Sudden death following periorbital pellet injury

PURPOSE

To report an uneventful sudden death because of a periorbital pellet injury.

METHOD

Review of autopsy findings.

RESULTS

A 20-year-old hunter was shot accidentally during hunting. At autopsy, the body showed no significant injuries or deformity except for the pellet injuries and ecchymosis on the medial side of the left lower eyelid. Skull roentgenography located a pellet in the base of the cranium. Upon craniotomy, the cause of death was diagnosed as subarachnoidal haemorrhage due to incomplete basilar artery injury. The pellet entered through the medial cantus, passed through the inferior orbital fissure than the sphenooccipital junction and basilar artery and lodged in the pons.

CONCLUSION

A-high index of suspicion is required in order to detect an intracranial extension in periorbital injuries.

[The implications of cervical spine degenerative and traumatic diseases in the pathogenesis of cervical vertigo and hearing loss]

AIM

Cervical spine together with vestibular system,visual system and proprioceptive afferents plays an important role in mentaining balance. Spine damage causes distortions in transmitting informations to the brain,favoring vertigo.

MATERIAL AND METHOD

The authors point out the occurrence of positional vertigo on 23 patients (20 patients with cervical spondylosis and 3 patients with cervical spine injury) due to blood flow disturbance through vertebral artery.

RESULTS

The mechano-receptors located in intervertebral disks and cervical spine muscles are activated by column movement. Changes of blood flow in the vertebral and basilar arteries are showed up by cervical X-Rays, intracranial Doppler ultrasound or angio-MRI, an audiogram marking out the degree of hearing loss or tinnitus occurence. ENT complex treatment outcomes are analyzed and balneo-physio-therapy performed in order to improve vertigo and hearing loss.

CONCLUSIONS

Stress beside muscle overload and cervical spine injures causes alteration in the ear blood-flow circulation that leads to hearing loss, vertigo and tinnitus. It emphasies the need for collaboration between balneologist and ENT specialist in solving balance and hearing disorders with cervicogenic cause.

Traumatic entrapment of the vertebrobasilar junction due to a longitudinal clival fracture: a case report

Vertebrobasilar junction entrapment due to a clivus fracture is a rare clinical observation. The present case report describes a 54-yr-old man who sustained a major craniofacial injury. The patient displayed a stuporous mental state (Glasgow Coma Scale [GCS]=8) and left hemiparesis (Grade 3). The initial computed tomography (CT) scan revealed a right subdural hemorrhage in the frontotemporal region, with a midline shift and longitudinal clival fracture. A decompressive craniectomy with removal of the hematoma was performed. Two days after surgery, a follow-up CT scan showed cerebellar and brain stem infarction, and a CT angiogram revealed occlusion of the left vertebral artery and entrapment of vertebrobasilar junction by the clival fracture. A decompressive suboccipital craniectomy was performed and the patient gradually recovered. This appears to be a rare case of traumatic vertebrobasilar junction entrapment due to a longitudinal clival fracture, including a cerebellar infarction caused by a left vertebral artery occlusion. A literature review is provided.

Longitudinal clivus fracture associated with trapped basilar artery: unusual survival with good neurological recovery

A 46-year-old motorcyclist sustained severe cranio-facial fractures from a fall at 60 km/h. He gradually developed a left hemiparesis and diplopia but retained a GCS of 15. CT head scan revealed a longitudinal clivus fracture. MRA of intracranial vessels identified a trapped basilar artery. The patient made an excellent recovery with residual left abducens palsy on follow-up at 10 weeks. Such recovery with minimal residual deficit in the context of this injury has not previously been reported. Reported cases to date are reviewed and causative mechanisms discussed.

Fibromuscular dysplasia of the basilar artery: an unusual case with medico-legal implications

A 28-year-old male car driver was reported to suddenly loose the control over his vehicle, to hit the right and middle crash barrier, and to be unconscious as the car came to a halt in a position at right angles to the road. The car was hit in its left side by an automobile with high velocity, and the 28-year-old driver died. Examination of the brain revealed a massive isolated basal subarachnoid hemorrhage and a complete tearing of the basilar artery. A macroscopically detectable aneurysm was not found. However, histological examination of the large arteries at the base of the brain showed (i) fibromuscular dysplasia (FMD) mostly involving the basilar artery (ii) with a ruptured micro-aneurysm in its upper third part. The observations of the eye witnesses that the driver initially lost control over his car were judged in favour of the accused to be due to that rupture of the micro-aneurysm, while complete transverse tearing of the basilar artery occurred during the car crash due to hyperextension and rotation of his neck. Intracranial FMD is a rare cause in the differential diagnosis of isolated basal subarachnoid hemorrhage. The medico-legal implications of this entity are described in the presented case.

