Proximal M2 false aneurysm after head trauma--Case report

Ruptured proximal middle cerebral artery traumatic pseudoaneurysm treated with bypass-assisted trapping surgery: A case report

BACKGROUND

Traumatic pseudoaneurysms are rare but have a high mortality rate; therefore, immediate diagnosis is vital. Most pseudoaneurysms are in the internal carotid artery or peripheral arteries, while proximal middle cerebral artery pseudoaneurysms have rarely been reported. We present a case of ruptured traumatic pseudoaneurysm located at the M1-M2 bifurcation.

CASE DESCRIPTION

A 42-year-old man was injured in a motorcycle accident and his Glasgow coma scale score on admission was 7 (Eye opening1, Verbal response2, Motor response4 [E1V2M4]). Head computed tomography (CT) showed thick subarachnoid hemorrhage (SAH). We suspected a ruptured aneurysm, but three-dimensional CT angiography (3D-CTA) did not detect any vascular defects. Head magnetic resonance angiography showed progressive right M1 stenosis suggesting arterial dissection. 3D-CTA on day 20 showed a small aneurysm in the proximal portion of the M2. Although surgery was scheduled for day 26, suddenly left hemiparesis appeared on day 24. Head CT detected fresh SAH and emergency surgery was performed on day 25. We dissected around the ruptured point under M1 temporary occlusion with superficial temporal artery-M2 assist bypass. Contrary to our expectations, there was only a small laceration in the right M2 superior trunk. We trapped the laceration and the proximal portion of the M2 superior trunk while preserving antegrade blood flow from the M1 to the M2 inferior trunk. On the 5-month follow-up, the patient was able to walk independently.

CONCLUSION

Unreasonably thick traumatic SAH or spastic stenosis after head injury may indicate a traumatic pseudoaneurysm and require repeated neurovascular evaluation. If a pseudoaneurysm is detected, immediate surgical intervention is mandatory.

Delayed Intracerebral Hemorrhage from a Pseudoaneurysm Following a Depressed Skull Fracture

A 26-year-old male presented with delayed intracerebral hemorrhage from a ruptured distal middle cerebral artery pseudoaneurysm that followed a compound depressed skull fracture from years ago. The brain protrusion through the skull defect likely resulted in stretching and subsequent tearing of the arterial wall resulting in the pseudoaneurysm formation. No prior report of such a clinical occurrence exists in the literature. We highlight an unusual but treatable cause for intracerebral hemorrhage following surgery for traumatic brain injury.

Traumatic anterior cerebral artery aneurysms and management options in the endovascular era

Traumatic anterior cerebral artery (ACA) pseudoaneurysms are a challenge to manage. Difficult diagnosis, delayed presentation and catastrophic outcomes contribute to the overall prognosis of traumatic intracranial aneurysms. Clipping or coiling of the aneurysm and/or parent vessel occlusion are the treatment options. However, surgery and coiling both may be difficult due to limited access and the need for parent vessel preservation. Rarely, these aneurysms must be managed conservatively. We present four patients with traumatic ACA aneurysms admitted to our center in the last 10 months. Three patients had pseudoaneurysms of the distal ACA and one had an aneurysm arising from a cortical branch of the ACA. Their clinical presentations and management, along with outcomes, are discussed as well as the dilemmas associated with them. Three patients were managed by clipping and coiling while one was managed conservatively. The diagnosis was made relatively early in three patients while delayed subarachnoid hemorrhage led to diagnosis in the fourth. Although the overall prognosis remains grim, with high mortality and morbidity rates, both microsurgical and interventional management of these traumatic aneurysms may be useful, if detected early before rupture. Expectant management and surveillance may be required in a select group of patients.

Clinical Analysis of Traumatic Cerebral Pseudoaneurysms

Objective

Traumatic pseudoaneurysms are rare but life-threatening lesions. We investigated the patients with these lesions to clarify their clinical characteristics and therapeutic strategies and we also reviewed the literatures on the treatment principles, possible options, and outcomes.

