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Kodo Kodama

Publications and source records attributed to Kodo Kodama.

15 recordsLinked to original sources

A case of nonrotation of the midgut with a middle mesenteric artery.

In 2002, we came across a very rare case of nonrotation of the midgut with a middle mesenteric artery (MM) (tentative name). It was found in a 73-year-old Japanese female cadaver donated for student dissection at Kumamoto University. In this case, the small intestine occupied the right half of the abdominal cavity and the large intestine occupied the left half. The caecum was situated on the anterior inferior part of the abdominal cavity near the midline. The duodenum (Du) was fused to the posterior abdominal wall. The small intestine except the Du and the ascending colon were suspended from the posterior abdominal wall by the mesentery, but the remainder of the colon was fused to the left posterior abdominal wall. In addition, an anomalous branch arose from the abdominal aorta between the superior and inferior mesenteric arteries (SM and IM) in this case. It chiefly supplied the ascending and the transverse colons and anastomosed with the SM and IM, respectively, through the marginal arteries. It is very rare that these anomalies appear simultaneously in one body. In this case, it is difficult to declare that the existence of the MM directly caused the nonrotation of the midgut, but it is reasonable to suppose some kind of relation between them.

Aged↗

The inferior supernumerary renal arteries: a classification into three types.

Among cases that had multiple renal arteries on one side, an inferior supernumerary renal artery was found in 24/270 cases (ca. 9%) on the right and in 19/270 cases (ca. 7%) on the left, together with the usual renal artery. We have noticed that there are correlations between their levels of origin from the aorta and their positional relation to the ureter and the inferior vena cava (IVC). An inferior supernumerary renal artery (InfRA) of lower origin passes in front of the IVC and behind the ureter. An InfRA of middle origin passes in front of both the IVC and the ureter. An InfRA of upper origin passes behind the IVC and in front of the ureter or renal pelvis. In addition there was a tendency for the lower origin type to have an ureteric branch, while the middle and upper origin types had a gonadal branch. These findings suggest that different derivations lead to the inferior supernumerary renal arteries.

Aged↗

A middle meningeal artery which arises from the internal carotid artery in which the first branchial artery participates.

A middle meningeal artery arising from the internal carotid artery was found in the right half of the head of an 85-year-old male cadaver during student dissection practice. It arose from the lateral aspect of the internal carotid artery in the carotid canal, arrived at the foramen lacerum after running forward. It then ran backward under the trigeminal ganglion and took the usual course after passing its posterior margin. On one hand, the maxillary artery did not issue the middle meningeal artery, gave off only a small twig supplying the lateral pterygoid muscle at the corresponding position. It was corroborated by the fact that the foramen spinosum was absent in this example. During usual development, the middle meningeal artery primarily springs from the supraorbital branch of the stapedial artery that arises from the dorsal part of the second branchial artery. Later, by the formation of the external carotid artery connecting with the common trunk of the infraorbital and mandibular branches (maxillomandibular division) of the stapedial artery and by the atrophy of the proximal part of it, the middle meningeal artery is finally supplied by the external carotid artery. But in this example, it is supposed that the middle meningeal artery arose from a more distal position of the internal carotid artery owing to the persistence of the anastomosis between the dorsal part of the first branchial artery and the supraorbital branch and the interruption of the connection between the supraorbital branch and maxillomandibular division of the stapedial artery.

Aged, 80 and over↗

The deep axillary artery.

An aberrant axillary artery running deep to the brachial plexus during its course was observed. The brachial plexus in this case was formed by the fourth cervical nerve to the first thoracic nerve and the radial nerve received a small nerve bundle (accessory radial nerve root) from the posterior aspect of the lower trunk. The axillary artery passed between the lateral and the medial cords of the brachial plexus, the same as for an ordinary axillary artery. In addition, it passed between their posterior divisions, forming the posterior cord, and further ran between the radial nerve root and the accessory radial nerve root from deep to superficial. This axillary artery was recognized as the deep axillary artery, the same as the axillary artery we have reported previously. It was thought that the branches to the subscapularis and serratus anterior muscles, nutrient branch to the radial nerve root and the subscapular artery played important roles in its formation.

