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R Kier

Publications and source records attributed to R Kier.

At least 19 recordsLinked to original sources
PubMed1999

Occult fractures of the greater tuberosity of the humerus: radiographic and MR imaging findings.

OBJECTIVE: The purpose of this study is to discuss the clinical implications of diagnosing a one-part greater tuberosity fracture on radiography and to describe associated rotator cuff findings on MR imaging. CONCLUSION: One-part greater tuberosity fractures are traditionally treated conservatively. Because clinical findings simulate those of rotator cuff abnormalities, some patients with missed or nonvisible fractures may be referred for MR imaging for further examination. In our study, MR imaging revealed no associated cuff abnormalities that required early surgery. Diagnosis of such a fracture on radiography may obviate the need for unnecessary MR imaging and arthroscopic surgery.

Female↗
PubMed1995

MRI of uterine leiomyosarcoma.

We report a case of a patient with uterine leiomyosarcoma. At MRI imaging, the patient was found to have a bilobed uterine mass with two components. While the caudal portion of the mass had the MRI appearance of a simple leiomyoma, the cephalad component showed atypical degeneration with an irregular contour. Malignant degeneration of a leiomyoma was confirmed by operative and histologic examination. We conclude that malignant degeneration should be considered on MR images of any degenerated leiomyoma showing an irregular contour.

Female↗
PubMed1994

MR diagnosis of tears of anterior cruciate ligament of the knee: importance of ancillary findings.

OBJECTIVE: Detection of tears of the anterior cruciate ligament with MR is usually based on the appearance of the ligament. However, other MR findings may be useful to establish the diagnosis. We assessed the utility of these ancillary MR findings for detecting tears and for differentiating partial from complete tears of the anterior cruciate ligament. MATERIALS AND METHODS: MR images of 68 patients who had arthroscopic correlation were retrospectively reviewed by two radiologists who did not know the arthroscopic findings. The reviewers noted the presence and location of bone bruises (nonlinear low signal in the bone marrow on T1-weighted images), assessed posterior displacement of the posterior horn of the lateral meniscus, and measured the posterior cruciate ligament angle. At arthroscopy, 39 patients had tears of the anterior cruciate ligament (24 complete, 15 partial) and 29 had intact anterior cruciate ligaments. RESULTS: The presence of bone bruising in the posterolateral tibial plateau had sensitivities of 50% and 46%, with corresponding specificities of 97% and 97% for the two reviewers. Posterior displacement of the posterior horn of the lateral meniscus had a sensitivity of 56% for both reviewers, with 100% and 97% specificities. An angle of the posterior cruciate ligament less than 105 degrees had sensitivities of 72% and 74%, with corresponding specificities of 79% and 86%. The prevalence of these findings was similar in patients with partial tears and those with complete tears. CONCLUSION: Ancillary MR imaging findings may be helpful for diagnosing tears of the anterior cruciate ligament when diagnosis based on the MR appearance of the ligament is equivocal. Ancillary findings cannot be used to differentiate patients with partial tears from those with complete tears. The presence of bone bruising in the posterior aspect of the tibial plateau and posterior displacement of the posterior horn of the lateral meniscus are highly specific for a torn anterior cruciate ligament; therefore, the presence of either of these findings should be considered strong evidence of a tear of the anterior cruciate ligament.

Adult↗
PubMed1994

CT of the iliopsoas compartment: value in differentiating tumor, abscess, and hematoma.

OBJECTIVE: The iliopsoas compartment is an extraperitoneal space defined by the iliopsoas fascia; its major components include the iliacus, psoas major, and psoas minor muscles. Distinction of neoplastic, inflammatory, and hemorrhagic conditions of the iliopsoas compartment is often difficult, whether based on clinical evaluation or CT findings. The purpose of this study was to determine specific CT features that might help differentiate these three abnormalities. MATERIALS AND METHODS: We retrospectively reviewed CT scans of 44 patients who had abnormalities of the iliopsoas compartment (15 neoplasms, 21 abscesses, and eight hematomas). Final diagnoses were established by surgical biopsy (n = 14), percutaneous biopsy (n = 18), or clinical evidence (n = 12). Diagnoses were correlated with 11 CT features to determine findings that could be used to differentiate the three abnormalities. These included enlargement of the iliopsoas muscles; extent, margination, and attenuation of the lesion; presence of gas, calcification, bone destruction, fat infiltration, and fascial disruption; and associated fluid or adenopathy. The radiologist who interpreted the scans had no knowledge of the clinical findings. RESULTS: The most reliable CT features for each condition were as follows: irregular margins, 67% sensitive, 52% specific, and 57% accurate for neoplasms; low attenuation, 100% sensitive, 43% specific, and 70% accurate for abscesses; and diffuse involvement of the entire muscle, 88% sensitive, 78% specific, and 80% accurate for hematomas. Combinations of individual CT features did not improve the ability to differentiate the three conditions. CONCLUSION: Our results show that the efficacy of CT, when scans are interpreted without knowledge of the clinical history, is poor for differentiating iliopsoas neoplasms, abscesses, and hematomas.

