M. Funke

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.

MRI in the evaluation of müllerian duct anomalies.

OBJECTIVE Müllerian duct anomalies (MDAs) result from nondevelopment or nonfusion of the müllerian ducts and occur in 1-5% of women. Accurate diagnosis of the various subtypes is of great importance as MDAs are frequently associated with a broad variety of clinical symptoms. Recently, evidence arose that MRI might play a major role in diagnosis of MDAs. We present four cases of diverse subtypes of MDAs and the corresponding MRI findings. MATERIALS AND METHODS Patients (n = 4) with clinical suspicion of MDAs were examined with MRI. Coronal and transaxial T1- and T2-weighted images were acquired. Diagnosis was made and patients were grouped according to the American Fertility Societys classification. Patients underwent laparoscopy or laparotomy in order to confirm the diagnosis. RESULTS MRI revealed MDAs in all patients. In detail, one patient was diagnosed with hypoplastic uterus, one with unicornuate uterus with a noncommunicating rudimentary horn, one with bicornuate uterus bicollis with a double vagina and one with septate uterus. MRI diagnosis was correct in all cases, as confirmed by subsequent surgical intervention. CONCLUSION MRI is a valuable tool in diagnosis of MDA subtypes. Its use will help to spare patients mutilating surgery and to prevent pregnancy-associated complications.

Magnification mammography: a comparison of full-field digital mammography and screen-film mammography for the detection of simulated small masses and microcalcifications

Abstract. The objective of this study was a comparison of a full-field digital mammography (FFDM) system and a conventional screen-film mammography (SFM) system with respect to the detectability of simulated small masses and microcalcifications in the magnification mode. All images were obtained using 1.8 times magnification. The FFDM images were obtained at radiation dose levels of 1.39, 1.0, 0.7, 0.49 and 0.24 times that of the SFM images. A contrast-detail phantom was used to compare the detection of simulated lesions using a four alternative forced-choice reader study with three readers. The correct observation ratio (COR) was calculated as the fraction of correctly identified lesions to the total number of simulated lesions. Soft-copy reading was performed for all digital images. Direct magnification images acquired with the digital system showed a lower object contrast threshold than those acquired with the conventional system. For equal radiation dose, the digital system provided a significantly increased COR (0.95) compared with the screen-film system (0.82). For simulated microcalcifications, the corresponding difference was 0.90 to 0.72. The digital system allowed equal detection to screen-film at 40% of the radiation dose used for screen film. Digital magnification images are superior to screen-film magnification images for the detection of simulated small masses and microcalcifications even at a lower radiation dose.

ECG-gated Multislice Spiral CT for Diagnosis of Acute Pulmonary Embolism

AIM The purpose of this study was to determine the feasibility of echocardiogram (ECG)-gated multi-slice CT angiography (MCTA) in patients with clinical suspicion of acute venous thromboembolism (VTE), to investigate the effect of ECG-gating on cardiac motion artefacts, and to determine the diagnostic reader agreement of ECG-gated MCTA in comparison with conventional MCTA. MATERIALS AND METHODS Forty-eight consecutive patients were prospectively enrolled and randomly underwent ECG-gated (n=25, group 1) or non-ECG-gated (n=23, group 2) eight-slice pulmonary MCTA. Image data were evaluated by three independent chest radiologists with respect to the presence or absence of emboli at different arterial levels (main, lobar, segmental, and subsegmental arteries), and with regard to cardiac motion artefacts. Statistical tests used to calculate inter-observer agreement were weighted kappa statistics, extended kappa statistics and confidence indices indicating three-reader agreement accuracy. RESULTS Twenty-seven patients (56.3%) were diagnosed to have pulmonary embolism (13 from group 1, 14 from group 2). Cardiac motion artefacts were significantly more frequent in group 2 (70% in group 2 versus 13% in group 1, p=0.0001). The overall diagnostic agreement was excellent with both MCTA techniques (three-reader confidence index for all vascular territories: 0.76 and 0.84 for groups 1 and 2, respectively (extended kappa=0.69 and 0.78, respectively); three-reader confidence index for diagnosis of VTE: 0.94 and 0.85 for groups 1 and 2, respectively (extended kappa=0.91 and 0.73, respectively), weighted kappa=0.81-0.83 and 0.92-0.95 for groups 1 and 2, respectively, and did not differ significantly between the two groups. In addition there was no significant difference of inter-observer agreement in either group at any assessed pulmonary arterial level. CONCLUSION ECG-gated pulmonary MCTA is feasible in patients with clinical suspicion of VTE. However, ECG-gated image acquisition did not influence the diagnostic reader agreement accuracy and inter-observer agreement of MCTA. Hence, it does not appear to be advantageous for the MCTA diagnosis of pulmonary embolism.

