Time-Dependent Association of Preinjury Anticoagulation on Traumatic Brain Injury-Induced Coagulopathy: A Retrospective, Multicenter Cohort Study.

BACKGROUND AND OBJECTIVES: The impact of preinjury anticoagulation on coagulation parameters over time after traumatic brain injury (TBI) has remained unclear. Based on the hypothesis that preinjury anticoagulation significantly influences the progression and persistence of TBI-induced coagulopathy, we retrospectively examined the association of preinjury anticoagulation with various coagulation parameters during the first 24 hours postinjury in 5 periods. METHODS: Data from the Japanese registry of patients with TBI aged ≥65 years admitted between 2019 and 2021 were used. Time since injury was classified into 5 categories through a graphical analysis of coagulation parameters. We examined the association between preinjury anticoagulation and the platelet count, prothrombin time-international normalized ratio (PT-INR), activated partial thromboplastin time (APTT), D-dimer level, and fibrinogen level during each period by analysis of covariance using 10 clinical factors as confounding factors. RESULTS: Data from 545 patients and 795 blood tests were analyzed. The patients' mean age was 78.9 years, and 87 (16%) received anticoagulation therapy. The preinjury anticoagulation group had significantly greater Rotterdam computed tomography scores and poorer outcomes at discharge than the control group, with significantly lower D-dimer levels and higher fibrinogen levels. Analysis of covariance revealed significant associations between the D-dimer level and preinjury anticoagulation within 2 to 24 hours postinjury, APTT and preinjury anticoagulation within 1 to 24 hours, and PT-INR and preinjury anticoagulation throughout all periods up to 24 hours postinjury. CONCLUSION: Despite more severe TBI signs and poorer outcomes, the preinjury anticoagulation group had significantly lower D-dimer levels, especially within 2 to 24 hours postinjury. Thus, D-dimer levels during this period may not reliably represent TBI severity in patients receiving anticoagulation therapy before injury. Preinjury anticoagulation was also associated with an elevated PT-INR and prolonged APTT from early to 24 hours postinjury, highlighting the importance of aggressive anticoagulant reversal early after injury.

Effects of dual antiplatelet therapy (DAPT) compared to single antiplatelet therapy (SAPT) in patients with traumatic brain injury.

Japan is one of the world's most aging societies and the number of elderly patients taking antithrombotic drugs is increasing. In recent years, dual antiplatelet therapy (DAPT), in which two antiplatelet drugs are administered, has become common in anticipation of its high therapeutic efficacy. However, there are concerns about increased bleeding complications in use of DAPT. Therefore, the goal of this study was to investigate the effects of DAPT in patients with traumatic brain injury (TBI). A prospective, multicenter, observational study was conducted from December 2019 to May 2021 to examine the effects of antithrombotic drugs and reversal drugs in 721 elderly patients with TBI. In the current study, the effect of DAPT on TBI was examined in a secondary analysis. Among the registered patients, 132 patients taking antiplatelet drugs only were divided into those treated with single antiplatelet therapy (SAPT) (n=106) and those treated with DAPT (n=26) prior to TBI. Glasgow Coma Scale (GCS) on admission, pupillary findings, course during hospitalization, and outcome were compared in the two groups. A similar analysis was performed in patients with a mild GCS of 13-15 (n=95) and a moderate to severe GCS of 3-12 (n=37) on admission. The DAPT group had significantly more males (67.0 % vs. 96.2 %), a higher severity of illness on admission, and a higher frequency of brain herniation findings on head CT (21.7 % vs. 46.2 %), resulting in significantly higher mortality (12.3 % vs. 30.8 %). The only significant factor for mortality was severity on admission. The rate of DAPT was significantly higher in patients with a moderate to severe GCS on admission, and DAPT was the only significant factor related to severity on admission. These findings suggest that the severity of injury on admission influences the outcome six months after injury, and that patients with more severe TBI on admission are more likely to have been treated with DAPT compared to SAPT.

