Cavernous carotid pseudoaneurysm following transsphenoidal surgery

Beware of epistaxis: fatal pseudoaneurysm rupture 30 years after treatment of acromegaly

We present a fatal complication of treatment in a patient with early-onset acromegaly, treated with two transsphenoidal operations, radiotherapy, radiosurgery and pegvisomant. He was diagnosed in his 30s, and controlled from his 40s, with stable residual tumour within the left cavernous sinus. In his 60s, 30 years after surgery/radiotherapy and 14 years after radiosurgery, he developed recurrent episodes of mild epistaxis. A week later, he presented at his local hospital's emergency department with severe epistaxis and altered consciousness. He was diagnosed with a ruptured internal carotid artery (ICA) pseudoaneurysm, but unfortunately died before treatment could be attempted.ICA pseudoaneurysms are rare complications of surgery or radiotherapy and can present with several years of delay, often with epistaxis. This case highlights the importance of life-long monitoring in patients with previous pituitary interventions and early recognition of epistaxis as a herald sign of a potentially catastrophic event, thus leading to timely treatment.

Rupture from cavernous internal carotid artery pseudoaneurysm 11 years after transsphenoidal surgery

Carotid artery pseudoaneurysm is a rare complication of transsphenoidal surgery, usually diagnosed within 90 days post procedure. Sequelae of pseudoaneurysm rupture, such as severe epistaxis or carotid cavernous fistula (CCF), have significant morbidity and mortality. A case of epistaxis from pseudoaneurysm rupture over a decade after transsphenoidal surgery is presented, with staged treatment using coiling, endonasal mucosal flap repair and interval flow-diverting stent insertion. This case illustrates that pseudoaneurysm rupture occurs regardless of time course after transsphenoidal surgery, and treatment strategies using combined endovascular and endonasal techniques are reviewed.

Intracranial Pseudoaneurysms: Evaluation and Management

Intracranial pseudoaneurysms account for about 1% of intracranial aneurysms with a high mortality. The natural history of intracranial pseudoaneurysm is not well-understood, and its management remains controversial. This review provides an overview of the etiology, pathophysiology, clinical presentation, imaging, and management of intracranial pseudoaneurysms. Especially, this article emphasizes the factors that should be considered for the most appropriate management strategy based on the risks and benefits of each treatment option.

Pipeline embolization for an iatrogenic intracranial internal carotid artery pseudoaneurysm after transsphenoidal pituitary tumor surgery: Case report and review of the literature

Intracranial pseudoaneurysms are uncommon and among the most difficult lesions to treat with surgery or endovascular means without parent artery sacrifice. Here, we report on a patient who underwent successful treatment using a flow-diverting stent for an iatrogenic intracranial internal carotid artery pseudoaneurysm following a vessel injury after endoscopic pituitary tumor resection via the transsphenoidal approach. A 62-year-old man with a Rathke's cleft cyst presenting with bitemporal hemianopia and progressive decline of left visual acuity underwent endoscopic transsphenoidal pituitary tumor resection. During dura incision, brisk arterial bleeding was encountered from the right internal carotid artery. Immediate packing was performed, and hemostasis was achieved. Three days after the vessel injury, an angiography revealed a pseudoaneurysm (2.9 × 2.1 mm) at the cavernous segment of the right internal carotid artery, which showed enlargement on follow-up magnetic resonance imaging at six days postoperatively. Pipeline embolization was performed nine days after the vessel injury. Angiography performed one month after Pipeline embolization revealed significant stagnation but not complete occlusion of blood flow inside the pseudoaneurysm cavity. Dual antiplatelet therapy was replaced with single antiplatelet therapy. Follow-up angiograms three months after Pipeline embolization confirmed complete obliteration of the pseudoaneurysm and successful endoluminal reconstruction of the damaged vessel. Despite the possibility of short-term bleeding and the need for dual antiplatelet therapy administration for a certain period, the use of flow-diverting stents is a feasible vessel-sparing option in the management of intracranial internal carotid artery pseudoaneurysms resulting from transsphenoidal surgery injuries if intraoperative hemodynamic stability can be achieved with effective packing.

Platelet activation by crushed and uncrushed muscle: a flow cytometry analysis

BACKGROUND

Crushed autologous muscle is used in skull base surgery in the acute phase of major arterial hemorrhage to stop bleeding. The mechanism of this is not yet clear, but is thought to involve the formation of a platelet plug, which seals the vessel wall defect but still allows ongoing blood flow to the brain.

METHODS

In this study we use flow cytometry to replicate the in-vivo actions of crushed muscle on platelets in whole blood. We compare the ratio of activation of platelets exposed to crushed and uncrushed muscle supernatant in control patients and in patients on antiplatelet agents.

RESULTS

Crushed muscle activated platelets to a higher degree than uncrushed muscle: 5.18-fold greater in control blood (p = 0.002); 6.53-fold greater in aspirin-exposed blood (p < 0.0001); and 9.4-fold greater in clopidogrel-exposed blood (p < 0.0001).