Aged, 80 and over↗

Double innervation of the anterior belly of the digastric muscle.

We came across a very rare case in which the anterior belly of the digastric muscle was innervated by the twigs of the facial nerve in addition to those of the mylohyoid nerve. The anomaly was discovered in the cadaver of an 84-year-old Japanese male bequeathed for a training seminar in gross anatomy at Kumamoto University in 2003. One twig issued from the marginal mandibular branch of the facial nerve and entered the central region of the anterior belly of the digastric muscle on the lower surface. The other twig issued from the stylohyoid branch of the facial nerve, descended along the lateral margin of the stylohyoid muscle and entered the anterior belly of the digastric muscle on the lower surface near the intermediate tendon. The twig from the marginal mandibular branch was distributed to the shallow (lower) and central region near the medial margin of the anterior belly. The twig from the stylohyoid branch was distributed to the shallow and lateral region of the anterior belly. These two twigs communicated with the mylohyoid nerve at several peripheral parts. Textbooks on general anatomy make mention of only one nerve, the mylohyoid, supplying the anterior belly of the digastric muscle. However, the present case manifests that the anterior belly receiving twigs from the mylohyoid and facial nerves is formed with the second brachial component as well as the first.

Aged, 80 and over↗

An aberrant axillary artery penetrating the origin of the radial nerve from deep to superficial.

An aberrant axillary artery that penetrated the radial nerve from deep to superficial during its course, was observed. The brachial plexus in the present case was classified as the Adachi's C-type brachial plexus. Further, an accessory radial root existed, which was a nerve bundle branching from the deep aspect of the inferior trunk and communicating with the radial root from the posterior cord to form the radial nerve. The axillary artery went on along the lower border of the brachial plexus and passed between the radial root and the accessory radial root from deep to superficial at its third section. As the axillary artery penetrated the origin of the radial nerve from deep to superficial, it was judged to reach deep under the posterior cord, hence deeper than the brachial plexus.

Aged↗

Scalenus muscles in macaque monkeys.

The attachment and innervation of the scalenus muscles in both sides of two Japanese monkeys and a rhesus monkey were observed to discuss their morphological significance while comparing their findings in humans. The scalenus ventralis muscle in macaques had almost the same attachments as the scalenus anterior muscle in humans and was innervated by the cervical nerve branches, which were lower in spinal segment than in humans and had a close relationship with the branches to the intertransversus ventralis muscles. Furthermore, the scalenus ventralis muscle was penetrated by the phrenic nerve in all cases observed. The posterior part of the scalenus muscle in macaques (the scalenus dorsalis muscle) was divided into short (the scalenus dorsalis brevis) and long (the scalenus dorsalis longus) parts according to their attachments. The former was attached to the transverse processes of the lowest two cervical vertebrae and the first rib, whereas the latter was attached to the 3rd-5th ribs. It is notable that the scalenus dorsalis muscles in macaques were innervated by branches from the long thoracic nerve in addition to direct branches from the cervical nerve roots. In addition, the scalenus dorsalis longus was supplied by twigs from the lateral cutaneous branches of the 2nd and 3rd intercostal nerves. This indicates that the scalenus dorsalis muscles contain a muscular component derived from the upper limb girdle musculature, unlike the human scalenus muscles, which have been considered to belong to the cervical trunk muscles.

Animals↗

An anatomical study of the partial anomalous pulmonary venous return with special references to the bronchial vein.

