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1.
J Appl Physiol (1985) ; 91(2): 645-53, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11457776

ABSTRACT

Cardiac muscle adapts well to changes in loading conditions. For example, left ventricular (LV) hypertrophy may be induced physiologically (via exercise training) or pathologically (via hypertension or valvular heart disease). If hypertension is treated, LV hypertrophy regresses, suggesting a sensitivity to LV work. However, whether physical inactivity in nonathletic populations causes adaptive changes in LV mass or even frank atrophy is not clear. We exposed previously sedentary men to 6 (n = 5) and 12 (n = 3) wk of horizontal bed rest. LV and right ventricular (RV) mass and end-diastolic volume were measured using cine magnetic resonance imaging (MRI) at 2, 6, and 12 wk of bed rest; five healthy men were also studied before and after at least 6 wk of routine daily activities as controls. In addition, four astronauts were exposed to the complete elimination of hydrostatic gradients during a spaceflight of 10 days. During bed rest, LV mass decreased by 8.0 +/- 2.2% (P = 0.005) after 6 wk with an additional atrophy of 7.6 +/- 2.3% in the subjects who remained in bed for 12 wk; there was no change in LV mass for the control subjects (153.0 +/- 12.2 vs. 153.4 +/- 12.1 g, P = 0.81). Mean wall thickness decreased (4 +/- 2.5%, P = 0.01) after 6 wk of bed rest associated with the decrease in LV mass, suggesting a physiological remodeling with respect to altered load. LV end-diastolic volume decreased by 14 +/- 1.7% (P = 0.002) after 2 wk of bed rest and changed minimally thereafter. After 6 wk of bed rest, RV free wall mass decreased by 10 +/- 2.7% (P = 0.06) and RV end-diastolic volume by 16 +/- 7.9% (P = 0.06). After spaceflight, LV mass decreased by 12 +/- 6.9% (P = 0.07). In conclusion, cardiac atrophy occurs during prolonged (6 wk) horizontal bed rest and may also occur after short-term spaceflight. We suggest that cardiac atrophy is due to a physiological adaptation to reduced myocardial load and work in real or simulated microgravity and demonstrates the plasticity of cardiac muscle under different loading conditions.


Subject(s)
Bed Rest , Heart/physiology , Hemodynamics , Myocardium/pathology , Space Flight , Weightlessness , Adult , Analysis of Variance , Atrophy , Blood Pressure , Cardiac Output , Heart Rate , Humans , Magnetic Resonance Imaging , Male , Stroke Volume , Time Factors , Vascular Resistance
2.
J Magn Reson Imaging ; 13(6): 868-75, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11382946

ABSTRACT

Twenty consecutive patients with breast cancer were evaluated following chemotherapy using MRI to assess the size of cancer residua and compare these data with subsequent histologic measurements of the viable tumor. This retrospective study also involved assessment of the preoperative size of the malignancy as determined by physical exam and x-ray mammogram. These values were later compared with the histology. The tumor size correlation coefficient between MRI and pathologic analysis was the highest, at 0.93. Physical exam and x-ray mammography (available for 17 patients) produced correlation coefficients of 0.72 and 0.63, respectively, compared to histologic measurement. The accuracy of MRI did not vary with the size of cancer residua. MRI is an accurate method for preoperative assessment of breast cancer residua following chemotherapy. J. Magn. Reson. Imaging 2001;13:868-875.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Breast , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Mammography , Neoplasm, Residual/diagnosis , Palpation , Adult , Aged , Biopsy, Needle , Breast/pathology , Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/diagnosis , Carcinoma, Ductal, Breast/drug therapy , Carcinoma, Ductal, Breast/pathology , Carcinoma, Lobular/diagnosis , Carcinoma, Lobular/drug therapy , Carcinoma, Lobular/pathology , Female , Humans , Middle Aged , Neoplasm, Residual/pathology , Sensitivity and Specificity , Treatment Outcome , Ultrasonography, Mammary
3.
J Clin Endocrinol Metab ; 86(1): 59-65, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11231979

