Computed tomographic evaluation of anatomic and pathologic variations in the feline nasal septum and paranasal sinuses

CT anatomy of the head in the Ile de France sheep

Background

CT scan images provide accurate anatomical data from different areas of the body that can be used to diagnose diseases.

Objectives

The present work aimed to describe the normal anatomical structures of the Ile de France sheep head and its morphometric and volumetric properties using computed tomography (CT) and stereological methods.

Methods

Five adult Ile de France sheep heads, which were of mature age (above 10 months), were included in this study. The different cavities of the head, including the nasal cavity, paranasal sinuses, oral cavity, orbital cavity and vestibulocochlear system, were evaluated using CT scans, cross, sagittal and coronal sections.

Results

The mean length, height and width of the skull were 25.3 ± 1.02, 9.8 ± 0.93 and 12.3 ± 0.91 cm, respectively. The results showed that the nasal cavity is divided into three regions. Vestibular, respiratory and olfactory regions. The paranasal sinuses are composed of maxillary, frontal, palatine, sphenoid, lacrimal and ethmoidal that were identified and named in the CT scan images and their corresponding anatomical cross‐sections. The total volume of the head, nasal cavity and oral cavity was estimated to be 2998 ± 202.00, 303 ± 31.33 and 229.3 ± 10.61 cm³, respectively.

Conclusions

The frontal sinus in the Ile de France sheep was limited to the frontal bone without extending into the parietal, temporal, or occipital bones, similar to Saanen goat. This study provided a comprehensive atlas of Ile de France sheep anatomy to internal medicine veterinarians and surgeons.

Applied anatomy of the skull in the Arabian horse: A computed tomographic, cross-sectional, volumetric and morphometric study

This study was conducted to present a comprehensive and integrative computed tomography (CT) – anatomical cross sections atlas of skull, volumetric properties of the paranasal sinuses, and morphometric values for surface cranial nerves in the adult Arabian horse. Ten heads of Arabian horse breed were used. The different structures in the nasal, oral and cranial cavities were determined and labelled in the anatomical sections and their corresponding CT scan images. Three paranasal sinuses namely maxillary, conchofrontal and sphenopalatine sinuses were identified in the CT scan images. The caudal maxillary sinus was the largest paranasal sinus with 131.93 ± 7.67 cm³ volume and the sphenopalatine sinus 13.3 ± 1.2 cm³ volume was the smallest one. The infraorbital foramen was located 4.16 ± 0.18 cm and 4.70 ± 0.35 cm far away from the most rostral point of the facial crest and alveolar root, respectively. The mean distance between the mental foramen and most lateral incisive tooth was 3.12 ± 0.29 cm. These results including present CT scan‐cross‐sectional atlas, paranasal sinuses volume and morphometric properties would be applicable in practice for more precise diagnosis of head lesions and blocking the surface terminal branches of the cranial nerves during surgical operations in this valuable horse's breed.

Anatomical description of the head in Ossimi Sheep: Sectional anatomy and Computed Tomographic approach

The objective of present investigation was to explore the morphology of the head in Ossimi sheep. Here, the nasal, paranasal sinuses, oral, orbital, cranial, auricular and pharyngeal cavities were examined by the computed tomography images interpreted by the anatomical sections. Also, three-dimensional CT of the head was reconstructed. The Ossimi sheep was shown to possess long, double scroll dorsal and ventral nasal conchae that occupy the nasal cavity rostrally, while its caudal part possessed five small ethmoidal triangular nasal projections, the largest one was the middle nasal concha and the others contained the ethmoidal sinus. The dorsal and middle nasal meatuses were narrow and the ventral meatus was wide and lead directly to the choanae. The nasal septum failed to reach the floor at the caudal part of the nasal cavity thus forming a single channel that continued to the nasopharynx. The vomeronasal organ extended throughout the length of the nasal cavity from the incisive duct caudal to the dental pad to the level of the 3^rd upper cheek tooth. The paranasal sinuses identified were the frontal, maxillary, lacrimal, palatine and ethmoidal sinuses. The study recorded the absence of the sphenoid sinus and small palatine sinus in sheep different from that in other ruminants. The obtained results may be useful as a basic anatomical reference for the surgeons and pathologists.

Anatomy of the head in the Saanen goat: a computed tomographic and cross-sectional approach

The present work aimed to investigate the anatomical structures of the Saanen goat head and its volumetric properties using computed tomography (CT) and stereological methods. Eight adult Saanen goat heads were included in this study. The different cavities and structures of the head, including nasal cavity, paranasal sinuses, oral cavity, orbital cavity, and cranial cavity were evaluated using CT scans, cross, sagittal, and coronal sections. The volume of head cavities and structures were estimated using the Cavalieri method. The results showed that the dorsal, middle and nasal ventral concha contained the dorsal, middle and ventral conchal sinuses, respectively. The paranasal sinuses constituted maxillary, frontal, lacrimal, and ethmoidal that were recognized and named in the CT scan images and their corresponding anatomical cross sections. The palatine and sphenoidal sinuses were not seen in the Saanen goat. Total volume of the head, nasal cavity and cranial cavity was estimated to be 1958 ± 205, 825.4 ± 62.6 and 423.6 ± 48.2 cm³, respectively. The frontal sinus was the largest paranasal sinus with a volume of 281.8 ± 16.9 cm³ and the lacrimal sinus with a volume 50.2 ± 6 cm³ was the smallest one. The ventral conchal sinus with a volume of 26.6 ± 4.5 cm³ and middle conchal sinus with a volume of 13.4 ± 2.6 cm³ were largest and smallest nasal sinuses, respectively. These results may be used as a basic data to provide a reference set for volume of the examined head structures resulting in better and more precise diagnosis of any pathological volume alteration.