Value of Magnetic Resonance Imaging in Patients With Penile Induration (Peyronie's Disease)

Magnetic resonance imaging (MRI) is a noninvasive procedure that enables exact imaging of penile anatomy. A total of 34 patients with clinical Peyronies disease underwent palpation, ultrasound and MRI after intracavernous injection of 10 micrograms. prostaglandin E1. MRI images were obtained before and after intravenous application of gadolinium-diethylenetriaminepentaacetic acid. In 34 patients 45 plaques were palpable. Ultrasound revealed evidence of lesions in 66.6% of the cases. On MRI 36 of 45 palpable plaques (80%) were detected. Not palpable or sonographically revealed indurations could be shown in 4 cases. After intravenous application of gadolinium-diethylenetriaminepentaacetic acid 4 plaques demonstrated contrast enhancement, thus indicating local inflammatory activity. The combination of clinical examination and sonography remains the method of choice for diagnosis and observation of patients with Peyronies disease. MRI enables exact imaging of penile structures but it does not provide a significant advantage over standard investigative procedures.

Flat panel detector-based volumetric CT: prototype evaluation with volumetry of small artificial nodules in a pulmonary phantom.

Purpose: To evaluate amorphous silicone-based flat panel detector volumetric CT (VCT) in volumetric assessment of small nodules in a pulmonary phantom, and to perform comparative experiments with 4-row multislice CT (MSCT). Materials and Methods: Seventy synthetic nodules (volume range (VR): 0.99–185.77 mm3; estimated diameter range (ED): 1.4–7.8 mm) were scanned in spherical shape and after iso-volumetric deformation with VCT and MSCT using 0.63 mm (MSCT I) and 1.25 mm (MSCT II) collimations. Measured volumes and percent measurement errors (PME) were compared between the 3 CT modes before and after nodule deformation. For each measurement pair before and after deformation, the post-deformation relative volumetric inaccuracy (RIA) was determined. Volume, PME, and RIA differences were tested using Wilcoxon and Friedman methods. Results: The volumes of the smallest nodules (VR = 0.99–2.83 mm3, ED = 1.4–1.9 mm) were computable only from VCT scans. In VCT, measured volumes and PMEs before and after deformation differed significantly less compared with MSCT (VCT: P = 0.06 and 0.56, respectively; MSCT I: P = 0.0012 and 0.006, respectively; and MSCT II: P < 0.0001 for measured volumes and PMEs). In VCT PMEs of 5.51–32.21 mm3 nodules (ED = 2.4–4.1 mm) before and after deformation were significantly below MSCT (VCT averages = 1.43–1.91% and 1.98–3.48%, for spherical and deformed nodules, respectively; MSCT I averages = 9.97–26.1% and 12.16–38.10%, respectively; MSCT II averages = 17.79–46.18 and 18.14–54.66%, respectively, P < 0.0001) and RIAs in VCT were significantly below MSCT (VCT: 0.50–2.62%, MSCT I: 3.35–15.97%, and MSCT II: 4.29–18.46%; P = 0.0001–0.0039). Conclusion: VCT volumetry is highly accurate in volumetry of smallest nodules with estimated diameters of 1.4–4.1 mm.

Psychoendocrine sequelae of chronic testosterone deficiency

The precise role of testosterone in regulating mood, especially in alleviating depression, remains unclear although converging evidence indicates that androgens may exert antidepressant action. A model that may potentially assist in the clarification of androgen-mediated effects on mood is the study of cryptorchid men who may grow up with varying degrees of testosterone deficiency depending on the time in their life when cryptorchism is corrected. In this report, we describe a rare case of bilateral cryptorchism that did not come to the attention of the physician to implement effective substitution with testosterone until much later in adult life. The patient developed severe and suicidal depression which responded solely to testosterone. In addition, the patient experienced a delayed but accelerated puberty without any adverse events. These observations, although based on a single case, provide strong evidence that testosterone may exert powerful antidepressant action in the absence of concomitant antidepressant agents.

Detection of renal ischemic lesions using Gd-DTPA enhanced turbo FLASH MRI: Experimental and clinical results

PURPOSE Our goal was to investigate the role of Gd-DTPA-enhanced dynamic MRI in the evaluation of renal ischemic lesions. METHOD With a turbo FLASH sequence before and after injection of Gd-DTPA, nine foxhound dogs after 60-120 min of renal ischemia underwent MR examination. In addition, five patients with a tumor in a solitary kidney were examined before and after nephron-sparing renal surgery to evaluate renal perfusion and function. The experimental and clinical findings were correlated with conventional measurements of kidney function and with histological findings. RESULTS Complete renal ischemia leads to a poor corticomedullary differentiation in Gd-DTPA-enhanced turbo FLASH MRI. The signal-intensity-versus-time plots of kidneys with significant postischemic changes show a less steep increase of signal intensity in the cortex and a steeper increase of signal intensity in the medulla than those of normal kidneys. CONCLUSION Dynamic MRI demonstrate renal morphology and reflect the functional status of renal vasculature.