Adolescent↗
PubMed1994

Magnetic resonance imaging of the uterus.

MR imaging has emerged as the most accurate imaging modality for the evaluation of many conditions affecting the uterus. This technique can both define the normal internal anatomy of the uterus and monitor the physiologic responses of this organ to various endogenous and exogenous stimuli. MR imaging provides unique diagnostic information that may guide therapeutic management of developmental anomalies, adenomyosis, and endometrial carcinoma.

Endometriosis↗
PubMed1994

Magnetic resonance imaging of plantar fasciitis and other causes of heel pain.

Heel pain can be caused by disorders of either the plantar fascia, calcaneus, tendons, or adjacent nerves. Because these conditions can lead to pain located in a small area of the heel, a precise clinical diagnosis may be difficult. This article describes some of these various causes of heel pain and how MR imaging helps to characterize them.

Fasciitis↗
PubMed1993

MR imaging of foot and ankle tumors.

Twenty-one patients were referred for MR imaging of mass lesions in the foot and ankle detected initially by either palpation (15 patients) or radiographs (6 patients). In 3 cases, MRI excluded a discrete mass. In the remaining 18 patients with confirmation of mass lesions, the combination of signal features and tumor location suggested a specific diagnosis in 11 patients (61%). In 4 other cases, correlation with radiographs suggested likely diagnoses. In 3 cases, the MRI appearance was nonspecific. We conclude that the combination of signal features and tumor location at MR imaging often permits characterization of tumors of the foot and ankle.

Adolescent↗
PubMed1993

Fast spin-echo MR images of the pelvis obtained with a phased-array coil: value in localizing and staging prostatic carcinoma.

OBJECTIVE: The fast spin-echo pulse sequence allows T2-weighted MR images to be acquired more rapidly than is possible with conventional spin-echo sequences, and phased-array coils can provide a higher signal-to-noise ratio than is possible with the body coil. The combination of these methods permits higher resolution images to be obtained with more signal averages despite shorter imaging times. In this study, initial technical comparisons designed to confirm the advantage of combining fast spin-echo pulse sequences with a pelvic phased-array multicoil were followed by an assessment of the value of these methods for the localization and staging of prostatic carcinoma. SUBJECTS AND METHODS: Seventy-one men with known (60) or suspected (11) prostatic carcinoma were imaged with T2-weighted fast spin-echo pulse sequences in the axial and coronal planes with a phased array of four surface coils (multicoil) for signal reception. Four of these men also were imaged with fast spin-echo sequences and the body coil, and six of these men also were imaged with T2-weighted conventional spin echo sequences and the multicoil; image qualities achieved with these techniques were compared. The use of IV glucagon (42 of 71 studies) before fast spin-echo sequences was correlated with the subsequent presence or absence of peristaltic artifacts on MR images. MR images were analyzed for the presence or absence of prostatic cancer in the right and left sides of the gland and for evidence of spread either through the capsule, into the seminal vesicles, or to lymph nodes or bone. Findings at MR imaging were compared with results of radical prostatectomy (20), lymph node dissection without prostatectomy (seven), and biopsy (67). RESULTS: Image quality obtained with the combination of the fast spin-echo sequence with the multicoil was judged superior to that obtained with either the conventional spin-echo sequence with the multicoil or the fast spin-echo sequence with the body coil. Significant motion artifacts were noted in 45% of studies (13/29) performed without glucagon vs 7% of studies (3/42) performed with glucagon. In the 58 patients for whom information concerning the location of tumor in either the right or left side of the gland was obtained from biopsy (39) or surgery (19), MR images allowed cancer to be detected with 89% sensitivity and 77% specificity. Among the 20 patients undergoing prostatectomy and seven others undergoing lymph node dissection, MR imaging permitted high accuracies in predicting involvement of the seminal vesicles (100%), local transcapsular spread (85%), and involvement of pelvic lymph nodes (85%). CONCLUSION: Fast spin-echo imaging with a pelvic phased-array multicoil provides high-resolution images of the prostate that may obviate an endorectal coil for the detection, localization, and staging of prostatic carcinoma.

