hip are described in a patient with concurrent avascular necrosis of the femoral heads. The MR findings of avascular necrosis were demonstrated on one side where radiography, bone scan, and CT were negative.

Iliopsoas muscles: MR study of normal anatomy and disease

Magnetic resonance (MR) imaging was performed on 15 healthy subjects to define the appearance of the iliopsoas muscle and on 15 patients with iliopsoas disease. Seven patients had tumorous involvement of the muscles, five had inflammatory disease, one had retroperitoneal hemorrhage, one had iliopsoas bursitis, and one had bilateral hypertrophy. MR imaging permitted delineation of the muscles and depiction of the disease condition. Transverse MR images alone almost always provided the necessary data to determine the origin and extent of disease. Sagittal images were occasionally useful in defining the extension of disease into the spine. T1-weighted images provided optimal contrast between the muscles and adjacent tissues, while T2-weighted images were more useful for depicting disease within the muscles themselves.

Chemical shift artifact in clinical magnetic resonance images at 0.35 T

A thin, low-intensity line, which partially surrounds many structures on magnetic resonance imaging (MRI), is an artifact due to the phenomenon of chemical shift and should not be mistaken for a normal or abnormal morphologic structure. This artifact can be recognized by its characteristic appearance perpendicular to the direction of the frequency-encoding gradient at the interface of tissues with different chemical shift properties. Confinement within or extension beyond this thin, low-intensity line cannot be used as a criterion for staging neoplasms. Once recognized, the chemical shift artifact should not impede the use of MRI for clinical imaging at 0.35 T.

Fluid collections in the intraperitoneal and extraperitoneal spaces: comparison of MR and CT

Fourteen patients with abnormal subdiaphragmatic fluid collections (eight intraperitoneal, two extraperitoneal, and four intra- and extraperitoneal) were examined with computed tomography (CT) and magnetic resonance (MR) imaging. MR and CT provided equivalent information concerning the presence and extent of fluid collections in 13 of the 14 cases. Image acquisitions with two different repetition times (TRs) and two echo times (TEs) were necessary, in most cases, to detect and discriminate between different types of pathologic fluids. Transudative ascites demonstrated long T1 and T2 relaxation times, whereas abscesses, phlegmon, pancreatic pseudocyst, exudative pancreatitis, and chronic hematoma demonstrated an intermediate or short T1 and a long T2.

Doxorubicin plus cisplatin in the treatment of apudomas

Twelve patients with advanced apudomas--six with carcinoid tumors, two with chemodectomas, two with pancreatic islet cell tumor, and one each of medullary carcinoma of the thyroid and paraganglioma of unknown primary--were treated with a combination of doxorubicin 50 mg/m2 and cisplatin 50 mg/m2 every 3 to 4 weeks. Biochemical markers were present in 8 of the 12 patients. Five of the 12 patients (3 with carcinoid and 2 with chemodectomas) responded with more than 50% regression of tumor size measured as hypothetical area. Three others (two with islet cell tumors and one with carcinoid) had clinical and/or biochemical improvements. A median duration of response was 6 months. Nausea, vomiting, and alopecia were universal. Mild or moderate leukopenia was the most frequent toxicity. No sustained nephrotoxicity was seen. The combination of doxorubicin and cisplatin provides a new palliative therapy for patients with APUD tumors.

Prevalence of mitral valve prolapse in normal children

Although echocardiography has become the standard noninvasive method of diagnosing mitral valve prolapse, the diagnostic criteria have been established without clearly defining the range of normal patterns for mitral valve closure. The current study reports the analysis of mitral valve closure patterns in 193 children (aged 5 days to 18 years) making scheduled visits for well child care who were screened by history and physical examination to exclude structural heart disease. Mitral valve systolic leaflet position was analyzed for the appearance of any portion of either leaflet superior to the plane of the anulus. Superior systolic motion was noted in 13% of the overall study group; this pattern was uncommon in infants but more frequent in older children, with a prevalence of 35% in the 10 to 18 year age group. There was no statistically significant difference between male and female children at any age. The prevalence of superior systolic motion decreased markedly if consideration was given to its presence in more than one echocardiographic view (1%) or to displacement of the coaptation point of the mitral valve leaflets (0.5%). Superior systolic motion occurs with such frequency in normal children as to call into question the reliability of this pattern of mitral valve closure as a standard for the diagnosis of mitral valve prolapse. More restrictive diagnostic criteria which consider the degree of leaflet displacement or its presence in multiple echocardiographic views may be necessary to identify those subjects whose mitral valve closure patterns truly fall outside the range of normal.

