[Relevance of disaster and deployment medicine for medical students : A pilot study based on an interdisciplinary lecture series]. / Relevanz der Einsatz- und Katastrophenmedizin für Medizinstudierende : Eine Pilotevaluation im Rahmen einer interdisziplinären Vorlesungsreihe.

BACKGROUND: The global rise of conflicts and catastrophes causes new challenges for western healthcare systems. There are obvious parallels between civilian disaster medicine and military combat care. The integration of disaster and deployment medicine into the medical curriculum thus seems necessary. OBJECTIVE: What do medical students think about disaster and deployment medicine as part of the curriculum? Does participation in a voluntary disaster medicine course affect their view? MATERIAL AND METHODS: While participating in an extracurricular lecture series on disaster and deployment medicine students (group 1) were asked about their personal views and prior experience in disaster medicine (20 questions). Students who did not attend the lecture (group 2) functioned as the control group. The statistical evaluation was performed descriptively and using Student's t test for independent subgroups. RESULTS: The questionnaire was completed by 152 students (group 1: n = 78, group 2: n = 74). Only 10 students in group 1 and none in group 2 felt they had received an adequate amount of teaching in the field of disaster medicine. Medical students in both groups considered disaster medicine to be inadequately represented in the medical curriculum (group 1: 64% and group 2: 66%). Both groups were in favor of further expanding teaching in the field of disaster medicine (group 1: 72%, group 2: 54%, p = 0.001) and the development of e­learning tools (group 1: 73%, group 2: 72%). DISCUSSION: The medical students questioned considered disaster and deployment medicine to be an integral part of the curriculum. Despite some statistical differences between the two groups, the survey showed that medical students possess a great interest in disaster medicine. Both groups were in favor of further integrating e­learning tools. A regular inclusion of disaster and deployment medicine into the spectrum of medical student teaching is warranted.

[Long-term liver damage due to trauma]. / Spätfolgen von Lebertraumen.

Severe trauma has a major influence on the visceral organs, especially on the liver. Splanchnic hypotension leads to necrosis of the bile duct cells as well as to damage to hepatocytes. Furthermore, the liver is a very immunologically active organ so that damage to the liver can increase the amount of proinflammatory cytokines. The major complication of post-traumatic damage to the liver is secondary sclerosing cholangitis (SCC) a highly progressive disease for which there is no sufficient therapy except liver transplantation. Therefore it is very important to put all efforts into avoiding posttraumatic liver damage from the very beginning. A sophisticated resuscitation therapy is the most important aspect. Direct peritoneal volume resuscitation is a promising possibility to improve perfusion of the visceral organs. Other possibilities are substitution with 17beta-estradiol as a strongly vasoactive hormone with a positive effect on liver perfusion and interleukin-10 as modulator of the immune reaction caused by the liver.

[Age- and gender-related distribution of bone mineral density and mechanical properties of the proximal humerus]. / Alters- und geschlechtsabhängige Knochenmineraldichteverteilung und mechanische Eigenschaften des proximalen Humerus.

PURPOSE: To evaluate age- and gender-related mechanical properties and bone mineral density (BMD) of the proximal humerus at different levels and regions. MATERIALS AND METHODS: Mechanical indentation testing, DXA, QCT, pQCT and the radiogrammetry (Cortical Index, CI) were carried out in 70 freshly harvested humeri from 46 human cadavers (23 females, 23-males; median age 70.5 years). RESULTS: In the female group, a high correlation between age and BMD was found (rho = 0.62 to -0.70, p < 0.01) with statistically significant differences between specimens of patients 69 years or younger, and 70 years or older (p < 0.05). In the group of female specimens of age 70 years or older, BMD values were found to be significantly lower compared to their male counterparts (p < 0.05). Regardless of the specimen's age, the highest BMD and bone strength were found in the proximal aspect and in the medial and dorsal regions of the proximal humerus. CONCLUSION: These findings provide an insight into the fracture mechanism of the proximal humerus and should be the basis for designing structure-oriented implants with improved implant-bone stability in osteoporotic patients.

Combined CT pulmonary angiography and venography for diagnosis of pulmonary embolism and deep vein thrombosis: radiation dose.

