Staging accuracy of MRI of the prostate with special reference to the influence of the time of last ejaculation on the detection of seminal vesicle invasion.

AIM: To evaluate the Prostate Imaging Reporting and Data System, version 2.1 (PIRADS V2.1) criteria for seminal vesicle invasion (SVI) and examine whether the timing of last ejaculation influences the detection of SVI. MATERIALS AND METHODS: The study population consisted of 68 patients (34 with SVI, 34 without SVI, matching groups by age and prostate volume) who underwent PIRADS V2.1-compliant multiparametric magnetic resonance imaging (MRI; 34 at 1.5 T, 34 at 3 T). Before the examination, the time of last ejaculation (38/68 ≤ 5 days, 30/68 > 5 days) was collected via a questionnaire. The five PIRADS V2.1 criteria for SVI with subsequent overall assessment were evaluated retrospectively by two independent examiners (examiner 1 with >10 years of experience, examiner 2 with 6 months of experience) in a single-blinded fashion for all patients using a questionnaire and a six-point scale (0 = no, 1 = very likely not, 2 = probably not, 3 = possible, 4 = probable, 5 = certain). RESULTS: E1 achieved high specificity (100%) and positive predictive value (PPV; 100%) in the overall assessment, independent of the time of last ejaculation (sensitivity = 76.5%, negative predictive value [NPV] = 81%). The area under the curve (AUC) value was 0.882; for E2, it was 0.765. At ≤5 days, the AUC values of E1 and E2 differed significantly (0.867 versus 0.681, p=0.016), as did the diffusion restriction criterion (0.833 versus 0.681, p=0.028). E1 showed high AUC values independent of time. E2 had better values for all criteria at >5 days than at ≤5 days. There were no significant differences between the examiners in all observations at >5 days. CONCLUSION: The PIRADS V2.1 criteria are well suited for an experienced examiner to detect SVI independent of time point. An inexperienced examiner will benefit from patients being abstinent >5 days prior to MRI.

Prostatic Artery Embolization: Influence of Cone-Beam Computed Tomography on Radiation Exposure, Procedure Time, and Contrast Media Use.

PURPOSE: To evaluate the effect of cone-beam computed tomography (CBCT) on radiation exposure, procedure time, and contrast media (CM) use in prostatic artery embolization (PAE). MATERIALS AND METHODS: Seventy-eight patients were enrolled in this retrospective, single-center study. All patients received PAE without (group A; n = 39) or with (group B; n = 39) CBCT. Total dose-area product (DAPtotal; Gycm2), total entrance skin dose (ESDtotal; mGy), and total effective dose (EDtotal; mSv) were primary outcomes. Number of digital subtraction angiography (DSA) series, CM use, fluoroscopy time, and procedure time were secondary outcomes. PAE in group A was performed by a single radiologist with 15 years experience, PAE in group B was conducted by four radiologists with 4 to 6 years experience. RESULTS: For groups A vs. B, respectively, median (IQR): DAPtotal 236.94 (186.7) vs. 281.20 (214.47) Gycm2(p = 0.345); EDtotal 25.82 (20.35) vs. 39.84 (23.75) mSv (p = < 0.001); ESDtotal 2833 (2278) vs. 2563 (3040) mGy(p = 0.818); number of DSA series 25 (15) vs. 23 (10)(p = 0.164); CM use 65 (30) vs. 114 (40) mL(p = < 0.001); fluoroscopy time 23 (20) vs. 28 (25) min(p = 0.265), and procedure time 70 (40) vs.120 (40) min(p = < 0.001). Bilateral PAE was achieved in 33/39 (84.6%) group A and 32/39 (82.05%) group B(p = 0.761), all other patients received unilateral PAE. There were no significant differences between clinical parameters and origins of the prostatic arteries (PA) (p = 0.206-1.00). CONCLUSION: Operators with extensive expertise on PAE may not benefit from addition of CBCT to DSA runs, whereas for operators with less expertise, CBCT when used alongside with DSA runs increased the overall radiation exposure.

