Morphologic Variations of the Collateral Sulcus on the Mediobasal Region of the Temporal Lobe: An Anatomical Study

• Published in: World neurosurgery Vol. 118; pp. e212 - e216
• Main Authors: Ovalioglu, Aysegul Ozdemir, Ovalioglu, Talat Cem, Canaz, Gokhan, Emel, Erhan
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2018
• Subjects: Basal region of the temporal lobe; Collateral sulcus; Humans; Lateral occipitotemporal gyrus; Magnetic Resonance Imaging - methods; Microdissection - methods; Neocortex; Occipital Lobe - anatomy & histology; Occipital Lobe - diagnostic imaging; Occipital Lobe - pathology; Random Allocation; Temporal Lobe - anatomy & histology; Temporal Lobe - diagnostic imaging; Temporal Lobe - pathology; Topographic anatomy; CS; Lateral occipitotemporal gyrus; RS; Basal region of the temporal lobe; Neocortex; Collateral sulcus; Topographic anatomy; OTS
• ISSN: 1878-8750; 1878-8769; 1878-8769
• DOI: 10.1016/j.wneu.2018.06.156

The fusiform gyrus and the collateral sulcus are the anatomical structures located in the temporobasal region. In this study, the topographic anatomy of the fusiform gyrus and the collateral sulcus is detailed to make a contribution for a successful course of temporal lobe surgery. We studied the basal surface of the temporal lobes of 38 formalin-fixed adult human brain specimens. In the morphometric analysis, the distance between anterior and posterior transverse collateral sulcus and the distance between the occipitotemporal sulcus and fusiform apex were used as parameters. The topographic anatomy of collateral sulcus was identified in detail, and 4 sulcal patterns were used to classify the sulcal arrangement of basal surface of temporal lobe in each hemisphere: type 1, single-branch and unbroken collateral sulcus with no connection; type 2, continuous with the rhinal sulcus; type 3, continuous with the occipitotemporal sulcus and; type 4, continuous with both rhinal and occipitotemporal sulcus. The current study showed that type 1 was the pattern seen most frequently (42.1%, 16/38), whereas type 4 was the least (7.9%, 3/38). Overall, 63.2% (12/19) of subjects had the same sulcal pattern in both temporal lobes. The morphometric analysis showed that the mean distance between anterior and posterior transverse collateral sulcus was 50 ± 16.2 mm and the mean distance between occipitotemporal sulcus and fusiform apex was 26 ± 8.4 mm. The topographic anatomy of the collateral sulcus with its surrounding structures is detailed in this study. This study clarifies and supplements the knowledge presently available to help develop a more feasible surgical concept. •The collateral sulcus is an important landmark, in terms of selective amygdalohippocampectomy.•The most frequent sulcal pattern is type 1: single-branch CS with no connection with rhinal sulcus or OTS.•The least frequent pattern we encountered is type 4: CS, connected to both rhinal sulcus and occipitotemporal sulcus.