The study of the microsurgical anatomy on the relationship of the claustrum with its adjacent white matter fiber tracts

Abstract

Objective The goal in this study is to investigate the microsurgical anatomy of the relationship of the claustrum with its adjacent white matter fiber tracts,and to analyze the functional implications of the findings.Methods Ten formalin - fixed human brain hemispheres were dissected using the Klingler fiber dissection technique,with the aid of an operating microscope at 4 ～25 magnification.The microsurgical anatomy of the relationship of the claustrnm with its adjacent white matter fiber tracts was observed.Results Macroscopically,we divide the claustrum into 2 parts:the dorsal claustrum and the ventral claustrum,which in humans the dorsal claustrum was posterosuperior,and the ventral claustrum was anteroinferior.The claustrum was a thin,irregular sheet of grey matter which was surrounded by several adjacent white na tter fiber tracts. The extreme capsule,external capsule,uncinate fascicle,inferior occipitofrontal fascicle were located respectively lateral,dorsal and medial,ventral to the claustrum,and the sublenticular portion of the internal capsule which runed from medial to Iateral was located posteroinferior tothe claustrum. Although the fibers from the uncinate and inferior occipitofrontal fascicles traverse and fragment the ventral claustrum,the fibers from the extreme capsule and the external capsule initiated from or terminated to the dorsal claustrum,and part of the fibers from the internal capsule traverse the posteroinferior pole of the elaustrum.The ventral claustrum was related closely with several grey matter nucleus of basilad telencephalon such as the amygdala,nucleus accumbens and substantia innominata. Conclusion The study of anatomy and function of the adjacent white matter fiber tracts of the claustrum may provide a new approach for the function of the claustrum. Key words: Claustrum; White matter fiber tracts; Insula; Network