A major concern about combined pulmonary CT angiography (PCTA) and CT venography (CTV) refers to the additional radiation exposure to the patient. The purpose of this paper is to analyze the organ dose, the effective dose, and the gonadal dose of combined PCTA and CTV. Effective dose and gonadal dose in PCTA and CTV were calculated. Also measured was the organ doses with thermoluminescence dosimeters in six patients who underwent combined PCTA/CTV. The risk from the effective dose and gonadal dose in combined PCTA/CTV is low. Nevertheless, additional CTV increases the gonadal dose by a significant factor and use of this procedure should be limited in younger patients.

[MRI diagnosis of injuries and diseases of peroneal tendons]. / MR-Diagnostik von Verletzungen und Erkrankungen der Peronäussehnen.

Injuries of the peroneus tendons are common and both the athlete and the older population are at risk. MR imaging is a useful technique for revealing injuries of the peroneus tendons as well as showing anatomic factors associated with these lesions. This article reviews clinical factors and MR imaging characteristics of injuries of the peroneus tendons.

Contrast-enhanced color Doppler sonography for evaluation of enlarged cervical lymph nodes in head and neck tumors.

OBJECTIVE: We determined whether contrast-enhanced color Doppler sonography can differentiate benign from malignant enlarged cervical lymph nodes in head and neck tumors. SUBJECTS AND METHODS: Ninety-four enlarged lymph nodes in 39 adult patients (32 men and seven women; age range, 30-81 years) were examined with B-mode sonography and with unenhanced and contrast-enhanced color Doppler sonography. All patients had carcinoma of the oral cavity. Histologically, lymphadenitis was found in 57 nodes and metastases in 37 nodes. Geometric dimension, texture, and margin of the node and detection and location of vessels were noted. Histology and imaging findings were correlated. RESULTS: The transverse-to-longitudinal diameter ratio in combination with texture and margin analysis resulted in a correct diagnosis in only approximately 79% of the nodes. With contrast-enhanced color Doppler sonography, 86% of nodes showed vessels, and 28% of nodes showed vessels with this technique exclusively. Characteristic configurations were identified: hilar vessels with branching indicated lymphadenitis (sensitivity, 98%; specificity, 100%), and predominantly peripheral vessels indicated metastases (100%, 98%). These findings changed the diagnosis in 13 nodes, changed the therapy in four patients, and led to an incorrect diagnosis in one patient. CONCLUSION: Enlarged lymph nodes can be characterized as metastatic or inflammatory with high diagnostic accuracy on the basis of their vascular architecture as seen on contrast-enhanced color Doppler sonography.

67Ga-citrate and 99Tcm-MDP for estimating the severity of vertebral osteomyelitis.

The aim of this study was to evaluate the roles of 67Ga-citrate and 99Tcm-methylene diphosphonate (99Tcm-MDP) planar and single photon emission tomographic (SPET) imaging in patients with vertebral osteomyelitis. Thirty patients (22 females, 8 males) aged 62.7 +/- 16.4 years (mean +/- s) were enrolled prospectively between May 1995 and May 1998. The patients had been on antibiotics for 7 +/- 4 weeks prior to the study. Histology was available for all but nine patients with mild infections, who were evaluated by a combination of magnetic resonance imaging (MRI), clinical and laboratory tests. 67Ga-citrate (185 MBq) and three-phase bone (555 MBq 99Tcm-MDP) planar and SPET imaging were performed in all patients, together with MRI as a comparison. In total, 67 infectious foci were detected. Based on histology, there were four cases of severe, 13 cases of moderate and four cases of mild osteomyelitis; nine mild infections were also classified by the combination of MRI, clinical and laboratory results. Combined MRI and 67Ga-citrate SPET correctly classified all patients; MRI detected all 67 infectious foci, whereas 67Ga-citrate SPET identified 54 only. False-negative results were seen with all other modalities, especially in cases of mild and moderate infection. 67Ga-citrate SPET identified unsuspected cases of endocarditis (n = 2), paravertebral abscess (n = 1), subaxillary soft tissue abscess (n = 1) and rib osteomyelitis (n = 1). For 67Ga-citrate SPET, the target-to-background ratio was 2.24 +/- 0.31, 1.76 +/- 0.07 and 1.30 +/- 0.18 for severe, moderate and mild osteomyelitis, respectively. Significant differences were noted between severe and moderate infection (P = 0.0051) and between severe and mild infection (P < 0.0001); that between moderate and mild infection was non-significant. For 99Tcm-MDP planar and SPET imaging, and for planar 67Ga-citrate imaging, there was no correlation with severity. We conclude that 67Ga-citrate SPET is able to identify vertebral osteomyelitis and detect additional sites of infection. It can also aid in determining the severity of infection and, potentially, the response to therapy.