Cerebellar haemorrhage after non-traumatic evacuation of supratentorial chronic subdural haematoma: report of two cases

Cerebellar haemorrhage is an unusual complication of supratentorial neurosurgery. Several causative pre-operative factors and medical risk factors may predispose patients to cerebellar haemorrhage, however its etiology remains still unclear. Only two case reports have previously described the occurrence of cerebellar haemorrhage after subdural haematoma evacuation by burr-hole trepanation. We present two patients with this rare postoperative complication of minor supratentorial neurosurgery and possible underlying pathophysiological mechanisms are discussed. Our two cases support the post- rather than per-operative pathogenetic hypothesis. Although the complication is associated with a significant morbidity and mortality, most cases follow a benign course.

Vascular Injury and Transsphenoidal Surgery

Vascular complications can and do arise from transsphenoidal surgery and, when they occur, they have a high incidence of mortality and serious morbidity. The anatomic substrate for such complications is discussed, along with technical aspects of surgery and other methods for the avoidance of vascular complications.

Single or Multiple Small Subarachnoid Hemorrhages by Puncturing a Small Branch of the Rat Basilar Artery Causes Chronic Cerebral Vasospasm

OBJECTIVE

This study looked at the effects of single and multiple small subarachnoid hemorrhage (SAH) caused by puncturing a small branch of the basilar artery in rats.

METHODS

Rats were subjected to single SAH (n = 21), multiple SAH (n = 21), sham operation (n = 21), or no procedures (control group, n = 7). SAH was induced in rats by transclival puncture of a small branch of the basilar artery. In the multiple-SAH hemorrhage groups, three small hemorrhages were produced in the same artery at three different times (initial and 24 and 48 h). In the single-SAH groups, one small hemorrhage was produced. Measurements of local cerebral blood flow (LCBF) were made at the initial SAH procedure and at three different time points. Seven animals from each general grouping were killed on Days 4, 10, and 14 (after LCBF was measured). Three different levels of the basilar artery were examined in each animal. Luminal area and arterial wall thickness were measured, and the findings were compared with control and corresponding sham group findings.

RESULTS

LCBF dropped dramatically (by 40%) immediately after SAH and reached levels near baseline within 15 minutes (n = 42) (P < 0.001). LCBF continued to drop after initial SAH and reached the lowest level on Day 10 (P < 0.001) or Day 14 (P < 0.05). Significant luminal narrowing (P < 0.01) and thickening of the arterial wall (P < 0.01) were observed in both groups.

CONCLUSION

Single or multiple small SAHs produced by puncturing the basilar artery in the rat cause similar acute and chronic cerebral vasospasm.

Medico-legal Aspects of Traumatic Injury of the Vertebrobasilar Artery

Based on our experiences with medico-legal autopsies, we analyzed traumatic injury of the vertebrobasilar artery (VBA) in traffic accident victims. VBA rupture occurred in six cases with traumatic medullary lesions, but in none with cervical cord injury. A relatively small external force applied to the head or neck can induce isolated traumatic subarachnoid hemorrhage (SAH), which accounts for approximately 11% of fatal head injuries. We examined the relationship between site of impact and site of vascular injury in 16 cases of isolated traumatic SAH. The results showed that the vertebral artery (VA) on the side of impact tended to be longitudinally injured in victims experiencing an external force equivalent to that of a fist punch to the head or face. There was no clear relationship between the site of impact and the site of vascular injury in victims who had sustained an external force greater than that of a fist punch. However, our results suggest that an external force causing rotation of the head was likely to cause tearing of the artery. In cases in which an external force equivalent to that of a fist punch was applied to the head, a raised blood alcohol level was a significant risk factor for artery rupture. Furthermore, a difference in the diameters of the left and right VAs was a risk factor for artery rupture. To determine why the VA, the most frequent site of arterial dissection, is also frequently the site of injury, we histologically examined normal and dissected VBAs. We also discuss medico-legal issues of the causal relationship between external force applied and rupture or dissection of the VA.

Ten years of experience with pediatric neuroendoscopic third ventriculostomy: features and perioperative complications of 210 cases

Obstructive hydrocephalus remains a problem, and improvements in fiberoptic technology have promoted interest in neuroendoscopic ventriculostomy (NTV) as an alternative to standard cerebrospinal fluid shunts. The present study assessed 210 pediatric NTVs performed between 1994 and 2004 in patients aged 2 months to 10 years. Five children needed same-session ventriculoperitoneal shunting due to insufficient bypass of the obstruction. The other 205 procedures were technically successful, but 7 patients needed early-postoperative shunting and 10 required late shunting. During NTV, 86 (40.1%) of the patients developed arrhythmia. One patient arrested during balloon dilatation, but normal rhythm returned after deflation and epinephrine/atropine therapy, with no resultant morbidity. Twenty-six (10.2%) patients developed tachycardia (without hypertension) followed by bradycardia, and 6 children (2.8%) developed hypertension. In 1 case (0.5%), a branch of the basilar artery ruptured during fenestration and the hemorrhage was controlled after craniotomy. In 5 cases, mild venous bleeding was controlled by irrigation. The early complications included transient ocular divergence (n = 1), anisocoria (n = 2), and hyponatremia (n = 5). Five children were diagnosed with temporary diabetes insipidus in the late-postoperative period. The neuroendoscopic approach is considered safe for treating hydrocephalus in children, but complications can be severe or lethal and the anesthesiologist must respond accordingly.

