Total brain volume is associated with severity of transverse sinus stenosis in idiopathic intracranial hypertension.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a complex neurological condition characterized by symptoms of increased intracranial pressure of unclear etiology. While transverse sinus stenosis (TSS) is often present in patients with IIH, how and why it occurs remains unclear. METHODS: IIH patients and a set of age-matched normal controls were identified from our single-center tertiary care institution from 2016 to 2024. Brain MRIs before treatment were computationally segmented and parcellated using FreeSurfer software. Extent of TSS on MR venograms was graded using the Farb scoring system. Relationship between normalized brain volume, normalized brain-to-CSF volume, and TSS was investigated. Multiple linear regression was conducted to investigate the association between continuous variables, accounting for the covariates body mass index, sex, and age. RESULTS: In total, 84 IIH patients (mean age, 29.8 years; 87% female) and 15 normal controls (mean age, 28.1 years) were included. Overall, increasing/worsening TSS was found to be significantly associated with normalized total brain volume (p=0.018, R=0.179) and brain-to-CSF ratio volume (p=0.026, R=0.184). Additionally, there was a significant difference between controls and IIH patients with mild and severe stenosis regarding normalized total brain volume (ANCOVA, p=0.023) and brain-to-CSF ratio volume (ANCOVA, p=0.034). Likewise, IIH patients with severe TSS had a significantly higher brain-to-CSF volume compared with controls (p=0.038) and compared with IIH patients with mild TSS (p=0.038). CONCLUSIONS: These findings suggest that total brain volume is associated with extent of TSS, which may reflect extramural venous compression due to enlarged brain and/or venous hypertension with associated cerebral congestion/swelling.

Surgical treatment of brainstem cavernous malformations: an international Delphi consensus.

OBJECTIVE: Indication for surgery in brainstem cavernous malformations (BSCMs) is based on many case series, few comparative studies, and no randomized controlled trials. The objective of this study was to seek consensus about surgical management aspects of BSCM. METHODS: A total of 29 experts were invited to participate in a multistep Delphi consensus process on the surgical treatment of BSCM. RESULTS: Twenty-two (76%) of 29 experts participated in the consensus. Qualitative analysis (content analysis) of an initial open-ended question survey resulted in 99 statements regarding surgical treatment of BSCM. By using a multistep survey with 100% participation in each round, consensus was reached on 52 (53%) of 99 statements. These were grouped into 4 categories: 1) definitions and reporting standards (7/14, 50%); 2) general and patient-related aspects (11/16, 69%); 3) anatomical-, timing of surgery-, and BSCM-related aspects (22/37, 59%); and 4) clinical situation-based decision-making (12/32, 38%). Among other things, a consensus was reached for surgical timing, handling of associated developmental venous anomalies, handling of postoperative BSCM remnants, assessment of specific anatomical BSCM localizations, and treatment decisions in typical clinical BSCM scenarios. CONCLUSIONS: A summary of typical clinical scenarios and a catalog of various BSCM- and patient-related aspects that influence the surgical treatment decision have been defined, rated, and interpreted.

Impact of active dose management on radiation exposure and image quality in computed tomography: An observational study in 1315 patients.

PURPOSE: To determine the clinical impact of CT dose management team on radiation exposure and image quality. METHODS: 2026 clinical routine CT examinations of 1315 patients were evaluated retrospectively. A CT dose management team was established as an integral part of the radiological department. It identified 5 CT protocols (A-E), where national reference values were exceeded the most. Those reference values included specifically the mean volumetric CT dose index (CTDIvol) and the mean dose-length product (DLP). Baseline data (period 1) and follow up data (period 2) were obtained after reduction of tube voltage and increase of pitch or noise index. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated to compare image quality. Two-sided t-tests were performed. RESULTS: Mean CTDIvol and mean DLP of the chest protocol (A) decreased after reduction of tube voltage (P < 0.01). In the chest/abdomen/pelvis protocol (B), the increase of noise index resulted in a significant mean CTDIvol decrease (P < 0.02) without statistical significance of mean DLP (P < 0.12). In the abdomen/pelvis protocol (C), mean CTDIvol (P = 0.01) and mean DLP (P < 0.01) were significantly lower after noise index increase. In the staging of hepatocellular carcinoma (D), mean CTDIvol and mean DLP were significantly lower after increase of pitch and noise index (P < 0.01). The lung protocol (E) yielded no significant changes after modulation (P > 0.05). SNR (protocol A) was significantly higher in period 2 (P < 0.04). Protocol D showed significantly lower selected SNR and CNR (P < 0.02). CONCLUSIONS: Establishing an operating dose management team as a standard for good clinical practice helps to considerably reduce CT radiation dose while preserving image quality.