Two examples of partial anomalous drainage of the pulmonary vein were detected at dissection. The first case was found in a 70-year-old female Japanese. An aberrant vein, approximately 6 mm in diameter, that derived from the upper lobe of the right lung was observed to drain into the superior vena cava at a point just below the entrance of the azygos vein. The other veins from the right lung gathered into two pulmonary veins and returned into the left atrium as usual. In the second case, which was found in an 80-year-old female Japanese, a connecting vein, approximately 8 mm in diameter, was found between the left superior pulmonary vein and the left brachiocephalic vein. In this case, although the direction of the blood flow within the connecting vein was not certain, it is probable that the blood passed from the pulmonary vein into the brachiocephalic vein, judging from the increase in the width of the latter vein. No other anomalies were found in the cardiovascular systems. At the occurrence of the anomalous drainage of the pulmonary veins in both cases, we suspected the role of the bronchial vein to be a communicating and boundary vein between the pulmonary and systemic circulations. The developmental background of these anomalies is also considered.

Aged↗

Derivation of the anterior belly of the digastric muscle receiving twigs from the mylohyoid and facial nerves.

The anterior belly of the digastric muscle is usually supplied by the mylohyoid nerve, and in general anatomy textbooks, the anterior belly is invariably described as receiving no other nerve except the mylohyoid nerve. In fact, however, it is sometimes supplied by a branch of the facial nerve in addition to the mylohyoid nerve. Such cases were found in 8 bodies or 9 head sides among 539 bodies or 1078 head sides of Japanese subjects. Those nine cases were investigated in detail and it was clarified that they had the following three characteristics in common: (1) the twig originating from the facial nerve appears as the twig of the stylohyoid branch in most cases, (2) the twig from the facial nerve enters the anterior belly on its lower (shallow) surface and the twig of the mylohyoid nerve on its upper (deep) surface, (3) the twig of the mylohyoid nerve is distributed to the deep region and the twig of the stylohyoid branch is distributed to the shallow region of the anterior belly. From these results, it was concluded that the anterior belly, receiving the twigs of the mylohyoid and facial nerves, had been formed by secondarily combining the most ventral and rostral part of the primordium of the stylohyoid muscle in the second branchial arch with the caudal part of the primordium of the anterior belly in the first branchial arch.

Autopsy↗

Aberrant axillary artery descending deep beneath the brachial plexus.

An aberrant axillary artery that descended deep beneath the brachial plexus during its course was observed. The artery passed between the lateral and medial cords, as would an ordinary axillary artery, but further passed between the posterior divisions forming the posterior cord. The axillary artery turned medially to emerge from the lower border of the medial cord and finally ran as an ordinary artery. The aberrant axillary artery is judged to reach deeper to the brachial plexus, because it penetrated the posterior division of the brachial plexus from superficial to deep. It is possible to account for the formation of this artery as one of the combinations of the ordinary axillary artery and its branches, with the positional relationships between the brachial plexus.

Aged↗

Superficial brachial artery crossing over the ulnar and median nerves from posterior to anterior: embryological significance.

A rare variation of the superficial brachial artery was found in the right arm of an 82-year-old male cadaver in student dissection practice. In this case, the axillary artery passed normally between the medial and lateral roots of the median nerve and then bifurcated into a large superficial brachial artery and the deep brachial artery (A. brachialis profunda). The superficial brachial artery passed medially to the ulnar nerve and then crossed over to take a lateral course to the median nerve at the midpoint of the upper arm. It finally divided into the radial and ulnar arteries at the cubital fossa. The deep brachial artery terminated as the inferior ulnar collateral artery. These findings indicate that the present variant was a well-developed medial type of the superficial brachial artery that gave off the ulnar and radial arteries. The anatomical and embryological significance of the findings are discussed.

Aged↗

Rare variation of the arm artery: coexistence with the superficial brachial and superficial subscapular arteries in the absence of the normal brachial artery.