The current status of reversal therapy in Japan for elderly patients with head injury treated with antithrombotic agents: A prospective multicenter observational study.

Background: Acute exacerbation of head injury in elderly patients due to use of antithrombotic agents has become a concern in countries with aging populations. Reversal agents are recommended for treatment, but its usage is unclear. Therefore, we conducted a prospective observational study in this patient population to monitor usage of reversal therapy. Methods: The subjects were 721 elderly patients aged ≥65 years old who were hospitalized in 15 centers from December 2019 to May 2021. Patients were divided into groups who did not receive antithrombotic agents (Group A), who received antithrombotic agents, but did not receive reversal therapy (Group B), and were treated with antithrombotic agents and reversal therapy (Group C). Age, gender, mechanism of injury, neurologic and imaging findings on admission, clinical course after admission and surgery, outcomes and complications were compared among these groups. Time from injury to reversal therapy was examined based on outcomes to investigate trends in the timing of administration of the reversal agent. Results: Acute exacerbation during the clinical course occurred in 9.8 %, 15.8 % and 31.0 % of cases in Groups A, B and C, respectively, and differed significantly among the groups. On head CT, the incidences of hematoma were 35.7 %, 36.5 % and 60.4 %, respectively, with this incidence being significantly higher in Group C; and the respective rates of craniotomy were 18.8 %, 14.0 % and 50.9 %, again with this rate being significantly higher in Group C. The good outcome and mortality rates were 57.1 %, 52.5 % and 35.8 %, and 14.5 %, 18.0 % and 24.5 %, respectively, and both were poorest in Group C. Times from injury to treatment with a reversal agent were significantly shorter in patients without compared to those with acute exacerbation (405.9 vs. 880.8 min) and in patients with favorable outcomes compared to those with unfavorable outcomes (261.9 vs. 543.4 min). Conclusion: Similarly to previous studies, the incidence of acute exacerbation was increased by use of antithrombotic agents. These results suggest that patients in Japan who require hematoma evacuation due to symptom exacerbation tend to be treated with reversal agents. Although it is difficult to assess the efficacy of reversal therapy from this study, earlier treatment with reversal agents before the occurrence of acute exacerbation may be useful to improve outcomes.

Retrospective Observational Study of Patients With Subdural Hematoma Treated With Idarucizumab.

Use of anticoagulants is increasing with the aging of societies. The safe first-line drug is likely to be a direct oral anticoagulant (DOAC), but outcomes of treatment of traumatic brain injury (TBI) with anticoagulants are uncertain. Therefore, we examined the clinical effect of idarucizumab as reversal therapy in elderly patients with TBI who were treated with dabigatran. A retrospective multi-center observational study was performed in patients ≥65 years of age who developed acute traumatic subdural hematoma during treatment with dabigatran and underwent reversal therapy with idarucizumab. The items examined included patient background, neurological and imaging findings at arrival, course after admission, complications, and outcomes. A total of 23 patients were enrolled in the study. The patients had a mean age of 78.9 years. Cause of TBI was fall in 60.9% of the subjects. Mean Glasgow Coma Scale score at arrival was 8.7; anisocoria was present in 31.8% of cases. Exacerbation of consciousness was found in 30.4%, but only in 13.3% of subjects treated with idarucizumab before consciousness and imaging findings worsened. Dabigatran was discontinued in 81.8% of cases after hematoma development, with a mean withdrawal period of 12.1 days. The favorable outcome rate was 21.7%, and mortality was 39.1%. In multi-variate analysis, timing of idarucizumab administration was associated with a favorable outcome. There were ischemic complications in 3 cases (13.1%), and all three events occurred ≥7 days after administration of idarucizumab. These findings suggest that in cases that develop hematoma during treatment with dabigatran, it is important to administer idarucizumab early and restart dabigatran after conditions stabilize.

