Digital Optical Card

Purpose:

To assess a patient-oriented digital optical card (OC) for documentation and communication of images using the analysis of breast microcalcifications to illustrate its resolution power.

Methods:

Fifty film mammograms with histologically proved clustered microcalcifications were digitized using a 5 lp/mm CCD-scanner. A region of interest containing the cluster was selected for documentation on an OC as an overview OC-image and as a magnified OC-image (5 lp/mm). The shape (spherical/nonspherical) as well as the total number of microcalcifications were quantitatively analyzed by 2 radiologists.

Results:

The detection rate for total number of overall and spherical microcalcifications using digital media was significantly reduced (p<0.01) compared to analog mammography. There were no significant differences in the detection rate of nonspherical microcalcifications between film mammograms (100%) and magnified section OC-images (92.7%). The overview OC-image revealed 72% of those calcifications (p<0.01).

Conclusion:

According to our results, this technology is not appropriate for diagnosis of breast microcalcifications, but may be a promising communication digital medium for transmitting an image/report unit to referring physicians.

[Diagnostic imaging and histopathologic correlation of gastrointestinal stromal tumors]

Gastrointestinale Stromatumoren (GIST) sind die häufigsten mesenchymalen Tumoren des Gastrointestinaltraktes. Immunhistochemisch werden sie durch die positive Reaktivität für den c-kit Rezeptor (CD117) in nahezu allen Fällen charakterisiert. Sie treten im ganzen Gastrointestinaltrakt, Mesenterium und Omentum auf, werden jedoch vorwiegend im Magen angetroffen. Das klinische Verhalten bezüglich Dignität ist oft schwer vorherzusagen. 17–25% der GIST sind maligne. Von den histopathologischen Kriterien, die für Malignität sprechen, sind der Tumordurchmesser über 5 cm und die Tumornekrosen am besten in der Bildgebung fassbar. Ebenso gelten radiologisch nachweisbare Metastasen als sicheres Zeichen der biologischen Malignität. Die Bildgebung spielt nicht nur für Lokalisation, Ausdehnung des Primärtumors und das Staging eine wichtige Rolle, sondern auch für Nachsorge und simultanen oder im Verlauf späteren Ausschluss seltener assoziierter Tumorentitäten wie das pulmonale Chondrom und das extraadrenale Paraganglion (Carney-Syndrom).

Dynamic time-resolved contrast-enhanced two-dimensional MR projection angiography of the pulmonary circulation: standard technique and clinical applications

OBJECTIVE

Time-resolved pulmonary two-dimensional MR projection angiography is a fast acquisition technique that allows the generation of dynamic projection angiograms by a method similar to that used to generate digital subtraction angiograms. MR images are obtained after subtracting the mask defined at the beginning of the sequence from later images, thus generating time-resolved continuous projection angiograms that depict the passage of a bolus through the pulmonary circulation. This article describes the application of this novel technique in three patients with pathologic conditions not previously described with this modality and two control subjects.

CONCLUSION

The analysis of the findings on dynamic time-resolved contrast-enhanced two-dimensional MR projection angiography shows that this technique is useful not only in revealing morphologic changes associated with pulmonary disorders but also in following the passage of the bolus through the cardiopulmonary circulation. The latter capability allows qualitative detection of normal or abnormal pathways and thus is potentially of value in the assessment of several pulmonary disorders.

Athletes with lower limb ischaemia

The case of a young healthy sportsman and acute exacerbation of chronic infragenicular pain is presented. Further investigation revealed an obstruction of the tibiofibular trunk due to an osteochondroma, arising from the fibula, which was immediately resected. Osteochondroma is observed in 1-2% of the population and may present with vascular complications. In young patients and athletes, leg pain may be of vascular origin due to an entrapment or compression and should always be considered.

Ultrasound demonstration of mammographically detected microcalcifications

PURPOSE

To evaluate the capabilities of breast ultrasound (US) for identifying microcalcifications in benign breast changes, in situ carcinomas, and small nonpalpable invasive carcinomas.

MATERIAL AND METHODS

Forty-six consecutive patients with 49 clustered microcalcifications detected by mammography were included in this prospective study. Patients with palpable breast lesions were excluded. Breast US was performed with knowledge of mammographic findings for presence and visibility of microcalcifications, and for parenchymal structure abnormalities. Mammographic and US findings were compared with histology.

RESULTS

Nine ductal in situ carcinomas, 2 lobular in situ carcinomas, 11 invasive carcinomas and 27 benign lesions were confirmed by histology. For all lesions, US achieved a sensitivity of 75% in the detection of microcalcifications. The detection rate for microcalcification in invasive and in situ carcinomas was 100%. In 11 cases, no microcalcifications were visible on US; they all proved to be benign on histology.

CONCLUSION

Microcalcifications in malignant lesions are reliably recognized by US. They are, however, difficult to detect in fibrocystic breast changes.