Canine nasal septum deviation can be a normal variation and correlates with increasing skull indices

Nasal septal deviation has been studied in relation to nasal pathology and mass effect in dogs. The purpose of this retrospective, cross-sectional study was to compare the prevalence of nasal septal deviation in dogs with rhinitis, neoplasia, and those without nasal pathology based on the facial index, skull index, and cranial index. Computed tomographic studies of the nasal cavities of dogs performed over a 5-year period were retrospectively reviewed. This study had 233 dogs meeting the inclusion criteria with 135 dogs with no nasal pathology, 63 dogs with nasal neoplasia, and 35 dogs with rhinitis. The prevalence of nasal septal deviation, the angle, maximum distance, and longitudinal extent of deviation were recorded, as well as measurements to calculate the facial index, cranial index, and skull index. The results showed no difference in the prevalence of nasal septal deviation between dogs with nasal pathology and those without. The mean longitudinal extent of deviation and maximum distance of deviation was statistically greater for those with neoplasia compared to those with rhinitis and without nasal pathology. The longitudinal extent of deviation was inversely proportional to the cranial index, facial index, and skull index. The angle of deviation was directly proportional to the facial index and skull index. In conclusion, nasal septal deviation is an anatomic variant in different breeds of dogs with no predilection based on nasal pathology. Nasal septal deviation should be interpreted cautiously in the assessment of canine nasal disease.

Surgical anatomy of the nasal and paranasal sinuses in Egyptian native sheep (Ovis aries) using computed tomography and cross sectioning

The present work aimed to describe the normal computed tomography (CT) and cross-sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross-sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep.

Computed tomographic anatomy of the nasal cavity, paranasal sinuses and tympanic cavity of the koala

OBJECTIVE

To use cross-sectional imaging (helical computed tomography (CT)) combined with conventional anatomical dissection to define the normal anatomy of the nasal cavity and bony cavitations of the koala skull.

METHODS

Helical CT scans of the heads of nine adult animals were obtained using a multislice scanner acquiring thin slices reconstructed in the transverse, sagittal and dorsal planes. Subsequent anatomical dissection permitted confirmation of correct identification and further delineation of bony and air-filled structures visible in axial and multiplanar reformatted CT images.

RESULTS

The nasal cavity was relatively simple, with little scrolling of nasal conchae, but bony cavitations were complex and extensive. A rostral maxillary recess and ventral conchal, caudal maxillary, frontal and sphenoidal paranasal sinuses were identified and characterised. Extensive temporal bone cavitation was shown to be related to a large epitympanic recess.

CONCLUSIONS

The detailed anatomical data provided are applicable to future functional and comparative anatomical studies, as well as providing a preliminary atlas for clinical investigation of conditions such as cryptococcal rhinosinusitis, a condition more common in the koala than in many other species.

Avaliação radiográfica e tomográfica dos seios nasais de gatos com doenças sinonasais crônicas

Avaliaram-se os seios nasais de 10 gatos mestiços, adultos, acometidos por afecções sinonasais, por meio de exames radiográfico e tomográfico, e descreveram-se as vantagens e desvantagens dos métodos. O grande diferencial do exame de tomografia computadorizada em relação ao exame radiográfico, na avaliação dos seios nasais, foi a detecção de alterações nos seios esfenoides e a maior facilidade em localizar a lateralidade e o grau de envolvimento de alterações dos seios frontais.

Nasal vascular hamartoma in a Domestic Shorthair cat

A nasal mass in a Domestic Shorthair cat was causing facial deformity, sneezing and intermittent epistaxis. Biopsy samples obtained previously had been non-diagnostic. Computed tomography images revealed an irregular, contrast-enhancing mass occupying a large portion of the righthand side of the nasal cavity. Previously described criteria for malignancy were not present. A ventral surgical approach combined with temporary, ipsilateral, common carotid arterial occlusion provided excellent access for debulking the lesion and collecting samples for histopathology. A nasal vascular hamartoma was diagnosed and clinical signs resolved postoperatively. This is the first documentation of this abnormality in the cat. Hamartomatous abnormalities should be included on the list of differential diagnoses for feline nasal mass lesions. The prognosis for hamartomatous lesions postoperatively is good, in keeping with their limited propensity for growth after maturity.

Tomografia computadorizada de feixe cônico na odontologia veterinária: descrição e padronização da técnica

Onze cães e quatro gatos, portadores de alterações buco-dentárias e atendidos no Centro Veterinário do Gama, em Brasília, DF, foram submetidos à tomografia computadorizada de feixe cônico. Os exames foram realizados em um tomógrafo i-CAT, utilizando para aquisição das imagens, altura de seis centímetros, tempo de 40 segundos, 0,2 voxel, 120 kilovolts e 46,72 miliampéres por segundo. O melhor posicionamento dos animais para realização do exame foi definido neste estudo. Esse é um fator fundamental para a realização do exame, que necessitou um protocolo anestésico simples e seguro, em função do tempo mínimo necessário à obtenção das imagens. Várias alterações e enfermidades foram identificadas, com extrema acurácia, credenciando a tomografia computadorizada de feixe cônico como um exame seguro, acessível e exeqüível e que pode ser incorporado à rotina odontológica das clínicas de pequenos animais.