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D L Janzen

Publications and source records attributed to D L Janzen.

66 records · Page 4Linked to original sources
PubMed1992

Testicular microlithiasis: sonographic and clinical features.

Eleven cases of bilateral diffuse microlithiasis of the testes were evaluated sonographically. The presence of testicular microlithiasis was coincidental to the presence of testicular neoplasms (n = 2), nontesticular malignant lesion in the abdomen or chest (n = 2), subfertility (n = 2), varicocele (n = 1), epididymitis (n = 1), testicular maldescent (n = 1), scrotal trauma (n = 1), and transient scrotal pain (n = 1). Clinical follow-up suggested that testicular microlithiasis is an asymptomatic nonprogressive condition. Sonographic examination of testicular microlithiasis shows diffuse hyperechoic nonshadowing foci measuring 1-2 mm in diameter throughout both testes. The diagnosis of testicular microlithiasis was pathologically proved in five cases. In six cases, the diagnosis was made on the basis of the sonographic appearance (n = 6), clinical information and follow-up (n = 6), and radiologic demonstration of testicular microcalcifications (n = 3). The sonographic appearance of testicular microlithiasis is specific, and we believe that biopsy or orchiectomy in these cases is unnecessary.

Adult↗
PubMed1992

Intraarticular fractures of the calcaneus: value of CT findings in determining prognosis.

The prognosis of intraarticular calcaneal fractures is variable, ranging from severe functional impairment and pain to complete return of normal function. Clinical assessment and CT scanning were performed 1-11 years after fracture in 45 patients (51 fractures) to determine the relationship between the CT findings and clinical status. Conservatively treated (n = 18) and surgically treated (n = 33) fractures were assessed. Clinical assessment included evaluation of subjective parameters (pain, activity, gait, and use of orthotics) and objective measurement of subtalar motion. CT evaluation included assessment of abnormalities in the posterior subtalar joint, loss of calcaneal height, tendon abnormalities, and calcaneocuboid joint abnormalities. A poor clinical outcome, caused by loss of subtalar motion, was more common when CT showed incongruity or degeneration of the posterior facet (p = .04) and when Bohler's angle was decreased (p = .0006). Other CT findings, such as loss of calcaneal height and tendon abnormalities, did not correlate with clinical outcome. An unexpected finding was that surgical screws were intraarticular in eight (24%) of 33 surgically treated patients; however, this finding was not significantly associated with poor clinical outcome. Our findings indicate that the CT findings of degenerative change and incongruity of the posterior subtalar joint correlate significantly with poor clinical outcome.

Adolescent↗
PubMed1990

Effects of acute coronary artery occlusion on the coronary microcirculation.

The exact microvascular site of coronary vasodilation after coronary artery occlusion has not been clearly established. We sought to determine 1) the microvascular site of recruitable vasodilator reserve after a critical stenosis as assessed by adenosine and EDTA, 2) the coronary microvascular site responsible for vasodilatation after total coronary artery occlusion, and 3) the microvascular site for recruitable vasodilator reserve after coronary artery occlusion as assessed by adenosine and EDTA. Hemodynamics and coronary epicardial microvascular diameter were measured in 33 dogs by means of intravital epiillumination microscopy at control conditions, during a critical stenosis, or 30, 60, and 120 min following coronary artery occlusion. To evaluate the site of pharmacologically recruitable vasodilator reserve, EDTA or adenosine was suffused onto the epicardial surface. After a critical stenosis EDTA dilated all sizes of microvessels, whereas adenosine only dilated small microvessels (less than 150 microns). After coronary artery occlusion there was vasodilation that was inversely proportional to the control microvascular diameter. Coronary microvascular diameter did not change during 2 h after coronary artery occlusion. In addition, intravenous or topically applied adenosine or topically applied EDTA had no additional effect on the coronary arteriolar diameter. We concluded that in response to sudden coronary artery occlusion, the coronary microvascular dilation was inversely related to the control microvascular diameter, and in contrast to the response after a critical stenosis, there was no pharmacologically recruitable vasodilator reserve to adenosine or EDTA following acute coronary artery occlusion.

Acute Disease↗
PubMedDate not supplied

Occult ankle fracture detected by an ankle effusion on plain radiography: a case report.

