scholarly journals Morphometrical Study of the European Shorthair Cat Skull Using Computed Tomography

2021 ◽  
Vol 8 (8) ◽  
pp. 161
Author(s):  
Joana Ramos ◽  
Inês Viegas ◽  
Hugo Pereira ◽  
João Filipe Requicha
Keyword(s):  
Computed Tomography ◽  
Foramen Magnum ◽  
Domestic Cat ◽  
Linear Measurements ◽  
Internal Length ◽  
Tomographic Images ◽  
Computed Tomographic ◽  
Cranial Index ◽  
Nasal Length ◽  
Morphometrical Study

This study aimed to perform a morphometric analysis of the skull of the European shorthair cat by using computed tomographic images. Thirty-seven computed tomography (CT) studies of healthy cats’ heads were used for linear measurements and index calculations of the skull and cranium. The following values were determined: skull length = 8.94 ± 0.45 cm, cranial length = 8.21 ± 0.42 cm, nasal length = 0.73 ± 0.17 cm, cranial width = 4.28 ± 0.26 cm, cranial index = 52.18 ± 3.75%, internal height of cranium = 2.88 ± 0.29 cm, external height of cranium = 3.35 ± 0.12 cm, internal length of the cranium = 5.53 ± 0.28 cm, external length of the cranium = 6.32 ± 0.28 cm, internal cranium index = 45.62 ± 4.77%, external cranium index = 53.06 ± 2.07%, internal cranium and skull index = 61.93 ± 2.38%, external cranium and skull index = 70.70 ± 1.72%, width of the foramen magnum = 1.34 ± 0.07 cm, height of the foramen magnum = 1.01 ± 0.09 cm, and foramen magnum index = 75.37 ± 5.76%. It was also found that the population was homogeneous, with the exception of nasal length (NL), and that there was a sexual dimorphism present, with males exhibiting higher dimensions. This work contributed to characterizing the morphometry of the cranium and skull of the domestic cat, a knowledge of utmost importance for the diagnosis and treatment of conditions affecting this complex anatomical region.

Three-dimensional Computed Tomographic Cranial Base Measurements for Improvement of Surgical Approaches to the Petrous Carotid Artery and Apex Regions

Neurosurgery ◽  
2001 ◽  
Vol 49 (2) ◽  
pp. 342-353 ◽  
Author(s):  
Alan T. Villavicencio ◽  
Jean-Christophe Leveque ◽  
Ketan R. Bulsara ◽  
Allan H. Friedman ◽  
Linda Gray
Keyword(s):  
Computed Tomography ◽  
Carotid Artery ◽  
Three Dimensional ◽  
Internal Auditory Canal ◽  
Cranial Base ◽  
Petrous Apex ◽  
Surgical Approaches ◽  
Tomographic Images ◽  
Computed Tomographic ◽  
Preoperative Information

Abstract OBJECTIVE The bony and vascular anatomic features in the region of the petrous apex can vary significantly. These variations affect the operative view obtained via extended subtemporal or anterior transpetrosal approaches to cranial base lesions for individual patients. The goal of this study was to evaluate three-dimensional computed tomography as a means of obtaining detailed preoperative anatomic information regarding bony and vascular landmarks and spatial relationships in the region of the petrous carotid artery and petrous apex. METHODS We radiographically studied 15 patients (30 sides), using 0.8- to 1-mm-thick, reconstructed, computed tomographic images. Special attention was given to the course of the petrous carotid artery. RESULTS The petrous carotid artery was located lateral to the trigeminal impression. The size of the petrous apex medial to the horizontal petrous carotid artery was observed to be variable. The width of bone from the trigeminal impression to the wall of the internal auditory canal averaged 9.6 mm (range, 5.2–16.1 mm). A variable amount of bone overlying the internal auditory canal (4.5 mm) was also present. Multiple other relationships among key landmarks were quantified. CONCLUSION There is significant variability in the anatomic features of the petrous apex among patients. For each patient, detailed preoperative information regarding the amount of bone to be removed during a cranial base procedure can be obtained using three-dimensional computed tomography. This information may be critical for determination of the amount of extra exposure that can be achieved via an anterior petrosectomy for each patient.

