The Histopathologic Reaction of Rabbit Lungs after Intrabronchial Application of Contrast Agents

PURPOSE: The aim of this study was to determine a safe gastrointestinal contrast agent that could be used in various clinical situations where there is a risk of aspiration using a rabbit model. MATERIALS AND METHODS: 30 healthy white rabbits were used. The rabbits were divided into 5 groups containing six animals each, one control group (anesthesia only) and 4 groups receiving various contrast agents [Solotop (Barium sulphate suspension), Gastrografin (Sodium and meglumine amidotrizoate), and Telebrix (Meglumine ioxitalamate), Visipaque (Iodixanol)]. The contrast agents were injected selectively into a main bronchus via a catheter inserted under fluoroscopy guidance. The rabbits were sacrificed either 1 day or 7 days after injecting the contrast agents, and the tissue reaction of the bronchi and lungs were examined both macro- and microscopically. The level of alveolar septal thickening, peribronchiolar lymphocytic infiltration, pulmonary congestion and edema, inflammatory exudate in the alveoli or bronchiolar lumina, microabscess formation, necrosis, pigmentation of materials injected, and fibropurulent pleurisy were evaluated and graded according to the severity as follows: no change, mild, moderate, marked in degree. RESULTS: The common microscopic findings were alveolar septal thickening and peribronchiolar lymphocytic infiltration. Pulmonary congestion and edema, inflammatory exudate in the alveoli or bronchiolar lumina were observed in 21 out of 24 rabbits receiving the contrast agents. Pigmentation of the materials injected was observed only in the group receiving Solotop. An inflammatory exudate in the alveoli and bronchiolar/bronchial lumina, microabscess formation, and necrosis were noted in most groups, but was more frequent and severe in the group receiving Gastrografin. CONCLUSION: The histopathological reactions of the rabbit lungs after the intrabronchial application of a contrast agent showed variable degrees of inflammatory reactions. Gastrografin produced most severe and extensive reaction, Solotop and Telebrix a moderate reaction, and Visipaque a minimal reaction. Therefore, a non-ionic dimeric contrast agent such as Visipaque may be the safest contrast agent in the lung when a GI tract examination is performed in clinical situations where there is a risk of aspiration.

Assessment of Mesenteric Vascular Steno-occlusive Lesion in Acute Mesenteric Ischemia: Comparison between CT Angiography and Digital Subtraction Angiography

PURPOSE: Acute mesenteric ischemia (AMI) is one of the most dramatic abdominal emergencies. The most common cause of AMI is a thrombo-embolism of the mesenteric artery or vein. The aim of this study was to evaluate the feasibility of CT angiography for evaluating mesenteric vascular steno-occlusive lesion in AMI. MATERIALS AND METHODS: Fifteen patients with clinically and angiographically proven AMI underwent a two-phase CT. The CT angiographic images were reconstructed using a 3D rendering algorithm, such as the maximum intensity projection and volume-rendering. All the CT angiographic images were reviewed with respect to stenosis or occlusion of mesenteric vessel by the consensus of two radiologists, and were correlated with the findings of digital subtraction angiography. RESULTS:Digital subtraction angiography (DSA) visualized 60 mesenteric vessels including the superior mesenteric artery (n=15) and vein (n=15), and the inferior mesenteric artery (n=15) and vein (n=15). DSA showed steno-occlusive lesions in 16 mesenteric vessels (13 superior mesenteric arteries, two superior mesenteric veins, and one inferior mesenteric artery). CT angiography detected steno-occlusive lesions in 16 mesenteric vessels (12 superior mesenteric arteries, one superior mesenteric vein, and three inferior mesenteric arteries). The sensitivity, specificity, and accuracy of CT angiography for evaluating mesenteric vascular steno-occlusive lesion were 87.5%, 95.4%, and 93.3%, respectively. CONCLUSION: CT angiography is an useful adjunct to abdominal CT in an AMI setting on account of its ability to detect the causes of AMI such as a steno-occlusive lesion of the mesenteric vessel.

Three-Dimensional Computed Tomographic Angiography with Volume Rendering Technique in the Evaluation of Intracranial Aneurysms: Comparison with Three-Dimensional Digital Subtraction Angiography

PURPOSE: The author compared three-dimensional computed tomographic angiography with combined volume rendering technique (3D-CTA VR) with three-dimensional digital subtraction angiography (3D-DSA) in the detection and characterization of intracranial aneurysms, in order to assess the diagnostic capability of 3D-CTA VR. MATERIALS AND METHODS: This study included 50 patients with suspected intracranial aneurysm who underwent both 3D-CTA VR and 3D-DSA, and who were subsequently confirmed as having aneurysms by intracranial operation or other neurointerventional procedures. The detectability and the characteristics of the aneurysms, such as their aneurysmal neck, direction, and vasospasm of the adjacent vessels, were evaluated retrospectively. RESULTS: Sixty-five intracranial aneurysms were detected through surgery or other interventional procedures. 3D-DSA was more sensitive (96.92%) than 3D-CTA VR in the detection of the aneurysms. All of the aneurysms that were more than 3mm in size were detected with both techniques. 3D-DSA failed to reveal one posterior communicating artery aneurysm, while 3D-CTA VR missed three aneurysms. The aneurysmal necks were clearly visualized in 58 of 61 aneurysms (95.1%) on 3D-CTA VR, but all of the aneurysmal necks(100%) were clearly identified on 3D-DSA. CONCLUSION: 3D-CTA combined with VR technique showed good sensitivity for the depiction of intracranial aneurysms greater than 3 mm in size, and its usefulness in characterizing the aneurysms for surgical or endovascular treatment planning was equal to or less than that of 3D-DSA.

Interpretation of C tract in the D-Loop of Mitochondrial DNA / 대한법의학회지

The D-loop of mitochondrial DNA contain C tracts(homopoymeric cytosines) in the positions of 16183 -16193, 303 -315, 568 -573 of GI 1944628 of NCBI. When the sequence of these positions are analyzed, the sequencing reactions or their signals after the C tract were abruptly decreased and cannot clarify the nucleotide signals in many cases. It is hard to characterize of the C tract. To characterize the C tract, we tried to analyze the sequence of clone and amp-length polymorphism with silver stain after amplification of small fragments including C tract of 16183 -16193 and 303-315.These results were compared with the results of characterization of nucleotides after separation of each nucleotide signal from the electropherogram which were increased in the Y axis to intensify the small overlapped signals using CHROMAS program. All methods we tried showed similar pattern of heteroplasmies of homopolymeric cytosines. Conclusively, it is not necessary to try resequencing reaction after cloning or amp-length polymorphism using silver stain. Intensification of the small overlapped signals in Y axis and separation of each signal is enough method to characterize the C tract.