Anterior external arcuate fibers (AEAF) are efferents of the arcuate nuclei, which are located on the ventral surface of pyramids. Several types of fibre bundles superficial to the pyramids have been described in early and mid 20th century.Recently, few of these have been studied in detail. Objective of present study was to observe the morphology of AEAF in the Indian population. Distinct AEAF were noted in 13 out of 50 brain specimens. Based on their relation to olive, AEAF were further classified as supraolivary, preolivary and supraolivary fibers and their prevalence noted as 25%, 15%, and 9% respectively. Supraolivary and preolivary fibers were present together in 9 brainstem sides, while co-presence of preolivary and circumolivary fibers was noted in only 1 side. All three types of fibres were observed together in 5 brainstem sides.When present bilaterally, supraolivary and preolivary fibers were seen in 92.30% and 66.66% of brainstem respectively, while circumolivary fibers were seen bilaterally in 28.57% of brainstem. Supraolivary and circumolivary fibers exhibited variable morphology as single, double and multiple fiber bundles. Morphometric analysis revealed presence of thicker supraolivary fiber bundle on right side, while thicker circumolivary fiber bundles were noted on left side. Present study will add to knowledge of this variable fiber bundle pattern, which has been reported to play an important role in regulation of crucial physiological functions such as breathing and cardiorespiratory mechanisms. These observations open avenues for further research into developmental factors involved in migration of neurons from the rhombic lip.

Anterior external arcuate fibers (AEAF) are efferents of the arcuate nuclei, which are located on the ventral surface of pyramids. Several types of fibre bundles superficial to the pyramids have been described in early and mid 20th century.Recently, few of these have been studied in detail. Objective of present study was to observe the morphology of AEAF in the Indian population. Distinct AEAF were noted in 13 out of 50 brain specimens. Based on their relation to olive, AEAF were further classified as supraolivary, preolivary and supraolivary fibers and their prevalence noted as 25%, 15%, and 9% respectively. Supraolivary and preolivary fibers were present together in 9 brainstem sides, while co-presence of preolivary and circumolivary fibers was noted in only 1 side. All three types of fibres were observed together in 5 brainstem sides.When present bilaterally, supraolivary and preolivary fibers were seen in 92.30% and 66.66% of brainstem respectively, while circumolivary fibers were seen bilaterally in 28.57% of brainstem. Supraolivary and circumolivary fibers exhibited variable morphology as single, double and multiple fiber bundles. Morphometric analysis revealed presence of thicker supraolivary fiber bundle on right side, while thicker circumolivary fiber bundles were noted on left side. Present study will add to knowledge of this variable fiber bundle pattern, which has been reported to play an important role in regulation of crucial physiological functions such as breathing and cardiorespiratory mechanisms. These observations open avenues for further research into developmental factors involved in migration of neurons from the rhombic lip.

Anterior external arcuate fibers (AEAF) are efferents of the arcuate nuclei, which are located on the ventral surface of pyramids. Several types of fibre bundles superficial to the pyramids have been described in early and mid 20th century.Recently, few of these have been studied in detail. Objective of present study was to observe the morphology of AEAF in the Indian population. Distinct AEAF were noted in 13 out of 50 brain specimens. Based on their relation to olive, AEAF were further classified as supraolivary, preolivary and supraolivary fibers and their prevalence noted as 25%, 15%, and 9% respectively. Supraolivary and preolivary fibers were present together in 9 brainstem sides, while co-presence of preolivary and circumolivary fibers was noted in only 1 side. All three types of fibres were observed together in 5 brainstem sides.When present bilaterally, supraolivary and preolivary fibers were seen in 92.30% and 66.66% of brainstem respectively, while circumolivary fibers were seen bilaterally in 28.57% of brainstem. Supraolivary and circumolivary fibers exhibited variable morphology as single, double and multiple fiber bundles. Morphometric analysis revealed presence of thicker supraolivary fiber bundle on right side, while thicker circumolivary fiber bundles were noted on left side. Present study will add to knowledge of this variable fiber bundle pattern, which has been reported to play an important role in regulation of crucial physiological functions such as breathing and cardiorespiratory mechanisms. These observations open avenues for further research into developmental factors involved in migration of neurons from the rhombic lip.

