Hungarian Radiology

[Ways of imaging the expression of vascular endothelial growth factor and its receptor]


OCTOBER 20, 2009

Hungarian Radiology - 2009;83(03)

[The vascular endothelial growth factor (VEGF) and its receptors (VEGFR) signal-transduction pathway play a key role in the regulation of angiogenesis. It was originally isolated as a selective mitogen for endothelial cells and as a powerful vascular permeability increasing factor. The vascular imaging techniques make the quantification and localization of blood vessels possible. They have been used to assess blood flow, oxygenation, and vascular permeability. Also, they can be used to examine the molecular and cellular difference in the vascular wall. To evaluate tumour vascularity, a multimodality approach is expanding. VEGF as the primary mediator for vascular-permeability is indirectly measurable with DCE-MRI (dynamic contrastenhanced MRI). MRI investigation can determine the ratio of deoxyhemoglobin/oxyhemoglobin in order to localize the hypoxic regions in vivo (BOLD [blood oxygen-level dependent] sequence and OMRI [Overhauser MRI]). In molecular MRI (mMRI), contrast agent-mediated alteration of tissue relaxation times can allow for the detection and localization of molecular disease markers. To localize the expression of VEGFR with SPECT and PET, antibodies and VEGF isoforms can be marked with isotopes. VEGFR is an excellent candidate for targeted ultrasound imaging since it is almost exclusively expressed on activated endothelial cells. Optical imaging is a relatively cheap method suitable so far primarily for small animal studies.]



Further articles in this publication

Hungarian Radiology

[Portal embolisation prior to liver resection]

MÓZES Péter, MÉSZÁROS György, TÓTH Judit, SÁPY Péter

[INTRODUCTION - By partial embolisation of the vena portae the number of the patients suitable for radical liverresection can be enhanced, the safety of the operation can be increased, the subsequent results improved. The method is based on the experience that when blocking the circulation of the portal system in special segments of the liver, the other part of the organ tries to substitute the functional deficiency by hypertrophy. Vena portae embolisation is justified in cases when the liver substance remaining after the planned operation is critically small. PATIENTS AND METHODS - The authors carried out vena portae embolisation at Debrecen University Medical and Health Science Centre since October 2003 on six patients. Assessments were made studying the volume of the whole liver, the lobe affected by embolisation and that of the unaffected lobe, by CT-volumetry. The average age of the patients (four men and two women) was 63 years (51-67 years). The hepatic tumour was an extended metastasis localised to one lobe in five cases, and HCC in one of the patients. In each case we carried out closing the right lobe’s portal system. RESULTS - In five cases the left lobe showed increase following the portal embolisation of the right lobe intended to be removed. On the average four-six weeks passed between the two CT-examinations. The growth of the left lobe was an average of 42% (min. 11.8%, max. 75.6%). CONCLUSION - In selected patients the embolisation of the vena portae system of the tumorous liver-segments is a suitable method for enlargening the size of the liver substance remaining after an extensive resection.]

Hungarian Radiology

[“Indian summer” at Sárvár 14th Congress of the Society of Hungarian Radiographers - Sárvár, September 17-19th, 2009.]


Hungarian Radiology

[Omental infarction diagnosed with ultrasonography]


[INTRODUCTION - Omental infarction is a rare entity, mimicking symptoms of acute appendicitis. Although omental infarction has typical morphology, both on sonography and CT, it is rarely diagnosed preoperatively. CASE REPORT - A 4-years-old girl presenting with right lower quadrant abdominal pain underwent abdominal sonography, which revealed normal appendix and a superficial hyperechoic solid mass at the site of the pain. The patient underwent laparotomy which confirmed the presumed diagnosis of partial omental necrosis. The necrotic tissue was resected, the appendix was normal. After uneventful postoperative course the child became symptom -free and was discharged. CONCLUSION - The sonomorphology of omental infarction is typical. The suspicion of this entity should be considered as a differential diagnosis of appendicitis, especially if normal appendix can be visualized.]

Hungarian Radiology

[Farewell to dr. József Soós 1926-2009]


Hungarian Radiology

[Ultrasound diagnostics: method or art?]


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