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Biomedical subjects

D L Janzen

Publications and source records attributed to D L Janzen.

At least 55 records · Page 3Linked to original sources
PubMed1995

Lead "bursogram" and focal synovitis secondary to a retained intraarticular bullet fragment.

We present an unusual case in which retained lead bullet in the wrist joint dissolved and migrated into a synovial recess, producing reactive focal synovitis. The clinical presentation suggested a soft tissue mass or ganglion cyst. The radiologic findings of dense metallic fragments within a recess of the wrist joint established the correct diagnosis and excluded other causes of soft tissue masses. Radiologic recognition of retained intra-articular lead fragments is important, as the clinical features of systemic lead intoxication, lead arthopathy, or reactive focal synovitis may be subtle or misleading.

Adult↗
PubMed1995

Shoulder girdle lipomatosis.

Shoulder girdle lipomatosis is a distinct type of lipomatosis which has unique clinical and radiographic features. The MR findings reflect the pathologic findings and, in our opinion, allow the differentiation of shoulder girdle lipomatosis from other lipomatous masses on the basis of imaging findings alone.

Female↗
PubMed1995

Acute pes anserine bursitis: MR imaging.

PURPOSE: To determine the magnetic resonance (MR) imaging appearance of acute pes anserine bursitis. MATERIALS AND METHODS: Four patients (aged 40-50 years) with presumed internal derangements of the knee underwent MR imaging; at that time, collections of fluid were found in the pes anserine bursa, but no other abnormalities were noted. RESULTS: Pes anserine bursitis was clinically diagnosed in all four patients when MR findings and physical examination findings were correlated. CONCLUSION: Pes anserine bursitis has a characteristic MR appearance of fluid beneath the tendons of the pes anserinus at the medical aspect of the tibia near the joint line. Pes anserine bursitis can clinically mimic an internal derangement of the knee, which can result in the performance of unnecessary arthroscopy. MR imaging can be useful in diagnosing pes anserine bursitis and obviating surgery.

Acute Disease↗
PubMed1995

Detection of radiographically occult ankle fractures following acute trauma: positive predictive value of an ankle effusion.

OBJECTIVE: The purpose of our study was to determine if the presence of an ankle effusion on plain radiographs after acute ankle trauma is predictive of occult ankle fracture when no fracture is visible on the standard radiographic series. SUBJECTS AND METHODS: The ankle radiographs of 1153 patients with acute ankle trauma were examined for fracture and for the presence and extent of anterior and posterior capsular distension. Patients with ankle effusions but no detectable fracture subsequently underwent sagittal and coronal complex-motion tomography. RESULTS: Eleven of 33 patients with ankle effusions and otherwise normal plain radiographs had occult fractures identified with tomography. The fracture sites were as follows: osteochondral fracture of talar dome (n = 4), neck of talus (n = 1), medial malleolus (n = 1), anterior tibial rim (n = 1), posterior tibial rim (n = 1), tibial plafond (n = 1), lateral malleolus (n = 1), and anterior process of calcaneus (n = 1). The radiographic size of an ankle effusion was predictive of occult fracture. An ankle effusion measuring 13 mm or more in anterior plus posterior capsular distension had an 82% sensitivity and 91% specificity for underlying fracture in our series. The positive predictive value of an ankle effusion 13 mm or greater was 82%. CONCLUSION: The presence of an ankle effusion on plain radiographs following acute ankle trauma is suggestive of an underlying fracture. An ankle effusion of 13 mm or greater in total capsular distension has a positive predictive value of 82% for occult fracture and is a reasonable threshold to prompt additional imaging.

Adolescent↗
PubMed1995

A technique for preoperative localization of osteoid osteoma.

Preoperative localization of osteoid osteoma using a bone biopsy needle and methylene blue tissue staining is quick, inexpensive, accurate and easy to perform. This technique allows the surgeon to limit resection to the nidus of the lesion and minimal surrounding bone. No hardware is left in situ, so the surgical exposure and dissection planes are not limited by localization hardware.