Analysis of relationship between loading condition and cranial cracking pattern using a three-dimensional finite element model.

BACKGROUND: A hairline crack on the cranium can occur even under a small external load or impact and are thus often observed in patients who have experienced an accidental fall or collision. Typical finite element analysis is useful to analyze the stress concentration or the propagation of stress waves. However, a stress propagation model does not accurately reproduce the features of hairline cracks on the cranium. The objective in this study was to reproduce cranial hairline cracks. METHODS: A three-dimensional finite element model of the cranial bone was developed from a patient CT images. The model consists of the frontal, parietal, occipital and temporal bones, and the bones are connected with the sutures. Additionally, the model comprised three layers; the external and internal tables and the diploe. The model was analyzed using the extended finite element method (X-FEM), and a forming limit diagram (FLD) was embedded in the model. In this study, the model was symmetrized bilaterally using the model developed from the left side of the skull. The FLD in this study was assumed to be a relationship between the maximum and minimum strains when a fracture occurs. A total of 13 typical loadings were applied to the model: loading points on the top, left, and back of the cranium were considered, and at each loading point, loads were applied with four or five different directions, namely perpendicular to the cranium and inclined in the anterior, posterior, superior, or inferior at an angle of 45∘. RESULTS: Under all loading conditions, many small cracks formed radially at the loading points. Moreover, some large cracks formed under the certain loading conditions. The crack shapes on the top and left side could be associated with the specific loading directions, whereas cracks on the back did not show distinguishing characteristics depending on the loading directions. The present model was reproduced anatomically and morphologically, and the results were similar to those obtained in previous cadaver experiments. CONCLUSIONS: Through X-FEM analysis of the FE model embedded with an FLD, hairline cracks in the cranium were reproduced, and a few crack shapes were identified as potential markers for estimating the loading conditions.

A case of tandem stenoses at the proximal common and internal carotid arteries treated with transbrachial stenting: a case report.

The transfemoral approach is a common technique for carotid artery stenting. However, it has the risk of distal embolism when stenting for a stenosis of the proximal common carotid artery because of poor stability of the guiding catheter resulting in difficulty in setting the embolic protection device prior to stenting. We present a novel therapeutic approach and technique for the treatment of tandem carotid stenoses including the proximal common carotid artery. A 63-year-old man presented with double stenoses at the common carotid artery and internal carotid artery. We used a transbrachial sheath guide that had a 6 Fr (2.24 mm, 0.088 inch) internal diameter and was 90 cm long, and was specifically designed for direct cannulation to the common carotid artery, like a modified Simmons catheter. Because the sheath guide positioned in the aortic arch made it possible to introduce safely the embolic protection device distal to the internal carotid artery stenosis without touching the plaque at the stenosis with no use of any coaxial catheters or guidewires, carotid artery stenting for tandem stenoses could be successfully carried out. The postoperative course was uneventful. In carotid artery stenting, especially for stenosis of the proximal common carotid artery, the sheath guide designed for transbrachial carotid cannulation was useful in stenting the tandem carotid stenoses.

Surgical removal of an arteriovenous malformation in the anterior perforated substance in a pregnant woman.