Computed tomography assisted determination of optimal insertion points and bone corridors for transverse implant placement in the feline tarsus and metatarsus

2014 ◽  
Vol 27 (06) ◽  
pp. 441-446 ◽  
Author(s):  
M. Grapperon-Mathis ◽  
B. Bouvy ◽  
M. Benlloch-Gonzalez
Keyword(s):  
Computed Tomography ◽  
Body Weight ◽  
Significant Positive Correlation ◽  
Metatarsal Bone ◽  
Tarsal Bone ◽  
Tomographic Images ◽  
Medial Surface ◽  
Computed Tomographic ◽  
Implant Placement

SummaryObjective: Describe optimal corridors for mediolateral or lateromedial implant placement in the feline tarsus and base of the metatarsus.Methods: Computed tomographic images of 20 cadaveric tarsi were used to define optimal talocalcaneal, centroquartal, distal tarsal, and metatarsal corridors characterized by medial and lateral insertion points (IP), mean height, width, length and optimal dorsomedial-plantarolateral implantation angle (OIA).Results: Talocalcaneal level: The IP were at the head of the talus and plantar to the peroneal tubercle of the calcaneus and OIA was 22.7° ± 0.3. Centroquartal level: The IP were at the centre of the medial surface of the central tarsal bone and dorsoproximal to the tuberosity of the fourth tarsal bone and OIA was 5.9° ± 0.06. Distal tarsal level: The IP were at the centre of the medial surface of the tarsal bone II and dorsodistal to the tuberosity of the fourth tarsal bone and OIA was 5.4° ± 0.14. Metatarsal level: The IP were at the dorsomedial surface of the proximal end of the metatarsal bone II and at the dorsolateral surface of metatarsal bone V and OIA was 0.5° ± 0.06. Significant positive correlation was found between body weight and the length of each corridor.Clinical significance: Most of the corridors obtained in this study had a diameter between 1.5 mm and 2 mm with a length of 15 mm to 18 mm, which stresses the importance of their accurate placement.

scholarly journals Evaluation of mandibular volume classified by vertical skeletal dimensions with cone-beam computed tomography

2016 ◽  
Vol 86 (6) ◽  
pp. 949-954 ◽  
Author(s):  
Takatoshi Nakawaki ◽  
Tetsutaro Yamaguchi ◽  
Daisuke Tomita ◽  
Yu Hikita ◽  
Mohamed Adel ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Three Dimensional ◽  
Cone Beam ◽  
Class Iii ◽  
Tomographic Images ◽  
Computed Tomographic ◽  
Significant Difference ◽  
Detailed Assessment ◽  
Lateral Cephalometry

ABSTRACT Objective: To investigate the relationship between anteroposterior and vertical differences in maxillofacial morphology and mandibular volume. Materials and Methods: Subjects comprised 213 Japanese adults (84 males and 129 females) who were divided into three groups based on mandibular basal arch (ANB) and Wits, measured in a cephalometric analysis: Class I (−1° ≤ ANB < 4°,−1 mm ≤ Wits < 0 mm), Class II (ANB ≥ 4°, Wits ≥ 0), and Class III (ANB <−1°, Wits <−1 mm). Subjects were also divided into three groups based on the mandibular plane angle (Mp), as follows: hypodivergent (Mp < 23°), normodivergent (Mp  =  23–30°), and hyperdivergent (Mp > 30°) groups. Mandibular volume was measured from cone-beam computed tomographic images that were analyzed using Analyze™ image processing software and compared among the three groups in each classification. Results: No significant differences were noted in mandibular volume among Classes I, II, and III. An inverse relationship was found between mandibular volume and Mp, and a significant difference was noted in mandibular volume between the hypodivergent and hyperdivergent groups. Conclusions: In addition to two-dimensional analysis, such as lateral cephalometry, three-dimensional information such as volume, provided by cone-beam computed tomography, contributes to a more detailed assessment of maxillofacial morphology.