Digitale Vollfeldmammographie: Vergleich zwischen radio-graphischer Direktvergrößerung und digitalem Monitorzooming

ZusammenfassungFragestellung. Es soll geklärt werden, ob und inwieweit das Zooming einer primär digital gewonnenen Röntgenmammographie die zusätzliche Anfertigung einer direkten Vergrößerungsmammographie entbehrlich macht. Methodik. Im Rahmen einer intraindividuellen Vergleichsstudie wurde bei 55 Patientinnen mit 57 Mikroverkalkungen die Aussagekraft der direkten Vergrößerungsmammographie (Faktor 1,8 [MAG1,8]) mit der nachträglich vom Monitorbild gezoomten Aufnahme (Faktor 1,8 [ZOOM1,8]) verglichen. Vier Auswerter stuften die Bildqualität ein und führten eine Charakterisierung der Verkalkungen nach der BI-RADS-Kategorisierung des American College of Radiology (ACR) durch. Ergebnisse. Histopathologisch fanden sich 16 benigne (sklerosierende Adenose, Hyperplasie, Hamartom, radiäre Narbe) und 21 maligne Veränderungen (DCIS, invasive Karzinome). Bei den restlichen 20 Patienten lagen gutartige Veränderungen vor, die im Verlauf über mehr als 2 Jahre befundkonstant waren. Die Bildqualität der direkten Vergrößerungsmammographie wurde besser eingeschätzt als die der gezoomten Aufnahme. Auch die Sensitivität der MAG1,8 war mit 97,5% der gezoomten Aufnahme (ZOOM1,8: 96,3%) geringfügig überlegen. Im Gegensatz hierzu zeigten die nachbearbeiteten Monitorbilder eine höhere Spezifität (MAG1,8: 34,3%, ZOOM1,8: 40%), einen besseren PPV (MAG1,8: 47,5%, ZOOM1,8: 49,8%) und eine günstigere Treffsicherheit (MAG1,8: 58,1%, ZOOM1,8: 61,2%). Die durchschnittliche Abweichung der BI-RADS-Kategorien lag bei 0,45 für MAG1,8 und bei 0,44 für ZOOM1,8. Schlussfolgerungen. Die digitale Aufnahmetechnik erlaubt aufgrund der Option des Monitorzoomings in aller Regel den Verzicht auf eine zusätzliche direkte Vergrößerungsmammographie. Hieraus resultieren eine weitere Verbesserung des Work-flows und ein Potenzial zur Dosisreduktion.AbstractPurpose. Our goal was to compare digital magnification mammograms with images zoomed from the digital contact mammogram in patients with microcalcifications. Patients and methods. Fifty-five patients with 57 microcalcification clusters were evaluated with a FFDM system (Senographe 2000D, GE). In addition to a digital contact mammogram, a digital direct magnification mammogram (factor 1,8 [MAG1,8]) and an image zoomed from the contact mammogram with a magnification factor of 1,8 [ZOOM1,8] were obtained in each patient. The image quality (perfect = 5 points to inadequate = 1 point) and the characterization of microcalcifications (BI-RADS 2–5) were evaluated by 4 readers. The results were compared to histopathologic findings in 35 patients (37 lesions) and follow-up in 20 patients. Results. Histopathology revealed 16 benign and 21 malignant lesions. 20 patients had benign changes verified by long-term follow-up. Image quality of direct magnification FFDM was assessed superior (4,44 points) to zoomed images (4,14 points). Sensitivity was superior for direct magnification (97,5%) in comparison to the zoomed images (96,3%). However, specificity (MAG1,8: 34,3%, ZOOM1,8: 40%), PPV (MAG1,8: 47,5%, ZOOM1,8: 49,8%) and accuracy (MAG1,8: 58,1%, ZOOM1,8: 61,2%) were better with zooming technique. Deviation steps from best BI-RADS assessment were 0,45 for MAG1,8 and 0,44 for ZOOM1,8. Conclusions. In patients with mammographic microcalcifications, monitor zooming of the digital contact mammogram is equivalent to direct magnification FFDM. Therefore, monitor zooming allows a reduction of the radiation exposure and an optimization of the work-flow.

Magnification survey and spot view mammography with a new microfocus X-ray unit: detail resolution and radiation exposure

Abstract. The aim of our study was to evaluate a mammography unit capable of magnification of up to fourfold at an equivalent or lower dose than with current systems. A prototype mammography tube with an electron-beam-focusing technology resulting in a focal spot size of 40–120 μm was combined with a highly intensifying screen-film system. To evaluate contrast-detail resolution, phantom radiographs were performed with the prototype magnification mammography system using a magnification factor of 1.7 for survey views and a magnification factor of 4.0 for spot views. They were compared with unmagnified survey views and magnification spot views (magnification factor 1.9) of a state-of-the-art mammography system. The radiation exposure was measured and mean glandular doses were calculated. The contrast-detail resolution with both prototype (m = 1.7) and conventional (m = 1.1) survey views was equivalent while the entrance dose and the mean glandular dose were approximately 50 % lower with the prototype. For spot views, the contrast-detail resolution was substantially higher for the prototype than for conventional magnification while the dose was equivalent. Dose reduction and improved detail resolution are possible with this new technology.