Image quality and safety of automated carbon dioxide digital subtraction angiography in femoropopliteal lesions: Results from a randomized single-center study.

PURPOSE: To evaluate the image quality and the safety of automated carbon dioxide (CO2) digital subtraction angiography (DSA). MATERIALS AND METHODS: Fifty patients receiving DSA for femoropopliteal peripheral arterial disease (PAD) were enrolled in this single-center prospective study. All patients received iodinated contrast media (ICM) and CO2 as a contrast agent in the same target lesion. As a primary endpoint, four raters independently evaluated the angiography images based on overall image quality, visibility of collaterals, and assessment of stenoses/occlusions. Inter-rater agreement was assessed using the intraclass correlation coefficient (ICC) and differences between the raters were evaluated using Friedmann's test. Secondary endpoints were procedure safety and patient pain assessment. RESULTS: Inter-rater agreement between CO2-DSA and ICM-DSA images was fair to excellent for overall image quality (ICC: 0.399-0.748), fair to excellent for the visibility of collaterals (ICC: 0.513-0.691), and poor to excellent for the assessment of stenoses/occlusions (ICC: -0.065-0.762). There were no significant differences between the raters. Two patients had a hematoma, one reported pain related to puncture, one became nauseous, and one vomited. No other adverse events were observed. Reported pain scores were significantly higher for CO2-DSA vs. ICM-DSA (1.25 vs. 0625; p < 0.028). CONCLUSION: CO2-DSA using automated injection system in combination with proprietary post-processing software is safe and comparable diagnostic test compared to ICM-DSA.

[Focal therapy of prostate cancer]. / Fokale Therapie des Prostatakarzinoms.

The target of focal therapy (FT) in prostate cancer (PC) is partial treatment of the prostate aiming at preserving surrounding anatomical structures. The intention is to minimize typical side effects of radical treatment options combined with local tumor control. Numerous established and new technologies are used. Results of published studies showed a good safety profile, few side effects and good preservation of functional results. Oncologic long-term data are lacking so far. Photodynamic therapy (PDT) is the only technology that has been studied in a published prospective randomized trial. The FT is challenged by the multifocality of PC; therefore, the quality of prostate biopsy, histopathological assessment as well as imaging are of paramount importance. Multiparametric magnetic resonance imaging (MRI) has gained increasing importance. The FT is experimental and should only be offered within clinical trials.

[PI-RADS 2.0 for Prostate MRI]. / Prostatadiagnostik nach PI­RADS 2.0.

The PI-RADS 2.0 classification was established by an international collaboration of the European Society of Urogenital Radiology (ESUR), the American College of Radiology (ACR), and AdMetech Foundation to globally standardize the acquisition and interpretation of multiparametric prostate magnetic resonance imaging (MRI). The PI-RADS 2.0 aims to improve the detection, localization, staging and risk stratification of patients with suspected or histologically confirmed prostate cancer. Suspicious areas on T2-weighted (T2w) MRI, diffusion-weighted MRI (DWI) and dynamic contrast-enhanced MRI (DCE-MRI) were assessed for the presence of a clinically significant prostate cancer with scale from 1 to 5 with 5 being most likely to represent clinically significant prostate cancer. The dominant sequence to detect significant prostate cancer in the peripheral zone is DWI and for the transition zone T2w images. For the local staging of prostate cancer criteria for the assessment of an extracapsular growth were formulated.

[Focal therapy for small renal masses : Observation, ablation or surgery]. / Fokale Therapie von kleinen Nierentumoren : Beobachtung, Ablation oder Operation.