Medicolegal diagnostic value and clinical significance of traumatic incomplete tears of the basilar artery

Ruptures of arteries of the vertebrobasilary system are relatively frequent in medicolegal practice, and their origin may be both natural and violent. Tears that affects the whole thickness of the basilar artery cause subarachnoid hemorrhage (SAH), with an often rapid fatal outcome. 1-3 However, in some situations, arterial tears may be incomplete, involving the intima or both the intima and the media, but with preserved adventitia. 1, 4 Although such incomplete tears are not the source of immediate subarachnoid bleeding, their presence may be important from both a medicolegal and a clinical point of view. The aim of this article is to point out the significance of incomplete tears of basilar artery as a possible diagnostic sign of traumatic origin of SAH as well as a certain mechanism of injury, which involves forcible hyperextension and rotational movements of the head. The authors also describe their method of performing longitudinal section of the basilar artery, both at autopsy and for histologic examination, which is convenient for identifying multiple transversal incomplete tears of this blood vessel. The article is based on the analysis of three cases from the autopsy material of the Institute of Forensic Medicine in Belgrade.

Endoscopic reverse third ventriculostomy via the cisterna magna: anatomical study and proposal of a novel procedure

Basilar artery injury has been known as a potential lethal complication of endoscopic third ventriculostomy. In order to avoid this complication, endoscopic reverse third ventriculostomy via a trans-cisterna-magna route was studied. A cadaveric study was performed for navigation of a flexible endoscope through the cisterna magna. Three fresh, unfixed cadavers were used for this endoscopic navigation. In the prone position, a small vertical paramedian skin incision is made at the mid-portion of the posterior neck. An 11-mm threaded plastic tube is inserted towards the posterior arch of the atlas. After a partial hemilaminectomy of the atlas, a flexible endoscope is introduced into the cisterna magna and is navigated cephalad along the vertebrobasilar artery to the inferior aspect of the floor of the third ventricle. Through the working channel of a fiberscope, third ventriculostomy is performed in a reverse direction. Additional detailed anatomy was studied in fixed cadaveric head specimens with a rigid rod-lens endoscope for anatomic orientation. A novel technique of a trans-cisterna-magna reverse third ventriculostomy was studied in cadaveric specimens. This technique may avoid basilar artery injury which occurs occasionally during conventional third ventriculostomy.

Vertebrobasilar dissection: a possible role of whiplash injury in its pathogenesis

We reviewed 29 patients with vertebrobasilar dissections (VBD) to investigate the correlation between minor trauma and VBD and the clinical features of this trauma-related condition. Mean age was 43 years, with a male predominance (male/female ratio was 25/4). Seventeen patients presented with subarachnoid hemorrhage (SAH), and 12 with ischemic symptoms. Two patients presenting with ischemia had extracranial VBD (V3 segment). Angiographically, aneurysmal dilatation was observed in most SAH patients (13 patients) in contrast to narrowing or occlusion in most ischemic patients (10 patients). Among the 12 SAH patients treated with coil embolization or conservatively, five died, whereas all ischemic patients recovered well with anticoagulation and/or antiplatelet therapy. Seven patients had received minor or trivial head/cervical trauma, due to whiplash injury, minor fall, or during exercise, which were identified to precede with the lapse of some time (a few minutes or days) the onset of symptoms. All of these patients presented with ischemic symptoms, and they were younger than the other ischemic or SAH patients. The site of vertebral artery dissection was intracranial in four cases, extracranial in one case, and combined in two cases at the level of the V3 segment and the origin of the posterior inferior cerebellar artery. However, no SAH occurred. These clinicopathological findings, i.e. ischemia and angiographic narrowing/occlusion, suggest that dissections were subintimal. Therefore, it is believed that this minor or trivial trauma may primarily cause subintimal dissection with luminal compromise, leading to ischemic symptoms, rather than subadventitial or transmural dissection with aneurysmal dilatation, leading to SAH. This lesion may also occur in younger patients with a favorable outcome. Careful note should be made of patient for the early recognition of this disorder.

Endovascular management of a basilar artery false aneurysm secondary to endoscopic third ventriculostomy: case report

OBJECTIVE AND IMPORTANCE

Third ventriculostomy for the management of noncommunicating hydrocephalus is a commonly performed procedure with a 5% complication rate. One of the known complications is basilar artery injury.

CLINICAL PRESENTATION

We report a case of basilar artery injury, intraventricular hemorrhage, and false aneurysm formation in a 30-month-old boy after third ventricle floor fenestration.

INTERVENTION

The false aneurysm was managed with endovascular trapping by use of Guglielmi detachable coils without morbidity.

CONCLUSION

Endovascular therapy can be used successfully to manage vascular injury after third ventriculostomy.

