3-Step didactic white matter dissection of human cerebellum: Micro-neuroanatomical training.

OBJECTIVES: A thorough understanding of cerebellum anatomy is essential in 4th ventricle approaches (more frequent in pediatric neurosurgery), avoiding relevant complications such as cerebellar mutism. The aim of the present work is to show the feasibility of a didactic dissection of human cerebellum focusing on cerebellar peduncles and dentate nucleus (DN), which are structures at high risk during these surgical procedures. MATERIAL AND METHODS: The cerebellum was dissected according to the Klingler method for white matter, using standard and specific microsurgery tools. Surgical microscope magnification (×6-×40) provided by a D.F. Vasconcellos M900 was required. A Canon EOS T7 18-55 mm digital camera was used and Adobe Lightroom Classic CC and Keynote were selected as photo enhancing software. Special methods such as LED light endoscopic transillumination were used for photographical reasons. RESULTS: DN dissection was successfully achieved and the relations between these nucleus and the cerebellar peduncles, inferior vermis and medullary velums were described. Through this three steps dissection guide (1. tentorial surface; 2. suboccipital surface; 3. 4th ventricle structures), the most relevant anatomical structures were shown and its implications in different 4th ventricle approaches were characterised. CONCLUSION: 3 D perspective provided by real specimen anatomical dissection is critical for learning neuroanatomy. LED transillumination was shown as a useful technique for the 4th ventricle structures photographic documentation which improves spatial recognition. This benefit can be applied for the study of the relations between the medullary velums and the rhomboid fossa foramina, which are permeable to light. The proposed three-steps dissection guide helps to a better understanding of human cerebellum and to gain self-confidence, allowing safer practice for neurosurgeons in all stages of their career.