BACKGROUND: The rising incidence of renal cell carcinoma, its more frequent early detection (stage T1a) and the increasing prevalence of chronic renal failure with higher morbidity and shorter life expectancy underscore the need for multimodal focal nephron-sparing therapy. DISCUSSION: During the past decade, the gold standard shifted from radical to partial nephrectomy. Depending on the surgeon's experience, the patient's constitution and the tumor's location, the intervention can be performed laparoscopically with the corresponding advantages of lower invasiveness. A treatment alternative can be advantageous for selected patients with high morbidity and/or an increased risk of complications associated with anesthesia or surgery. Corresponding risk stratification necessitates previous confirmation of the small renal mass (cT1a) by histological examination of biopsy samples. Active surveillance represents a controlled delay in the initiation of treatment. RESULTS: Percutaneous radiofrequency ablation (RFA) and laparoscopic cryoablation are currently the most common treatment alternatives, although there are limitations particularly for renal tumors located centrally near the hilum. More recent ablation procedures such as high intensity focused ultrasound (HIFU), irreversible electroporation, microwave ablation, percutaneous stereotactic ablative radiotherapy and high-dose brachytherapy have high potential in some cases but are currently regarded as experimental for the treatment of renal cell carcinoma.

Prostate Imaging--An Update.

UNLABELLED: New technical and clinical developments of sonography and magnetic resonance imaging include improved detection, localization and staging as well as active surveillance of prostate cancer. Multiparametric MRI can best answer these typical clinical questions. However, ultrasound elastography seems to be suitable for the detection of significant prostate cancer as well. The structured reporting system for multiparametric MRI of the prostate according to PI-RADS Version 1 led to improved and reproducible diagnosis of prostate cancer. The new PI-RADS Version 2 aims to minimize the limitations of Version 1 and make PI-RADS standardization more globally acceptable. KEY POINTS: The detection, staging, and active monitoring of prostate cancer are common clinical questions. The best method for answering these questions is multiparametric MRI. Ultrasound elastography also seems to be suitable for the detection of significant prostate cancer. The new PI-RADS Version 2 claims to eliminate the limitations of PI-RADS Version 1 and to allow globally recognized standardized diagnostic reporting.

[Differential diagnosis of hematuria]. / Differenzialdiagnose der Hämaturie.

Hematuria is the main symptom of many urological and nephrological diseases. In the differential diagnostics a distinction is made between painful and pain-free and between macrohematuria which is visible to the naked eye and microhematuria which is not visible. The reasons for hematuria are basically renal (glomerular) and non-renal (non-glomerular) causes. In order not to overlook early symptoms of malignant and relevant benign diseases and also to avoid excessive diagnostic tests, a differentiated approach is necessary.

[Prostate cancer]. / Prostatakarzinom.

For many clinical issues regarding prostate cancer magnetic resonance imaging (MRI) is gaining increasing importance for prostate diagnostics. The high morphological resolution of T2-weighted sequences is unsurpassed compared to other imaging modalities. It enables not only the detection and localization of prostate cancer but also allows the evaluation of extracapsular extensions. Functional MRI methods, such as diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI and proton magnetic resonance spectroscopy ((1)H-MRS) increase the specificity and to a lesser extent, the sensitivity of diagnostics. In accordance with the interdisciplinary S3 guidelines, prostate MRI is recommended for patients with at least one negative biopsy for cancer detection. According to the guidelines areas suspected of being cancerous should be selectively biopsied in addition to the systematic biopsy. The transmission of findings about the suspected tumor areas according to the structured PI-RADS classification system has proven its worth. The localization and staging of prostate carcinoma is best achieved with the help of MRI and is recommended in the S3 guidelines especially for tumors with a clinical stage cT3/4 or with a Gleason grading system score ≥8. In addition to these applications MRI is mainly used under study conditions for local recurrence or active surveillance.

Role of endorectal prostate MRI in patients with initial suspicion of prostate cancer.