Computed tomography of ununited anconeal process in the dog

2012 ◽  
Vol 25 (06) ◽  
pp. 498-505 ◽  
Author(s):  
J. J. Labruyère ◽  
J. F. Bardet ◽  
E. G. Gasch
Keyword(s):  
Computed Tomography ◽  
Coronoid Process ◽  
Tomographic Images ◽  
Computed Tomographic ◽  
Elbow Dysplasia ◽  
Preoperative Ct ◽  
Sclerotic Lesions ◽  
Grade 3 ◽  
Humeral Condyle ◽  
Ct Features

SummaryObjective: The purpose of this study was to describe computed tomography (CT) features of the ununited anconeal process and relate them with the following elbow dysplasia signs: medial coronoid disease, medial humeral condyle changes, osteoarthritis (OA), and radioulnar incongruence.Methods: Computed tomographic images of dogs older than six months with an ununited anconeal process were evaluated (n = 13). Ununited anconeal process features were described as being complete or incomplete, and the degree of displacement, volume, and presence of cysts and sclerosis were also evaluated. Medial coronoid disease was defined as an irregular medial coronoid process shape, presence of sclerosis and fragmentation. Medial humeral condyle changes were defined as subchondral bone flattening, lucencies, and sclerosis. Osteoarthritis was graded depending on the osteophytes size. Radioulnar incongruence was measured on a sagittal view at the base of the medial coronoid process.Results: Eleven elbows had a complete and two had an incomplete ununited anconeal process. All ununited anconeal processes had cystic and sclerotic lesions. Seven ununited anconeal processes were displaced and six were non-displaced. Mean ununited anconeal process volume was 1.35 cm3 (0.61 cm3 – 2.08 cm3). Twelve elbows had signs of medial coronoid disease (4 of them with a fragmented medial coronoid process), and one elbow did not show any evidence of medial coronoid disease. Ten elbows had medial humeral condyle changes. One elbow had grade 1 OA, seven elbows had grade 2, and five elbows grade 3. All elbows had radioulnar incongruence: three elbows had a negative and 10 elbows had a positive radioulnar incongruence. Mean radioulnar incongruence was 1.49 mm (0.63 mm – 2.61 mm). Computed tomographic findings were similar in the majority of the elbows studied: complete ununited anconeal processes with signs of medial coronoid disease, positive radioulnar incongruence, high grade of OA, sclerotic medial humeral condyle changes, and large ununited anconeal process volumes.Clinical significance: Incomplete small ununited anconeal process volumes could be associated with a lower incidence of medial coronoid disease or medial humeral condyle changes. We recommend performing preoperative CT of elbows with an ununited anconeal process to evaluate concurrent lesions.

Quantitative Analysis of the Transcondylar Approach to the Foramen Magnum

Neurosurgery ◽  
2001 ◽  
Vol 49 (4) ◽  
pp. 934-943 ◽  
Author(s):  
John E. Wanebo ◽  
Michael R. Chicoine
Keyword(s):  
Computed Tomography ◽  
Quantitative Analysis ◽  
Ct Images ◽  
Foramen Magnum ◽  
Ct Scans ◽  
Computed Tomographic ◽  
Suboccipital Craniotomy ◽  
Before And After ◽  
Skull Measurements ◽  
C 50

Abstract OBJECTIVE Condylar resection with suboccipital craniotomy increases foramen magnum exposure, but guidelines for when this is necessary are not defined. Cadaveric and computed tomography evaluations were completed to guide decision-making regarding the use and extent of condylar resection. METHODS Quantitative analysis of foramen magnum surgical exposures was performed on 32 skulls (64 sides) and 6 cadaveric dissections (12 sides). Computed tomographic (CT) scans were performed on cadaveric heads before and after condylar resections. Digitized images of dry skulls and CT images of cadaver heads were quantitatively analyzed. Predissection CT measurements of cadaveric heads guided extent of condylar resections, and resection accuracy was assessed with postdissection CT scans. RESULTS Skull measurements (means in parentheses) included the foramen magnum area (7.8 cm2), length (3.6 cm), width (3.1 cm), anteroposterior condylar length (2.3 cm), and axial condylar length (2.5 cm). Mean widths of potential surgical exposures for skulls were obtained for A) suboccipital craniotomy (2.3 cm), B) with 25% (2.6 cm), and C) 50% condylar resection (3.0 cm). Mean angles of exposure were as follows: A, 38.4 degrees; B, 49.1 degrees; and C, 54.3 degrees. CT scans of cadaveric heads before and after dissections yielded measurements of exposure equivalent to measurements found on the dry skulls. CONCLUSION On average, lateral exposure increases by 3 mm (13%) and 7 mm (30%) for 25 and 50% condylar resection, respectively, compared with suboccipital craniotomy alone. Angles of exposure increase by 10.7 degrees (28%) and 15.9 degrees (41%). Measurements of CT images can be used preoperatively to help analyze the need for condylar resection and intraoperatively to guide the extent of condylar resection.

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