Biomedical subjects

S J Erickson

Publications and source records attributed to S J Erickson.

At least 37 records · Page 2Linked to original sources

PubMed1996

Measurement of prostate-specific membrane antigen in the serum with a new antibody.

Work to date has identified prostate-specific membrane antigen (PSMA) as a membrane-bound glycoprotein with high specificity for prostatic epithelial cells. PSMA reacts with the monoclonal antibody 7E11.C5, which is present in serum, seminal fluid, and prostatic epithelial cells, and is increased in its expression in the presence of a hormone refractory state associated with prostatic cancer. This report confirms these results and further documents the presence of the monoclonal antibody 3F5.4G6, which reacts with the extracellular domain of PSMA. This region of PSMA is also an element present in a truncated version of the protein, so-called PSM'. Immune precipitation with either 7E11.C5 or 3F5.4G6 yields an isolated protein species that are reactive with the reciprocal antibody in Western blot analysis. Thus, 3F5.4G6 recognizes the same PSMA protein as does 7E11.C5, but at different epitopes on essentially opposite ends of the molecule. These two antibodies are well suited for use in a sandwich immunoassay, either one as a capture or detection antibody. Current work on this is underway. This report also confirms that 7E11.C5 Western blots for PSMA are negative with normal human brain tissue. The monoclonal antibody 9H10 does not react with 3F5.4G6 or with 7E11.C5 in studies conducted herein. Moreover, 3F5.4G6 reacts with PSMA found in the LNCaP cell line, but not DU-145 or PC3, which lack PSMA.

Amino Acid Sequence↗

PubMed1996

Cirsoid aneurysm treatment by percutaneous injection of sodium tetradecyl sulfate.

BACKGROUND: Cirsoid aneurysms are uncommon arteriovenous fistulas of the scalp. Surgery for these lesions can be difficult; transarterial embolization is rarely curative, while embolization of the venous pouch with permanent agents usually necessitates subsequent surgical removal of the embolic material. The ideal embolic agent would be one that is safe and effective, commercially available, and would not require subsequent removal. METHODS: We treated an arteriovenous fistula of the scalp with direct puncture and injection of sodium tetradecyl sulfate, a commercially available sclerosing agent. RESULTS: Control angiography immediately following percutaneous injection of sotradecol into the fistula showed decreased flow but not complete closure of the lesion. However, within several days of the embolization, the patient's scalp pain and mass resolved. Four months after embolization, MRA demonstrated no evidence of residual or recurrent fistula. Color doppler flow imaging demonstrated only slightly decreased vascular resistance in the distal superficial temporal artery, possibly indirect evidence of persistent micro-fistulae. Twenty-three months after the procedure, the patient continued to be asymptomatic and had no palpable lesion. CONCLUSIONS: Percutaneous injection of sotradecol can be considered as one of the treatment options for arteriovenous fistula of the scalp. Further experience is needed to compare the safety and effectiveness of sotradecol with other agents currently used in the treatment of scalp arteriovenous fistulae.

Adult↗

PubMed1996

MR imaging interpretation of the Palmer classification of triangular fibrocartilage complex lesions.

The triangular fibrocartilage complex (TFCC) is a complex anatomic and biomechanical structure. Injury to the TFCC is a recognized cause of ulnar wrist pain. The TFCC may be injured in its horizontal portion, in its peripheral portions, or at its attachments. In the Palmer classification, TFCC lesions are categorized as traumatic or degenerative. Traumatic lesions are subclassified according to the location of the injury; degenerative lesions are subclassified according to the extent of degeneration. This classification is helpful in determining the mechanism of injury and directing clinical management. Magnetic resonance (MR) imaging may be more useful than arthrography in prospective evaluation of TFCC lesions. MR images accurately demonstrate the structural abnormalities that contribute to ulnocarpal instability and pain. The presence or absence of chondromalacia is a factor in the Palmer classification and is also considered in treatment planning. However, only advanced cases of chondromalacia are reliably detected with MR imaging.

Adult↗

PubMed1996

MR imaging of the wrist: normal findings that may simulate disease.