Traumatic basilar artery occlusion caused by a fracture of the clivus--case report

A 56-year-old man presented with a rare traumatic basilar artery occlusion caused by a fracture of the clivus. He fell from the height of 2 meters and immediately fell into a coma. Head computed tomography (CT) revealed an open depressed fracture, an acute epidural hematoma 1 cm thick in the left middle frontal fossa, and a longitudinal fracture of the clivus. Emergency removal of the hematoma was performed with cranioplasty. Head CT 8 hours 50 minutes after injury showed infarctions in the brain stem, cerebellum, and occipital lobes. Cerebral angiography revealed occlusion of the basilar artery in the middle part of the clivus. The patient died after 3 days. Autopsy revealed that the basilar artery was trapped in the clivus fracture site. Vertebrobasilar artery occlusion due to trapping in a clivus fracture has a very poor prognosis. Diagnosis is difficult and generally only confirmed at autopsy. Cerebral angiography is recommended in a patient in a deep coma without massive brain contusion at the early stage of head injury to identify the possibility of vertebrobasilar artery occlusion in a clivus fracture.

A lateral mass fracture of C1 associated with left vertebral artery and mid-basilar artery occlusion

Extreme acceleration and deceleration forces as well as axial loading are exerted at the occipito-cervical junction of drivers involved in high-velocity motor vehicle accidents, especially with fastened seatbelts. Injury at this level, usually lethal, can go unrecognized despite modern emergency management of the unconscious patient. A precise neurologic and radiographic workup of damage to this area is often not possible or overlooked in the initial phase of such severe trauma. We describe a patient with multiple injuries who sustained a left vertebral artery occlusion associated with a left-sided lateral mass fracture of C1 and a basilar artery occlusion resulting in a locked-in syndrome after an automobile accident.

Traumatic rupture of the basilar artery: report of two cases and review of the literature

Two cases of traumatic rupture of the basilar artery are reported. In the first case, severe basal subarachnoid hemorrhage (SAH) due to a complete transverse tear of the basilar artery was observed in a 53-year-old restrained male driver who was involved in a head-on collision while intoxicated and drowsy. He lost consciousness shortly after the accident and was admitted to hospital in cardiopulmonary arrest. Intensive resuscitative therapies produced cardiac response, but he died 50 minutes after the accident. The ethanol concentration in his blood and urine was 0.35 and 0.55 mg/ml, respectively. In the second case, SAH due to a similar tear of the basilar artery was observed in a 47-year-old man who received several fist blows to the face while intoxicated. He suddenly lost consciousness after the final blow and was admitted to hospital in cardiopulmonary arrest. Intensive resuscitative therapies produced cardiac response, but he died 6 hours after the event. In these cases, the mechanism of the traumatic rupture of the basilar artery is thought to be overstretching due to hyperextension of the head, and intoxication, drowsiness, or both may have interfered with the decedents' ability to protect themselves; thus, the hyperextension of the head may have been rather forceful.

Traumatic basilar artery dissection in a child: need for anticoagulation?

Dissection of a cerebral blood vessel is a rare complication of acute neurotrauma with a high incidence of morbidity and mortality. We report on a case of a pediatric patient with severe neurological symptoms in whom angiography showed evidence of a basilar artery dissection. The patient was heparinized and recovered uneventfully.

Risk factors and precipitating neck movements causing vertebrobasilar artery dissection after cervical trauma and spinal manipulation

STUDY DESIGN

Potential precipitating events and risk factors for vertebrobasilar artery dissection were reviewed in an analysis of the English language literature published before 1993.

OBJECTIVES

To assess the literature pertaining to precipitating neck movements and risk factors for vertebrobasilar artery dissection in an attempt to determine whether the incidence of these complications can be minimized.

SUMMARY OF BACKGROUND DATA

Vertebrobasilar artery dissection and occlusion leading to brain stem and cerebellar ischemia and infarction are rare but often devastating complications of cervical, manipulation and neck trauma. Although various investigators have suggested potential risk factors and precipitating events, the basis for these suggestions remains unclear.

METHODS

A detailed search of the literature using three computerized bibliographic databases was performed to identify English language articles from 1966 to 1993. Literature before 1966 was identified through a hand search of Index Medicus. References of articles obtained by database search were reviewed to identify additional relevant articles. Data presented in all articles meeting the inclusion criteria were summarized.

RESULTS

The 367 case reports included in this study describe 160 cases of spontaneous onset, 115 cases of onset after spinal manipulation, 58 cases associated with trivial trauma, and 37 cases caused by major trauma (3 cases were classified in two categories). The nature of the precipitating trauma, neck movement, or type of manipulation that was performed was poorly defined in the literature, and it was not possible to identify a specific neck movement or trauma that would be considered the offending activity in the majority of cases. There were 208 (57%) men and 158 (43%) women (gender data not reported in one case) with an average age of 39.3 +/- 12.9 years. There was an overall prevalence of 13.4% hypertension, 6.5% migraines, 18% use of oral contraception (percent of female patients), and 4.9% smoking. In only isolated cases was specific vascular disease such as fibromuscular hyperplasia noted.

CONCLUSIONS

The literature does not assist in the identification of the offending mechanical trauma, neck movement, or type of manipulation precipitating vertebrobasilar artery dissection or the identification of the patient at risk. Thus, given the current status of the literature, it is impossible to advise patients or physicians about how to avoid vertebrobasilar artery dissection when considering cervical manipulation or about specific sports or exercises that result in neck movement or trauma.