PURPOSE: To evaluate the role of conventional endorectal prostate MRI in patients with initial suspicion of prostate cancer. MATERIALS AND METHODS: Ethics board approval was received for this retrospective study of 87 men who underwent 1.5-Tesla conventional prostate MRI with a combination of endorectal and body phased-array coils for suspected prostate cancer before their first systematic 12-core TRUS-guided biopsy. Three radiologists independently analyzed the images, dividing the prostate into 12 regions corresponding to the biopsy scheme and scoring each region for the presence of prostate cancer on a 5-point scale. Results were analyzed by prostate region. ROC analysis was done and descriptive statistics were calculated. The negative predictive value, specificity, sensitivity and positive predictive value were calculated using dichotomized scores (benign tissue = scores of 1 and 2; malignant tissues = scores of 3, 4, and 5). RESULTS: Biopsy revealed cancer in 47/87 patients (26 low-grade [Gleason score 6]; 21 high-grade [Gleason score ≥ 3 + 4]), and 184/1044 cores (77 low-grade and 107 high-grade) with a median of 3 positive cores per cancer patient (range 1 - 12). The areas under ROC curves were 0.65 - 0.67 for cancer detection by region overall and 0.75 - 0.76 for the detection of high-grade cancer by region. Statistic figures for the detection of all cancers/high-grade cancers by region were as follows: negative predictive value, 87.4 - 88.2 %/92.6 - 93.1 %; specificity, 72.3 - 79.4 %/71.5 - 79.8 %; sensitivity, 49.5 - 54.8 %/62.6 - 69.2 %; and positive predictive value, 29.3 - 34.0 %/29.4 - 34.7 %. CONCLUSION: In patients with suspected prostate cancer, negative MRI findings indicate the absence of high-grade prostate cancer on subsequent TRUS-guided 12-core biopsy with high probability. However, agreement between conventional 1.5-T endorectal prostate MRI and systematic 12-core TRUS-guided biopsy for the detection of prostate cancer appears to be moderate.

Dynamic contrast enhanced MRI of the prostate: comparison of gadobutrol and Gd-DTPA.

PURPOSE: To evaluate the enhancement profile of the macrocyclic contrast medium (CM) gadobutrol in comparison to linear CM Gd-DTPA in DCE-MRI of the prostate. MATERIALS AND METHODS: In total 53 patients with prostata cancer (PCa) were included, who received a radical prostatectomy after multiparametric MRI of the prostate including DCE-MRI. Using circular regions of interests normal peripheral zone (PZ) and PCa foci > 5 mm in diameter (42 and 34 foci in Gd-DTPA and gadobutrol group, respectively) were analysed in DCE-MRI. Enhancement curves (Type I, II and III) and pharmacokinetic parameters were analyzed qualitatively and quantitatively and compared using mixed linear models (two sided p-values < 0.05 were regarded significant). RESULTS: There was no significant difference in frequencies of curve types I, II or III in the normal PZ (p = 0.63) or in PCa foci (p = 0.75). PCa with a Gleason score ≥ 7 had in comparison to Gleason ≤ 6 significantly more often a Wash-Out-curve (Type III) with both CM (p = 0.02). The relative peak enhancement was in the PZ (Gd-DTPA 1.4 a. u. [1.20; 1.59], gadobutrol 1.58 a. u. [1.37; 1.78]) and in PCa foci (Gd-DTPA 1.56 a. u. [1.41; 1.71], gadobutrol 1.76 a. u. [1.59; 1.94]) significantly higher with gadobutrol (p = 0.04). The pharmacokinetic parameters Ktrans und kep were higher in PCa foci than in PZ (p < 0.0001 and p = 0.002, respectively) without significant difference of the parameter values between both CM (p = 0.65). CONCLUSION: [corrected] This study is the first systematic comparison of gadobutrol and Gd-DTPA in DCE-MRI of the prostate. The relative peak enhancement is higher using gadobutrol compared to Gd-DTPA in DCE-MRI. There was no statistically significant difference in curve types or the pharmacokinetic parameters in PCa or normal PZ between both CM.

[PI-RADS classification: structured reporting for MRI of the prostate]. / PI-RADS-Klassifikation: Strukturiertes Befundungsschema für die MRT der Prostata.