Twenty-six normal wrists in young adults were studied with magnetic resonance (MR) imaging. The following conclusions were drawn regarding normal anatomic features: (a) Multiple slips of the abductor pollicis longus tendon simulate longitudinal tears; (b) the extensor pollicis longus and extensor carpi ulnaris tendons normally demonstrate increased signal intensity simulating tendinitis; (c) small quantities of fluid in the extensor tendon sheaths may be normal and not indicative of tenosynovitis; (d) the triangular fibrocartilage normally demonstrates increased signal intensity simulating tears at its radial and ulnar attachment sites; (e) the volar ulnocarpal ligaments are often indistinct, thereby simulating injury; and (f) the median nerve has signal intensity equivalent to that of fat, nor of muscle as commonly believed. Awareness of these normal features is critical in making the correct interpretation of MR images of the wrist.

Adult↗

PubMed1996

MR imaging of the painful wrist.

Magnetic resonance (MR) imaging is an effective method for helping determine the cause of wrist pain by demonstrating a broad spectrum of abnormalities, including those of bone, cartilage, ligaments, and tendons. MR imaging is useful in the detection, characterization, and staging of osseous injury and disease, although computed tomography provides superior detail in the depiction of bone. MR imaging may demonstrate irregular cartilage loss in noninflammatory arthropathies such as osteoarthritis, and its superior soft-tissue contrast makes it the method of choice for evaluating the synovial processes. Although arthrography remains the standard of reference in the detection of perforations of the principal intrinsic ligaments of the wrist, three-dimensional MR imaging has shown promise in depicting the small interosseous ligaments. Tendinitis, tenosynovitis, ganglia, and anatomic variants can be diagnosed and accurately assessed with MR imaging. Radiologists need to be aware of the full spectrum of wrist abnormalities and the characteristic MR imaging findings that accompany them.

Arthralgia↗

PubMed1996

Hyaline cartilage: truncation artifact as a cause of trilaminar appearance with fat-suppressed three-dimensional spoiled gradient-recalled sequences.

PURPOSE: To investigate the cause of the trilaminar appearance within hyaline cartilage observed on magnetic resonance (MR) images obtained with a fat-suppressed three-dimensional spoiled gradient-recalled sequence. MATERIALS AND METHODS: The knees of three asymptomatic volunteers were imaged with a fat-suppressed, three-dimensional, spoiled gradient-recalled sequence. The field of view, number of phase-encoding steps, and phase-encoding direction were varied. On each image, the thickness of the patellar and trochlear cartilage was measured in millimeters and divided by the pixel dimension, which effectively expressed the thickness as the number of pixels. Finally, the number of pixels was compared with the number of alternating hyperintense and hypointense lines depicted. RESULTS: The number of truncation lines increased as pixel dimension was reduced by either decreasing the field of view or increasing the number of phase-encoding steps. The accuracy for predicting more than three lines with use of an anteroposterior phase-encoding direction varied between 83% and 92%. The appearance of the cartilage was altered when phase- and frequency-encoding directions were exchanged, but truncation lines were still evident. CONCLUSION: The trilaminar appearance depicted within hyaline cartilage on MR images obtained with this sequence is predominantly attributable to truncation artifact rather than to histologic zonal anatomy.

Adult↗

PubMed1996

Defense mechanisms and adjustment in normal adolescents.

OBJECTIVE: This study compared self-perception of defense patterns with objective and independent ratings of general adjustment in normal adolescents. METHOD: Self-perception of defense utilization by 140 high school students was measured by an adolescent version of Bond's Defense Style Questionnaire. The DSM-III-R Global Assessment of Functioning Scale was used by clinicians in determining general adjustment. RESULTS: Defense style and adjustment were significantly related; greater maturity of defense style was associated with better global adjustment, and conversely, greater immaturity of defense style was associated with a lower level of functioning. CONCLUSIONS: Adolescents' self-perceived defense patterns have conscious correlates associated with general adjustment. This study extends the validity of the defense mechanism paradigm to the adolescent age group.

Adaptation, Psychological↗

PubMed1996

Magnetic resonance imaging in the evaluation of heel pain.