Role of carotid artery resistance to collapse during high-intrathoracic-pressure CPR

The driving force for carotid artery flow during high-intrathoracic-pressure cardiopulmonary resuscitation is a peripheral arteriovenous pressure gradient resulting from differential transmission of the high intrathoracic pressure to the carotid artery but not to the jugular vein. To study the role of carotid artery resistance to collapse in establishing this differential pressure transmission, we manipulated the upstream, downstream, and surrounding pressures and measured the resultant carotid artery flow in both intact dogs and in excised arteries. Stepwise reductions in downstream pressure produced a narrowing near the outlet from the high-pressure chamber (the thorax in vivo), but increments in flow continued despite the presence of a positive (outside--inside) transmural pressure gradient. Flow limitation occurred only when downstream pressure was further decreased. Resistance to collapse was indexed by the transmural pressure at the onset of flow limitation (Pcrit), which was 7.2 +/- 1.6 mmHg in eight intact dogs. After administration of norepinephrine Pcrit increased by 2.6 +/- 0.7 mmHg, P less than 0.001). Seven excised carotid arteries also demonstrated resistance to collapse which was enhanced somewhat with norepinephrine. Thus resistance of the carotid artery to collapse is a critical factor in maintaining forward flow during high intrathoracic pressure. This resistance to collapse is also seen in vitro and can be enhanced by vasoconstricting agents.

Interstitial pneumonitis complicating rheumatoid arthritis. Sustained remission with azathioprine therapy

A patient with classic rheumatoid arthritis developed biopsy-proven diffuse interstitial pulmonary fibrosis and ventilatory insufficiency which appeared to be irreversible. The administration of azathioprine coincided with significant immediate improvement in pulmonary function and clinical status. During five years of continuous azathioprine therapy, progressive improvement in lung function has been accompanied by marked deterioration of the rheumatoid joint disease, suggesting that the pulmonary and joint lesions of rheumatoid disease may not be mediated by the same pathways.

Chemotherapy for bronchogenic carcinoma. Methotrexate, doxorubicin, cyclophosphamide, and lomustine

A combination chemotherapy (MACC) consisting of methotrexate, doxorubicin hydrochloride (Adriamycin), cyclophosphamide, and lomustine (CCNU) was given to 41 patients with stage III bronchogenic carcinoma, 34 of whom had disseminated disease. The objective response rate was 46% for all patients with a median actuarial survival of nine months. Response was seen in all cell types, including four of ten patients with squamous cell carcinoma, six of 17 with adenocarcinoma, and six of seven with small-cell anaplastic carcinoma. Prolongation of survival was apparent for patients of all cell types. Toxic reactions were moderate and allowed for easy outpatient use.

Prevention of bony fluorosis in aluminum smelter workers. A five-year study of fluoride absorption and excretion -- Pt. 3

1. A study of over 52,000 urinary fluoride determinations collected over a 5-year period among aluminum smelter workers is described. The pre-shift urinary fluoride concentration (representative of bony burden) appears to increase less rapidly than the post-shift concentration. This slow rate of bony buildup of pre-shift urinary fluoride concentrations reflects the relatively slow uptake of fluoride by osseous tissues at these levels of exposure. 2. The utility of post-shift urinary fluoride analysis is reflected by its close correlation with improvement or deterioration in work practices which determines the degree of potential fluoride exposure. 3. Over 16,000 urinary tests for protein were performed in aluminum smelter workers. The absence of correlation between urinary fluoride concentrations and the presence of albuminuria indicates the absence of renal alteration among these workers.

Prevention of bony fluorosis in aluminum smelter workers. Excretion of fluorides during a seven-day workweek -- Pt. 2

1. The excretion of fluoride is examined among aluminum smelter workers over the course of a seven-day workweek. The data for the first three days of work is best described by the first cycle of a parabolic curve. Each curve is characteristic of the level of exposure associated with specific jobs and individual smelter hygienic conditions. 2. The variability associated with the post-shift values after apparent equilibrium is attained is extreme. Such variability is probably due in large part to differences in exposure occurring during the last few hours of that work-day. This is further augmented as essentially all the absorbed fluoride is excreted as the near-equilibrium state is attained. 3. Because of this variability, the use of the post-shift urinary fluoride concentration as an indicator of exposure conditions should be limited to groups of workers, rather than individuals, at possible risk. 4. It appears that a urinary fluoride sample taken any day after the third day of the shift is an adequate post-shift fluoride exposure indicator among these groups of workers.