An Electron Microscopic Study of Pathological Changes of the Great Occipital Nerve Following Local Cooling

On electron microscopy the great occipital nerve of the rabbit was studied in its relation to local cooling of the head on the occipital region of the scalp to learn the ill effect of unduly prolonged bed rest using ice pillow following head injury as a part of investigation of chronic post-traumatic headache. After three hours of occipital cooling in the temperature ranging between 2°C. and 5°C. the mylin sheath is swollen, the lamella is torn and vacuoles are formed. The axon becomes atrophic, axon-Schwann interface is enlarged, and spiral invagination of the lamella is common. Endoplasmic reticulums are increased in the axon and mitochondria are swollen and cristae are destroyed. These changes are found in all fibers with no discrimination of their size. After 6 hours of cooling, these changes are brought to the extreme, and most of these changes remain long after cooling is stopped, or they are irreversible. Recovery after three hour cooling is much better. Swelling of the axon and vacuoles in the lamella disappear within two weeks, and axon-Schwann interface returns to their normal relation within two months, although spiral invagination of the lamella may remai

Observation of Microcirculatory Change in the Great Occipital Nerve

One-third of the patients with chronic post-traumatic headache have tenderness of the occipital nerves and, in lesser degree, of the trigeminal nerve. Various factors may contribute to this neuralgic reaction of these nerves which produce headach of extracranial pathology which we have been studying clinically and experimentally. In this paper we report of the observation of changes in microcirculation of the great occipital nerve following occipital cooling and compression. To reverse the impaired microcirculation we adovocate early ambulation and active exercise. Intramuscular injection of adrenaline is expected to produce similar effect on microcirculation which was observed under the perspective microscope

An Electron Microscopic Study of Pathological Changes of the Great Occipital Nerve Following Local Cooling

On electron microscopy the great occipital nerve of the rabbit was studied in its relation to local cooling of the head on the occipital region of the scalp to learn the ill effect of unduly prolonged bed rest using ice pillow following head injury as a part of investigation of chronic post-traumatic headache. After three hours of occipital cooling in the temperature ranging between 2°C. and 5°C. the mylin sheath is swollen, the lamella is torn and vacuoles are formed. The axon becomes atrophic, axon-Schwann interface is enlarged, and spiral invagination of the lamella is common. Endoplasmic reticulums are increased in the axon and mitochondria are swollen and cristae are destroyed. These changes are found in all fibers with no discrimination of their size. After 6 hours of cooling, these changes are brought to the extreme, and most of these changes remain long after cooling is stopped, or they are irreversible. Recovery after three hour cooling is much better. Swelling of the axon and vacuoles in the lamella disappear within two weeks, and axon-Schwann interface returns to their normal relation within two months, although spiral invagination of the lamella may remai