This study demonstrates magnetic resonance findings in 16 patients (25 heels) with heel pain. Sixteen of 25 (64%) studies demonstrated abnormalities which could be related to the etiology of their heel pain. Eleven of 16 abnormal scans demonstrated thickening of the plantar aponeurosis with associated fibrosis (7 of 11), and a tear of the flexor digitorum brevis (1 of 11). One study demonstrated changes in the heel pad consistent with fluid. The other four abnormal studies demonstrated changes thought to be consistent with bilateral fibrous calcaneonavicular coalitions, subtalar arthrosis and tenosynovitis of the posterior tibial, flexor digitorum longus, and flexor hallucis longus tendons.

Adult↗

PubMed1995

Effect of exogenous testosterone replacement on prostate-specific antigen and prostate-specific membrane antigen levels in hypogonadal men.

Previous studies have suggested that serum prostate-specific antigen (PSA) levels are under androgenic influence, especially in patients with adenocarcinoma of the prostate. PSMA (prostate-specific membrane antigen) is thought to reflect hormonal or clonal resistance or an independence with respect to testosterone regulation. The influence of testosterone on serum PSA expression in normal men is not clear. We studied the effect of exogenous testosterone administration on the serum levels of PSA and PSMA in hypogonadal men. Serial serum PSA, serum PSMA by Western blot, and serum total testosterone levels were obtained at intervals of every 2-4 weeks in 10 hypogonadal men undergoing treatment with exogenous testosterone, delivered as testosterone enanthate injection or by testosterone patch. Linear and quadratic orthogonal polynomial scores were calculated for PSMA, PSA, and testosterone. A 2-tailed, paired t-test failed to demonstrate a significant correlation between serum PSA (linear P = 0.432, quadratic P = 0.290) or PSMA (linear P = 0.162, quadratic P = 0.973) and serum testosterone levels. This study suggests that in hypogonadal men, neither PSMA nor PSA expression is testosterone-dependent.

Adult↗

PubMed1995

Comparison of prostate specific antigen, prostate specific membrane antigen, and LNCaP-based enzyme-linked immunosorbent assays in prostatic cancer patients and patients with benign prostatic enlargement.

Serum assays for prostate specific antigen (PSA; monoclonal), for prostate specific membrane antigen (PSM; Western blot), and a LNCaP/7E11.C5-based competitive enzyme-linked immunosorbent assay (ELISA) were evaluated in a small number of prostate cancer patients with localized or disseminated disease, and judged to be in clinical progression or remission based on National Prostate Cancer Project (NPCP) criteria. PSA values recognized the presence of clinical progression in localized disease (B1-C) and to a lesser degree disseminated disease (D1-D2). In contrast, to a limited degree the ELISA test recognized clinical progression mainly in disseminated disease and chiefly in stage D2. PSM values were elevated in both D1 and D2 but not in a linear fashion as observed with PSA. The ELISA and PSM results may be assessing a different clinical response to prostatic cancer than that recognized by PSA. This could reflect a developing clone of resistant prostatic cells as previously postulated. To further pursue this possibility a secondary generation of monoclonal antibodies to PSM is being developed. The ELISA levels for benign prostatic enlargement were not elevated above normal. In contrast both with PSA and PSM the assays reflected levels significantly above the normal range in benign prostatic hypertrophy (BPH).

Antibodies, Monoclonal↗

PubMed1995

MR imaging of the major carpal stabilizing ligaments: normal anatomy and clinical examples.

The integrity of the ligamentous network of the wrist is critical, as disruption of this network may result in carpal instability and pain. The extrinsic (radiocarpal) and intrinsic (intercarpal) ligaments that maintain carpal stability can be evaluated with magnetic resonance (MR) imaging. The major extrinsic ligaments are the radioscaphocapitate, radiolunotriquetral, short radiolunate, and dorsal radiocarpal ligaments. The scapholunate and lunotriquetral ligaments are the most important intrinsic ligaments and the primary wrist stabilizers. The most common causes of carpal instability are unstable fracture of the scaphoid, scapholunate dissociation, and lunotriquetral dissociation. Carpal instability can be diagnosed from the sagittal MR image that includes the capitate, lunate, and radius and from the sagittal MR image that includes the scaphoid and radius. Knowledge of the MR imaging appearances of the major carpal stabilizing ligaments and common patterns of carpal instability allows more precise diagnosis in cases of wrist pain.

