Research Article

A study on the impressions of middle meningeal vessels in temporal and parietal K. Ashwini, Ganesh Lakshmanan, M. S. Thenmozhi*

ABSTRACT

Aim: This study aims to study the impressions of middle meningeal vessels in temporal and . Introduction: The middle meningeal artery (MMA) is the first part and the third part of the maxillary artery which supplies to the meninges. It has a very complex branching which gives rise to many anatomical structures and is useful for studies. It has a very great clinical significance in dealing with fractures, epidural hematomas, and bypass procedures. Hence, we decided to investigate its anatomical organization. Materials and Methods: A total of 50 human without any gross breakage were taken and examined using a Vernier caliper. The length and pattern of anterior and the posterior branches of MMA were measured and recorded. Results: These impressions were found to vary from to skull. Compared to the right and left temporal and parietal bone, it is found that the left side of both the has a larger diameter than the right side due to the increased functioning of the left part of the brain. Conclusion: These results will be useful to increase the detailed knowledge of the important atrial segment of the skull which has a very important clinical significance in the medical field. KEY WORDS: , parietal bone, middle meningeal vessels, impressions

INTRODUCTION contacts with the temporal bone () and ().[3] It A human skull is bony and has various anatomical also has two surfaces: Outer one is smooth and has structures in it. The inner surface has numerous parietal tuberosity. Posteriorly, a is impressions underlying the soft tissues. The impressions also present. Both the right and left parietal bones of middle meningeal vessels (MMV) are found to be meet in the . The inner concave surface [1] formed in the inner surface of the skull/cranium. has certain grooves for the MMV. These impressions are due to the atrial pressure that causes the bones to Roof of the skull and the sides of the neurocranium recede. are formed by the parietal bone[2] which is present in between the occipital and frontal bones. It is concave The temporal bone is bilateral and attributes to the and convex internally and externally. Moreover, lower lateral parts of the neurocranium. It is one this is the only largest bone in the neurocranium. of the most important calvarial skull base bones. This is irregularly quadrilateral and possesses four Its lower portion with the mandible forming angles: The anterosuperior angle is frontal angle. The the temporomandibular . The temporal bone is anteroinferior angle is the sphenoidal angle and is the made up of five parts: Squamous, tympanic, mastoid, sharpest angles of all. The posterosuperior angle is petrous, and styloid. It also forms the middle and the occipital angle. The posteroinferior angle is the inner ear. mastoid angle. It consists of four borders: Anteriorly, it borders the (); posteriorly The middle meningeal artery (MMA) is the third by the (); and laterally branch of the first part of maxillary artery. This is the most common source of extradural hemorrhage.[4] Access this article online It arises just behind the condylar process and enters the neurocranium through . MMA Website: jprsolutions.info ISSN: 0975-7619 runs forward and laterally and grooves the squamous

Department of Anatomy, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India,

*Corresponding author: Mrs. M. S. Thenmozhi, Department of Anatomy, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai - 600 077, Tamil Nadu, India. Phone: +91-9884138681. E-mail: [email protected]

Received on: 04-02-2019; Revised on: 14-03-2019; Accepted on: 17-04-2019

1830 Drug Invention Today | Vol 11 • Issue 8 • 2019 K. Ashwini, et al. temporal bone and divides into parietal and frontal posterior branches in parietal bone was determined branches.[5,6] The frontal branch is larger and forward [Figures 2,3]. and lateral and end in the greater wing of sphenoid. It also runs obliquely up and down, parallel, and a little RESULTS front in central sulcus of cerebral hemisphere. The parietal branch runs backward over or near the superior As per our observations, there is a significant temporal sulcus of the cerebrum and 4 cm above the difference between the anterior and posterior branches level of . It ends in its posteroinferior of MMA in the right and left parietal bone. The data angle and divides into branches. were expressed as mean ± standard deviation (SD). The diameter of MMA ranged from 0.69 to 2.31 in After the MMA passes through the foramen spinosum, the anterior branch of the right parietal bone with an at this point, it gives off the ganglionic branches to average diameter of 1.30 ± 0.05 mm. The diameter of trigeminal ganglion, a petrosal branch to the hiatus for MMA ranged from 0.6 to 3.67 in the anterior branch the greater petrosal nerve, a superior tympanic branch of the left parietal bone with an average diameter of to the tensor tympani, and temporal branches to the 1.46 ± 0.09 mm. The diameter of MMA ranged from and makes impression in the temporal 0.18 to 1.53 in the posterior branch of the right parietal bone.[7,8] bone with an average diameter of 0.84 ± 0.03 mm. The diameter of MMA ranged from 0.27 to 2.12 in MATERIALS AND METHODS the posterior branch of the left parietal bone with an average diameter of 0.81 ± 0.05 mm. A total of 50 human parietal and temporal bones of unknown sex and without any gross breakage are The diameter of MMA in the right and left temporal obtained from the Department of Anatomy, Saveetha bone also showed a significant difference. The Dental College and Hospitals, Chennai. They were values ranged from 0.61 to 1.76 in the right temporal subjected to morphometric analysis and evaluated. bone with an average diameter of 1.25 ± 0.05 mm. Using a Vernier caliper, the diameter of impressions of MMA in temporal bone is evaluated [Figure 1]. In the same way, the diameter of MMA in anterior and

Figure 1: Impressions of middle meningeal artery in temporal bone Figure 3: Right parietal bone with MMA impressions

Figure 4: The mean diameter between the right and left anterior Figure 2: Left parietal bone with MMA impressions branches of parietal bone. Values are expressed as a mean ± SD

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diameters of both the bones, the left side has a larger diameter compared to the right because there is an increased in activity of the brain in the left cerebrum than the right cerebrum which requires a lot of nutrients along with associated tissues.[9]

Compared to the right temporal bone as in Figure 6, the left temporal bone is larger in diameter of MMA and has a more prominent impression. Despite the clinical importance, MMA has shown a greater variation in their impressions.[10,11]

CONCLUSION Figure 5: The mean diameter between the right and left posterior branches of parietal bone. Values are expressed as This study reveals the important aspects of the a mean ± SD impressions of MMV on temporal and parietal bone. Through our observations, it would increase the detailed observations of arteries through clinical implications. It keenly provides the bilateral arrangement and impressions of MMA inside the neurocranium.[9,12]

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