ABSTRACT

The lamin A/C (LMNA) gene has recently been reported to be mutated in familial partial lipodystrophy, Dunnigan variety (FPLD). We found mutations within exon 8 of LMNA (R482Q, R482W, and G465D) in 12 families with typical FPLD and in exon 11 (R582H) in 1 atypical family. To investigate phenotypic heterogeneity, we compared body fat distribution, using anthropometry and whole body magnetic resonance imaging, and metabolic parameters in women with atypical and typical FPLD. Compared with women with typical FPLD, the two sisters with atypical FPLD had less severe loss of sc fat from all the extremities and trunk and particularly from the gluteal region and medial parts of proximal thighs. Both types had similar excess of fat deposition in the neck, face, intraabdominal, and intermuscular regions. Women with atypical FPLD tended to have lower serum triglyceride and higher high density lipoprotein cholesterol concentrations. As exon 11 of LMNA does not comprise part of the lamin C-coding region, the R582H mutation affects only lamin A protein. Therefore, a unique phenotype of atypical FPLD may result from disrupted interaction of lamin A with other proteins and chromatin compared with typical FPLD, in which interaction of both lamins A and C may be disrupted.


Subject(s)
Genetic Variation , Lipodystrophy/genetics , Mutation, Missense , Nuclear Proteins/genetics , Adipose Tissue/pathology , Adult , Anthropometry , Body Composition , Female , Humans , Lamin Type A , Lamins , Lipodystrophy/diagnosis , Lipodystrophy/pathology , Lipodystrophy/physiopathology , Magnetic Resonance Imaging , Male , Middle Aged , Phenotype
4.
Semin Musculoskelet Radiol ; 4(4): 435-58, 2000.
Article in English | MEDLINE | ID: mdl-11371328

ABSTRACT

Tumors that involve skeletal muscle are numerous and varied, including a variety of benign and malignant neoplasms as well as other mass lesions. Confronted with a patient presenting with a mass in the muscle, a clinician has multiple choices for the initial study. Magnetic resonance imaging (MRI) frequently provides all of the information necessary to manage patients and so is a reasonable "first-line" imaging test. Although the MRI features of the various muscle masses are variable, general rules regarding characteristic features can provide restricted differential diagnosis. This article reviews these tumors and their appearances on MRI.


Subject(s)
Magnetic Resonance Imaging/methods , Muscle Neoplasms/diagnosis , Contrast Media , Diagnosis, Differential , Humans , Muscle, Skeletal/pathology
5.
Clin Orthop Relat Res ; (350): 85-9, 1998 May.
Article in English | MEDLINE | ID: mdl-9602805

ABSTRACT

A prospective study of adolescents with femoral fractures treated with intramedullary nailing was done to identify complications and evaluate the outcome of this method of treatment. Sixty patients with femoral fractures have been treated with antegrade intramedullary nailing. Magnetic resonance imaging scans were obtained to evaluate for subclinical avascular necrosis of the femoral head. The average patient age was 12 years. All patients had open physes at the time of surgery. Implants were removed in 33 patients to date at an average of 10 months after initial nailing. All but two patients continue to have no signs of avascular necrosis, no rotational or angular deformity, and no nerve palsy. Two patients have had subclinical avascular necrosis as seen on magnetic resonance imaging. One patient had avascular necrosis develop in both femoral heads 1 year after nail removal from the right femur. The second patient has asymptomatic marrow changes on magnetic resonance imaging consistent with avascular necrosis with no femoral head collapse. It is thought that intramedullary nailing of pediatric femoral fractures is a safe treatment option. Few complications and a small risk of subclinical presentation of avascular necrosis of the femoral head that can become evident after removal of the implant have been found.


Subject(s)
Femoral Fractures/surgery , Fracture Fixation, Intramedullary , Adolescent , Bone Nails , Child , Femur Head Necrosis/etiology , Humans , Postoperative Complications , Prospective Studies , Treatment Outcome
6.
Orthop Clin North Am ; 29(1): 1-17, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9405775

ABSTRACT

Cost-effective imaging evaluation of a suspected soft tissue tumor requires knowledge of all available imaging modalities, including indications for each and relative advantages and disadvantages. Imaging studies are useful in pre-treatment diagnostic evaluation, biopsy planning, and post-treatment evaluation for recurrence. Close communication between the orthopedic surgeon and radiologist is essential for appropriate management. This article will emphasize an approach to the imaging evaluation of a suspected soft tissue tumor.