Carpal Bones↗

PubMed1995

Diaphragmatic motion: fast gradient-recalled-echo MR imaging in healthy subjects.

PURPOSE: To investigate the feasibility of imaging diaphragmatic motion with a fast gradient-recalled-echo (GRE) magnetic resonance (MR) pulse sequence. MATERIALS AND METHODS: Fast GRE pulse sequences in sagittal and coronal planes were used to acquire repeated, single-level, 1.2-second scans in 10 healthy volunteers during deliberately slowed, approximate-vital-capacity breathing. Motion was analyzed subjectively by viewing the image sequences as cine loops and quantitatively by measuring the displacement of different points on the diaphragm at a workstation. RESULTS: Temporal and spatial resolutions were adequate in all subjects. Absolute excursion of the domes was 4.4 cm on the right and 4.2 cm on the left. Analysis of diaphragmatic displacement at different locations revealed a gradient of excursion that increased from anterior to middle to posterior (P < .05-.001; paired t test). Excursion of the lateral aspects was greater than that of the medial aspect (P < .001). CONCLUSION: Fast GRE MR imaging can be reliably used to demonstrate diaphragmatic motion and may prove useful in the investigation of normal and abnormal respiratory mechanics.

Adult↗

PubMed1995

Increased signal in the normal supraspinatus tendon on MR imaging: diagnostic pitfall caused by the magic-angle effect.

OBJECTIVE: Increased signal intensity within the distal portion of the supraspinatus tendon during MR imaging is a frequent observation even in healthy subjects. This finding has been variously attributed to the presence of fat, muscle, connective tissue, abnormal vascularity, or degenerative changes. More recently, the effect of tendon orientation in the static magnetic field (Bo) has been implicated. It has been shown that tendons at the magic angle of 55 degrees to Bo show markedly increased signal. This study was designed to determine the contribution of the magic-angle effect to the MR signal in the distal portion of the supraspinatus tendon. SUBJECTS AND METHODS: Five healthy volunteers were imaged in a 1.5-T unit using short TR/TE sequences in standard supine position; they were then reimaged laterally flexed at the waist to reorient the plane of the distal portion of the supraspinatus tendon by approximately 20 degrees relative to Bo. In the second part of the study, three cadaveric shoulders were similarly imaged, first in standard position and then reoriented approximately 35 degrees by simple rotation of the specimen. The supraspinatus tendon was evaluated in each subject by noting the length of the segment with increased signal and the position of this segment relative to the insertion of the tendon on the greater tuberosity. Comparisons were made for each live and cadaveric subject between neutral and rotated positions. RESULTS: Segments of increased signal changed in length and position for each live and cadaveric subject from the neutral to the reoriented position. CONCLUSION: Our study suggests that tendon orientation contributes significantly to the presence of increased signal within the supraspinatus tendon, as caused by the magic-angle effect. Failure to recognize this effect may lead to diagnostic inaccuracy when evaluating the rotator cuff on short TR/TE sequences.

Adult↗

PubMed1994

Western blot assay for prostate-specific membrane antigen in serum of prostate cancer patients.

There is a need for the development of new diagnostic tools for the early detection of prostate cancer. A candidate molecule for a new screening test is a prostate-specific membrane antigen (PSM) recognized by the monoclonal antibody 7E11.C5. We carried out studies aimed at identifying PSM in the serum of normal and benign prostatic hyperplasia (BPH) donors and patients with adenocarcinoma of the prostate, in order to judge whether the development of a serum assay using this marker was feasible. By Western blotting, we found significant levels of PSM in serum samples from prostatic cancer patients, in the seminal fluid of pooled normal donors, in BPH patients, and in normal male sera. Similar to prostate-specific antigen (PSA), PSM was present in seminal plasma in higher concentrations than in serum, and PSM levels in prostatic cancer patients were significantly higher than in normal controls. These data suggest that the development of an assay utilizing the PSM and new monoclonal antibodies directed against the antigen, could provide a feasible test for prostatic cancers.