BACKGROUND: A tailor-made treatment is often required in arteriovenous malformations (AVMs) depending on the individual situation. In most cases, treatment strategy is usually determined according to the patient's Spetzler-Martin grade. However, in the present case, we were not able to treat the patient following the usual guidelines because of neurological symptoms and pregnancy. CASE DESCRIPTION: We describe a rare case of a 31-year-old woman in the 15th week of gestation who presented with an AVM in the anterior perforated substance (APS). She suffered a sudden coma and hemiplegia. A computed tomographic scan showed an enhanced mass and a huge hematoma in the basal ganglia and temporal lobe. The hematoma was successfully evacuated in an endoscopic procedure. Angiography showed that a 25-mm nidus in the APS was fed by the anterior choroidal arteries (AChAs) and the lenticulostriate arteries (LSAs). Therefore, we attempted to remove the nidus because the patient became alert with mild aphasia and hemiparesis 10 days after hemorrhage. The feeding arteries were cut under motor evoked potential (MEP) monitoring, and the nidus was totally resected leaving two of four AChAs and a single artery with several LSAs. The postoperative course was uneventful, and she gave birth to a healthy baby by caesarian delivery 122 days after the hemorrhage with only minor sequelae. CONCLUSIONS: Surgical strategy with a device-administered anesthesia are suitable for removing large AVMs even in pregnant women and for the successful outcome of their pregnancies. Even after recovering from a coma and hemiplegia, MEP monitoring is effective for removing large AVMs even when located in the APS.

Risk Factors of Contralateral Microembolic Infarctions Related to Carotid Artery Stenting.

This study sought to analyze the incidence of contralateral microembolic infarctions (MIs) on diffusion-weighted imaging (DWI) following protected carotid artery stenting (CAS) and compared the difference of risk factors between ipsilateral and contralateral lesions. From April 2010 to March 2017, 147 CASs in 140 patients were performed. All the patients underwent DWI within 1 week before and 24 hrs after the procedures. CAS was successfully completed in 145 (98.6%) of the 147 procedures. Forty-nine (33.8%) patients with new MIs revealed on postprocedural DWI were enrolled. They were divided into ipsilateral and contralateral groups based on the side of the CAS and MIs. The ipsilateral group indicates patients with MIs exclusively on the side of CAS. The contralateral group includes patients with MIs on the opposite side of the CAS or both sides. Patients with MIs at vertebrobasilar territory were excluded. Patient characteristics, morphology of the carotid artery and aortic arch, and procedural data were retrospectively assessed and compared between the two groups. Twenty-two (15.2%) and 14 (9.7%) patients were assigned to the ipsilateral and contralateral groups, respectively. Advanced age, left-sided stenosis, severe aortic arch calcification (AAC) on chest X-ray and contralateral carotid occlusion significantly increased the occurrence of contralateral MIs. On multivariable logistic regression analysis, severe AAC was statistically more frequent in the contralateral group. In the present study, the incidences of contralateral MIs after CAS is relatively not low. Advanced aortic atherosclerosis is statistically predictive for contralateral MIs. AAC on chest X-ray is a useful finding for estimating aortic atherosclerosis in candidates for CAS.

[A Case of Multiple Atherosclerotic Fusiform Cerebral Aneurysms with Repeated Subarachnoid Hemorrhage].

Pure fusiform aneurysms without dissection are considered to have a low risk of rupture. Furthermore, aneurysm wall with atherosclerotic change tends to be less susceptible to rupture. We present a rare case of multiple atherosclerotic fusiform aneurysms associated with repeated subarachnoid hemorrhage(SAH)during a 9-year observation period. A 34-year-old woman was admitted to our hospital because of SAH. SAH with a temporal hematoma due to a fusiform aneurysm of the right middle cerebral artery(MCA)was detected using computed tomography(CT). Associated fusiform aneurysms were observed in the left posterior cerebral artery(PCA)and the left MCA. The right MCA aneurysm was occluded with angioplastic clipping. Eight years after the first onset, angioplastic clipping was performed on the other two fusiform aneurysms because of their growth. Intraoperative findings showed atherosclerotic change in the parent artery wall, similar to the right MCA aneurysms. The right MCA aneurysm ruptured again 1 year later. The aneurysm was treated with proximal occlusion combined with a bypass from the occipital artery to the distal MCA. The patient was in a stable state, although, she was disabled because of SAH damage. The effects of atherosclerotic fusiform aneurysms, which are rarely encountered, are not well known. Some studies have reported the risk of hemorrhage from these aneurysms. This case suggests the necessity of long-term follow-up for the prediction of aneurysm growth and bleeding. Moreover, proximal occlusion combined with an external bypass is better for the treatment of this type of aneurysm because angioplastic clipping is not curative.