Optimal pediatric dosing of anti-platelet agents for pipeline stent embolization -a case report and review of the literature.

BACKGROUND: Various strategies are emerging for dosing antiplatelet therapies in preparation for pipeline stent embolization in adults. Hyper-response is associated with hemorrhagic complications. Hypo-response is associated with thromboembolic events. Dosing of antiplatelet agents is highly variable, with little consensus among experts for adults-and even more so for children. To date, pipeline stents have been deployed in 11 pediatric patients, ages 4-15. A variety of clopidogrel and aspirin dosing regimens have been used, with response tested in only three patients, who were all therapeutic. Thrombotic events occurred in two patients, neither of whom were tested. CASE: We describe here the first case of a hemorrhagic complication in a hyper-responsive pediatric patient undergoing placement of a pipeline stent. DISCUSSION: As the use of endovascular therapies requiring dual anti-platelet agents becomes more established, there is an increasing need to develop titration protocols that minimizes the risk of thrombotic and hemorrhagic events.

Endovascular treatment of patients with intracranial stenosis with moyamoya-type collaterals.

PURPOSE: The authors report the endovascular treatment of intracranial stenosis in six patients with moyamoya-type collaterals. PATIENTS: All patients previously had experienced a stroke or transient ischemic attack. Lesion locations included a unilateral M1-segment lesion in five patients; and ipsilateral internal carotid artery (ICA)-T, M1 and A1 lesions with contralateral supraclinoid ICA stenosis in one patient. Mean M1 stenosis was 77.3 ± 14.3%. RESULTS: Six patients had balloon angioplasty; in one, a Wingspan stent deployed successfully after angioplasty failed to relieve the stenosis. Mean post-treatment stenosis was 41.0 ± 33.0%. In one patient, vessel rupture occurring during angioplasty caused severe disability. Two patients were asymptomatic for 4 years and 6 months, respectively. One asymptomatic patient had severe restenosis re-treated with intracranial stenting. Two patients became symptomatic and had re-treatment at 1 and 2 months, respectively. CONCLUSION: Endovascular treatment of intracranial stenosis with moyamoya-type collaterals is possible but is associated with high rates of symptomatic restenosis and target-lesion revascularization.

Salvage Neuroform stent-assisted coiling for recurrent giant aneurysm after waffle-cone treatment.

We report a case of aneurysm progression after waffle-cone treatment. A patient in their seventies presented with headaches. Four years earlier, this individual had undergone waffle-cone treatment of a giant ruptured left ophthalmic aneurysm. Angiography demonstrated aneurysm growth. A second stent was deployed through the initially placed stent to recreate the aneurysm neck and to provide support for stent-assisted coiling. The residual aneurysm was coiled with good outcome.

Stent-assisted basilar reconstruction for a traumatic vertebral dissection with a large basilar artery thrombosis.

An individual in their 30s presented with quadriplegia and coma 7 h after a 30-foot free-fall. Angiography confirmed left vertebral artery dissection causing vertebral artery occlusion (thrombolysis in myocardial infarction (TIMI) 0) and basilar artery thrombosis. Deployment of six self-expanding intracranial stents (right P1 to left V3) resulted in recanalization (TIMI 3). Postoperative MRI demonstrated a large brainstem infarction; the patient was 'locked-in'. In the following 6 months, the patient recovered to ambulation and independence. Aggressive recanalization for symptomatic vertebrobasilar dissection/occlusion may be considered. Despite major diffusion-weighted imaging brainstem lesions, recovery is possible.