Subject(s)
Soft Tissue Neoplasms/diagnosis , Algorithms , Diagnosis, Differential , Humans , Magnetic Resonance Imaging , Neoplasm Staging , Soft Tissue Neoplasms/surgery
7.
J Cereb Blood Flow Metab ; 17(4): 363-9, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9143218

ABSTRACT

Elucidation of the role of cerebral hyperthermia as a secondary factor that worsens outcome after brain injury, and the therapeutic application of modest brain hypothermia would benefit from noninvasive measurements of absolute brain temperature. The present study was performed to evaluate the feasibility of using 1H magnetic resonance (MR) spectroscopy to measure absolute brain temperature in human subjects on a clinical imaging spectroscopy system operating at a field strength of 1.5 T. In vivo calibration results were obtained from swine brain during whole-body heating and cooling, with concurrent measurements of brain temperature via implanted probes. Plots of the frequency differences between the in vivo MR peaks of water and N-acetyl-aspartate and related compounds (NAX), or water and choline and other trimethylamines versus brain temperature were linear over the temperature range studied (28-40 degrees C). These relationships were used to estimate brain temperature from 1H MR spectra obtained from 10 adult human volunteers from 4 cm3-volumes selected from the frontal lobe and thalamus. Oral and forehead temperatures were monitored concurrently with MR data collection to verify normothermia in all the subjects studied. Temperatures determined using N-acetyl-aspartate or choline as the chemical shift reference did not differ significantly, and therefore results from these estimates were averaged. The brain temperature (mean +/- SD) measured from the frontal lobe (37.2 +/- 0.6 degrees C) and thalamus (37.7 +/- 0.6 degrees C) were significantly different from each other (paired t-test, p = 0.035). We conclude that 1H MR spectroscopy provides a viable noninvasive means of measuring regional brain temperatures in normal subjects and is a promising approach for measuring temperatures in brain-injured subjects.


Subject(s)
Body Temperature , Brain/physiology , Magnetic Resonance Spectroscopy , Adult , Animals , Animals, Newborn , Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Brain/metabolism , Choline/metabolism , Humans , Methylamines/metabolism , Protons , Reference Values , Swine
8.
Magn Reson Imaging Clin N Am ; 3(4): 669-94, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8564689

ABSTRACT

Not only is MR imaging maximally sensitive to the presence of musculoskeletal soft-tissue lesions, but also it provides exquisite definition of their features. Categorization of the many distinct attributes of the lesions is the key to differentiation of benign from malignant processes. Combining the observations concerning the architectural details with the location and pattern of growth, and finally with the specific MR signal characteristics and contrast enhancement patterns, will produce the most limited differential diagnosis possible. Although there are few, if any, pathognomonic findings for malignant or benign lesions in diagnostic imaging, a high degree of confidence or statistical likelihood can be achieved in many instances using MR imaging.


Subject(s)
Bone Neoplasms/diagnosis , Magnetic Resonance Imaging , Muscle Neoplasms/diagnosis , Soft Tissue Neoplasms/diagnosis , Bone Diseases/diagnosis , Bone Diseases/pathology , Bone Neoplasms/pathology , Contrast Media , Cysts/diagnosis , Cysts/pathology , Diagnosis, Differential , Humans , Image Enhancement/methods , Magnetic Resonance Imaging/methods , Muscle Neoplasms/pathology , Muscular Diseases/diagnosis , Muscular Diseases/pathology , Sensitivity and Specificity , Soft Tissue Neoplasms/pathology
9.
Magn Reson Imaging Clin N Am ; 3(4): 753-72, 1995 Nov.
Article in English | MEDLINE | ID: mdl-8564694

ABSTRACT

Over the past decade, MR imaging has become one of the most valuable imaging tools for evaluation of musculoskeletal pathology. This is due to its high sensitivity to the vast majority of acute and chronic musculoskeletal injuries and the starting anatomic clarity provided. The latter feature allows definition of characteristic injury patterns, which is the key to most diagnoses and also usually allows accurate grading of the severity of injuries. Careful attention to imaging technique and the specific architectural patterns of musculotendinous disruption by the imaging specialist will result in accurate diagnoses for the patient and referring physician.


Subject(s)
Magnetic Resonance Imaging , Muscle, Skeletal/injuries , Soft Tissue Injuries/diagnosis , Tendon Injuries/diagnosis , Bone and Bones/injuries , Humans , Image Enhancement/methods , Magnetic Resonance Imaging/methods , Sensitivity and Specificity
11.
Plast Reconstr Surg ; 96(4): 865-77, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7652061

ABSTRACT

Rupture of a breast implant is a recognized complication of augmentation mammaplasty and reconstructive breast surgery. Due to concerns over the extravasation of silicone gel within adjacent tissue and distant body sites, considerable attention has been given to the radiographic detection of mammary implant rupture. A metaanalysis comparing the accuracy of various currently available imaging modalities was conducted and an algorithm suggested to guide clinicians in the detection of breast implant rupture. Advantages and limitations of mammography, xeromammography, ultrasonography, MRI, and CT are outlined as well as some of the most specific radiographic signs of each with illustrative examples from patients evaluated at our institution. Results of our retrospective analysis corroborated by a review of the most recent literature reveal that mammography supplemented with ultrasonography constitutes the most cost-effective initial study, followed by MRI if these are equivocal. MRI is the most sensitive and specific study to evaluate breast implant rupture.


