Atlas of Forensic Pathology

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CHAPTER 31 Special Dissections

terminalis and sectioning parallel to the muscle bundle, the sinoatrial node can be identified. Often, the sinoatrial nodal artery is visible grossly (Figure 31.8A-D). The atrioventricular node can be isolated using two approaches: from the right ventricular surface, utilizing Koch triangle, or from the left ventricular side. On the left ventricular side, the atrioventricular node is immediately subjacent to the non-coronary cusp of the aortic valve (Figure 31.9A and B). If the non-coronary cusp and underlying myo cardium is excised and serially sectioned perpendicular to the cusp, the atrioventricular node can be obtained. In the examination of the sinoatrial or atrioventricular node, fixation of the excised block of tissue in formalin prior to sectioning will facilitate the process. DISSECTION OF THE PARATHYROID GLANDS WHEN PERFORMED As long as the neck organs are removed, the parathyroid glands should be examined in any given autopsy; however, if there is a history of renal failure or of hypercalcemia then the examination is more likely to yield findings. HOW PERFORMED The superior parathyroid glands can be easily identified. With reflection of the fascia at the transition from the larynx to the trachea between the thyroid gland and the trachea on the posterior surface, the glands can be identified (Figure 31.10A and B).

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B

C D Figure 31.8. Dissection of the sinoatrial node. The sinoatrial node is on the superior vena cava side of the crista terminalis ( A ; indicated by arrow in C ). The crista terminalis is removed ( B and C ) and serially sectioned ( D ). The sinoatrial nodal artery can often be visualized (arrow) ( D ). The sinoatrial node is around this vessel. Copyright © Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. 2023