Adenocarcinoma↗

PubMed1994

Distal biceps tendon injury: MR imaging diagnosis.

PURPOSE: To review the authors' experience with magnetic resonance (MR) imaging of patients with suspected injury of the distal biceps tendon. MATERIALS AND METHODS: Twenty-one patients with clinically suspected injury of the distal biceps tendon were evaluated with MR imaging. Surgical correlation was performed in 15 patients, and long-term clinical follow-up was performed in the remaining six cases. RESULTS: Twelve complete biceps tears, four partial tears, one brachialis rupture, and one ganglion were identified. Axial MR images were more valuable than sagittal images in accurately grading distal biceps tendon injury preoperatively. There was 100% agreement between MR imaging and surgical findings. MR imaging findings led to changes in clinical treatment plans in eight patients (38%). CONCLUSION: MR imaging is useful in the evaluation of patients with suspected distal biceps tendon injury. In particular, axial MR images of the distal biceps insertion are important for accurate grading of the injury.

Adult↗

PubMed1994

Focal masses in cirrhotic liver: CT and MR imaging features.

The development of hepatic cirrhosis triggers attempted repair through regenerative nodules of parenchyma among bands of scar tissue. Some authors believe that this regeneration initiates an evolutionary process that may lead to nodular enlargement and cellular dedifferentiation to malignancy. Both the destructive and reparative processes in cirrhosis produce changes that the radiologist must recognize when imaging the cirrhotic liver. This essay describes the CT and MR features of masses and masslike lesions in the cirrhotic liver, including the identifying characteristics and overlapping appearances of CT and MR.

Carcinoma, Hepatocellular↗

PubMed1994

Ulnar collateral ligament of the thumb: MR findings in cadavers, volunteers, and patients with ligamentous injury (gamekeeper's thumb).

OBJECTIVE: The ulnar collateral ligament bridges the ulnar aspect of the first metacarpal and the proximal phalanx and functions as a major stabilizer of the first metacarpophalangeal joint. Acute or chronic injury of this ligament is referred to as gamekeeper's thumb. The objectives of this study were to (1) determine the MR appearance of the ulnar collateral ligament of the thumb in cadavers and volunteers and (2) analyze the MR findings in patients with gamekeeper's thumb, especially with regard to the value of MR in detecting clinically significant displacement of the ligament (Stener lesion). MATERIALS AND METHODS: MR imaging of the first metacarpophalangeal joint was performed in three volunteers, two cadaveric specimens, and 11 patients with acute injury. In the patients, the mechanism of injury was an abrupt abductive force on the thumb resulting in rupture of the ulnar collateral ligament. The diagnosis was confirmed by surgery in five patients and by clinical follow-up in the remaining six. Cryomicrotome sectioning of the cadaveric tissue blocks was performed to correlate pathologic and MR findings. Images were interpreted by one radiologist. RESULTS: MR images showed rupture of the ulnar collateral ligament in all 11 patients. Prospectively, Stener lesions (n = 3) could be differentiated from non-Stener lesions (n = 8) in eight of 11 patients. Retrospectively, the correct diagnosis could be made in all 11 patients once the importance of determining the position of the ulnar collateral ligament relative to the adductor aponeurosis was understood. CONCLUSION: MR imaging of the first metacarpophalangeal joint depicts the ulnar collateral ligament and adductor aponeurosis to good advantage. It can also accurately show tears of the ulnar collateral ligament and thus be used to differentiate a rupture without significant retraction from a Stener lesion. This information is important in determining whether surgical or conservative management is indicated.

Collateral Ligaments↗

PubMed1994

Medial and lateral supporting structures of the knee. Normal MR imaging anatomy and pathologic findings.

The supporting structures of the knee can be divided into several layers: fascial boundaries, the collateral ligaments and tendons, and the joint capsule. MR imaging's ability to demonstrate these findings has helped to validate this anatomic concept. An appreciation for the organization of the medial and lateral compartments facilitates MR imaging interpretation.

Collateral Ligaments↗