Adult↗
PubMed1994

Association of glenoid labral cysts with labral tears and glenohumeral instability: radiologic findings and clinical significance.

PURPOSE: To determine the relationship between labral cysts and labral tears and glenohumeral instability. MATERIALS AND METHODS: Magnetic resonance (MR), clinical, and arthroscopic examinations of the shoulder and the surgical findings of 20 patients were correlated and retrospectively analyzed. A cystic-appearing mass adjacent to the labrum was the selection criterion for inclusion. RESULTS: MR imaging showed labral tear intimately associated with cystic-appearing mass in these 20 patients. The tear and cyst complex was located anteriorly in two patients, posteriorly in nine, and superiorly in nine. The mass extended into the spinoglenoid notch in six patients, the suprascapular notch in three, and both notches in four. Physical examination showed glenohumeral instability in the direction of the labral tear and cystic-appearing mass in 11 patients (55%). Findings at intraarticular surgery, performed in eight patients, confirmed a labral tear with communication between the joint space and the cyst. CONCLUSION: Glenoid labral cysts are associated with glenoid labral tears and shoulder instability.

Adult↗
PubMed1994

Quantification of articular cartilage in the knee with pulsed saturation transfer subtraction and fat-suppressed MR imaging: optimization and validation.

PURPOSE: To assess the reproducibility and accuracy of volumetric quantifications of articular cartilage in the knee determined with three-dimensional (3D) magnetic resonance (MR) imaging combined with pulsed saturation transfer subtraction (STS) or T1-weighted fat suppression (FS) imaging. MATERIALS AND METHODS: Eight osteoarthritic knees were imaged repeatedly with optimized STS and FS sequences. Cartilage volumes were determined from 3D reconstructions of FS and STS images and by means of water displacement of surgically retrieved tissue. RESULTS: Mean over- or underestimation of cartilage volume at STS and FS imaging was 0.40 mL +/- 0.11 (standard deviation) (8.2%) and 0.31 mL +/- 0.08 (5.9%), respectively. Intraobserver reproducibility error was 0.20-0.65 mL (3.6%-6.4%) for STS and 0.21-0.58 mL (4.2%-6.4%) for FS imaging. Interobserver error was less than 0.62 mL and 7.8%. CONCLUSION: Three-dimensional data analysis of MR images acquired with STS or FS allows accurate and reproducible volumetric quantification of articular cartilage in the knee.

Aged↗
PubMed1994

"Magic-angle" phenomenon: a cause of increased signal in the normal lateral meniscus on short-TE MR images of the knee.

OBJECTIVE: Increased signal intensity is frequently present in the upsloping, medial segment of the posterior horn of the normal lateral meniscus on routine short-TE MR images of the knee. This attribute can mimic or obscure abnormalities in this portion of the meniscus. In the present study, we examined whether this appearance could be accounted for by the "magic-angle" phenomenon resulting from the angular orientation of this meniscal segment relative to the static magnetic field. SUBJECTS AND METHODS: Fifty-eight consecutive knee MR examinations were studied. Sixteen were excluded because of frank evidence of preexisting abnormality of the lateral meniscus. In the remaining 42 examinations, the signal intensity in the medial segment of the posterior horn of the lateral meniscus on short-TE (< 20 msec) sequences was correlated with the angular alignment of this meniscal segment relative to the static magnetic field. In five asymptomatic volunteers, meniscal signal intensities were monitored as the leg was positioned in various degrees of abduction. RESULTS: Increased signal was present in the medial segment of the posterior horn of the lateral meniscus in 31 (74%) of the 42 patients. In 25 (81%) of these, this meniscal segment was oriented at 55-60 degrees. Increased signal intensity was also present in this meniscal segment in three (60%) of five asymptomatic knees imaged in the neutral position. In each of these, abduction of the leg decreased the meniscal signal by 52-80%. Pathologic evaluation of two menisci showed numerous concentrically arranged collagen fibers. CONCLUSION: Increased signal in the upsloping portion of the posterior horn of the lateral meniscus on short-TE images often is due to the magic-angle phenomenon rather than to meniscal degeneration or tear.

