Morphologie und ontogenetische Veränderungen der Suturen des Gesichtsschädels beim Pferd: Computertomographische und histologische Untersuchungen
Buch in deiner Nähe kaufen
Beschreibung
Diseases of the head in adult horses, which primarily and/or secondarily involve the sutures, are described as inflammation of the sutures (suturitis) and as peri- and endosteal bony proliferation. Current publications suggest that these diseases have more clinical relevance than previously assumed. On one hand, they are only described in adult horses but on the other hand, only open sutures are affected by these conditions.
Furthermore, morphological descriptions of the sutures in the equine facial skull are missing. These appear to be the sutures that are particularly affected. Overall, 52 CT-datasets from skulls from horses at the age of under one year to 30 years were available for investigation. The program Amira 6.2.® was used to control the sampling site and to reconstruct CT-cross-sectional images. The transverse cross-sectional images of the CT-datasets were evaluated and analyzed by an inexperienced and an experienced examiner using a commercially available computed tomography program. Following the CT examination, six skulls were processed histologically and examined. The internasal suture, the left and right fronto-nasal suture, the left and right lacrimo-maxillary suture, and the left and right zygomatico-maxillary suture were evaluated.
In total, 135 open, 28 partially open and 201 closed sutures were analyzed computer-tomographically. Overall, the result of the histological examination was a total number of 55 open sutures, classified as syndesmosis, and 346 closed sutures, categorized as synostosis. The sutures were described histomorphologically: the bone margins showed a rim of cells forming a transition to the connective tissue fibers. Numerous spindle-shaped fibrocytes, which were situated either centrally or marginally, as well as sporadic blood vessels, were embedded inside the connective tissue. The course of the sutures was linear, meander-shaped, heart-shaped or circular. Specifically, a direct contact between the sutures and the cartilaginous septum nasi, the mucosa of the sinus conchae dorsalis as well as the nasal mucosa were detected. Closed sutures in CT displayed no band of connective tissue histologically. Partially closed sutures in CT however showed a band of connective tissue between the bone margins histologically. More open sutures were found in the histological examination than by CT. Morphological results were analyzed with regard to different age categories (young, < 5 years; adult, < 20 years; geriatric, < 31 years). The internasal suture was predominantly open (94.74%, 63.16%) in young (n= 19) and adult horses (n=19), but mainly partially open (80%) in geriatric horses (n=10). The zygomatico-maxillary suture as well as the lacrimo-maxillary suture were already closed (21.05%) in some young horses. In contrast, open sutures were found only in a few geriatric horses (10%). While over half (57.89%) of the fronto-nasal suture was already completely closed in young horses, the number of closed sutures increased with increasing age of the horses, so that the sutures were already closed in geriatric horses.
The results of this study confirm an age-dependent closure of sutures. From an etiopathological standpoint, suturitis and suture exostosis can only occur in open sutures as inflammatory changes of suture-own connective tissue.
This current study describes morphological and histological characteristics of the sutures of the equine facial skull for the first time. Thus, forming a basis for further, clinical studies.
Autor*in
Sabine Kern
Themen in »Morphologie und ontogenetische Veränderungen der Suturen des Gesichtsschädels beim Pferd: Computertomographische und histologische Untersuchungen«
Doktorarbeit Knochenbau Tiermedizin