Light microscopy and transmission electron microscopy of cerebellum in embalmed and fresh cadavers.

Objective : The study is to examine the quality of the histological slide of cerebellum in embalmed cadaver when compares with fresh specimen or the standard textbook by using light and transmission electron microscopic studies. Method : The cerebellums were chosen from the embalmed cadavers who donated their bodies to the Department of Anatomy, Faculty of Medicine, Siriraj Hospital, Mahidol University. These cerebellums were prepared by two techniques for light and electron microscopic studies. The visualization of the cerebellar microscopic slides were compared with the fresh specimens or standard textbooks. Results : The cerebellar sections which were obtained from the cadaveric cerebellar embalmed were suitable for making the microscopic slides that can be used for studying histology of the medical students. From light microscopic study, the microscopic structures are as good appearances as in the standard textbooks. Some specimens have better microscopic structural appearances. The fixative formula is suitable for light microscopic study but not suitable for transmissiom electron microscopic study. Conclusion : The microscopic slides from sections of the cerebellums which were obtained from the embalmed cadavers which have been fixed by Siriraj fixative formula and kept in soaking preservative formula for 1 year and have been dissected for studying gross anatomy and neuroanatomy by the medical student under room temperature can be used for microscopic slides that suitable for further teaching or stydying histology.

Sternalis muscle: Anatomical variations in Thais.

Objective: To study and classify the types of the sternalis muscle in Thais, who has lived in Bangkok and the surrounding area, and compare its incidence to that of the other races. Methods: The sternalis muscles were dissected and classified in Thai cadavers. The morphology of each type was shown by photograph. Tables showed numbers and percentage of the muscle in male and female, right and left sides. Results: The study of 126 Thai cadavers, the sternalis muscle was found in 9 cadavers. The incidence was 7.14%. The muscle was divided into 2 types, type A was the bilateral type and type B was the unilateral type. Conclusion: The sternalis muscle was an anatomical variation of the thoracic wall musculature. Its incidence in Thais was 7.14%. The morphology of the muscle was shown and divided into 2 types.

The patterns of the cephalic veins termination.

Objective: To study and classify the types of the terminations of the cephalic veins in the Thais and compare the percent count of each type between male and female, right and left sides. Methods: The ending part of the cephalic veins were dissected and classified in Thai cadavers. Each type was shown by photograph, diagram, number and percent count. Results: The cephalic vein, studied from 208 upper extremities, had three types of termination. Type I, cephalic vein terminated in axillary vein; type II termination was external jugular vein; type III termination was axillary vein and external jugular vein. Conclusion: The termination of cephalic veins were shown and classified into three types and sex had no influence on the patterns of cephalic vein termination.

The mandibular foramen in Thais.

One hundred twenty-two Thai dry mandibles, 67 males and 55 females, were used in measuring the location of the mandibular foramen, and the position was found to be variable. However, the foramen is predominantly located at the anteroposterior diameter, midpoint of the ramous, halfway between the mandibular notch and the lower border of the mandible and two thirds of the way down a line joining the coronoid process to the angle of mandible. The average distance between the mandibular foramen to the sharp external oblique line of the anterior border of the ramous is 1.976 + 0.388 cm., to the round internal oblique line of the anterior border of the ramous 1.433 + 0.670 cm., to the posterior border of the ramous 1.657 + 0.950 cm., to the mandibular notch 2.360 + 0.562 cm., to the standard basal plane 2.287 + 0.397 cm., to the coronoid process 3.872 + 0.616 cm., to the angle of mandible 2.501 + 0.451 and to the posterior surface of third molar 1.993 + 0.379 cm.. The average minimum width of the ramous is 3.437 + 0.401 cm.. The average height of the lingual is 0.0874 + 0.628 cm.. The majority of the mandibular foramen is located below the occlusal surfaces of the lower molars. It is concluded that the marked variability in the position of the mandibular foramen may be responsible for an occasional failure to block the inferior alveolar nerve.

The spondylolysis in Thais.