Subtle ankle fractures may escape detection on plain radiography. These occult fractures can cause prolonged disability and pain. We present a case of blunt ankle trauma where plain radiography failed to reveal any bony abnormalities. The recognition of an ankle effusion on plain radiographs prompted us to perform a computed tomography (CT) scan of the ankle. The CT scan demonstrated an anterior plafond fracture of the distal tibia, which required surgical fixation. Had the fracture not been identified, our patient would have been treated inappropriately for a ligament sprain. An occult fracture should be suspected if an ankle is grossly swollen after blunt trauma, and plain radiography demonstrates an effusion. In this circumstance, performance of further imaging studies, such as conventional or CT, are advised to rule out an occult ankle fracture.

Adult↗
PubMedDate not supplied

Orthosorb: a case of foreign-body reaction.

The authors present a previously unreported foreign-body reaction to poly-p-dioxanone pin fixation of a distal first metatarsal head osteotomy. The reaction was diagnosed by fine-needle aspiration under fluoroscopic guidance and computed tomography scan. The patient responded to conservative therapy and time, but, still has residual pain 11 months after the surgery.

Adult↗
PubMedDate not supplied

Blunt bowel and mesenteric injury: diagnostic performance of CT signs.

PURPOSE: Our goal was to determine the sensitivity and specificity of various CT signs of blunt bowel and mesenteric injury. METHOD: The CT findings of 31 patients with blunt abdominal trauma were retrospectively assessed by three observers in consensus. All patients had laparotomy within 24 h of CT. The study group consisted of 19 patients with surgically proven bowel and/or mesenteric injury. The control group consisted of 12 traumatized patients who had no bowel or mesenteric injury. The CT signs assessed were presence, location, and extent of intraperitoneal fluid, extraluminal air, bowel wall thickening, bowel wall discontinuity, mesenteric streaking, and mesenteric hematoma. RESULTS: In the 12 cases of bowel injury (9 transmural injury, 3 partial thickness injury), the CT sign of bowel wall thickening had sensitivity of 50% and specificity of 84% and the CT sign of bowel wall discontinuity had sensitivity of 58% and specificity of 95%. Extraluminal air was a specific but relatively insensitive sign of transmural bowel injury (sensitivity 44%, specificity 100%). In the 13 patients with mesenteric injuries, the CT sign of mesenteric hematoma had sensitivity of 54% and specificity of 94%. Isolated mesenteric streaking was a less specific sign of mesenteric injury (sensitivity 77%, specificity 44%). The finding of peritoneal fluid with no visible solid organ injury was a useful sign of bowel or mesenteric injury, occurring in 11 of 19 (58%) study patients and none of the controls (p < 0.001). CONCLUSION: Bowel wall thickening, bowel wall discontinuity, extraluminal air, and mesenteric hematoma are reasonably specific CT signs of bowel and mesenteric injury following blunt abdominal trauma. The presence of a moderate to large volume of intraperitoneal fluid without visible solid organ injury is an important sign of bowel or mesenteric injury.

Abdominal Injuries↗
PubMedDate not supplied

Malignant fibrous histiocytoma of soft tissue imaging with emphasis on MRI.

Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma in adults. This pictorial essay describes and illustrates the clinical, pathologic, and radiologic features of MFH. The cross-sectional imaging features on CT and MRI are emphasized in relation to the diagnosis and staging of MFH.

Adult↗
PubMedDate not supplied

Metal artifact reduction sequence: early clinical applications.

Artifact arising from metal hardware remains a significant problem in orthopedic magnetic resonance imaging. The metal artifact reduction sequence (MARS) reduces the size and intensity of susceptibility artifacts from magnetic field distortion. The sequence, which is based on view angle tilting in combination with increased gradient strength, can be conveniently used in conjunction with any spin-echo sequence and requires no additional imaging time. In patients with persistent pain after femoral neck fracture, the MARS technique allows visualization of marrow adjacent to hip screws, thus enabling diagnosis or exclusion of avascular necrosis. Other applications in the hip include assessment of periprosthetic soft tissues after hip joint replacement surgery, postoperative assessment after resection of bone tumors and reconstruction, and localization of unopacified methyl methacrylate cement prior to hip arthroplasty revision surgery. In the knee, the MARS technique allows visualization of structures adjacent to implanted metal staples, pins, or screws. The technique can significantly improve visualization of periprosthetic bone and soft-tissue structures even in patients who have undergone total knee arthroplasty. In patients with spinal fixation hardware, the MARS technique frequently allows visualization of the vertebral bodies and spinal canal contents. The technique can be helpful after wrist fusion or screw fixation of scaphoid fractures.

Adult↗