Methods

There were a total of 8 patients who were treated with traumatic intracranial pseudoaneurysms between April 1980 and January 2009. Medical charts and the imaging studies were reviewed for analysis. The outcome was measured with modified Rankin Scale (mRS) score at 6 months after treatment.

Results

All 8 patients were male and the mean age was 25 years old. Six of those were located at the cavernous segment of the internal carotid artery (ICA) and the other 2 was located at the M2 segment of middle cerebral artery. The causes of trauma were car accidents in 6, penetrating injury through the orbit in 1, and slip down injury in 1 patient. Massive epistaxis or hematemesis occurred in all patients with a pseudoaneurysm at the cavernous and ophthalmic segment of the ICA. All 6 patients of the cavernous and ophthalmic ICA group showed favorable outcome of mRS 0 to 1. The outcome of patients with middle cerebral artery pseudoaneurysm was mRS 2 to 3.

Conclusion

Upon prompt diagnosis and proper treatment planning, it is possible to achieve favorable outcome in these patients. Lesions located at the cavernous segment of the ICA favored endovascular treatment while those at the middle cerebral artery favored surgical treatment.

Delayed Deterioration in Isolated Traumatic Subarachnoid Hemorrhage

BACKGROUND

Isolated traumatic subarachnoid hemorrhage (SAH) in association with mild traumatic brain injury is considered to be a less severe finding that is not likely to require surgical intervention. No previous reports have described cases warranting craniotomy for isolated traumatic SAH by itself.

CASE DESCRIPTION

We report 2 cases of minor head trauma with isolated traumatic SAH that showed delayed clinical deterioration requiring immediate surgical intervention. Initial computed tomography showed isolated traumatic SAH in the basal cistern and Sylvian fissure in both cases. Angiography showed no aneurysmal source. Within 24 hours of each accident, both disturbance of consciousness and hemiparesis deteriorated. Follow-up computed tomography showed formation of intracerebral hematoma adjacent to the Sylvian fissure. Intraoperative findings showed abruption injury of a perforating branch arising from the middle cerebral artery (MCA) as the cause of bleeding. Impact at the time of injury could have caused traction on the MCA in the Sylvian fissure, resulting in abruption of the perforator.

CONCLUSIONS

Isolated traumatic SAH seen in the basal cistern and Sylvian fissure carries a risk of late deterioration. A possible cause of hematoma expansion is abruption of a perforating branch arising from the MCA at the time of head injury. When hematoma expansion is identified, surgical evacuation of the hematoma is indicated. Surgical evacuation should be safely performed with the knowledge of the point of bleeding in such patients.

"Real time" angiographic evidence of "pseudoaneurysm" formation after aneurysm rebleeding

BACKGROUND

Pseudoaneurysms occur at the rupture site of true aneurysms and appear as irregularly shaped and partially thrombosed outpouchings of the main sac. Recanalization of thrombi inside pseudoaneurysmal sac is one of the putative mechanisms of rebleeding of unsecured aneurysms and of coil migration after endovascular treatment. We document "real time" pseudoaneurysm formation after rerupture of an anterior communicating artery aneurysm.

METHODS

Case report.

RESULTS

A 55-year-old man with aneurysmal subarachnoid hemorrhage from an anterior communicating aneurysm underwent catheter angiography. After the diagnostic angiogram while awaiting for the anesthesia team to proceed with endotracheal general anesthesia, a seizure occurred. Rebleeding was suspected and confirmed by a dynamic CT in the angio suite. A repeat angiogram showed a pseudoaneurysm arising from the previously ruptured aneurysm which had not been present on the original angiogram a few minutes earlier. Uneventful coiling of the aneurysm was undertaken and the patient was discharged home a week later.

CONCLUSIONS

We document angiographic formation of a "pseudoaneurysm" at the site of rupture of an anterior communicating artery aneurysm. "Pseudoaneurysm" formation occurs after rupture of an intracranial aneurysm. They represent a weak spot in the aneurysm sac at the site of rupture and probably the result of persistent flow within the clot forming at the site of rupture. Presence of a pseudoaneurysm with characteristic angiographic features like the one herein described represents an unstable area within the aneurysm. This case also highlights the observation that, in patient harboring unsecured ruptured aneurysms, seizures or seizures-like phenomena are the clinical expression of rebleeding unless proven otherwise.

