Three-dimensional morphometric and volumetric analysis of maxillary sinuses.

BACKGROUND: The maxillary sinus is a pyramid-shaped cavity with varying shapes, sizes, and capacities. Its dimensions grow gradually and develop until early adulthood. Anatomical knowledge of the maxillary sinus is essential to understanding sinonasal disorders, planning surgical procedures and preventing complications. Awareness of the sinus's proximity to critical structures helps avoid injuries during surgery. The European, Korean, and Sri Lankan population study parameters show varying results and do not necessarily apply to the Indian population. The standard morphometric data of the maxillary sinus is scanty in the Indian population. The study aimed to determine the volume and morphometry of the maxillary sinus along with gender differences in the Eastern population of the Indian. MATERIALS AND METHODS: A retrospective cross-sectional study was conducted using cone beam computed tomography data of maxillary sinuses of 100 normal individuals. The data were analysed after the three-dimensional reconstruction of digital imaging and communications in medicine (DICOM) images with the help of DICOM to print and Geomagic freeform software in the Anatomy department. The different linear morphometric variables and volume of the maxillary sinus were studied. SPSS version 27.0. was utilised for statistical analyses. RESULTS: The mean values of Antero-posterior diameter, Transverse diameter, Craniocaudal diameters, the height of ostium from the floor and volume of the maxillary sinus in males on the right side are 36.61 mm, 20.7 mm, 40.31 mm, 26.02 mm and 16055.24 mm³ and on the left side are 37.17 mm, 20.17 mm, 40.73 mm, 26.91 mm and 15712.66 mm³ whereas in females the values on the right side are 38.10 mm, 21.56 mm, 38.96 mm, 25.81 mm and 14687.78 mm³ and on left side are 38.23 mm, 21.53 mm, 38.48 mm, 25.28 mm and 14203.13 mm3 respectively. The side-to-side parameter differences were non-significant within the male and female groups, respectively. The females had significantly (p < 0.05) larger transverse diameters than males in both the right and left maxillary sinuses. The males tend to have a slightly larger mean craniocaudal diameter than females, but the difference was found statistically significant (p < 0.05) only in the left maxillary sinus. The gender differentiation based on the measured parameters of bilateral maxillary sinus accuracy rate was 89.4% in males and 61.8% in females. CONCLUSIONS: These parameters serve as a standard or reference point, allowing radiologists and surgeons to compare individual patient scans to population averages and aid in better clinical outcomes. The mean values of different parameters of the maxillary sinus may be utilised to differentiate various suspected sinus pathologies, which is helpful for functional endoscopic sinus surgery. Gender differentiation can be done more accurately by forensic experts using Maxillary sinus transverse diameter bilaterally, followed by craniocaudal diameter of the left side sinus for predicting the gender of an unknown maxilla.

Hiding Beaver Tail Liver: A Rare Anatomical Variant of the Liver.

Accessory liver lobes are indeed morphological variations of the liver, representing additional lobes or smaller structures connected to the main liver mass. Beaver tail liver is a rare anatomic variation where the left lobe of the liver encroaches to enclose the spleen. These variants, often found by chance in patients, can create challenges in accurately distinguishing between the liver and spleen in imaging, potentially leading to misdiagnosis as splenic trauma or a subcapsular hematoma. While conducting routine dissections of the abdomen region, a variation in the size, position, and anatomical connections of the liver was noticed in a female cadaver of age 45 years. The left lobe of the liver was elongated more towards the left lateral side with some angulated narrowing after extending across the midline, encroaching the left upper quadrant of the abdomen, reaching in between the stomach and the visceral surface of the spleen, above the hilum of the spleen. The narrow end of the left lobe of the liver, placed in between the stomach and spleen, is named the hiding beaver tail liver. This variation differs from the typical beaver tail liver as well as the "kissing sign" of the liver and spleen. Unfamiliarity with such an anomaly of the liver may lead radiologists and clinicians to identify a normal anatomical variant as a pathological condition mistakenly or could confuse radiologists with fluid collections that often suggest trauma, potentially leading to fatal outcomes during invasive abdominal procedures.

Morphometric analysis of sacral corridor in the upper three sacral segments to prevent neurovascular injury.

Although studies of the sacral corridor dimension have been reported in the European population, little attention has been paid to this issue in the Asian population. The purpose of the study is to estimate the safe dimension of the corridor to avoid neurovascular damage during the fixation of the sacral fracture. The study aimed to examine the cephalocaudal (vertical) and the anteroposterior diameter of the bony passage in the upper three sacral segments. The study further examines the effect of age and sex on corridor dimensions at different sacral levels. Three-dimensionally reconstructed sacra from computed tomography of normal subjects were included in the study. Cephalocaudal and anteroposterior diameters were measured in coronal and axial sections using Geomagic Freeform Plus software. Anteroposterior diameter of the sacral corridor at the first, second, and third sacral segments are significantly higher in males (P=0.013, 0.0011, and <0.0001, respectively). The length of the sacrum also revealed sexual dimorphism (P<0.00016). The anteroposterior diameter of the second sacral segment (ap-S2c) correlated moderately with the first sacral anteroposterior diameter (ap-S1c) (R=0.519, P<0.001). The ap-S2c exhibited a moderate correlation to the third sacral segment (ap-S3c) (R=0.677, P<0.001). The sacral corridor at the level of S1 has the largest cephalocaudal (18.25 mm) and anteroposterior diameter (17.11 mm). Placement of the screw in the first sacral corridor may avoid damage to the neurovascular bundle during the fixation of the sacral fracture.

An evaluation of mandibular canal variations: a systematic review and meta-analysis.

The inferior alveolar nerve and vessels are carried via the mandibular canal, which extends bilaterally from the inferior alveolar foramen to the mental foramen. Bifid and trifid mandibular canals result from abnormal fusions of nerve canals. The purpose of this study was to provide an up-to-date and comprehensive analysis of the prevalence of mandibular canal variations among healthy adults, and to identify any potential ethnic, sex, or laterality predilections. The prevalence of the bifid mandibular canal was 18.87% and that of the trifid canal 1.3%. Unilateral variants were three times commoner than bilateral. Each mandibular half had four canals emanating from separate openings on the lingual surface of the mandibular ramus. Retromolar and forward canals were the predominant subtypes, followed by dental; buccolingual were the least frequent. The mean length and diameter of the bifid mandibular canal were 13.62 mm and 1.63 mm, respectively. The possibility of a bifid mandibular canal is a crucial consideration in dental medicine. Because anatomical variations of the mandibular canal are fairly common, awareness of them is essential for anatomy teachers and for surgeons who operate in the oromaxillofacial region.