Basilar artery occlusion due to spontaneous basilar artery dissection in a child

Basilar artery occlusion (BAO) causing brainstem infarction occurred in a 7-year-old boy without any basic disorders. A diagnosis of BAO due to basilar artery dissection (BAD) was suspected at angiography, and this was confirmed by gadolinium-enhanced magnetic resonance imaging (MRI). These investigations clearly showed all the typical diagnostic signs such as a pseudolumen, double lumen and intimal flap, and a pseudolumen in resolution. The spontaneous healing of the dissection was clearly demonstrated during 10 months of follow-up. We stress that BAD can occur in young children and that combined diagnosis with gadolinium-enhanced MRI and angiography is conclusive for diagnosis of dissecting aneurysms. Wider use of these combined diagnostic methods will allow the detection of less severe basilar artery dissection, thus extending the spectrum of presentation and prognosis.

Use of a microvascular Doppler probe to avoid basilar artery injury during endoscopic third ventriculostomy. Technical note

Basilar artery (BA) injury has been reported in a number of cases as a major complication of third ventriculostomy for hydrocephalus. This report describes the deployment of a pulsed-wave microvascular Doppler probe through the endoscope to locate the BA complex and subsequently to select a safe zone for perforation of the third ventricular floor. This procedure is quick and easily learned, and it is hoped that it can decrease the risk of vascular injury during third ventriculostomy.

Cerebellar mutism after basilar artery occlusion--case report

A 30-year-old female became comatose due to embolic occlusion of the basilar artery, caused by surgical injury to the origin of the vertebral artery during removal of a neurinoma in the upper thoracic paravertebral region. The basilar artery occlusion was treated by local fibrinolysis through a microcatheter. Two weeks later she recovered her consciousness but suffered mutism. Her speech disturbance was characterized by severe ataxic dysarthria known as "cerebellar mutism" but without cranial nerve paresis. The mutism gradually improved during the following 3 months. This is case of cerebellar mutism was apparently due to ischemic stroke. Disturbance by hypoperfusion of the cerebellum and brain stem may have been involved in the pathogenesis of cerebellar mutism.

Endovascular coil occlusion of a traumatic basilar-cavernous fistula: technical report

OBJECTIVE AND IMPORTANCE

We describe an unusual case of an 8-year-old male patient presenting with a traumatic basilar artery aneurysm associated with a basilar-cavernous fistula.

CLINICAL PRESENTATION

The fistula occurred as the result of an accident involving a vehicle and a pedestrian. The patient originally presented in a coma and with a dense left hemiparesis.

INTERVENTION

The traumatic basilar aneurysm and basilar-cavernous fistula were successfully occluded by endovascular coil embolization in two sessions. By 6 months after injury, the patient had made an excellent neurological recovery, requiring only a left leg brace for walking.

CONCLUSION

Endovascular coil embolization provided an effective treatment option in the case of this complex and unusual arteriovenous fistula. We discuss the radiological and clinical features of related traumatic neurovascular lesions.

Traumatic basilar artery dissection causing locked-in syndrome

We report on a patient with traumatic dissection limited to the basilar artery causing a locked-in syndrome. Magnetic resonance imaging (MRI) showed infarction of the basis pontis and a high signal intensity ring surrounding the central lumen of the basilar artery. Vertebral angiography revealed a double lumen within the basilar artery, consistent with a dissection. MRI and angiography are complementary to each other, and we consider both to be necessary for accurate diagnosis. Because MRI is less invasive than angiography, MR examinations should be performed before angiography for screening.

Spontaneous thrombosis of a basilar artery traumatic aneurysm in a child

Traumatic aneurysms are rare and occur most commonly in young adults; however, the relative frequency in the pediatric population is high, owing to the low prevalence of congenital saccular aneurysms in children. Traumatic aneurysms typically involve the anterior circulation, and spontaneous thrombosis is uncommon; hence, surgery is usually necessary. We present a case of a posttraumatic aneurysm in a child that occurred after a fall from a large height and that spontaneously thrombosed.

Basilar artery perforation as a complication of endoscopic third ventriculostomy

The morbidity and mortality associated with third ventriculostomy has decreased significantly over the past 75 years since its introduction by Walter Dandy. Now more commonly performed using an endoscopic method, the significant morbidity of third ventriculostomy has dropped to approximately 5%; essentially that associated with ventriculoscopy in general. However, the possible complication of massive subarachnoid hemorrhage resulting from perforation of the basilar artery or its branches in the course of fenestration of the floor of the third ventricle has only recently been reported. In our case, subsequent to a vascular injury, a pseudoaneurysm developed at the site of vascular perforation, which was then appropriately controlled. The patient has since made a full recovery. Our goal is to remind the endoscopist of this unusual complication and to discuss our management strategies.

Traumatic basilar aneurysm after endoscopic third ventriculostomy: case report

OBJECTIVE AND IMPORTANCE

This case illustrates that although endoscopic third ventriculostomy for patients with aqueductal stenosis is successful and minimally invasive, it can have severe, life-threatening complications.

