PubMed · 7931634
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C A Fager. 1994. Herniated lumbar disc.. https://pubmed.ncbi.nlm.nih.gov/7931634/
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An engraving displaying A General View of the Absorbent System was used as one of many plates illustrating the Lymphatics section of Andrew Fyfe's Compendium of the Anatomy of the Human Body published in 1800. It is a scaled-down version of a life-size engraving displayed in the museum of the Department of Anatomy at the University of Edinburgh, and is based on a cadaver specially dissected and injected with mercury in 1788 by Alexander Monro secundus, probably with the assistance of Fyfe, who was his 'dissector'. Only recently has the relationship between these two engravings been established, and the Figure Legend in Fyfe's Compendium now provides the missing key to the features illustrated in the life-size engraving. The source and very variable quality of some of Fyfe's other plates, both in the Lymphatics section and elsewhere in the book, are discussed.
OBJECTIVE: The microanatomic details of the foramen lacerum and surrounding region are described to clarify the relationship between the internal carotid artery and the foramen lacerum. The terminology related to these structures is reevaluated. Examples of pathological abnormalities restricted to the foramen lacerum region are presented to document the clinical relevance of this region. METHODS: Microanatomic dissections were performed in 12 formalin-fixed cadaveric specimens. Bony landmarks were examined in 50 dry skulls. Microscopic sections of the region were obtained from cadaveric specimens that were formalin-fixed, decalcified, and processed for histological examination. RESULTS: The foramen lacerum is not a true foramen. No significant structures traverse its fibrocartilage. In this region, the bony and fibrous structures surround the internal carotid artery to form an incomplete canal, which serves as the rostral extension of petrous canal. CONCLUSION: The term foramen lacerum should be restricted to that portion of the cranial base at the confluence of the petrous portion of the temporal, basioccipital, and basisphenoid bones that in vivo is filled with fibrocartilage. The region immediately above the foramen lacerum, occupied by the internal carotid artery and traditionally considered the upper portion of the foramen lacerum, should be considered, anatomically and functionally, to be the rostral extension of the petrous canal. We suggest calling this extension the lacerum portion of the carotid canal.
Although the principalis nucleus (Vp) contains trigeminothalamic and internuclear tract cells, the functional and morphologic differences between the two kinds of neurons have remained unsettled. The present study was aimed to address these problems by using the intracellular horseradish peroxidase injection technique in the cat. Of 20 neurons stained, 7 and 13 were located in the dorsomedial subnucleus (Vpd) and ventrolateral subnucleus (Vpv) of Vp, respectively. The Vpd neurons received input from the intraoral structures only but the Vpv neurons from the intraoral or facial structures. Nineteen neurons could be divided as class I and class II, based on the branching pattern of their stem axons. Class I (eight neurons) had an ascending stem axon without branching. Class II was divided into two subclasses (IIa and IIb). Class IIa (eight neurons) had an ascending stem axon from which branches were given off. Their branches formed a local-circuit restricted to the lower brainstem. Class IIb (three neurons) had a stem axon that formed the local-circuit only. The dendritic morphology was indistinguishable between different classes of neurons and between the subdivisions. Although the dendritic arborization pattern was governed by the location of the somata, it was suggested to be also important elements for determining primary afferent arborizations. In the brainstem nuclei, the jaw-closing motor nucleus received the highest density of projections from class II neurons with the receptive field involving the periodontal ligaments. The present study provides new findings that Vp neurons could be divided into three distinct populations and suggests that each population exerts a distinct function with respect to sensory discrimination, sensorimotor reflexes, or both.