Adult↗
PubMed1994

Cystic lesions around the knee joint: MR imaging findings.

A wide variety of cystic lesions may be encountered in the soft tissues and bones during routine MR imaging of the knee. These lesions represent encapsulated fluid collections and exhibit low signal intensity on T1-weighted images and high signal intensity on T2-weighted images because of their high content of free water. Many lesions produce clinical features suggestive of internal derangement of the knee, so correct MR diagnosis is needed to avoid unnecessary arthroscopy and to guide specific therapy. The purpose of this essay is to illustrate the MR appearance of cystic lesions that can be found around the knee and to explain the clinical features and significance of these lesions.

Bone Cysts↗
PubMed1994

Imaging of soft-tissue sarcomas.

Soft-tissue sarcomas are encountered only infrequently, but their diagnosis is important because the long-term prognosis is usually good if the tumour is properly managed. The role of various imaging modalities in the evaluation of these neoplasms is discussed, with special emphasis on magnetic resonance imaging. The authors review the importance of imaging in tumour detection, characterization, staging and surveillance after therapy, and they emphasize the critical subject of proper biopsy technique.

Humans↗
PubMed1994

Arthrography of the contralateral, asymptomatic wrist in patients with unilateral wrist pain.

To determine the significance of arthrographic abnormalities in patients with unilateral wrist pain, the authors compared the prevalence and site of intra-articular ligament perforation in asymptomatic and symptomatic wrists of the same group of patients and correlated asymptomatic perforation with age, hand dominance and hand overuse. Thirty-seven patients (29 men and 8 women ranging in age from 19 to 61 years) who had unilateral wrist pain and positive arthrographic findings for the symptomatic wrist underwent radiocarpal arthrography of the asymptomatic wrist. Three radiologists blinded as to the clinical findings examined the images for perforation in the triangular fibrocartilage complex, the lunotriquetral ligament and the scapholunate ligament. Intra-articular ligament perforations were found in 33 (89%) of the 37 asymptomatic wrists. Seventeen (46%) of the 37 patients had symmetric sites of perforation in the two wrists. Perforation of the triangular fibrocartilage complex occurred in 22 (59%) and 19 (51%) of the symptomatic and asymptomatic wrists respectively, of the lunotriquetral ligament in 13 (35%) and 7 (19%) respectively and of the scapholunate ligament in 13 (35%) and 11 (30%) respectively. No significant correlation between asymptomatic perforation and age or hand overuse was found (chi 2 test, Fisher's exact test). The authors conclude that asymptomatic perforation is common, even in young patients, so ligament perforation is not necessarily the cause of wrist pain in patients with such pain. However, for patients with the appropriate clinical findings, arthrography can be used to confirm or exclude ligament perforation.

Adult↗
PubMed1993

Acute pulmonary complications in immunocompromised non-AIDS patients: comparison of diagnostic accuracy of CT and chest radiography.

To compare the abilities of computed tomography (CT) and radiography in detection and diagnosis of acute pulmonary complications in immunocompromised non-AIDS patients, the CT scans and radiographs of 45 immunocompromised non-AIDS patients with proven pulmonary disease and 20 normal controls were independently assessed by two observers, without knowledge of clinical or pathologic data. The observers listed the three most likely diagnoses and their degree of confidence in the first-choice diagnosis on a three-point scale. The sensitivity and specificity in detecting pulmonary complications was 100% and 98% for CT, compared to 98% and 93%, respectively, for chest radiography. In the immunocompromised patients, the first-choice diagnosis was correct in 44% of CT and 30% of radiograph readings (P < 0.01). The correct diagnosis was among the top three diagnoses in 70% of CT scans and 53% of radiograph readings (P < 0.01). Confidence level one (definite) was reached in 33% of CT scans and 10% of chest radiographs (P < 0.001). Diseases with a dominant nodular pattern had a higher occurrence of correct first-choice diagnosis (62% vs 34%, P < 0.02) and level one confidence ratings (53% vs 13%, P < 0.001) than diseases with ground-glass opacity, consolidation or irregular linear opacities. We conclude that chest radiographs and CT scans have comparable sensitivity in detecting acute pulmonary complications in immunocompromised non-AIDS patients. CT is superior to chest radiography in the differential diagnosis of acute pulmonary complications in these patients.