Use of the outreach distal access catheter as an intracranial platform facilitates coil embolization of select intracranial aneurysms: technical note.

OBJECTIVE: The Outreach distal access catheter (DAC; Concentric Medical, Mountain View, California, USA) has been designed to assist the Merci device (Concentric Medical) with clot retrieval in the setting of acute stroke. Its application for coil embolization of intracranial aneurysms was investigated. METHODS: Between December 2008 and January 2010, 150 aneurysms were treated with endovascular methods. In 18 cases of small aneurysms and/or increased parent vessel tortuosity, the DAC was used for additional support. Merits and complications related to the use of this catheter are reviewed. RESULTS: The mean aneurysm size was 7.1 mm (range 3.5-25). In each case, the DAC was used as an intracranial platform catheter in close proximity to the target aneurysm. This catheter (outer diameter 3.9 or 4.3 French) increased the stability and reduced the redundancy of the microcatheter. As a result, handling and control of the microcatheter were improved. In three cases, the coiling procedure could not be completed because of difficulties not related to the DAC. Aneurysms in the remaining patients were treated successfully with complete (n=12) or near complete (n=3) angiographic occlusion. CONCLUSION: For smaller or distal intracranial aneurysms with difficult access, use of the DAC as an additional platform in close proximity to the target aneurysm subjectively enhanced microcatheter control and safety.

Complete preoperative embolization of hemangioblastoma vessels with Onyx 18.

The authors present a preliminary experience with ethyl-enevinylalcohol copolymer (Onyx) for hemangioblastoma vessel embolization before surgical resection. The patient presented with neck pain, dizziness, blurred vision, vomiting, and loss of balance. Diagnostic imaging revealed a posterior fossa cystic mass with a nodular component. Angiography demonstrated a significant vascular blush with arteriovenous shunting that was characteristic of a hemangioblastoma. Tumor vessels originating off the left posterior inferior cerebellar artery were embolized before surgery using Onyx 18 (ev3, Covidien Vascular Therapies, Mansfield, MA, USA). This resulted in complete obliteration of all tumor vessels, transforming a highly vascular tumor into an avascular mass. A safe and uneventful surgical resection was performed the next day. Onyx is a valuable embolic agent for preoperative hemangioblastoma vessel embolization. Because of its low viscosity, Onyx penetrates deeply into the tumor vasculature and allows complete obliteration of tumor vessels. Risks of the intervention have to be carefully weighed against the benefits. If preoperative embolization is indicated, the use of Onyx should be strongly considered.

Retrograde trans-posterior communicating artery snare-assisted rescue of lost access to a foreshortened pipeline embolization device: complication management.

BACKGROUND AND IMPORTANCE: The Pipeline embolization device (PED; Covidien Vascular Therapies, Mansfield, Massachusetts) is a promising, yet experimental, vascular reconstruction device for the treatment of complex intracranial aneurysms. We present a PED-related complication and describe a salvage strategy. CLINICAL PRESENTATION: A 64-year-old woman underwent PED-assisted parent vessel reconstruction for her giant cavernous internal carotid artery (ICA) aneurysm. During placement of the first PED, the proximal part of the PED foreshortened and was displaced into the aneurysm sac. Multiple subsequent attempts to recatheterize the PED failed, and, ultimately, distal access through and beyond the PED was lost. Therefore, completion of the Pipeline construct by stacking PEDs for definitive treatment was prevented. Retrograde access of the PED was gained from the distal ICA through a microwire that was advanced from the basilar artery through the posterior communicating artery. The microwire from the distal ICA was grasped with a snare from the proximal ICA and pulled down to the cervical ICA. The opened snare around the microwire was used as a lasso to advance a microcatheter from the cervical ICA through the PED to regain distal access. Five more PEDs were used to achieve complete parent vessel reconstruction and aneurysm obliteration. CONCLUSION: Maintaining distal access is critical until the entire parent vessel is reconstructed, especially when multiple PEDs are required. The salvage technique described may help regain distal access if it is lost during the procedure.