Subject(s)
Breast Implants/adverse effects , Breast/pathology , Mammography , Female , Humans , Magnetic Resonance Imaging , Prosthesis Failure , Sensitivity and Specificity , Tomography, X-Ray Computed , Ultrasonography, Mammary , Xeroradiography
13.
Radiology ; 190(2): 467-74, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8284401

ABSTRACT

PURPOSE: To define the characteristics of chondroblastoma at magnetic resonance (MR) imaging and the combination of findings that are diagnostic for chondroblastoma. MATERIALS AND METHODS: From January 1987 through December 1992, 22 patients with histologically confirmed chondroblastoma and prior MR imaging examinations were seen. Patients included 16 men and six women, aged 10-58 years (median, 17 years). Retrospective analysis of findings at MR imaging, plain radiography, computed tomography, and bone scanning was performed. RESULTS: Low to intermediate heterogeneous signal intensity, lobular internal architecture, and fine lobular margins were well defined with high-resolution T2-weighted (repetition time > or = 1,500 msec, echo time > or = 70 msec) MR imaging. Adjacent bone-marrow and soft-tissue edema and periosteal reactions were more dramatically demonstrated on MR images than on radiographs. Bone marrow edema was prominent in all but five cases. Obvious periosteal reaction and adjacent soft-tissue edema were visible in 17 cases. CONCLUSION: Knowledge of the MR imaging findings of chondroblastoma will allow accurate diagnosis and help avoid confusion with infection and aggressive neoplasms.


Subject(s)
Bone Neoplasms/diagnosis , Chondroblastoma/diagnosis , Magnetic Resonance Imaging , Adolescent , Adult , Bone Neoplasms/diagnostic imaging , Child , Chondroblastoma/diagnostic imaging , Female , Humans , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed
14.
J Clin Endocrinol Metab ; 76(5): 1217-23, 1993 May.
Article in English | MEDLINE | ID: mdl-8496313

ABSTRACT

The purpose of this study was to prospectively compare the effectiveness of administering medroxyprogesterone acetate (MPA; 20 mg/day) in either the first (protocol A) or last (protocol B) 12-week period along with a 6-month course of the GnRH analog (GnRH-a; leuprolide acetate; 1 mg/day, sc) on uterine and leiomyomata volumes and hormone (estradiol, LH, and FSH) and serum lipid (total cholesterol, triglycerides, and high and low density lipoprotein) levels. Sixteen women were randomized into protocol A or B, received either MPA or placebo along with GnRH-a, respectively, and were then crossed over at 12 weeks to placebo or MPA, respectively, for the final 12-week interval of GnRH-a therapy. Total, myoma, and nonmyoma uterine volumes were determined by magnetic resonance imaging, and serum studies were performed at the beginning of the study and at 12 and 24 weeks. In both protocols, LH and estradiol levels declined by 80-90% (P < 0.03) and 55-72% (P < 0.02) of the baseline, respectively, at 12 weeks and remained at this level at 24 weeks. There were no significant changes in the other laboratory tests between protocols or longitudinally over time. Total uterine volume decreased to 73% of the baseline at 12 weeks in protocol B (P < 0.04), but did not change in protocol A. After crossover at 12 weeks, the total uterine volume of women in protocol A decreased to 74% of the baseline (P < 0.02) at 24 weeks. Between-protocol comparisons demonstrated a greater decline in total uterine volume in protocol B than A at 12 weeks, but after cross-over, MPA addition was associated with a significant increase in total uterine volume (protocol B) compared to a decrease in protocol A at 24 weeks (P < 0.005). In contrast, although myoma volume declined in both protocols, no significant changes in myoma volume were detected within or between groups over the treatment period. Nonmyoma volume changes in protocols A and B roughly paralleled total uterine volume changes, with MPA coadministration showing a correlation with a reversal in the GnRH-a-associated decrease in nonmyomatous tissue volume.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Gonadotropin-Releasing Hormone/analogs & derivatives , Leiomyoma/drug therapy , Magnetic Resonance Imaging , Medroxyprogesterone Acetate/therapeutic use , Triptorelin Pamoate/analogs & derivatives , Uterine Neoplasms/drug therapy , Adult , Double-Blind Method , Estradiol/blood , Female , Follicle Stimulating Hormone/blood , Gonadotropin-Releasing Hormone/therapeutic use , Humans , Leiomyoma/blood , Leiomyoma/diagnosis , Luteinizing Hormone/blood , Middle Aged , Placebos , Prospective Studies , Uterine Neoplasms/blood , Uterine Neoplasms/diagnosis
15.
Radiology ; 180(2): 533-9, 1991 Aug.
Article in English | MEDLINE | ID: mdl-2068324