PURPOSE: To flesh out the ESUR guidelines for the standardized interpretation of multiparametric magnetic resonance imaging (mMRI) for the detection of prostate cancer and to present a graphic reporting scheme for improved communication of findings to urologists. MATERIALS AND METHODS: The ESUR has recently published a structured reporting system for mMRI of the prostate (PI-RADS). This system involves the use of 5-point Likert scales for grading the findings obtained with different MRI techniques. The mMRI includes T2-weighted MRI, diffusion-weighted imaging, dynamic contrast-enhanced MRI, and MR spectroscopy. In a first step, the fundamentals of technical implementation were determined by consensus, taking into account in particular the German-speaking community. Then, representative images were selected by consensus on the basis of examinations of the three institutions. In addition, scoring intervals for an aggregated PI-RADS score were determined in consensus. RESULTS: The multiparametric methods were discussed critically with regard to implementation and the current status. Criteria used for grading mMRI findings with the PI-RADS classification were concretized by succinct examples. Using the consensus table for aggregated scoring in a clinical setting, a diagnosis of suspected prostate cancer should be made if the PI-RADS score is 4 or higher (≥ 10 points if 3 techniques are used or ≥ 13 points if 4 techniques are used). Finally, a graphic scheme was developed for communicating mMRI prostate findings. CONCLUSION: Structured reporting according to the ESUR guidelines contributes to quality assurance by standardizing prostate mMRI, and it facilities the communication of findings to urologists.

Role of endorectal prostate MRI in patients with initial suspicion of prostate cancer.

PURPOSE: To evaluate the role of conventional endorectal prostate MRI in patients with initial suspicion of prostate cancer. MATERIALS AND METHODS: Ethics board approval was received for this retrospective study of 87 men who underwent 1.5-Tesla conventional prostate MRI with a combination of endorectal and body phased-array coils for suspected prostate cancer before their first systematic 12-core TRUS-guided biopsy. Three radiologists independently analyzed the images, dividing the prostate into 12 regions corresponding to the biopsy scheme and scoring each region for the presence of prostate cancer on a 5-point scale. Results were analyzed by prostate region. ROC analysis was done and descriptive statistics were calculated. The negative predictive value, specificity, sensitivity and positive predictive value were calculated using dichotomized scores (benign tissue = scores of 1 and 2; malignant tissues = scores of 3, 4, and 5). RESULTS: Biopsy revealed cancer in 47/87 patients (26 low-grade [Gleason score 6]; 21 high-grade [Gleason score ≥ 3 + 4]), and 184/1044 cores (77 low-grade and 107 high-grade) with a median of 3 positive cores per cancer patient (range 1 ­ 12). The areas under ROC curves were 0.65 ­ 0.67 for cancer detection by region overall and 0.75 ­ 0.76 for the detection of high-grade cancer by region. Statistic figures for the detection of all cancers/high-grade cancers by region were as follows: negative predictive value, 87.4 ­ 88.2 %/92.6 ­ 93.1 %; specificity, 72.3 ­ 79.4 %/71.5 ­ 79.8 %; sensitivity, 49.5 ­ 54.8 %/62.6 ­ 69.2 %; and positive predictive value, 29.3 ­ 34.0 %/29.4 ­ 34.7 %. CONCLUSION: In patients with suspected prostate cancer, negative MRI findings indicate the absence of high-grade prostate cancer on subsequent TRUS-guided 12-core biopsy with high probability. However, agreement between conventional 1.5-T endorectal prostate MRI and systematic 12-core TRUS-guided biopsy for the detection of prostate cancer appears to be moderate.

[Multiparametric magnetic resonance imaging of the prostate - technique and clinical applications]. / Multiparametrische Magnetresonanztomografie der Prostata - Technik und klinische Anwendungen.