Aged↗
PubMed1992

Fast spin-echo MR imaging of the female pelvis. Part I. Use of a whole-volume coil.

In this prospective study, axial and sagittal magnetic resonance (MR) images were obtained with T2-weighted conventional spin-echo (CSE) and fast spin-echo (FSE) sequences in 34 consecutive female patients who underwent clinical pelvic MR examination at 1.5 T. The MR images from each patient were compared side by side, blindly and independently, by two radiologists experienced in MR imaging who used a standardized score sheet for anatomic and pathologic findings. The FSE sequences were rated superior significantly more often than the CSE sequences in most categories of findings (P less than .05), including overall image quality and reduction of motion artifact. The examination time for the FSE sequences was 1 minute 46 seconds versus an examination time of 9 minutes 14 seconds for the CSE sequences. (Both CSE and FSE sequences provided 18 sections.) It is concluded that the FSE sequence provides T2-weighted anatomic and pathologic information superior to that provided by the CSE sequence and requires substantially less imaging time.

Adolescent↗
PubMed1992

Multicoil high-resolution fast spin-echo MR imaging of the female pelvis.

A fast spin-echo pulse sequence was combined with multiple surface coils used simultaneously in the form of a "multicoil" in magnetic resonance imaging studies of the female pelvis. This combination allowed maximal resolution with maintenance of the signal-to-noise ratio (S/N) at an acceptable level, and the S/N with the multicoil system was substantially better than that achieved with a body coil. Excellent image quality and demonstration of anatomic detail were afforded by use of this technique.

Adolescent↗
PubMed1992

Chondromalacia patellae: diagnosis with MR imaging.

Most previous studies of MR imaging for detection of chondromalacia have used T1-weighted images. We correlated findings on axial MR images of the knee with arthroscopic findings to determine MR findings of chondromalacia patellae on T2-weighted and proton density-weighted images. The study population included 52 patients who had MR examination of the knee with a 1.5-T unit and subsequent arthroscopy, which documented chondromalacia patellae in 29 patients and normal cartilage in 23. The patellar cartilage was assessed retrospectively for MR signal and contour characteristics. MR diagnosis based on the criteria of focal signal or focal contour abnormality on either the T2-weighted or proton density-weighted images yielded the highest correlation with the arthroscopic diagnosis of chondromalacia. When these criteria were used, patients with chondromalacia were detected with 86% sensitivity, 74% specificity, and 81% accuracy. MR diagnosis based on T2-weighted images alone was more sensitive and accurate than was diagnosis based on proton density-weighted images alone. In conclusion, most patients with chondromalacia patellae have focal signal or focal contour defects in the patellar cartilage on T2-weighted MR images. These findings are absent in most patients with arthroscopically normal cartilage.

Adolescent↗
PubMed1992

Value of lipid- and water-suppression MR images in distinguishing between blood and lipid within ovarian masses.

The distinction between blood and lipid in ovarian masses on MR imaging is important in the differential diagnosis of these lesions. However, this is often difficult on routine MR images because both blood and lipid within tumors can have the same signal intensity as subcutaneous fat. Accordingly, we studied the value of lipid- and water-suppression MR images in making this distinction in 16 patients (21 lesions). As proved by surgery (six patients) or laparoscopy (10 patients), there were 16 endometriomas, one hemorrhagic leiomyosarcoma, and four lipid-containing mature cystic teratomas. The signal intensity in all 17 hemorrhagic lesions was greater than that of subcutaneous fat on lipid-suppression images and less than that of fat on water-suppression images. This compared with the signal intensity of the four lesions that contained lipid, in which the signal intensity was similar to that of subcutaneous fat on both the lipid- and water-suppression images. Thus, the lipid- and water-suppression MR images allowed an accurate distinction between the two. Our experience suggests that the appearance of blood and lipid in ovarian tumors is sufficiently different on lipid- and water-suppression MR images to allow an accurate distinction between the two. The two techniques should be useful in the differential diagnosis of such lesions by MR imaging.

Adipose Tissue↗