Size ratio correlates with intracranial aneurysm rupture status: a prospective study.

BACKGROUND AND PURPOSE: The prediction of intracranial aneurysm (IA) rupture risk has generated significant controversy. The findings of the International Study of Unruptured Intracranial Aneurysms (ISUIA) that small anterior circulation aneurysms (<7 mm) have a 0% risk of subarachnoid hemorrhage in 5 years is difficult to reconcile with other studies that reported a significant portion of ruptured IAs are small. These discrepancies have led to the search for better aneurysm parameters to predict rupture. We previously reported that size ratio (SR), IA size divided by parent vessel diameter, correlated strongly with IA rupture status (ruptured versus unruptured). These data were all collected retrospectively off 3-dimensional angiographic images. Therefore, we performed a blinded prospective collection and evaluation of SR data from 2-dimensional angiographic images for a consecutive series of patients with ruptured and unruptured IAs. METHODS: We prospectively enrolled 40 consecutive patients presenting to a single institution with either ruptured IA or for first-time evaluation of an incidental IA. Blinded technologists acquired all measurements from 2-dimensional angiographic images. Aneurysm rupture status, location, IA maximum size, and parent vessel diameter were documented. The SR was calculated by dividing the aneurysm size (mm) by the average parent vessel size (mm). A 2-tailed Mann-Whitney test was performed to assess statistical significance between ruptured and unruptured groups. Fisher exact test was used to compare medical comorbidities between the ruptured and unruptured groups. Significant differences between the 2 groups were subsequently tested with logistic regression. SE and probability values are reported. RESULTS: Forty consecutive patients with 24 unruptured and 16 ruptured aneurysms met the inclusion criteria. No significant differences were found in age, gender, smoking status, or medical comorbidities between ruptured and unruptured groups. The average maximum size of the unruptured IAs (6.18 + or - 0.60 mm) was significantly smaller compared with the ruptured IAs (7.91 + or - 0.47 mm; P=0.03), and the unruptured group had significantly smaller SRs (2.57 + or - 0.24 mm) compared with the ruptured group (4.08 + or - 0.54 mm; P<0.01). Logistic regression was used to evaluate the independent predictive value of those variables that achieved significance in univariate analysis (IA maximum size and SR). Using stepwise selection, only SR remained in the final predictive model (OR, 2.12; 95% CI, 1.09 to 4.13). CONCLUSIONS: SR, the ratio between aneurysm size and parent artery diameter, can be easily calculated from 2-dimensional angiograms and correlates with IA rupture status on presentation in a blinded analysis. SR should be further studied in a large prospective observational cohort to predict true IA risk of rupture.

The presigmoid approach to anterolateral pontine cavernomas. Clinical article.

OBJECT: Anterolateral cavernomas of the pons have been surgically removed via a variety of approaches, commonly retrosigmoid or transventricular. The goal in this study was to evaluate the presigmoid approach as an alternative. METHODS: Clinical data were reviewed in 9 patients presenting with anterolateral pontine cavernomas between 1999 and 2007. RESULTS: All patients were treated via a presigmoid approach, which provided a nearly perpendicular trajectory to the anterolateral pons. The brainstem was entered through a "safe zone" between the trigeminal nerve and the facial/vestibulocochlear nerve complex. Complete resection was achieved in all cases. No patient experienced recurrent events during follow-up (1-24 months). The patients' modified Rankin Scale score improved within 1 year of surgery (1.7 ± 0.4) compared with baseline (2.6 ± 0.2; p < 0.05). Only one patient experienced a new deficit (decreased hearing), which was corrected with a hearing aid. CONCLUSIONS: The presigmoid approach is recommended for the resection of anterolateral pontine cavernomas. With this approach, the need for cerebellar retraction is nearly eliminated. The lateral "presigmoid" entry point creates a trajectory that allows complete resection of even deep lesions at this level, or anterior to the internal acoustic meatus.