ABSTRACT

Prospective and retrospective magnetic resonance (MR) imaging (0.35-T) interpretations were compared with final diagnoses in 110 patients suspected to have osteomyelitis. Diagnostic criteria of dark marrow on T1-weighted images and bright marrow on short-tau inversion-recovery images yielded a prospective sensitivity of 98% and a prospective specificity of 75%. Sixty percent of uncomplicated septic joint effusions demonstrated abnormal marrow signal intensity that was mistaken for osteomyelitis. Retrospective review revealed that overall specificity could be improved to 82% without loss of sensitivity if increased marrow signal intensity on T2-weighted images were included as an additional criterion. Specificity may be further increased by use of knowledge of morphologic patterns that distinguish various forms of osteomyelitis. Ten patients (9%) had potential pitfall diagnoses (eg, fracture, infarction, healed infection) that mimic osteomyelitis. MR imaging can be sensitive and specific for osteomyelitis if characteristic appearances and pitfall diagnoses are incorporated into the diagnostic criteria.


Subject(s)
Magnetic Resonance Imaging , Osteomyelitis/diagnosis , Acute Disease , Adolescent , Adult , Aged , Arthritis, Infectious/complications , Bone Marrow/pathology , Child , Child, Preschool , Chronic Disease , Diabetes Complications , Female , Humans , Infant , Magnetic Resonance Imaging/methods , Male , Middle Aged , Muscular Diseases/complications , Osteomyelitis/pathology , Prospective Studies , Retrospective Studies , Sensitivity and Specificity
16.
Magn Reson Q ; 7(2): 79-103, 1991 Apr.
Article in English | MEDLINE | ID: mdl-1911234

ABSTRACT

Clinical evaluation of the locomotor system has long been hampered by difficulty in assessing the morphologic and functional integrity of skeletal muscles. Diagnostic imaging represents a major advance in the diagnosis and management of patients with locomotor dysfunction through the possibility of probing beyond overlying soft tissues to identify muscle lesions, determine their extent, characterize their composition, direct invasive procedures, and monitor therapies. Magnetic resonance imaging (MRI) appears to be the most promising of available imaging methods, because of its great sensitivity to changes in muscle water distribution and fat content. Also, it can distinguish between individual deep and superficial muscles. Serial evaluations of many muscles are practical because of the safety of MRI. While the cost effectiveness in the workup of locomotor dysfunction remains to be determined, the scientific and practical clinical information now available merits further investigation by clinicians and radiologists alike. The purpose of this review is to describe the potential role of skeletal muscle MRI in evaluating the locomotor system.


Subject(s)
Leg/pathology , Locomotion , Magnetic Resonance Imaging , Muscles/pathology , Muscular Diseases/diagnosis , Neuromuscular Diseases/diagnosis , Humans , Leg/anatomy & histology , Leg/physiology , Leg/physiopathology , Muscles/anatomy & histology , Muscles/physiology , Muscles/physiopathology
17.
J Comput Assist Tomogr ; 14(6): 909-11, 1990.
Article in English | MEDLINE | ID: mdl-2229565

ABSTRACT

Spinal cord transection following breech or difficult cephalic deliveries has been well described. It is important to be aware that spinal cord transection in children may occur following severe trauma such as motor vehicle accidents often without evidence of underlying skeletal injury. We report three pediatric cases, one of which showed no evidence of underlying skeletal injury and two where the level of cord transection was below and remote from the site of a cervical fracture. When a neurologic deficit does not correlate with a known bony or ligamentous level of injury or is present despite normal routine plain radiographs, further imaging is warranted to exclude a remote cord transection as demonstrated in our patients.


