Martin Neukamm

Publications of Martin Neukamm

• Intrarenal artery delineation with ultra high resolution, flat panel based, volume computerized tomography: outer limits of spatial resolution.

  Authors: Martin Neukamm, Moritz Palmowski, Soenke Bartling, Simone Schawo, Urte Rietdorf, Hans-Peter Meinzer, Markus Hohenfellner, Hans-Ulrich Kauczor, Peter Hallscheidt

  The Journal of urology. 12/2009; 182(6):2915-9.

  PURPOSE: New methods of noninvasive high resolution imaging may improve the delineation of tumor microvessels and, thus, be of significant help in surgical planning and cost-effective monitoring ofPURPOSE: New methods of noninvasive high resolution imaging may improve the delineation of tumor microvessels and, thus, be of significant help in surgical planning and cost-effective monitoring of novel anti-angiogenic therapy. We determined the maximum delineation of intrarenal microvessels with a novel flat panel based volume computerized tomography system in an experimental setting. MATERIALS AND METHODS: We prospectively evaluated 13 porcine renal specimens for intrarenal vessel delineation using a prototype gantry based, flat panel, cone beam computerized tomography system. The gantry incorporates an array of a 40 x 30 cm(2) CsI amorphous silicon flat panel detector consisting of a 2,048 x 1,536 matrix. After catheterizing the renal artery with a 5Fr end hole catheter a contrast enhanced scan was performed using BaS as contrast medium at a dilution of 200 mg/ml. The diameter of all definable arterial branches was determined using a software tool based on Medical Imaging and Interaction Toolkit, allowing semi-automatic segmentation of the vessel tree. In step 1 the vessel tree is segmented by a 3-dimensional region growing algorithm. Following its medial axis the vessel tree is extracted and converted to a representation, including the diameter of the vessels. RESULTS: In each kidney an average +/- SD of 47,454 +/- 22,382 arterial branches could be delineated. The diameter of the branches was 0.029 (mean 0.032 +/- 0.0025) to 3.444 mm (mean 1.813 +/- 0.6139) with a median of 0.263 mm. Of visible intrarenal arteries 2.7% had a vessel diameter of 0.029 mm. CONCLUSIONS: Flat panel based volume computerized tomography can visualize intrarenal microvessels down to a diameter of 0.03 mm. It may improve the assessment of renal microvessel architecture in healthy patients and in those with pathological conditions.

• Analysis of Nontarget Embolization Mechanisms During Embolization and Chemoembolization Procedures.

  Authors: Rubén López-Benítez, Götz Richter, Hans-Ulrich Kauczor, Sibylle Stampfl, Juliane Kladeck, Boris Radeleff, Martin Neukamm, Peter Hallscheidt

  Cardiovascular and interventional radiology. 05/2009;

  Complications of embolization and chemoembolization remain a problem even with the development of low-profile catheter material and the introduction of new embolization agents. In recent years manyComplications of embolization and chemoembolization remain a problem even with the development of low-profile catheter material and the introduction of new embolization agents. In recent years many new embolization materials have become available for clinical use, so the possibilities and limitations of these new materials must be understood to allow safe and effective embolization. Although up to now some scientific work has been published reporting the basic risk of embolization procedures, the underlying pathomechanism remains the object of speculation. Besides complications like drug toxicity, allergic reactions, and bleeding of the puncture site, the characteristics of embolization materials must be known to understand the potential complications of nontarget embolization and reflux of embolization material. This article gives an overview of established and new embolization materials, their potential risks, and the underlying pathophysiology.

• Metastasis to the pancreas: characterization by morphology and contrast enhancement features on CT and MRI.

  Authors: Moritz Palmowski, Nicola Hacke, Stefanie Satzl, Miriam Klauss, Moritz N Wente, Martin Neukamm, Joerg Kleeff, Peter Hallscheidt

  Pancreatology : official journal of the International Association of Pancreatology (IAP) ... [et al.]. 02/2008; 8(2):199-203.

  AIMS: To investigate the characteristics of metastasis to the pancreas using computed tomography (CT) and magnetic resonance imaging (MRI). METHODS: Twenty-two patients with metastases to theAIMS: To investigate the characteristics of metastasis to the pancreas using computed tomography (CT) and magnetic resonance imaging (MRI). METHODS: Twenty-two patients with metastases to the pancreas were examined preoperatively by MRI (7/22) and/or multidetector CT (15/22). Pre- and post-contrast images were acquired and morphology, size, and contrast enhancement of the tumor analyzed. Subsequently, all patients underwent surgery, and the histopathologic findings were compared with the imaging results. RESULTS: In 22 patients, a total of 29 metastases were found on CT and MRI. These metastases originated from renal cell carcinomas (RCC; 22/29), colorectal carcinoma (3/29), and other malignancies (4/29). The metastases differed not in size or location, but in their contrast enhancement characteristics. RCC metastases had either intense homogeneous enhancement (in small lesions) or rim enhancement (in large lesions). Outer regions of colorectal metastases showed no difference from normal pancreatic tissue, whereas the inner area showed hypo-enhancement due to central necrosis. CONCLUSION: Imaging features of metastases from RCC point to their primary origin. While they can be distinguished from primary adenocarcinoma of the pancreas, differentiation from endocrine carcinoma might be difficult. Differentiation of colorectal carcinoma remains to be investigated on larger numbers of cases.