Acute Disease↗
PubMed1993

Saline magnetic resonance arthrography in the evaluation of glenohumeral instability.

Sixty-five patients underwent magnetic resonance (MR) shoulder arthrography. Forty-eight of these patients underwent examination under anesthesia (EUA). MR images were retrospectively evaluated for signs felt to be imaging indicators of shoulder instability, including evaluation of various capsular measurements and the presence of glenoid labral tears, as well as Hill-Sachs fractures. Statistical analysis of the results showed that no correlation between capsular indicators with EUA-documented instability was found. However, there was a statistically significant correlation between the presence of a Bankart cartilaginous deformity (p = 0.000) and Hill-Sachs fractures (p = 0.022) with EUA-documented instability. Sensitivity to labral tears was 89% and specificity was 98%, whereas Hill-Sachs fracture detection was 69% and 87%, respectively. We believe that MR saline arthrography is of benefit in the evaluation of the anterior labrum when unenhanced MR imaging is inconclusive, and we speculate on the role of MR arthrography as a primary investigative tool.

Adolescent↗
PubMed1993

Diagnostic success of bronchoscopic biopsy in immunocompromised patients with acute pulmonary disease: predictive value of disease distribution as shown on CT.

OBJECTIVE: The purpose of the study was to determine if the distribution of pulmonary opacities on CT scans could be used to predict the outcome of bronchoscopic biopsy procedures in immunocompromised non-AIDS patients with acute pulmonary complications. MATERIALS AND METHODS: Thirty-three consecutive immunocompromised patients without AIDS who had acute pulmonary complications and who had had CT, bronchoscopic biopsy procedures, and proved diagnoses were included in the study. The distribution and dominant pattern of pulmonary opacities on CT were assessed independently by two observers. The pathologic diagnoses were invasive aspergillosis (eight), Candida pneumonia (six), bronchiolitis obliterans with or without organizing pneumonia (six), drug-induced lung disease (four), Pneumocystis carinii pneumonia (four), cytomegalovirus pneumonia (three), pulmonary hemorrhage (one), and recurrent lymphoma (one). RESULTS: The results of bronchoscopic techniques established a specific diagnosis in 17 patients (52%). In the remaining 16 patients, results of bronchoscopic biopsy could not be used to establish a specific diagnosis; open lung biopsy (15 patients) or transthoracic needle biopsy (one patient) were required for diagnosis. The results of bronchoscopic procedures were diagnostic more often in patients in whom pulmonary opacities involved the central third of the lung than in patients in whom the central third was spared (70% vs 23%, p = .02). Results were diagnostic more often in cases in which the causes of acute pulmonary complications were infectious than in cases in which the causes were noninfectious (71% vs 17%, p < .005). CONCLUSION: We conclude that the presence or absence of central disease as shown by CT can be used to suggest whether results of bronchoscopic procedures in immunocompromised non-AIDS patients will be diagnostic.

Acute Disease↗
PubMed1992

Hyperdense renal cyst due to prolonged retention of iodinated contrast material: case report.

A case of a hyperdense renal cortical cyst resulting from cyst puncture and opacification 28 months previously is reported. Prolonged retention of water-soluble iodinated contrast material is an unusual cause of a hyperdense renal cyst, which has not previously been described. The findings on serial computed tomography (CT) and chemical analysis are presented and discussed.

Adult↗
PubMed1992

Organo-axial volvulus of the sigmoid colon.

A 59 year old man presented with subacute abdominal distension and diarrhea. Plain radiographs and barium enema demonstrated organo-axial volvulus of the sigmoid colon. The radiologic, surgical, and pathologic findings are presented. The radiologic differences between organo-axial volvulus and the common mesentero-axial volvulus of the sigmoid colon are discussed.

Humans↗