The use of routine imaging data in diagnosis of cerebral pseudoaneurysm prior to angiography

PURPOSE

A false aneurysm is rare and underdiagnosed complication of intracranial hemorrhage. Objective of the study was to point out diagnostic imaging signs of false aneurysm and to determine frequency and diagnostic significance of these signs.

MATERIALS AND METHODS

Cerebral arteriography performed in our center from November 2007 to September 2010 revealed the false aneurysm in 8 patients (4 male, 4 female, mean age was 38 years). During the same angiographic procedure 6 patients were treated by endovascular embolization using coils, mixture of Histoacryl and Lipiodol or Onyx (liquid embolic material). Authors retrospectively analyzed preprocedural studies (computed tomography, magnetic resonance imaging) and angiographic findings to identify signs specific to false aneurysm.

RESULTS

Computed tomographic findings that are not specific but should raise suspicion of the false aneurysm include: enlargement of parenchymal hematoma dimensions, unusual or delayed evolution of hematoma and spot sign associated with acute hematoma expansion. More specific signs can be revealed in digital subtraction angiography that shows a globular shaped neckless aneurysmal sac, delayed filling and emptying of contrast agent and stagnation of contrast with regard to the head position.

CONCLUSION

Although preangiographic imaging studies findings in patients with false aneurysms are not specific, they should lead to angiographic validation, especially enlarging parenchymal hematoma and atypical hematoma evolution. Digital subtraction angiography makes it possible to diagnose the lesion and to use endovascular embolization techniques, which are currently the method of choice for treatment of pseudoaneurysms.

Traumatic middle cerebral artery aneurysm: case report and review of the literature

Traumatic intracranial aneurysms are rare. A case of traumatic middle cerebral artery aneurysm was presented. A 66-year-old man sustained a severe head injury in a bicycle accident. Serial computed tomography and angiography showed the delayed intracerebral hemorrhage caused by the traumatic middle cerebral artery aneurysm. The aneurysm was trapped and removed. Histological examination clearly revealed the pseudoaneurysm. Traumatic middle cerebral aneurysms were reviewed.

Imaging of Traumatic Neurovascular Injury

Traumatic injury to the major vessels of the head and neck can result in potentially devastating neurologic sequelae. Until recently, conventional angiography was the primary imaging modality used to evaluate these often challenging patients. Advances in cross-sectional imaging have improved the ability to screen for these lesions, which have been found to be more common than previously thought; however, accepted protocols of imaging evaluation have not yet been fully established. This article presents a general approach to the patient with suspected neurovascular injury. This includes a discussion of the histopathologic spectrum, clinical presentation, mechanisms, radiologic work-up, pertinent issues of the most common lesions, and some of the endovascular techniques used in their management.

Pseudoaneurysm formation at the rupture site of a middle cerebral artery aneurysm--case report

A 42-year-old man suffered subarachnoid hemorrhage manifesting as sudden severe headache one month before admission. On admission, his headache had subsided and he had no neurological deficits. Cerebral angiography demonstrated an aneurysm originating from the bifurcation of the right middle cerebral artery. The aneurysm was irregular, with a snowman-like shape. Neck clipping of the aneurysm was carried out through a right pterional approach. Intraoperatively, a red, pulsating sac mimicking a blood clot (the snowman's "head") was located over the yellowish, thick-walled portion of the aneurysm. Exploration around the aneurysm detached the red sac from the thick-walled portion of the aneurysm. There was a small tear in the apex of the thick-walled aneurysm sac. A Sugita clip was applied to the neck of the true aneurysm. The postoperative course was uneventful and he was discharged one month later without neurological deficits. Histological examination of the red-colored sac showed the features of pseudoaneurysm. The red sac may have been a pseudoaneurysm covering the rupture site of the true aneurysm.