Showing papers on "Rhinal sulcus published in 2009"

An entorhinal cortex sulcal pattern is associated with Alzheimer's disease.

Abstract: Objectives: Magnetic resonance (MRI) studies rely on sulcal boundaries to delineate the human entorhinal cortex (EC) and typically show that EC size is reduced in Alzheimer's disease (AD) and a predictor of future dementia. However, it is unknown if variations in the EC sulcal patterns are associated with AD. We classified the lateral EC sulcal boundary as either a rhinal or collateral pattern and tested the hypotheses that the rhinal pattern was (1) more common in AD and (2) associated with a smaller EC size. Experimental Design: MRI was used to determine the prevalence of the rhinal and collateral EC patterns in 421 subjects (212 AD, 107 old normal (ONL), and 102 young NL (YNL). Anatomical validation studies of normal subjects were conducted at postmortem in 34 brain hemispheres and in vivo with 21 MRI volume studies. EC pattern reliability was studied with MRI in both cross-sectional and longitudinal designs. Principal Observations: The rhinal pattern was more frequent in the right hemisphere in AD (47%) compared with ONL (28%, odds ratio = 2.25, P = 0.001). EC pattern was not related to ApoE genotype. The validations showed that the EC sulcal pattern was not associated with the neuronal number, surface area, or volume of the EC. In patients with antemortem MRI studied at postmortem it was equivalently determined, that EC patterns are reliably determined on MRI and do not change with the progressive atrophy of AD. Conclusions: The data indicate that the right hemisphere rhinal pattern is over represented in AD as compared with control. However, in normal subjects the EC rhinal pattern is not associated with a diminished EC tissue size. It remains to be demonstrated if the right EC rhinal sulcus pattern association with AD reflects genetic or developmental influences. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc.

Systematization, distribution and territory of the middle cerebral artery on the brain surface in chinchilla (Chinchilla lanigera).

Abstract: Summary The aim of the present study was to analyse thirty chinchilla (Chinchilla lanigera) brains, injected with latex, and to systematize and describe the distribution and the vascularization territories of the middle cerebral artery. This long vessel, after it has originated from the terminal branch of the basilar artery, formed the following collateral branches: rostral, caudal and striated (perforating) central branches. After crossing the lateral rhinal sulcus, the middle cerebral artery emitted a sequence of rostral and caudal convex hemispheric cortical collateral branches on the convex surface of the cerebral hemisphere to the frontal, parietal, temporal and occipital lobes. Among the rostral convex hemispheric branches, a trunk was observed, which reached the frontal and parietal lobes and, in a few cases, the occipital lobe. The vascular territory of the chinchilla’s middle cerebral artery included, in the cerebral hemisphere basis, the lateral cerebral fossa, the caudal third of the olfactory trigone, the rostral two-thirds of the piriform lobe, the lateral olfactory tract, and most of the convex surface of the cerebral hemisphere, except for a strip between the cerebral longitudinal fissure and the vallecula, which extended from the rostral to the caudal poles bordering the cerebral transverse fissure.

Study on the microsurgical anatomy of supracerebellar transtentorial approach to the posterior mediobasal temporal region

Abstract: Objective To investigate the exposure area, anatomical structures and position relation-ship of supracerebellar transtentorial (SCTT) approach to the posterior mediobasal temporal region in order to provide the evidence for clinical application. Methods Mimetic procedure of the SCTT approach to the posterior mediobasal temporal region was performed on 5 Chinese adult cadaveric heads (10 sides). Red sili- cone was injected through carotid and vertebral artery, blue silicone was injected through jugular vein. The exposure area, anatomical structures and position relationship of sulcus, gyrus and arteries or veins in the posterior mediobasal temporal region were observed under operating microscope. Three cases with tumors lo- cated in the posterior mediobasal temporal region were selected and treated via the SCTT approach, and the surgical effect and prognosis were observed. Results The SCTT approach provided a direct path to the pos- terior mediobasal temporal region and exposed the posterior parahippocampal gyrus, anterior lingual gyrus and fusiform gyrus in all cadaveric heads. The P3 segment of posterior cerebral artery (PCA) and its subtemporal branches could be reached. The rhinal sulcus and collateral sulcus were present but not consistent in all 5 cadaveric heads (10 sides). The parahippocampal gyrus was separated from the fusiform gyrus by the rhinal sulcus anteriorly and by the collateral sulcus posteriorly. The lingual gyrus was separated from the parahip- pocampal gyrus by the anterior calcarine sulcus. The isthmus of cingula gyrus and the anterior lingual gyrusjoined with the posterior parahippocampal gyrus respectively. The fusiform gyrus was seperated from the inferior temporal gyrus by the occipitotemporal sulcus. In all 5 cadaveric heads (10 sides), the arte- rial supply of posterior mediobasal tempo- ral region mainly came from the subtem-poral branches of PCA. The anterior and posterior inferior temporal branches of common temporal artery, and middle and posterior inferior temporal arteries which all originating from P2 segment of PCA supplied the blood to the basitemporal in 3 heads (4 sides) and 2 heads (2 sides), respectively. The blood supply of ba- sitemporal region in 3 heads (4 sides) came from hippocampal artery, anterior and posterior inferior temporal arteries originating from PCA. The veins of the posterior mediobasal temporal region all drained into the basal vein. In 3 patients with astrocytomas, the tumors located in the posterior mediobasal temporal region were to- tally resected through the SCTT approach, and the therapeutic effect was satisfactory. Conclusion The SCTT approach provides a viable surgical route to the posterior mediobasal temporal region in the cadaveric studies. A thorough understanding of the anatomy of the SCTT approach is essential in treating the lesion in the posterior mediobasal temporal region.