CONCLUSION

Crushed muscle caused a consistently increased ratio of platelet activation when compared with uncrushed muscle across all groups, adding to the evidence that at least part of its clinical effect is the result of platelet activation.

Endovascular management of internal carotid artery injuries secondary to endonasal surgery: case series and review of the literature

OBJECTIVE Internal carotid artery (ICA) injury is a rare but severe complication of endonasal surgery. The authors describe their endovascular experience managing ICA injuries after transsphenoidal surgery; they review and summarize the current literature regarding endovascular techniques; and they propose a treatment algorithm based on the available evidence. METHODS A retrospective review of 576 transsphenoidal pituitary adenoma resections was performed. Cases of ICA injury occurring at our institution and transfers from other hospitals were evaluated. Endovascular treatments for ICA injury reported in the literature were also reviewed and summarized. RESULTS Seven cases were identified from the institutional cohort (mean age 46.3 years, mean follow-up 43.4 months [1-107 months]) that received endovascular treatment for ICA injury. Five injuries occurred at our institution (5 [0.9%] of 576), and 2 injuries occurred at outside hospitals. Three patients underwent ICA sacrifice by coil placement, 2 underwent lesion embolization (coil or stent-assisted coil placement), and 2 underwent endoluminal reconstruction (both with flow diversion devices). Review of the literature identified 98 cases of ICA injury treated with endovascular methods. Of the 105 total cases, 46 patients underwent ICA sacrifice, 28 underwent lesion embolization, and 31 underwent endoluminal reconstruction. Sacrifice of the ICA proved a durable solution in all cases; however, the rate of persistent neurological complications was relatively high (10 [21.7%] of 46). Lesion embolization was primarily performed by coil embolization without stenting (16 cases) and stent-assisted coiling (9 cases). Both techniques had a relatively high rate of at least some technical complication (6 [37.5%] of 16 and 5 [55.6%] of 9, respectively) and major technical complications (i.e., injury, new neurological deficit, or ICA sacrifice) (5 [31.3%] of 16 and 2 [22.2%] of 9, respectively). Endoluminal reconstruction was performed by covered stent (24 cases) and flow diverter (5 cases) placement. Covered stents showed a reasonably high rate of technical complications (10 [41.7%] of 24); however, 8 of these problems were resolved, leaving a small percentage with major technical complications (2 [8.3%] of 24). Flow diverter placement was also well tolerated, with only 1 minor technical complication. CONCLUSIONS Endovascular treatments including vessel sacrifice, coil embolization (with or without stent assistance), and endoluminal reconstruction offer a tailored approach to ICA injury management after endonasal surgery. Vessel sacrifice remains the definitive treatment for acute, uncontrolled bleeding; however, vessel preservation techniques should be considered carefully in select patients. Multiple factors including vascular anatomy, injury characteristics, and risk of dual antiplatelet therapy should guide best treatment, but more study is needed (particularly with flow diverters) to refine this decision-making process. Ideally, all endovascular treatment options should be available at institutions performing endonasal surgery.

Hemostasis in Endoscopic Endonasal Skull Base Surgery

William Halsted established the basic principles of modern surgical technique highlighting the importance of meticulous hemostasis and careful tissue handling. These concepts hold true today and are even more critical for endoscopic visualization, making hemostasis one of the most relevant cornerstones for the safe practice of endoscopic endonasal surgery (EES) of the skull base. During preoperative assessment, patients at higher risk for serious hemorrhagic complications must be recognized. From an anatomical point of view, EES can be grossly divided in two major components: sinonasal surgery and sellar-cranial base surgery. This division affects the choice of appropriate technique for control of bleeding that relies mainly on the source of hemorrhage, the tissue involved, and the proximity of critical neurovascular structures. Pistol-grip or single-shaft instruments constitute the most important and appropriately designed instruments available for EES. Electrocoagulation and a variety of hemostatic materials are also important tools and should be applied wisely. This article describes the experience of our team in the management of hemorrhagic events during EES with an emphasis on technical nuances.

Intracranial pseudoaneurysm after intracranial pressure monitor placement

Traumatic intracranial pseudoaneurysms are a rare but severe complication following arterial injury. Pseudoaneurysm formation can occur secondary to blunt or penetrating trauma or iatrogenic injury. We report a case of traumatic pseudoaneurysm secondary to placement of an intracranial pressure (ICP) monitor. A 27-year-old man was involved in a motorcycle accident resulting in multiple intracranial hemorrhages. The patient underwent craniectomy and placement of an ICP monitor. 17 days later he developed dilation of his left pupil, with imaging demonstrating a new hemorrhage in the vicinity of the previous ICP monitor. A cerebral angiogram confirmed a left-sided distal M4 pseudoaneurysm which was treated by n-butyl cyanoacrylate embolization. Intracranial pseudoaneurysm formation following neurosurgical procedures is uncommon. Delayed intracranial hemorrhage in a region of prior intracranial manipulation, even following a procedure as 'routine' as placement of an ICP monitor, should raise the suspicion for this rare but potentially lethal complication.