The small "surgical aneurysm" at the basilar apex.

OBJECT: Because the risks are reduced, larger basilar apex aneurysms are usually treated endovascularly instead of with surgery. However, small basilar apex aneurysms are more common and an unfavorable shape may prevent definitive endovascular treatment. The goal of this study was to reevaluate the outcome of traditional surgery for small unruptured basilar apex aneurysms as an alternative to the currently more accepted endovascular treatment. METHODS: The authors reviewed clinical data obtained in 21 patients who underwent surgery between 2000 and 2007 for unruptured basilar apex aneurysms < 7 mm. RESULTS: The median age of the 21 patients was 52 years (range 29-74 years). All patients experienced a good outcome. Two patients harbored a small residual aneurysm (> 95% occlusion). Eight patients (38%) suffered a temporary third nerve paresis, which resolved in all cases. CONCLUSIONS: Surgical clip ligation remains an excellent treatment for small basilar apex aneurysms. The treatment is definitive and in experienced hands is associated with a low risk.

The balloon anchor technique: a novel technique for distal access through a giant aneurysm.

A novel technique is reported that helps the operator in achieving reliable access to the distal parent vessel with a microcatheter for stent assisted aneurysm coiling. Distal parent vessel access was obtained by allowing the microwire to follow the local hemodynamics into a giant internal carotid artery aneurysm and around its dome. Various traditional methods were tried before attempting the balloon anchor. In this technique, an over-the-wire balloon was inflated in the distal vessel followed by gentle retraction of the balloon catheter and microwire allowed only a wire bridge across the aneurysm neck, thereby allowing the stent catheter to be brought up in a standard fashion. This technique may facilitate the use of new stent technologies for the treatment of aneurysms that would otherwise be untreatable with endovascular therapies.

A1-A2 interposition grafting for surgical treatment of a giant "unclippable" A1 segment aneurysm.

BACKGROUND: Although various bypass options for the surgical treatment of middle cerebral artery aneurysms have been described, little has been reported about similar options for complex aneurysms of the anterior cerebral artery. CASE DESCRIPTION: We report the case of a 15-year-old adolescent girl, in whom a giant A1 segment aneurysm was successfully treated with aneurysm resection followed by saphenous vein interposition grafting. CONCLUSION: Recognizing the option for a bypass can be the key to success in the surgical management of complex intracranial aneurysms. A potential donor vessel of appropriate size (either arterial or venous) should be prospectively identified. Interposition grafting is technically feasible for proximal anterior cerebral artery aneurysms, although technically demanding.

Stent/coil treatment of very large and giant unruptured ophthalmic and cavernous aneurysms.

BACKGROUND: Treatment of VLGUIA remains a challenge. To reduce mass effect and achieve complete occlusion, open surgery has been our favored treatment. However, endovascular therapy is preferred for lesions in the cavernous sinus or for older patients with complicating medical problems. The goal of this study is to investigate outcome of stent and/or coil treatment of VLGUIA. METHODS: Beginning in 2002, the neuroform stent has been available to the University of Texas Southwestern Medical Center in Dallas. Since then until 2006, 15 patients were treated for VLGUIA with stenting and/or coiling at this institution. These 15 patients were used for a retrospective analysis in this study. RESULTS: Median patient age was 65 years, median aneurysm size was 27 mm (20-37 mm), and median follow-up time was 22 months. Eight aneurysms were localized in the cavernous sinus and 7 at the ophthalmic segment of the internal carotid artery. Four aneurysms were completely occluded (100%); 3 aneurysms, nearly complete (90%-99%); and 8 aneurysms, partial (<90% occlusion). Twelve patients required retreatment. Final GOS was 1 (good recovery) in 11 patients, 2 (moderate disability) in 3 patients, and 3 (severely disabled) in 1 patient. No patient died or deteriorated. CONCLUSIONS: Stent/coil management of VLGUIA is constantly evolving. Current treatment results are promising, with very low morbidity/mortality. Disadvantage is the frequent persistence of residual aneurysm.

Symptomatic brainstem cavernomas.