Clinical significance of thickened sphenoid sinus mucosa in Rathke's cleft cyst.

BACKGROUND: To determine the clinical significance of thickening of the sphenoid sinus mucosa (TSSM) in Rathke's cleft cyst (RCC). METHODS: We retrospectively reviewed patients with pituitary lesions. A total of 99 patients, who underwent surgery of pituitary lesions between 2008 and 2015, were analyzed to evaluate the clinical significance of TSSM using magnetic resonance imaging. The patients with TSSM were evaluated for their characteristics. RESULTS: Of the 99 operations, 15 patients with paranasal sinusitis, direct invasion to the sellar floor, and/or a history of transsphenoidal surgery were excluded. There were 51 pituitary adenomas (PAs), 18 RCCs, and 15 other tumors. TSSM was observed in 6 patients (7.1%). Pathologies included 3 RCCs (16.7%), 1 PA (2.0%), and 2 other lesions. Three RCCs were especially analyzed. The pituitary dysfunction was found in all 3 patients with TSSM, whereas that was noted in 2 of 15 patients (13.3%) without TSSM. The sensitivity was 60%, specificity was 86.7%, and the positive predictive value was 100%. There was no significant difference in the age, thickness of TSSM, symptoms, and squamous metaplasia between patients with and without TSSM. CONCLUSIONS: TSSM occurs more frequently in RCCs than in PAs. TSSM can potentially suggest hypopituitarism in RCCs. The surgical and/or endocrinological interventions are required for preventing further endocrine deterioration.

Steroid-resistant Tolosa-Hunt syndrome with a de novo intracavernous aneurysm: A case report.

BACKGROUND: We report a case of steroid-resistant Tolosa-Hunt syndrome (THS) with recurrent bilateral painful ophthalmoplegia, accompanied with sphenoid sinusitis, pituitary abscess, and an aneurysm arising from the cavernous portion of the internal carotid artery. CASE DESCRIPTION: A 53-year-old woman suffered severe left painful ophthalmoplegia. A magnetic resonance image (MRI) revealed thickness of the left cavernous sinus (CS). Steroid was administrated under the diagnosis of THS, and the symptom transiently diminished. However, painful ophthalmoplegia fluctuated bilaterally after tapering the steroid. An MRI showed development of bilateral cavernous lesions associated with sphenoid sinusitis, pituitary abscess, and an aneurysm in the left C4 segment. Biopsy and drainage of the lesions were performed with an endoscopic transsphenoidal procedure. The histological examination showed nonspecific granulomatous inflammation. The methotrexate (MTX) was effective to reduce the CS and pituitary lesions; however, the aneurysm slightly increased and remained unchanged in size thereafter. CONCLUSIONS: To our knowledge, this is the first report of a growing de novo C4 aneurysm in THS. Surgical intervention and administration of MTX should be attempted in steroid-resistant THS. Careful observation with serial MRI and MR angiography is important to manage the complicated THS.

Ruptured dermoid cyst of the lateral cavernous sinus wall with temporary symptoms: a case report.

BACKGROUND: Dermoid cysts are non-neoplastic tumors that arise from defects in the separation of the neuroectoderm. Cyst rupture rarely occurs spontaneously and the most common symptom is headache, followed by seizure. Although many cases of ruptured dermoid cysts present with symptoms, reports of cases that are asymptomatic, or where symptoms disappear, are rare. CASE PRESENTATION: We report the case of a 66-year-old Asian man with a history of sudden onset headache who was found to have high amounts of fat material in the subarachnoid space and a fat suppression mass in the left cavernous sinus. He underwent oral steroid therapy. Five days after starting medication his headache symptoms disappeared. Routine neurological imaging was then performed without surgical procedure. Magnetic resonance imaging revealed evidence of the remains of a static lesion 6 months after his first visit. He has remained headache free for 10 months since the initial event. CONCLUSIONS: Although cases of ruptured dermoid cysts presenting with consistent symptoms have been commonly reported, until now there were few reports on asymptomatic cases or cases where symptoms disappeared. We believe that surgical intervention is unnecessary for ruptured dermoid cysts with minimal symptoms.