Role of high magnification specimen radiography in surgical and core biopsies of the breast.

The clinical relevance of a high magnification specimen radiography (HMSR) system in breast biopsies was evaluated and compared with conventional specimen radiography with a mammography system (SRM). 100 surgical biopsies of 72 patients and 248 core biopsies of 30 patients were examined in (a) maximal 20-fold HMSR in combination with storage phosphors and (b) 1.8-fold SRM using a film-screen system. Detection of calcifications/soft tissue lesions and the impact on management were evaluated. In surgical biopsies, SRM could detect only 22% of individual microcalcifications, 39% of calcified lesions and 67% of soft tissue lesions identified with HMSR. Calcifications down to 10 microns were identified with HMSR. In five biopsies, peripheral calcifications leading to additional resection were recognized only with HMSR; in three of these they were indicative of malignant tissue. In core biopsies, only 12% of individual microcalcifications seen with HMSR were identified with SRM. 52% and 16% of all cores were calcified on HMSR and SRM, respectively. Microcalcifications within cores were found only with HMSR in 41% of patients with calcified lesions. In conclusion, the better detectability of microcalcifications with HMSR led to justified additional tissue resections in surgical patients and reduced the number of core biopsies required in interventional patients.

Surgical treatment of cholangiocellular carcinoma.

Cholangiocarcinoma is a primary liver tumor arising from the small bile ducts within the liver. According to its different location, clinical features, frequency of metastases, treatment modalities and prognosis, intrahepatic cholangiocarcinoma should well be differentiated from proximal bile duct carcinoma. To date, there is no therapeutic measure with curative potential apart from surgical treatment. Partial hepatectomy is the treatment of choice. It is of overriding importance to achieve microscopically tumor-free margins. However, only few patients treated in an early stage have a prolonged recurrence-free survival or a chance for cure. Liver transplantation is not an alternative therapeutic option for unresectable cholangiocarcinoma, due to early tumor recurrence in almost all recipients. Liver transplantation has a place in preventing cholangiocarcinoma in primary sclerosing cholangitis, although the timing of replacement is still a matter of debate. Results of surgery need further improvement by adjuvant or neoadjuvant treatment protocols.

Serous adenoma of the pancreas with multiple microcysts communicating with the pancreatic duct.

The rare neoplastic cystic adenomas of the pancreas form two groups of tumors: macrocystic mucinous and microcystic serous adenomas. Both entities show specific radiologic and histologic features. Several recent case reports, however, suggest some diversity within the group of microcystic serous adenomas. We present the case of a young man operated because of epigastric pain for 12 months and a palpable microcystic tumor of the pancreatic head. Multiple cysts communicating with branches of the pancreatic duct in an alveolar-like pattern were demonstrated on endoscopic retrograde cholangiopancreatography. Histologic examination of the specimen confirmed the diagnosis of a serous adenoma of the pancreas. The tumor morphology in this case may suggest a ductal origin of microcystic serous adenomas.

Storage phosphor direct magnification mammography in comparison with conventional screen-film mammography--a phantom study.

Contact mammography with current photostimulable storage phosphors is hampered by its low spatial resolution. Detail visualization can be improved by geometric magnification radiography which enlarges small details to exceed inherent image noise. This study compares storage phosphor mammography using a dedicated direct magnification system with state-of-the-art conventional screen-film mammography. Storage phosphor direct magnification survey views (1.7x) and spot views (4x) were obtained with a prototype mammography unit providing focal spot sizes of 120-40 microns. Conventional technique screen-film survey views (1.1x) and spot views (1.8x) served as comparison. A contrast detail study and a receiver operating characteristic (ROC) analysis using an anthropomorphic breast phantom with superimposed microcalcifications was performed. Contrast detail resolution in the digital and conventional survey views were equivalent. For the spot views, contrast detail resolution was significantly higher with the digital technique (p < 0.001). ROC analysis of 400 observations demonstrated a significantly higher performance (p < 0.001) with digital images versus conventional screen-film mammograms. The area under the ROC curve (Az) in the digital survey views was 0.76 +/- 0.07 versus 0.59 +/- 0.02 in the conventional technique. In digital spot views, Az was 0.82 +/- 0.07 as compared with 0.66 +/- 0.04 in the conventional spot views. These results suggest that storage phosphor digital mammography in conjunction with direct geometric magnification technique may be superior to conventional screen-film mammography in the detection of microcalcifications.