A rare variation in the arterial pattern was found in the right arm of an 87-year-old male cadaver in a student dissection practice. In this case, the superficial brachial and superficial subscapular arteries coexisted in the absence of the normal brachial artery (A. brachialis profunda). After branching off a large-sized superficial subscapular artery, the axillary artery did not penetrate the brachial plexus and gave rise to a superficial brachial artery, which arose from the axillary artery at the point between the ansa pectoralis and ansa mediana, and descended ventral to the median nerve branching off the profunda brachii and superior and inferior ulnar collateral arteries. The superficial brachial artery finally divided into the radial and ulnar arteries in the cubital fossa. The superficial subscapular artery passed inferior and dorsal to the medial cord of the brachial plexus, giving off the lateral thoracic artery, and then branched off into the thoracodorsal, circumflex scapular and posterior circumflex humeral arteries. Thus the main nerves of the brachial plexus were sandwiched between the superficial brachial artery and the superficial subscapular artery system. The morphological and clinical significance of this variant are discussed.

Aged↗

Anomalous lumbrical muscles arising from the deep surface of flexor digitorum superficialis muscles in man.

During anatomy practice in 1999 at Kumamoto University School of Medicine, the anomalous lumbrical muscles originating in the forearm were observed in both arms of a cadaver. These muscles, originating from the intermediate tendon of the deep layer of the flexor digitorum superficialis for the index finger (FDS-II), passed through the carpal tunnel to join the insertion of the first lumbrical muscle, and formed a muscle belly near the origin in the left and at the insertion in the right. The left anomalous muscle was innervated by a branch of the median nerve just proximal to the carpal tunnel. The right one received a twig from the nerve to the first lumbrical muscle. Tracing the nerve fibers by peeling off the epi- and perineurium clarified that the nerve fibers supplying the left anomalous muscle formed a common bundle with the fibers to the first lumbrical muscle. Therefore, these anomalous muscles are considered to be the accessory lumbrical muscles arising from the forearm. The three accessory lumbricalis, including one case reported by Yamada (1986), received branches which had slightly different origins from proximally (nerve to the distal belly of FDS-II) to distally (nerve to the first lumbricalis). Accordingly the position of the muscle belly shifted distally. The occurrence of these unusual accessory lumbrical muscles indicates that the distal belly of FDS-III and the first lumbricalis are derived from a common muscle origin and presents an important clue to the phylogenetic origin of the flexor digitorum superficialis.

Aged↗

A histologic study of extralobar pulmonary sequestration and its anomalous artery as a clue to its development.

In 1997, an anomalous small mass of soft tissue was found in the left thoracic cavity of a Japanese male cadaver during student dissection practice. It was linked only by branches from the thoracic aorta, hemiazygos vein and greater splanchnic nerve, with no connection to the normal lung by vessels or airway. Examination of cut sections clarified that this anomalous small tissue mass was an extralobar pulmonary sequestration (EPS). Many cases of pulmonary sequestration have been reported from the clinical aspect, but there are few from a purely anatomical viewpoint. In the present case, detailed gross anatomical and histologic observations clarified that the anomalous artery supplying the sequestration resembled an elastic artery. In view of the findings of other reports, the anomalous arteries are divided into two types, the elastic type such as the pulmonary artery and the muscular type such as the bronchial artery. So it is thought that the histologic observation of an anomalous artery in comparison with normal pulmonary and bronchial arteries may offer an important clue to consider in elucidating the origin and development of pulmonary sequestration.

Aged↗

Morphological study of a horseshoe kidney with special reference to the vascular system.

This is a morphological study on an autopsy case of horseshoe kidney found in a 79-year-old-female cadaver. This kidney consisted of two distinct renal masses that were connected at their lower poles by a parenchymal isthmus that was located in the front of the abdominal aorta at the level of the fourth lumbar vertebra. The kidney was supplied by four arteries arising from the abdominal aorta. The distribution of intrarenal arteries showed that the nature of segmental arteries in the present case was basically the same as in the normal kidney, except that the isthmus had its own blood supply from the artery directly arising from the aorta approximately 28 mm below the origin of the inferior mesenteric artery. Venous drainage from the kidney, including the isthmus, was taken by three veins that opened independently into the inferior vena cava. No congenital malformations were found in other organs. We discuss the anatomical and embryological significance of this anomaly and its associated vascular system.

Aged↗