CLINICAL PRESENTATION

A 3-year-old girl presented with hydrocephalus and aqueductal stenosis. She underwent endoscopic third ventriculostomy with laser fenestration of the third ventricular floor. During the procedure, she developed a severe intraventricular hemorrhage that required prolonged external ventricular drainage and ultimately ventriculoperitoneal shunting. Despite having a negative angiogram after the procedure, she presented 1 month later with a subarachnoid hemorrhage and a traumatic basilar tip aneurysm.

INTERVENTION

The patient underwent a right subtemporal approach with clip ligation of the aneurysm and subsequently had a good recovery.

CONCLUSION

Hemorrhagic complications after endoscopic third ventriculostomy are rare. The formation of a traumatic basilar tip aneurysm after this procedure has not been reported in the literature. Laser fenestration of the third ventricular floor may increase the risk of this event.

Autopsy findings of fatal complication of posterior cerebral circulation angioplasty

Percutaneous transluminal angioplasty is a technique widely used to treat stenotic atherosclerotic lesions of the coronary arteries. This technique is currently gaining acceptance for the treatment of cerebral atherosclerotic disease. Autopsy findings of fatal complications of percutaneous transluminal angioplasty of the posterior cerebral circulation have, to our knowledge, not yet been published. We report the case of a patient with severe diffuse atherosclerosis of vertebral and basilar arteries, whose symptoms were not ameliorated with standard medical therapy. Transfemoral percutaneous transluminal angioplasty was performed in an attempt to reestablish blood flow in the posterior cerebral circulation by angioplasty of a severely stenotic basilar artery. The patient suffered a fatal complication during the procedure due to rupture of the basilar artery by the percutaneous transluminal angioplasty guidewire apparatus, leading to massive subarachnoid hemorrhage. We report the clinical and autopsy findings of this case.

Traumatic tear of the basilar artery associated with vertebral column injuries

An unusual case of traumatic basal subarachnoid hemorrhage (SAH) due to a mechanical tear of the basilar artery is reported. A 70-year-old man who had been suffering from cerebrovascular dementia was found dead in a ditch. Externally, subcutaneous hemorrhage with abrasions was observed on the left side of the forehead, face, and lower jaw, together with small contusions in the left superciliary arch. Internally, a 3-mm-long transversal tear of the basilar artery was observed, and dislocations of both C6-C7 and T1-T2 as well as a small fracture of the processus spinosus of C5 were found. No pathological vascular lesions such as aneurysms and vasculitis, other than arteriosclerosis, were observed in the vertebral-basilar system. Ethanol was not detected in the intracardiac blood or in the urine. These findings indicate that when the man fell into the ditch, severe hyperextension occurred as a result of minor blunt forces to the face, and that the traumatic tear of the basilar artery was mechanically caused by overstretching due to hyperextension of the head. It is also suggested that due to his advanced age the muscle tone of the neck might have declined, impairing its defense action, and that head hyperextension might, therefore, occur rather more readily under such conditions.

Locked-in syndrome resulting from cervical spine gunshot wound

A patient sustained a cervical spine gunshot wound resulting in immediate quadriplegia and obstruction of both vertebral arteries. After an 8-hour delay, basilar artery thrombosis occurred and resulted in locked-in syndrome. Bilateral occlusion of the vertebral arteries after penetrating cervical trauma has not been reported previously. The incidence and treatment of traumatic basilar thrombosis and locked-in syndrome is reviewed. Rapid diagnosis of ascending thrombosis and prompt treatment with hyperdynamics and anticoagulation may improve outcome.

[Traumatic basilar artery dissection presenting with "locked-in" syndrome: report of a case]

We encountered a case of traumatic basilar artery dissection presenting with "locked-in" syndrome. A 46-year-old-man fell approximately 2 meters and landed in an inverted position. He was admitted to our hospital after 4 days. He was in coma on admission, and neurological examination revealed that his pupils were 2 mm in size and reactive, the corneal reflex of both sides was absent, the pharyngeal reflex was absent, and quadriplegia was present. CT and MRI showed infarction at the ventral portion of the pons. 3D-CT and CT using a bone algorithm showed fractures of the upper clivus, the left petrous bone, and the left occipital condyle. Angiography showed a pearl and string sign at the upper basilar artery. It is suggested that the cause of the infarction of the ventral portion of the pons was the occlusion of the perforating arteries due to the basilar artery dissection, and the mechanism of the basilar artery dissection was the hyperextension or hyperflexion of the basilar artery by the movement of the brain stem caused by the traumatic impact. Repeated angiography revealed gradual improvement. Eventually he freed himself from the "locked-in" syndrome.

The role of transcranial Doppler sonography in the identification of patients at risk of cerebral and brainstem ischemia

OBJECTIVE

To review the literature pertaining to transcranial Doppler (TCD) examination of the anterior and posterior cerebral circulation. This paper focuses on the application of TCD as a screening modality for vertebral artery-induced brainstem ischemic events.