Anterior external arcuate fibers (AEAF) are efferents of the arcuate nuclei, which are located on the ventral surface of pyramids. Several types of fibre bundles superficial to the pyramids have been described in early and mid 20th century.Recently, few of these have been studied in detail. Objective of present study was to observe the morphology of AEAF in the Indian population. Distinct AEAF were noted in 13 out of 50 brain specimens. Based on their relation to olive, AEAF were further classified as supraolivary, preolivary and supraolivary fibers and their prevalence noted as 25%, 15%, and 9% respectively. Supraolivary and preolivary fibers were present together in 9 brainstem sides, while co-presence of preolivary and circumolivary fibers was noted in only 1 side. All three types of fibres were observed together in 5 brainstem sides.When present bilaterally, supraolivary and preolivary fibers were seen in 92.30% and 66.66% of brainstem respectively, while circumolivary fibers were seen bilaterally in 28.57% of brainstem. Supraolivary and circumolivary fibers exhibited variable morphology as single, double and multiple fiber bundles. Morphometric analysis revealed presence of thicker supraolivary fiber bundle on right side, while thicker circumolivary fiber bundles were noted on left side. Present study will add to knowledge of this variable fiber bundle pattern, which has been reported to play an important role in regulation of crucial physiological functions such as breathing and cardiorespiratory mechanisms. These observations open avenues for further research into developmental factors involved in migration of neurons from the rhombic lip.

Anterior external arcuate fibers (AEAF) are efferents of the arcuate nuclei, which are located on the ventral surface of pyramids. Several types of fibre bundles superficial to the pyramids have been described in early and mid 20th century.Recently, few of these have been studied in detail. Objective of present study was to observe the morphology of AEAF in the Indian population. Distinct AEAF were noted in 13 out of 50 brain specimens. Based on their relation to olive, AEAF were further classified as supraolivary, preolivary and supraolivary fibers and their prevalence noted as 25%, 15%, and 9% respectively. Supraolivary and preolivary fibers were present together in 9 brainstem sides, while co-presence of preolivary and circumolivary fibers was noted in only 1 side. All three types of fibres were observed together in 5 brainstem sides.When present bilaterally, supraolivary and preolivary fibers were seen in 92.30% and 66.66% of brainstem respectively, while circumolivary fibers were seen bilaterally in 28.57% of brainstem. Supraolivary and circumolivary fibers exhibited variable morphology as single, double and multiple fiber bundles. Morphometric analysis revealed presence of thicker supraolivary fiber bundle on right side, while thicker circumolivary fiber bundles were noted on left side. Present study will add to knowledge of this variable fiber bundle pattern, which has been reported to play an important role in regulation of crucial physiological functions such as breathing and cardiorespiratory mechanisms. These observations open avenues for further research into developmental factors involved in migration of neurons from the rhombic lip.

The objective of the study was to observe and document the variation on the subject of branches of the median nerve. This report will assist clinicians and surgeons by considering anatomical variation associated with the median nerve in interpreting atypical clinical presentations. The arm and forearm region of a 55 year embalmed male cadaver during educational gross anatomy dissection. We found that an anomalous cutaneous branch arising from the median nerve in the right arm which was passing deep to the tendon of the biceps brachii. Later it enters the cubital fossa and then it is accompanied by the superficial vein of the forearm. The other limb of the cadaver did not show any such variation. No other neural, arterial or muscular variation was observed in either of the limbs. A rare anatomical variation in which the anomalous cutaneous branch arising from the median nerve in the right arm which is later accompanied by a superficial vein in the forearm. Such knowledge is advantageous in nerve grafting and neurophysiological evaluation for diagnosing peripheral neuropathies.
Arm* ; Cadaver ; Extremities ; Forearm ; Humans ; Male ; Median Nerve* ; Peripheral Nervous System Diseases ; Tendons ; Transplants ; Veins

The objective of the study was to observe and document the variation on the subject of branches of the median nerve. This report will assist clinicians and surgeons by considering anatomical variation associated with the median nerve in interpreting atypical clinical presentations. The arm and forearm region of a 55 year embalmed male cadaver during educational gross anatomy dissection. We found that an anomalous cutaneous branch arising from the median nerve in the right arm which was passing deep to the tendon of the biceps brachii. Later it enters the cubital fossa and then it is accompanied by the superficial vein of the forearm. The other limb of the cadaver did not show any such variation. No other neural, arterial or muscular variation was observed in either of the limbs. A rare anatomical variation in which the anomalous cutaneous branch arising from the median nerve in the right arm which is later accompanied by a superficial vein in the forearm. Such knowledge is advantageous in nerve grafting and neurophysiological evaluation for diagnosing peripheral neuropathies.
Arm* ; Cadaver ; Extremities ; Forearm ; Humans ; Male ; Median Nerve* ; Peripheral Nervous System Diseases ; Tendons ; Transplants ; Veins