[Coil Embolization of a Ruptured Anterior Communicating Artery Aneurysm Forming a Pseudoaneurysm: Report of Three Cases].

The formation of an intracranial pseudoaneurysm due to a ruptured saccular aneurysm is a rare condition that exhibits characteristic angiographic findings referred to as "ghost aneurysm" or "snowman's head". Currently, no detailed information about the treatment of this condition is available. Clipping has been reported to be more effective and better for removing massive hematomas than endovascular intervention. Moreover, endovascular coil embolization during the acute phase carries a high risk of repeated aneurysm rupture due to the fragility of the pseudoaneurysmal blood clot. Here, we describe three cases of pseudoaneurysm formation following the rupture of an anterior communicating artery aneurysm, and suggest the possibility that ruptured saccular aneurysms with pseudoaneurysm formation can be treated safely and effectively with endovascular coil embolization.

Outflow occlusion with A3-A3 anastomosis for a doughnut-shaped partially thrombosed giant A2 aneurysm.

BACKGROUND: A doughnut-shaped aneurysm, which is defined as a round-shaped aneurysm composed of an intraluminar thrombus and marginal parent artery, is an extremely uncommon subtype of partially thrombosed giant aneurysms. Surgical treatment of this characteristic aneurysm is technically challenging. CASE DESCRIPTION: We report a rare case of a 79-year-old man with a symptomatic doughnut-shaped giant aneurysm at the A2 portion, which was successfully treated by outflow occlusion with an A3-A3 side-to-side anastomosis. Postoperative angiograms demonstrated no filling of the doughnut-shaped aneurysm and perfusion in the distal right anterior cerebral artery territory via the anastomosis. Follow-up magnetic resonance imaging 1 year after the surgery demonstrated significant diminution of the aneurysm. CONCLUSIONS: Outflow occlusion with distal revascularization could be an effective surgical option for such a unique aneurysm. To the best of our knowledge, this is the first report of outflow occlusion as a therapy for doughnut-shaped aneurysms.

Impact of Aneurysmal Neck Position in Endovascular Therapy for Anterior Communicating Artery Aneurysms.

Anterior communicating artery (ACoA) aneurysms have a complex architecture and many variations, making endovascular therapy more difficult in some cases. The aim of this study was to investigate whether the neck position of an aneurysm was identifiable for determining the immediate angiographic success and procedural complications in the coiling of the ACoA aneurysms. We conducted a retrospective case review of 40 patients with ACoA aneurysms treated by endovascular therapy from 2008 to 2015. The mean age was 66.8 years. Thirty-five aneurysms were ruptured; five were unruptured. For the analysis, the patients were divided into two groups according to the neck position of aneurysms: the true ACoA group, 9 patients with the neck located on the ACoA itself; and the other ACoA group, 31 patients with the neck at the junction of the A1 and A2 portions of an anterior cerebral artery. Morphological characteristics (dome size, dome direction, rate of wide neck, and angulation of aneurysms in relation to the parent artery) were analyzed along with immediate angiographic results, volume embolization ratio (VER), and procedural complications. Small aneurysms with superior dome projection and acute angulation of the aneurysm direction occurred more often in the true ACoA group. The rates of complete obliteration, VER, and procedural complications were 33.3%, 32.3%, and 22.2% in the true ACoA group and 54.8%, 36.3%, and 6.5% in the other ACoA group, respectively. True ACoA aneurysms could present an anatomical difficulty in endovascular coiling. Aneurysmal neck position should be accurately assessed to achieve successful embolization of the ACoA aneurysms.