Multiparametric magnetic resonance imaging (MRI) includes 1 H magnetic resonance spectroscopy, diffusion-weighted imaging, and dynamic contrast-enhanced MRI. These new MRI techniques are increasingly being used to supplement conventional T 2 and T 1-weighted MR sequences in prostate imaging. The first part of this review outlines each of these techniques, the most important diagnostic parameters, and the pathophysiological background. The characteristic features of prostate cancer and noncancerous prostate tissue as depicted with each of the three techniques are presented. The second, clinical part outlines the diagnostic applications of the three MRI techniques for the early detection and localization of prostate cancer, staging, and the identification of recurrent cancer and discusses the most recent publications in this field. The review concludes with a look at emerging clinical applications such as the evaluation of biological aggressiveness and tumor volume.

[Dynamic contrast-enhanced MRI of the prostate: comparison of two different post-processing algorithms]. / Dynamische kontrastmittelunterstützte MRT der Prostata: Vergleich von zwei Auswerteverfahren.

PURPOSE: To evaluate the usefulness of a commercially available post-processing software tool for detecting prostate cancer on dynamic contrast-enhanced magnetic resonance imaging (MRI) and to compare the results to those obtained with a custom-made post-processing algorithm already tested under clinical conditions. MATERIALS AND METHODS: Forty-eight patients with proven prostate cancer were examined by standard MRI supplemented by dynamic contrast-enhanced dual susceptibility contrast (DCE-DSC) MRI prior to prostatectomy. A custom-made post-processing algorithm was used to analyze the MRI data sets and the results were compared to those obtained using a post-processing algorithm from In vivo Corporation (Dyna CAD for Prostate) applied to dynamic T 1-weighted images. Histology was used as the gold standard. RESULTS: The sensitivity for prostate cancer detection was 78 % for the custom-made algorithm and 60 % for the commercial algorithm and the specificity was 79 % and 82 %, respectively. The accuracy was 79 % for our algorithm and 77.5 % for the commercial software tool. The chi-square test (McNemar-Bowker test) yielded no significant differences between the two tools (p = 0.06). CONCLUSION: The two investigated post-processing algorithms did not differ in terms of prostate cancer detection. The commercially available software tool allows reliable and fast analysis of dynamic contrast-enhanced MRI for the detection of prostate cancer.

Effect of butylscopolamine on image quality in MRI of the prostate.

AIM: To evaluate the impact of butylscopolamine on the quality of magnetic resonance imaging (MRI) images of the prostate. MATERIAL AND METHODS: Eighty-two MRI examinations of the prostate were retrospectively analysed. MRI was performed with a combined endorectal/body phased-array coil including proton density-weighted (PD) sequence, T1-weighted turbo spin-echo (TSE)-sequence, and T2-weighted TSE-sequences. Forty milligrams of butylscopolamine was administered intramuscularly in 31 patients (im-group) and intravenously in 30 patients (iv-group). Twenty-one patients did not receive premedication with butylscopolamine (ø-group). Overall image quality, delineation of the bowel wall, and visualization of the prostate, neurovascular bundle, and pelvic lymph nodes were evaluated qualitatively using a five-point scale (from 1=excellent to 5=non-diagnostic/structure not discernible). Motion artefacts within the endorectal coil were quantified by baseline adjusted signal intensities inside the endorectal coil area. RESULTS: Delineation of the bowel wall using the PD-sequence was significantly improved after both intramuscular and intravenous butylscopolamine administration (ø-group: 3.6+/-0.7; im-group: 2.9+/-0.7; iv-group: 2.9+/-0.7; p=0.001). However, there were no significant differences in motion artefacts measured within the endorectal coil (ø-group: 1.18+/-0.14; im-group: 1.15+/-0.11; iv-group: 1.12+/-0.06; p=0.39). There were also no significant differences in qualitative assessment of visualization of the prostate, neurovascular bundle, pelvic lymph nodes, and of overall image quality between the study groups. CONCLUSION: : In conclusion, butylscopolamine had only a small effect on image quality and is not mandatory for MRI of the prostate.