93 Thai skeletons, 49 male and 44 female, or 465 lumbar vertebrae, 245 males and 220 females, were studied for Spondylolysis. Spondylolysis was found in 11 of 465 lumber vertebrae, 5 male and 6 female. It occurred at the third lumbar vertebra in 1 case, at the fourth lumbar vertebra in 4 cases and at the fifth lumber vertebra in 6 cases. In Thais, spondylolysis has been classified into three patients, the defect occuring bilaterally at the lamina in 9 cases, the defect at the lamina being unilateral in 1 case and the defect at the spine called unfused spine (Spinabifida) in 1 case.

The lumbar vertebrae in Thais.

Four hundred and sixty five lumbar vertebrae of Thais, 245 males and 220 females, were studied for the vertebral foramen, body and inferior Vertebral notches. The antero posterior (A – P) diameter of vertebral foramen and body, the transverse diameter and thickness of the body, the which and depth of inferior vertebral notches were measured. The average values of the vertebral foramen, body and inferior vertebral notches were noted in males and females. The changes of size of the vertebral foramen, body and inferior vertebral notches of the 1st to 5th lumbar vertebrae were noted and a graph was plotted. The graph showed that the A –P diameter of the vertebral foramen decreased from the 1st to the 3rd lumbar vertebral and then increased in diameter in the 4th and 5th lumbar vertebrae; this diameter in males was larger than of the females. The A –P diameter, transverse diameter and thickness of the vertebrae body increased from the 1st to 5th lumbar vertebrae and these values in males were larger than those of the females. The width and depth of the inferior vertebral notches varied. The notches of the 1st lumbar vertebrae in females were wider and deeper than those of the males. In the 2nd lumbar vertebrae, the width of the notches in males and females were similar but the depth in males was deeper than that of the females. In the 3rd lumbar vertebrae, the notches were wider in males but deeper in females. The notches of the 4th lumbar vertebrae in males were wider and deeper than of the females but in the 5th lumbar vertebrae, the width and depth of the notches in females were larger than those of the males.

Variational anatomy of the profunda femoris artery in Thais.

The profunda femoris artery is the great vessel in the thigh. To study the origin and branching variations of this artery, 113 legs were dissected and then the anatomical patterns were classified. The profunda femoris artery originated at an average distance of 4.28 cm. below the inquinal ligament. The most common origin was postero-lateral, occurring in 37.2% of the specimens. The most common origin of the lateral circumflex femoral artery was of the branch from the profunda femoris artery similar to the medial circumflex femoral artery occurring in 77.0% of the specimens. The average number of perforating arteries was three, including the end of the profunda femoris artery.

Pattern of lumbar plexus in Thais.

A Study on the pattern of lumbar plexus was performed in 83 plexus; 42 right and 41 left. The lumbar plexus, generally is formed by the ventral rami of the first lumbar spinal nerve to the fourth lumbar spinal nerve in 68.7 percent. There is no difference in origin of lumbar plexus between right and left side and between sexes. In 75.0 percent of the iliohypogastric nerve is formed by the ventral rami of the first lumbar spinal nerve. In 81.9 percent of the ilio-hypogastric nerve is formed by the ventral rami of the first lumbar spinal nerve. In 74.7 percent of the genitofemoral nerve is formed by the ventral rami of the first and second lumbar spinal nerve. In 71.0 percent of the lateral cutaneous nerve of thigh is formed by the ventral rami of the second and third lumbar spinal nerve. In 89.2 percent of the femoral nerve is formed by the second, third and fourth lumbar spinal nerve. In 90.4 percent of the obturator nerve is formed by the second, third and fourth lumbar spinal nerve.

Jugum cerebellare intersemilunarae in Thais.

The 117 occipital bones of Thais, 67 male, 50 female, were studied for Jugum Cerebellare Intersemilunarea. The origin of the Jugum Cerebellare Intersemilunarea began at the lower border of the groove for transverse sinus near the internal occipital crest. Then it passed downward and laterally ending at the lower-lateral angle of the occipital bone where foramen for the mastoid emissary veins is. Distance between the origins the internal occipital crest and the endings to the lower border of the groove for transverse sinus were measured. The Jugum Cerebellare Intersemilunarea was divided into 9 types; continuous, interrupted, medially and centrally, laterally and centrally, medially and laterally, medial only, lateral only, central only and absent. The types of Jugum Cerebellare Intersemilunarea in Thais were statistically significantly different from of the Europian. In Thais, comparisons between sex and side in both male and female were not found to have any statistically significant difference.