Intracranial pseudoaneurysm after intracranial pressure monitor placement

Traumatic intracranial pseudoaneurysms are a rare but severe complication following arterial injury. Pseudoaneurysm formation can occur secondary to blunt or penetrating trauma or iatrogenic injury. We report a case of traumatic pseudoaneurysm secondary to placement of an intracranial pressure (ICP) monitor. A 27-year-old man was involved in a motorcycle accident resulting in multiple intracranial hemorrhages. The patient underwent craniectomy and placement of an ICP monitor. 17 days later he developed dilation of his left pupil, with imaging demonstrating a new hemorrhage in the vicinity of the previous ICP monitor. A cerebral angiogram confirmed a left-sided distal M4 pseudoaneurysm which was treated by n-butyl cyanoacrylate embolization. Intracranial pseudoaneurysm formation following neurosurgical procedures is uncommon. Delayed intracranial hemorrhage in a region of prior intracranial manipulation, even following a procedure as 'routine' as placement of an ICP monitor, should raise the suspicion for this rare but potentially lethal complication.

Cavernous internal carotid artery aneurysm after radiotherapy presenting with external ophthalmoplegia

Cranial radiotherapy could cause several types of vasculopathies, which include atherosclerotic occlusive diseases, moyamoya disease, and aneurysm formation. To our knowledge, radiation-induced aneurysms of the internal carotid artery (ICA) are extremely rare. Here, we report a 68-year-old woman who presented with external ophthalmoplegia caused by radiotherapy after the transsphenoidal surgery for metastastic tumor of the clivus region, and the angiography demonstrated a giant aneurysm of the cavernous ICA. After the ICA ligation, the patient recovered well without brain ischemia with a 6-month-long follow-up. The present case is extremely rare with external opthalmoplegia caused by the giant cavernous ICA aneurysm, and the radiotherapy after transsphenoidal surgery might have been critical in the formation of the aneurysm.

Aneurysmal remodeling in the circle of Willis after carotid occlusion in an experimental model

Carotid occlusions are associated with de novo intracranial aneurysm formation in clinical case reports, but this phenomenon is not widely studied. We performed bilateral carotid ligation (n=9) in rabbits to simulate carotid occlusion, and sham surgery (n=3) for control. Upon euthanasia (n=3 at 5 days, n=6 at 6 months post ligation, and n=3 at 5 days after sham operation), vascular corrosion casts of the circle of Willis (CoW) were created. Using scanning electron microscopy, we quantified gross morphologic, macroscopic, and microscopic changes on the endocasts and compared findings with histologic data. At 5 days, CoW arteries of ligated animals increased caliber. The posterior communicating artery (PCom) increased length and tortuosity, and the ophthalmic artery (OA) origin presented preaneurysmal bulges. At 6 months, calibers were unchanged from 5 days, PComs further increased tortuosity while presenting segmental dilations, and the OA origin and basilar terminus presented preaneurysmal bulges. This exploratory study provides evidence that flow increase after carotid occlusion produces both compensatory arterial augmentation and pathologic remodeling such as tortuosity and saccular/fusiform aneurysm. Our findings may have considerable clinical implications, as these lesser-known consequences should be considered when managing patients with carotid artery disease or choosing carotid ligation as a therapeutic option.

Pipeline Embolization Device as primary treatment for blister aneurysms and iatrogenic pseudoaneurysms of the internal carotid artery

BACKGROUND

Blood blister type aneurysms (BBAs) and pseudoaneurysms create a unique treatment challenge. Despite many advances in open surgical and endovascular techniques, this subset of patients retains relatively high rates of morbidity and mortality. Recently, BBAs have been treated with flow-diverting stents such as the Pipeline Embolization Device (PED) with overall positive results.

METHODS

Four patients presented with dissecting internal carotid artery (ICA) aneurysms treated with the PED (two BBAs presenting with subarachnoid hemorrhage (SAH), two pseudoaneurysms after injury during endoscopic trans-sphenoidal tumor surgery).

RESULTS

Three patients had a successful angiographic and neurological outcome. One patient with a BBA re-ruptured during initial PED placement, again in the postoperative period, and later died. Primary PED treatment involved telescoping stents in two patients and coil embolization supplementation in one patient.

CONCLUSIONS

The PED should be used selectively in the setting of acute SAH. Dual antiplatelet therapy can complicate hydrocephalus management, and the lack of immediate aneurysm occlusion creates the risk of short-term re-rupture. PED treatment for iatrogenic ICA pseudoaneurysms can provide a good angiographic and neurological outcome.