ABSTRACT
The authors present the case of a 34-year-old man struck over the left mastoid region by a hockey puck, who suffered a fatal rupture of a left vertebral artery berry aneurysm. He became apneic within seconds of the injury and had no brainstem reflex within minutes. The postmortem examination showed massive subarachnoid hemorrhage in the posterior fossa and the remnants of a berry aneurysm near the intradural origin of the left vertebral artery, 11 mm proximal to the posterior inferior cerebellar artery. Rupture of a saccular aneurysm as a result of head trauma is rare. This is the first reported case of a posterior circulation aneurysm rupture as a result of head trauma.
Subject(s)
Aneurysm, Ruptured/diagnosis , Craniocerebral Trauma/complications , Intracranial Aneurysm/diagnosis , Vertebral Artery , Adult , Aneurysm, Ruptured/complications , Athletic Injuries/complications , Fatal Outcome , Hockey , Humans , Intracranial Aneurysm/complications , Male , Radiography , Subarachnoid Hemorrhage/etiology , Subarachnoid Hemorrhage/pathology , Vertebral Artery/diagnostic imaging , Vertebral Artery/pathologyABSTRACT
Extensive longitudinal lesions of the dorsal root entry zone (DREZ) are effective in relieving some chronic deafferentation pain in humans. A deafferentation syndrome follows C5-T2 dorsal root ganglionectomies in rats. The syndrome consists of biting and scratching the completely and partially denervated limb areas, respectively. This study examines the effect of DREZ lesions on the deafferentation syndrome in the rat. Of 37 rats, 24 underwent C5-T2 ganglionectomies only, five received C4-T3 micromechanical DREZ lesions only, and eight underwent ganglionectomies plus simultaneous DREZ lesions. The animals were observed for 45 days post-operatively. Histological analysis of the spinal cord lesions was performed. All rats with ganglionectomies alone exhibited the deafferentation syndrome; however, no rats with DREZ lesions alone showed this feature. Only 25% of rats with combined ganglionectomies and DREZ lesions exhibited the deafferentation syndrome in the first 30 days, whereas 80% of the animals with ganglionectomies only did so. Although 75% of the animals with combined lesions eventually bit the insensitive forepaw, this behavior was significantly attenuated: the day of onset was delayed and the extent of self-mutilation was reduced. Postmortem histological examination of the DREZ lesions indicated a close association between the completeness of the dorsal horn destruction and the reduction or prevention of self-mutilation. These data support the validity of the animal model and also the hypothesis stating that the deafferentation syndrome results from abnormal spontaneous neural activity in the dorsal horn. Moreover, the variability of the histological findings in these experiments stresses the importance of making contiguous and complete dorsal horn lesions in human DREZ surgery.
Subject(s)
Afferent Pathways/physiopathology , Ganglia, Spinal/injuries , Pain/physiopathology , Spinal Nerve Roots/injuries , Analysis of Variance , Animals , Chi-Square Distribution , Denervation , Ganglionectomy , Motor Activity/physiology , Rats , Rats, Sprague-DawleyABSTRACT
New radiofrequency lesion dorsal root entry zone (DREZ) electrodes for relief of facial pain were designed based on a neuroanatomic study in man of the trigeminal nucleus caudalis at the cervicomedullary junction. The human brainstems of 3 normal postmortem specimens were sectioned with measurements and relationships of the trigeminal nucleus caudalis, segmental tracts, spinocerebellar tracts and dorsal columns. Two right-angle DREZ electrodes were made by Radionics for producing DREZ lesions in the trigeminal nucleus caudalis to treat deafferentation facial pain.