DATA SOURCES

A Medline literature search was performed. Key terms included; transcranial Doppler, vertebral artery dissection, neck trauma, stroke and vertebrobasilar system.

DATA EXTRACTION

The studies examined TCD techniques that monitor the hemodynamics of the circle of Willis. Papers pertaining to vertebral artery trauma and resulting brainstem injury were included. The validity and reproducibility of these procedures were also reviewed.

CONCLUSION

TCD procedures provide hemodynamic data pertaining to intra-arterial vertebrobasilar stenosis and extra-arterial mechanical compression of the vertebral arteries. During cervical spine positional testing, brainstem symptoms may be correlated with TCD documented perfusion deficits. TCD increases the sensitivity of the standard positional test.

Traumatic aneurysm of the basilar artery

We report a case in which a "false" aneurysm of the basilar artery developed after an assault on a patient resulting in head injuries. Diagnostic imaging and endovascular treatment are described. Formation mechanisms of traumatic intracranial aneurysms are discussed and the literature is reviewed.

Traumatic ponto-medullary tear: a case report

The aim of this report is to demonstrate the correlation between an extremely short time acting but strong force leading to incomplete rupture of the ponto-medullary junction (PMJ) accompanied by rupture of the basilar artery. Potential mechanisms involved in a combined hyperextension and axial torsion of the head followed by characteristic lesions at the PMJ are discussed. A 33-year-old male suffered a blunt head injury following a blow to the head, i.e. a head-butt. Resuscitation was performed for 45 min without success. At post mortem, there was a superficial periorbital haematoma on the right and a deep soft tissue bruise in the right fronto-parieto-temporal area, but no evidence of skull or dens axis fracture. A deep tear at the ponto-medullary junction was identified with rupture of the basilar artery, whereas at the tip of the tear, i.e. the floor of the IVth ventricle, only a thin tissue layer of about 2 mm remained intact. In contrast to the severity of these lesions, only mild subarachnoid hemorrhage was observed, but the ventricular system was filled with blood clot resulting from the retrograde flow of subarachnoid hemorrhage.

Basilar artery dissection: an early postoperative complication of aneurysm clipping. Case report

Recurrent subarachnoid hemorrhage (SAH) in the early period following successful clipping of a cerebral aneurysm is unusual. The authors report a unique case of distal basilar artery dissection and fatal SAH on the 6th day postoperatively. It is concluded that this complication was related to vascular trauma inflicted by repositioning the aneurysm clips during a seemingly uneventful procedure for a basilar artery tip aneurysm.

Enhancement of depolarization-induced contractions after endothelium denudation is not related to an impaired production of nitric oxide or prostacyclin in the rabbit basilar artery

Enhancement of the extracellular potassium ion (K+) concentration combined with endothelial injury have been suggested to occur during cerebral ischaemia-reperfusion and vasospasm after subarachnoid hemorrhage. The effect of potassium (K+) depolarization was therefore investigated in isolated segments of the rabbit basilar artery with and without an intact endothelial cell layer. Addition of potassium chloride to the organ bath induced a concentration-dependent contraction. Endothelial denudation of the artery resulted in an unstable baseline tension and a leftward shift of the K+ concentration-response curve. The K+ concentration eliciting half maximum contraction decreased from 26 mmol l-1 in the presence to 12 mmol l-1 in the absence of an intact endothelium. Nimodipine (3 x 10(-7) mol l-1) or exposure to a calcium-free medium abolished the spontaneous as well as K(+)-induced contractions. N omega-nitro-L-arginine (10(-4) mol l-1), indomethacin (3 x 10(-6) mol l-1) and glibenclamide (10(-5) mol l-1) did not affect the contractile response to K+ in intact arteries. However, N omega-nitro-L-arginine increased the baseline tension, and this effect could not be reproduced with N omega-nitro-D-arginine. Pinacidil (10(-6) mol l-1) abolished the spontaneous contractile activity in endothelium-denuded arteries and reduce the K+ sensitivity to the same level as in intact arteries. Tetraethylammonium (3 mmol l-1) and ouabain (10(-5) mol l-1) increased the basal tension and shifted the K+ concentration-response curve to the left.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of incarceration of the vertebral and basilar arteries in a longitudinal fracture of the clivus]

We report a case of incarceration of the right vertebral and basilar arteries in a longitudinal fracture of the clivus. A 80-year-old man was struck on the occiput in a traffic accident and was admitted to our hospital. He was in coma on admission. Neurological examination revealed that the left pupil was dilated, the light reflex was bilaterally sluggish, the left corneal reflex was absent, and the pharyngeal reflex was absent. Computed tomography showed fractures in the occipital bone and clivus. His general condition rapidly deteriorated, and he died 4 hours after the injury. The autopsy revealed a longitudinal fracture of the clivus incarcerating the right vertebral artery together with the origin of the basilar artery. It also revealed primary brain stem injury. We presented clinical features, mechanisms of the injury, and radiological findings for three types of clivus fracture; longitudinal, transverse, and a fracture of the lower clivus extending into the occipital condyle. It is unusual to see incarceration of the basilar or the vertebral artery in a longitudinal fracture of the clivus. We found only five reported cases. Each case presented a variety of brainstem dysfunctions. Three died of brainstem infarction, and one died of aspiration pneumonia. The remaining patient is in a chronic vegetative state. In our case, the history and autopsy findings suggested that the patient died of the primary brainstem injury. We proposed two mechanisms of incarceration; one is a midline occipital blow as in our case, and the other is axially transmitted force.