MR imaging of mammographically detected clustered microcalcifications: is there any value?

PURPOSE: To assess the value of dynamic magnetic resonance (MR) imaging in patients with mammographically detected suspicious microcalcifications. MATERIALS AND METHODS: Sixty-three patients (age range, 31-84 years; mean age, 56 years) with mammographically suspicious clustered microcalcifications underwent dynamic MR imaging of the breast before surgical biopsy. MR imaging was performed with a 1.5-T unit and a two-dimensional fast low-angle shot sequence with a flip angle of 80 degrees. Thirty-two axial sections, 4 mm thick and without interval gaps, were acquired before and five times after administration of gadopentetate dimeglumine (dose, 0.1 mmol per kilogram of bodyweight). Histologic findings were used as the standard of reference. Any effect of MR imaging on surgical management was noted. RESULTS: Biopsy findings verified five patients with T1 invasive carcinomas, 33 with ductal carcinomas in situ, 13 with proliferative fibrocystic disease, eight with nonproliferative fibrocystic disease, and four with sclerosing adenosis. Contrast material-enhanced dynamic MR imaging had a sensitivity of 45%, a specificity of 72%, and an overall accuracy of 56% in differentiating benign from malignant microcalcifications. All invasive tumors were detected with MR imaging. In no case was surgical management altered by MR imaging findings. CONCLUSION: MR imaging of the breast is not reliable in differentiation of benign from malignant breast disease in mammographically suspicious clustered microcalcifications and has no effect on treatment.

[A new specimen radiography device with a maximum 20-fold magnification for breast diagnosis]. / Ein neues Präparatradiographiegerät mit maximal 20facher Vergrösserung für die Mammadiagnostik.

PURPOSE: A radiography system specially developed for specimen radiography and allowing maximal 20-fold magnification is presented. The efficiency of the system was tested and compared with that of conventional magnification mammography systems. METHODS: 23 surgical and 90 core biopsies of the breast were examined for detection of microcalcifications. As criteria the number of identifiable calcifications, their shape and configuration as well as tissue contrast were chosen. RESULTS: The new technique detected about 400% more microcalcifications, 200% more core and 50% more surgical biopsies containing calcifications. Thus, in a few cases, additional core biopsies were unnecessary. Moreover, this new system yielded additional information for the pathologist and surgeon concerning the exact localisation of suspicious lesions that facilitated working up specimens, or indicated additional surgical removal in special cases. CONCLUSIONS: By identification of malignant lesions not detectable with conventional magnification radiography systems, as well as a more exact localisation of suspicious lesions, false negative results may be reduced.

A comparison of conventional mammographic magnification, ultra high magnification and industrial magnification radiography in the radiographic detection of microcalcifications within core biopsies of the breast.

The objective was to compare conventional magnification radiography (CMR), ultra high magnification radiography (UHMR) and industrial magnification radiography (IMR) in the detection of microcalcifications in breast core biopsies. 440 core biopsies were examined in 1.8-fold CMR and in 7-fold UHMR using a prototype unit. A subgroup of 59 core biopsies were also examined in 10-fold IMR. Number, size, and demarcation of microcalcifications, as well as tissue contrast, were evaluated. Only 67% of the microcalcifications seen with UHMR were detected by CMR and 78% of the core biopsies showing calcifications in UHMR were calcified in CMR. Only 38% and 58% of microcalcifications verified by IMR were identified by CMR and UHMR, respectively. 47% and 63% of the core biopsies showing calcifications in IMR were calcified in CMR and UHMR, respectively. Tissue contrast of IMR was superior to both other modalities. On the other hand, increased cost and time will probably prohibit the use of IMR for specimen radiography in routine clinical examinations. In conclusion, UHMR identifies substantially more core biopsies with microcalcifications than CMR, thus potentially reducing the number of core biopsies needed for histological analysis. IMR allowed the detection of approximately 50%/160% more microcalcifications than UHMR/CMR, thus rendering it the reference mode.