OBJECTIVE: The goal of this study was to analyze the natural history of symptomatic brainstem cavernomas (medulla, pons, or midbrain) and outcome after surgical resection. METHODS: We retrospectively analyzed clinical data of all patients who presented to our institution with symptomatic brainstem cavernomas between 1995 and 2007 (n = 44). RESULTS: After a first neurological event, the median event-free interval was 2 years, with an annual event rate of 42%. After a second neurological event (new neurological deficit or significant worsening of the previous deficit), the median event-free interval was only 5 months, with a monthly event rate of 8%. After an observation period of up to 8 years, all patients ultimately underwent surgery. In 95% of the patients, surgery successfully prevented further events during a median follow-up period of 11 months (1 month-7 years; P < 0.001). The postoperative event rate was 5% per year in the first 2 years and 0% thereafter. In the multivariate analysis, only the preoperative modified Rankin scale score was predictive of the surgical outcome (odds ratio, 36.7; P = 0.015). The conditions of 2 patients (5%) were clinically worse compared with their preoperative conditions during the 1-year follow-up period; in one of these patients, this was caused by recurrent events. There was no mortality. CONCLUSION: The event rate of symptomatic lesions seems to be high, particularly after recurrent events. Surgical morbidity can be low. Timely and complete surgical resection is recommended for symptomatic brainstem cavernomas to prevent patients' functional decline owing to recurrent events.

Clipping of very large or giant unruptured intracranial aneurysms in the anterior circulation: an outcome study.

OBJECT: Patients with very large or giant unruptured intracranial aneurysms present with ischemic stroke and progressive disability. The aneurysm rupture risk in these patients is extreme-up to 50% in 5 years. In this study the authors investigated the outcome of surgical treatment for these very large aneurysms in the anterior circulation. METHODS Clinical data on 62 patients who underwent surgery for unruptured aneurysms (20-60 mm) between 1998 and 2006 were reviewed. RESULTS: Complete aneurysm occlusion (100%) was achieved in 90% of cases, near complete occlusion (90-99%) in 5%. The surgical risk in patients younger than 50 years of age was 8% (Glasgow Outcome Scale score of 1 or 3 within 1 year after surgery). In older patients, the risk increased with advancing age. CONCLUSIONS: The treatment of very large or giant unruptured intracranial aneurysms is hazardous and complex and thus best performed only at major cerebrovascular centers with an experienced team of neurosurgeons, interventional neuroradiologists, neurologists, and neuroanesthesiologists. Surgery, with acceptable risks and excellent occlusion rates, is typically the treatment of choice in patients younger than 50 years of age. In older patients, the benefits of endovascular treatment versus surgery versus no treatment must be carefully weighed individually. Minimizing temporary occlusion and the consequent use of intraoperative angiography may help reduce surgical complications.

Intraventricular ganglioglioma.

Gangliogliomas are mixed tumors consisting of both glial elements and differentiated neurons. Although any part of the central nervous system can be affected, little is known about intraventricular gangliogliomas. A patient with a ganglioglioma is presented in the previously unreported location of the anterior third ventricle at the foramen of Monro, mimicking a colloid cyst. We review all other reported cases of intraventricular ganglioglioma (n=6) to characterize this entity. Intraventricular gangliogliomas typically affect younger patients with female predominance (male:female, 2:5; median age 25 years). Symptoms occur secondary to obstruction of physiological cerebrospinal fluid circulation. Complete surgical resection with re-establishment of cerebrospinal fluid drainage is the goal of treatment.

Cerebral phaeohyphomycosis mimics high-grade astrocytoma.

The incidence of cerebral phaeohyphomycosis, an infection caused by a dark-pigmented fungus, is increasing. The infection may mimic a high-grade glioma clinically and radiographically. Magnetic resonance spectroscopy may be helpful in differentiating the two. We report two cases to increase the awareness of cerebral phaeohyphomycosis in the clinical neurosciences. Early biopsy establishing the diagnosis, followed by aggressive combined surgical and medical management is necessary for a good outcome.