The "temporary caging" technique for catheter navigation in patients with intracranial wide-necked aneurysms.

Endovascular treatment of wide-necked aneurysms with preservation of the parent artery remains a challenge. The authors describe a novel and simple technique to navigate a balloon or stent-delivery catheter across a wide-necked aneurysm in which previously existing methods could have failed to pass the catheter across the neck of the aneurysm, which we have named "temporary caging" technique. The technical results using this method are presented in 6 cases.

Percutaneous transluminal angioplasty in a patient with internal carotid artery stenosis following gamma knife radiosurgery for recurrent pituitary adenoma.

BACKGROUND: Intracranial vascular complications following radiosurgery are extremely rare. CASE DESCRIPTION: We report a case of stenosis in the internal carotid artery 5 years after gamma knife radiosurgery for a recurrent pituitary adenoma. Percutaneous transluminal angioplasty was performed successfully with anatomical and functional improvement. CONCLUSION: These results suggested the importance of monitoring for arterial stenosis in the long-term follow-up. Moreover, this is the first case of endovascular treatment as an effective therapy for intracranial arterial stenosis due to radiotherapy.

Intraoperative head rotation for clipping anterior communicating artery aneurysms.

BACKGROUND: The anterior interhemispheric approach provides wide exposure of the anatomy around the anterior communicating artery aneurysm. A disadvantage of this approach is that splitting the interhemispheric fissure is a complicated surgical maneuver. One solution is to hold the fissure horizontally in the operation field. Surgical procedures for bicoronal scalp incision and craniotomy are difficult in the horizontal head position. We developed a modified low anterior interhemispheric approach to minimize damage to the frontal lobe and olfactory nerve by rotating the head after opening the dura. METHODS: The head is fixed in a prerotated Sugita head holder in a neutral head position. Bicoronal scalp incision and frontal craniotomy are performed and the head holder is rotated 30 degrees clockwise to allow gravity to retract the right frontal lobe. The surgeon can then move to the right side of the patient to obtain a horizontal operation field parallel to the interhemispheric fissure. RESULTS: This method was used for 12 patients in the past 6 years. All aneurysms were successfully clipped without any complications related to the procedure. Damage to the frontal lobe was avoided and the olfactory nerve was preserved in all the patients. CONCLUSION: Intraoperative head rotation minimizes surgical damage to the neural structures in the anterior interhemispheric approach.

Acute phase endovascular intervention on a pseudoaneurysm formed due to rupture of an anterior communicating artery aneurysm.

A 79-year-old woman presented with a subarachnoid hemorrhage. Angiography revealed pseudoaneurysm formation due to rupture of a true saccular anterior communicating artery aneurysm. Coil embolization, limited to the true aneurysm, was performed successfully with a favorable clinical outcome. This procedure can be considered as an alternative treatment option for similar aneurysms in cases where surgical clipping is contraindicated.

[Characteristics of cerebral aneurysm clips based on measurements of the opening pressures: basic research using a high-pressure perfusion circuit and a porcine vessel].

BACKGROUND: The closing force of cerebral aneurysm clips is measured according to International Organization for Standardization guidelines. However, it is difficult to predict the risk of a clip using only the closing force. To investigate the clips' detailed characteristics and assess their limits, we used a high-pressure perfusion circuit and measured the critical pressure to the slipping point. METHODS: Opening pressures were measured for 3 types of Sugita clips using a high-pressure perfusion circuit and a porcine vessel. The opening pressures at different points on various blade lengths and shapes were also measured. RESULTS: The opening pressure of a short blade clip was higher than that of a long one. In a straight blade of the same length, the opening pressure of the proximal segment of a blade was higher than that at the distal segment. CONCLUSIONS: Our study showed the characteristics of various clips, such as blade length. These findings suggested that clips should be chosen on a case-by-case basis.