Subject(s)
Magnetic Resonance Imaging , Spinal Cord Injuries/diagnosis , Accidents, Traffic , Child, Preschool , Female , Humans , Infant , Spinal Cord Injuries/etiology
18.
Radiology ; 172(3): 793-8, 1989 Sep.
Article in English | MEDLINE | ID: mdl-2772190

ABSTRACT

Sports-related muscle pain is frequent in both trained and untrained persons; however, its severity and significance may be difficult to assess clinically. The authors used magnetic resonance (MR) imaging to evaluate acute strains and delayed-onset muscle soreness in sedentary subjects and postmarathon myalgia in trained runners. MR imaging documented the distribution of affected muscles and the absence of focal hematoma, fascial herniation, subsequent fibrosis, and fatty infiltration. Pain associated with strain and that occurring several days after exercise were both associated with prolongation of muscle T1 and T2. In a prospective evaluation of delayed-onset muscle soreness, abnormalities depicted at MR imaging persisted longer than symptoms by up to 3 weeks, indicating that MR imaging is sensitive to tissue alteration that is not apparent clinically. Highly trained marathon runners tended to have relatively mild abnormalities involving the myotendinous junctions.


Subject(s)
Athletic Injuries/diagnosis , Magnetic Resonance Imaging , Muscles/injuries , Sprains and Strains/diagnosis , Female , Humans , Male , Muscles/pathology , Pain/etiology , Physical Exertion , Prospective Studies , Running , Time Factors
19.
Magn Reson Imaging ; 7(2): 187-94, 1989.
Article in English | MEDLINE | ID: mdl-2541298

ABSTRACT

Thirty-two (32) patients with primary hyperparathyroidism (17 with prior localization surgery, 15 without) were studied by a combination of computed tomography (CT), ultrasound (US), nuclear medicine (NM), and magnetic resonance imaging (MRI) for parathyroid adenoma localization. The sensitivity and true-positive ratio of each imaging technique and various combinations of techniques were evaluated. Of the 28 proven parathyroid adenomas (27 by surgery, 1 by digital subtraction angiography), 24 were imaged by two techniques, 19 by three techniques, and 10 by all four imaging techniques. The sensitivities were NM (65%), CT (76%), US (77%), and MRI (81%). The differences between true-positive ratios of 82%, 64%, 71%, and 77%, respectively, were not statistically significant. If multiple techniques were considered as a single test (i.e., a positive localization requires two or more tests to be positive at the same location), then sensitivity for a two-study combination was 79% and true-positive ratio 86%. Three techniques showed a sensitivity of 63% and a true-positive ratio of 92%, four modalities 40% and 100%, respectively. There was no significant difference in the various combinations of techniques employed (e.g., CT and US, US and MR, NM and MR, etc.). Thus, there appears to be an advantage in performing multiple techniques (regardless of which combination is selected) until two tests are positive at the same location.


Subject(s)
Adenoma/diagnosis , Parathyroid Neoplasms/diagnosis , Adenoma/diagnostic imaging , Adolescent , Adult , Aged , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasms, Multiple Primary/diagnosis , Neoplasms, Multiple Primary/diagnostic imaging , Parathyroid Neoplasms/diagnostic imaging , Radionuclide Imaging , Sodium Pertechnetate Tc 99m , Subtraction Technique , Thallium Radioisotopes , Tomography, X-Ray Computed , Ultrasonography
20.
AJNR Am J Neuroradiol ; 4(3): 344-6, 1983.
Article in English | MEDLINE | ID: mdl-6410740

ABSTRACT

Iohexol is a new, nonionic water-soluble contrast agent undergoing early clinical trials in the United States. Using a double-blind, parallel format, iohexol was compared with meglumine iothalamate (60 patients) for selective cerebral angiography, and with sodium meglumine diatrizoate (40 patients) for arch aortography. Iohexol produced significantly less pain than meglumine iothalamate or sodium meglumine diatrizoate. There were no significant differences in terms of heart rate, blood pressure, or electrocardiogram (ECG) changes. Both produced a transient tachycardia and hypotension after arch aortography, but significantly less so with iohexol. No significant complications occurred. Film quality was comparable between contrast agents except for diminished motion artifacts with iohexol. Iohexol appears to be a superior neuroangiographic contrast agent to current ionic drugs.


Subject(s)
Cerebral Angiography/methods , Contrast Media , Iodobenzoates , Triiodobenzoic Acids , Adult , Aortography/methods , Contrast Media/adverse effects , Diatrizoate Meglumine/adverse effects , Humans , Iohexol , Iothalamate Meglumine/adverse effects , Triiodobenzoic Acids/adverse effects
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