[Radiology of gastrointestinal stromal tumors (GIST) and a case of Carney syndrome]

Gastrointestinal stromal tumors (GIST) represent an extremely rare group of tumors, which are mostly of smooth muscle origin like leiomyomas, leiomyosarcomas and leiomyoblastomas. With the introduction of immunohistochemical analysis an epithelioid and an autonomic nerve variant can be distinguished. The purpose of this review is to demonstrate the image morphological appearance of these rare tumors together with the pathology based upon a retrospective analysis of five of our own cases since 1997. There are no pathognomonic imaging findings for characterizing a gastrointestinal stromal tumor; however, it should be included in the differential diagnosis if one or multiple large, round or oval, well-delineated gastrointestinal tumors occur in combination with central necrosis. Carney's syndrome is characterized by the syndromal association of a gastrointestinal stromal tumor (originally: gastric leiomyosarcoma) with an extra-adrenal paraganglioma and a pulmonary chondroma. In this rare syndrome, the radiological approach is important to diagnose or rule out the--simultaneous or consecutive--appearance of at least two of the three tumor entities (GIST, extra-adrenal paraganglioma, pulmonary chondroma).

[Quantitative CT assessment of the proximal femur. Experimental studies on its correlation with breaking load in femoral neck fractures]

PURPOSE

In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined.

METHODS

The bone mineral density of 41 random proximal human femora was estimated by single-energy quantitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm3 volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred.

RESULTS

Statistical analysis revealed a linear correlation between the trabecular bone density and the fracture load for the greater regions, with the highest value in the maximal area of the head (coefficient factor r = 0.76).

CONCLUSION

According to our data, the measurement of the trabecular bone by SE-QCT at the femoral head is a more confident adjunct than the neck or trochanteric area to predict a femoral neck fracture.

Digitization and postprocessing of plain-film radiographs for assessment of stone fragmentation after extracorporeal shockwave lithotripsy

In 50 patients treated for urolithiasis by extracorporeal shockwave lithotripsy (ESWL++), the radiographs taken before and 1 day afterward were initially assessed by conventional radiography and subsequently after standardized digitization and postprocessing. Clinical outcome and passage of stone fragments were reevaluated 3 weeks after ESWL. Using specially developed software routines, new disintegration parameters could be obtained by detecting the number of relevant minima in light-intensity distribution along the length axis of the concrement in digitized images. Comparing the digitized images before with those after ESWL, the concremental surface and axial length in digitized images on average showed no statistically significant difference. However, the number of visually and automatically detected light-intensity minima of the concrement region in digitized images obtained 1 day after ESWL was significantly higher than prior to ESWL and correlated significantly with the number of fissure lines in the conventional images. These new features in digitized images showed a high sensitivity in predicting later passage of stone fragments. Moreover, in six of the seven patients without detectable fissure lines in the early conventional radiographs but obvious signs of concretemental disintegration 3 weeks after ESWL, there was an increase in the number of light-intensity minima in the digitized images 1 day after ESWL. Our findings indicate that this method of digitization and post-processing of radiographs may improve the assessment of ESWL effectiveness by improving standardization in the analysis of all surveyed parameters and by offering new relevant disintegration measures.

Digital optical card. A promising technology for documentation and communication of images

PURPOSE

To assess a patient-oriented digital optical card (OC) for documentation and communication of images using the analysis of breast microcalcifications to illustrate its resolution power.

METHODS

Fifty film mammograms with histologically proved clustered microcalcifications were digitized using a 5 lp/mm CCD-scanner. A region of interest containing the cluster was selected for documentation on an OC as an overview OC-image and as a magnified OC-image (5 lp/mm). The shape (spherical/nonspherical) as well as the total number of microcalcifications were quantitatively analyzed by 2 radiologists.

RESULTS

The detection rate for total number of overall and spherical microcalcifications using digital media was significantly reduced (p < 0.01) compared to analog mammography. There were no significant differences in the detection rate of nonspherical microcalcifications between film mammograms (100%) and magnified section OC-images (92.7%). The overview OC-image revealed 72% of those calcifications (p < 0.01).

CONCLUSION

According to our results, this technology is not appropriate for diagnosis of breast microcalcifications, but may be a promising communication digital medium for transmitting an image/report unit to referring physicians.

[The value of a new digital laser card for image/report documentation and transmission]

The capabilities of a patient-oriented digital optical laser-card for the documentation of the image/report unit and for image transmission were assessed. 150 conventional X-rays covering the fields of urology (n = 50), traumatology (n = 50) and orthopaedics (n = 50) were digitised using a CCD scanner and subsequently transmitted to an Image-Transfer Medium (ITM) and to an optical laser-card. The image quality for the detection of relevant diagnostic parameters was evaluated by 4 radiologists and one clinician of the corresponding specialty. Based upon a total of 4740 decision readings for each method, it was found that the optical laser-card reduced the image quality significantly (p < 0.01) in comparison to the digitised ITM images in all fields. Thus, a primary diagnostic statement cannot be made based upon the images of the optical card. However, concomitant documentation of the image and opinion on the card may be used for the transmission of the radiological report, especially to external referring institutions.

[3-D CT for the demonstration of findings in compound skull injuries]

Conventional radiographs, axial CT with multiplanar 2-D and 3-D-CT reformations were obtained in 20 patients presenting with craniofacial injuries, to evaluate the capabilities of 3-D-CT. The image quality was assessed by two readers. Sagittal and oblique components as well as comminuted fractures could be detected by 3-D-CT reconstructions similarly to axial CT with 2-D reformations. Displacements over 2 mm were confidently documented by 3-D-CT images. 3-D-CT reconstructions allow an improved demonstration of rotational components of fractured fragments. 3-D-CT images are not as accurate as 2-D-CT in the primary detection of fractures in the relevant anatomic regions. Among 3-D-CT reconstructions, the lateral and partly the facial regions are adequately visualised.