[Pharmacokinetic MRI of the prostate: parameters for differentiating low-grade and high-grade prostate cancer]. / Pharmakokinetische MRT der Prostata: Parameter zur Unterscheidung von Low-grade- und High-grade-Prostatakarzinomen.

PURPOSE: To investigate whether pharmacokinetic MRI parameters "perfusion, blood volume, mean transit time (MTT), interstitial volume, permeability, extraction coefficient, delay, and dispersion" allow the differentiation of low-grade (Gleason score < or = 6) and high-grade (Gleason score > or = 7) prostate cancer. MATERIALS AND METHOD: Forty-two patients with prostate cancer verified by biopsy (PSA 2.7 to 31.4 ng/ml) and scheduled for prostatectomy underwent MRI at 1.5 Tesla using the dynamic contrast-enhanced inversion-prepared dual-contrast gradient echo sequence (temporal resolution, 1.65 s) and a combined endorectal body phased array coil. Parametric maps were computed using a sequential 3-compartment model and the corresponding post-processing algorithms. A total of 41 areas of prostate cancer (15 low-grade, 26 high-grade cancers) in 32 patients were able to be correlated with the prostatectomy specimens and were included in the analysis. RESULTS: Low-grade prostate cancers had a higher mean blood volume (1.76 % vs. 1.64 %, p = 0.039), longer MTT (6.39 s vs. 3.25 s, p < 0.001), and lower mean permeability (2.57 min (-1) vs. 3.86 min (-1), p = 0.011) than high-grade cancers. No statistically significant difference was found for perfusion (p = 0.069), interstitial volume (p = 0.849), extraction coefficient (p = 0.615), delay (p = 0.489), and dispersion (p = 0.306). CONCLUSIONS: Blood volume, MTT, and permeability allow the differentiation of low-grade and high-grade prostate cancer. They may be used to detect cancer progression by MRI in patients managed by active surveillance.

[Oral administration of intravenous contrast media: a tasty alternative to conventional oral contrast media in computed tomography]. / Intravenöse Kontrastmittel oral appliziert: Eine wohlschmeckende Alternative zum herkömmlichen oralen Kontrastmittel in der Computertomografie.

PURPOSE: Many patients dislike oral contrast media due to their bad taste. The aim of the present study was to identify a solution that tastes better while providing the same opacification in order to offer oncological patients an alternative to the routinely used bad tasting oral contrast media. MATERIALS AND METHODS: In a single blinded, prospective clinical study, the orally administered intravenous contrast media iohexol (Omnipaque), iopromide (Ultravist), and iotrolan (Isovist) as well as the oral contrast media sodium amidotrizoate (Gastrografin) and ioxithalamate (Telebrix) were each compared to the oral contrast medium lysine amidotrizoate as the reference standard at a constant dilution. The density values of all contrast media with the same dilutions were first measured in a phantom study. The patient study included 160 patients who had undergone a prior abdominal CT scan with lysine amidotrizoate within 6 months. The patients rated their subjective taste impression on a scale of 0 (very bad) to 10 (excellent). In addition, adverse events and opacification were recorded and prices were compared. RESULTS: The phantom study revealed identical density values. Patients assigned much higher taste impression scores of 8 and 7 to iohexol and iotrolan, respectively, as compared to a score of 3 for the conventional lysine amidotrizoate (p< 0.05). Iopromide and sodium amidotrizoate did not differ significantly from lysine amidotrizoate. The opacification of all contrast media and experienced adverse events did not differ significantly. Iotrolan (ca. 120 euro/100 ml), Iohexol and Iopromide (ca. 70 euro/100 ml) are more expensive than the conventional oral contrast media (ca. 10 - 20 euro/100 ml). CONCLUSION: Orally administered solutions of non-ionic contrast media improve patient comfort due to the better taste and provide the same opacification in comparison to conventional oral contrast media. At present, their use should be limited to individual cases due to the higher costs.