Dual-phase helical CT of the liver: effects of bolus tracking and different volumes of contrast material.

PURPOSE: To evaluate the effects of tracking and volume of contrast material on dual-phase helical computed tomography (CT) of the liver. MATERIALS AND METHODS: CT was performed in 120 consecutive patients. Either 100 mL (groups 1 and 2) or 120 mL (groups 3 and 4) of contrast material was injected at a rate of 4 mL/sec. In groups 1 and 3, the scanning delay was fixed, whereas in groups 2 and 4, scanning delays were determined individually by means of a semiautomatic bolus tracking device. The arterial phase began when splenic enhancement was greater than 10 HU and ended when hepatic enhancement was greater than 20 HU, which characterized the start of the portal venous phase. RESULTS: The mean duration of the arterial phase was 11.6 (100 mL) and 12.2 seconds (120 mL). The arterial phase of the liver within the defined limits was sufficiently timed in only 16 (54%) patients in group 1, 25 (83%) in group 2, and 20 (67%) in groups 3, whereas it was significantly (P < .05) better in 28 (93%) patients in group 4. A significantly (P < .05) higher mean parenchymal enhancement in the portal venous phase (63.6 HU +/- 8.5) was obtained in group 4. CONCLUSION: Bolus tracking of a volume of 120 mL provided the most accurate results in dual-phase liver CT.

CT of retained surgical sponges (textilomas): pitfalls in detection and evaluation.

PURPOSE: Our goal was to demonstrate possible pitfalls in the CT diagnosis of retained surgical sponges (textilomas) and to evaluate the impact of gas bubbles inside a textiloma. METHOD: Thirteen patients with textilomas were investigated with CT 3 weeks to 8 years after surgery. Twelve of the 13 textilomas were removed within 3 weeks after the first CT examination. Eight samples of surgical sponges were placed in a water bath for 6 months. Serial CT was performed to document the presence and persistence of gas bubbles. RESULTS: The radiopaque marker inside the textiloma was seen in nine patients but did not lead to the diagnosis in all patients. In seven patients gas bubbles were found inside the textiloma with a typical pattern. None of these patients had an abscess formation. In vitro studies demonstrated gas bubbles in all surgical sponges scanned 1 h afterward. The number of gas bubbles was not significantly reduced after 6 months. CONCLUSION: The variable appearance of retained surgical sponges can lead to diagnostic misinterpretations. If present, typical spongiform pattern with gas bubbles is the most specific sign for the detection of textilomas but does not indicate an abscess formation.

Blurring of vessels in spiral CT angiography: effects of collimation width, pitch, viewing plane, and windowing in maximum intensity projection.

PURPOSE: Our goal was to examine the effects of collimation width (CW), pitch, viewing plane, and windowing on the display of in-plane vessels in maximum intensity projection (MIP). METHOD: A theoretical concept based on partial volume averaging of vessels was developed to describe the contents of voxels (densities) in MIP and to derive cross-sectional vessel diameters and blurring. To validate the concept and to describe the influence of pitch, a Plexiglas cone submerged in water was scanned with varying CW and pitch. Binary MIP with three representative window levels was chosen so that definitive vessel diameters could be quantitated. RESULTS: The theoretical concept correctly predicted voxel contents and blurring for CW > or = 3 mm and low pitch. For high pitch, actual blurring was larger; however, for a given table speed, blurring of the cone decreased with pitch while increasing with CW. Overall blurring was most effectively reduced by using a thin CW and the transverse viewing plane. In the transverse viewing plane, the least blurring was found using binary MIP with a low window level. On the contrary, in the longitudinal viewing plane, blurring was minimized using a window level halfway between the density of the cone and that of the surrounding water. CONCLUSION: For CW > or = 3 mm, blurring of in-plane vessels can be explained with a simple geometrical concept based on partial volume. For accurate display, the transverse viewing plane should be used, a proper windowing must be chosen, and the CW should be kept below vessel size while raising the pitch to cover a reasonable volume.