Childhood stroke after minor neck trauma: case report

Cerebral infarction after minor trauma to the neck has rarely been reported. A case is presented of a child with trauma to the vertebrobasilar artery resulting in stroke. Computerized tomography scan and angiography results are presented. Despite two subsequent, separate transient episodes of vertigo, the child had good functional recovery with complete restoration of language and cognitive function. After 28 months, residual impairments identified were a mild right-sided ataxia and hemiparesis.

Surgical treatment of unruptured aneurysms of the posterior circulation

With the ever-increasing number of intact aneurysms revealed by modern imaging, the options for their management are assuming great importance. While some knowledge has emerged as to their natural history and the results of surgical treatment of those in the anterior circulation, little information has been published concerning unruptured aneurysms arising from the posterior circulation. The authors report their experience since 1971 with 167 patients operated on for 179 unruptured vertebrobasilar aneurysms up to 25 mm in diameter. Overall, 160 aneurysms were treated by direct clip obliteration, while 19 were managed by alternative methods. Fifty-three patients (32%) had solitary aneurysms and the other 114 patients (68%) had multiple aneurysms or an associated arteriovenous malformation, which were commonly treated concurrently. Many of these coexisting vascular anomalies had ruptured in the recent or remote past, adding to the complexity of management and interpretation of specific surgical results related to the intact posterior circulation aneurysm. There were 78 documented postoperative complications including 23 systemic complications, seven postoperative hematomas, six brain injuries from retraction, five cases of aseptic meningitis, three instances of seizures, three wound infections, and three patients with hydrocephalus. Multiple complications occurred in 23 patients. Seventy-one of the patients with these untoward events recovered, without disability, with time or treatment. There were only six poor results and one death in the series, resulting in a 4.2% combined morbidity/mortality rate. However, since two of these poor outcomes and the single death were attributable to a coexisting aneurysm, the actual surgical morbidity related specifically to the posterior circulation aneurysm was only 2.4%. This experience suggests that non-giant, intact vertebrobasilar aneurysms can be obliterated surgically at a very low risk, and this treatment should eliminate the greater lifetime risk related to an unsecured aneurysm.

[Dissections of the vertebral artery following cervical chiropractic manipulations]

In a 37-year-old female patient complaining of increasing pain in the neck and occiput, chiropractic manipulations at the cervical vertebral column were associated with ischaemias of the brain stem presenting as vertigo, transient "locked-in" syndrome followed by vomiting, and sensorimotor hemiparesis. Digital subtraction angiography (DSA) revealed complete obstruction of the right and slight dissection of the left vertebral artery. The symptoms receded within a few days after heparinisation with 1000 IU/h intravenously. A 39-year-old female patient developed vertigo, nystagmus, tetraparesis and dysarthria two days after chiropractic intervention because of refractory pain in the neck and occiput. DSA showed embolism of the basilar artery and extensive dissections of the vertebral arteries. The basilar artery was completely recanalized after local intraarterial fibrinolysis with 50,000 IU urokinase. During the further course of treatment the symptoms receded under heparin and phenprocoumon over a period of 8 months, except for hemiparesis on the left side especially affecting the arm. Trivial traumas can result in dissections of the vertebral arteries. Severe neck pain is a frequent, typical early symptom. Hence, patients with cervical vertebral column syndromes should receive chiropractic treatment only after careful diagnosis.

Fatal thrombosis of the basilar artery due to a minor head injury

A case is reported where a 20-year-old alcohol-intoxicated man was admitted to the hospital after a minor head injury. Initially there was no neurologic disturbances or complaints but after a few hours he became comatose, and he died 4 days later without regaining consciousness. The autopsy revealed no lesions of the upper cervical spine or the vertebral arteries, but the basilar artery was occluded in its entire length. No traumatic lesions could be seen by naked eye examination of the artery, and there was no accompanying subarachnoid haemorrhage. A thorough microscopic examination, however, using step-sectioning technique revealed a significant incomplete arterial rupture with an occluding luminal thrombosis superimposed, consisting predominantly of aggregated platelets. Only the very thin adventitia separated the vascular lumen from the subarachnoid space preventing the more well known fatal complication to a minor head injury: A subarachnoid haemorrhage. To the best of our knowledge, fatal thrombosis of the basilar artery due to a minor head injury has not previously been reported. The pathogenetic mechanism seems to be identical to that underlying fatal subarachnoid haemorrhage following a similar trauma apart from the resulting arterial rupture being incomplete instead of complete.

Isolated basilar artery occlusion associated with a clivus fracture

Most vascular injuries to the brain secondary to blunt head trauma involve the internal carotid circulation. A case of isolated basilar occlusion secondary to a clival fracture is described and compared to three other cases in the literature.