Exposure to topiramate and acetazolamide causes endocrine disrupting effects in female rats during estrus

BACKGROUND

Idiopathic intracranial hypertension (IIH) is a disease characterized by elevated intracranial pressure (ICP) and is a disease of young females. The first line pharmacological treatments include acetazolamide and topiramate and given the nature of IIH patients and the dosing regimen of these drugs, their effect on the endocrine system is important to evaluate. We aimed to assess the effects of acetazolamide and topiramate on steroid profiles in relevant endocrine tissues.

METHODS

Female Sprague Dawley rats received chronic clinically equivalent doses of acetazolamide or topiramate by oral gavage and were sacrificed in estrus. Tissue specific steroid profiles of lateral ventricle CP, 4th ventricle CP, CSF, serum, uterine horn and fundus, ovaries, adrenal glands and pituitary glands were assessed by quantitative targeted LC-MS/MS. We determined luteinizing hormone (LH) and follicle stimulating hormones (FSH) levels in paired serum by ELISA.

RESULTS

Topiramate increased the concentration of estradiol and decreased the concentration of DHEA in lateral choroid plexus. Moreover, it decreased the concentration of androstenediol in the pituitary gland. Topiramate increased serum LH. Acetazolamide decreased progesterone levels in serum and uterine fundus and increased corticosteroid levels in the adrenal glands.

CONCLUSION

These results demonstrate that both acetazolamide and topiramate have endocrine disrupting effects in rats. Topiramate primarily targeted the choroid plexus and the pituitary gland while acetazolamide had broader systemic effects. Furthermore, topiramate predominantly targeted sex hormones, whereas acetazolamide widely affected all classes of hormones. A similar effect in humans has not yet been documented but these concerning findings warrants further investigations.

Redefining treatment expectations: exploring mid- and long-term outcomes of venous sinus stenting in idiopathic intracranial hypertension

BACKGROUND

Venous sinus stenting (VSS) is recognized as a safe and effective intervention for medically-refractory idiopathic intracranial hypertension (IIH). However, its long-term efficacy remains uncertain.

METHODS

This retrospective review analyzed a single-center database of adult patients with severe, medically-refractory IIH, who underwent VSS and had minimum 3-month follow-up (FU). Patients were divided into three groups based on post-stenting symptom trajectories: group 1 (sustained improvement without relapse), group 2 (temporary improvement with relapse), and group 3 (no improvement).

RESULTS

Of 178 patients undergoing VSS, the majority were female (94%), with a median opening pressure (OP) of 31 cm H2O and trans-stenosis gradient of 14 mm Hg. Of these, 153 (86%) received transverse sinus (TS) stenting, and 19 (11%) underwent concurrent TS and superior sagittal sinus stenting. At a mean FU of 166 days, 53 patients (30%) showed long-term improvement without relapse (group 1). Symptomatic recurrence was noted in 101 patients (57%; group 2) within a mean FU of 390 days. Despite recurrent headache and tinnitus, the average OP reduction was 9.6 cm H2O on repeat lumbar puncture, with 75% showing papilledema improvement or resolution post-VSS. Only 17% required further surgical intervention.

CONCLUSIONS

The most common clinical outcome post-VSS in IIH patients is initial symptomatic improvement followed by symptom recurrence in about 60% at a mean of 274 days, despite a consistent intracranial pressure reduction. These findings can guide physicians in setting realistic expectations with patients regarding VSS outcomes.

CT-guided percutaneous cyanoacrylate injection targeting the spinal cerebrospinal fluid leak: a potential therapeutic option for spontaneous intracranial hypotension

BACKGROUND

We report the first case series of spontaneous intracranial hypotension (SIH) patients who underwent CT-guided percutaneous cyanoacrylate injection targeting the cerebrospinal fluid (CSF) leak.

METHODS

A retrospective analysis was performed for all consecutive cases of SIH patients with CSF leak confirmed on CT myelography, treated by CT-guided percutaneous cyanoacrylate injection at our institution from 2016 to 2022. On pretreatment brain and spine MRIs, we analyzed signs of SIH according to the Bern score, and dichotomized cases into positive/negative for spinal longitudinal extradural CSF collection (SLEC-P or SLEC-N). The leaks detected on CT myelography were classified into three types according to Schievink et al. We collected the Headache Impact Test 6 (HIT-6) scores throughout a 6-month follow-up, with a brain CT scan at each visit.

RESULTS

11 patients were included (mean age 48.4 years, six men). Five SLEC-P type 1, three SLEC-P type 2, and three SLEC-N type 3 leaks were identified. All patients had significant signs of SIH on pretreatment brain MRI (mean Bern score 7.8±1.1). Six patients underwent a foraminal puncture, and five patients had a cervical epidural approach. Two patients experienced mild and transient locoregional pain after cervical epidural injection. Mean HIT-6 score at baseline was 66.8±3.2 and at the 6-month follow-up was 38±3.6 (P<0.001). All patients achieved improvement in their symptoms, with 82% of them (9/11) having complete resolution of headaches and SIH findings on CT scans at 6 months. No clinical worsening or recurrence was observed.

CONCLUSIONS

CT-guided percutaneous cyanoacrylate injection may be a potential therapeutic option for the different types of CSF leak causing SIH.

Zilver stent versus Carotid Wallstent for endovascular treatment of idiopathic intracranial hypertension

BACKGROUND

Venous sinus stenting (VSS) is a promising treatment option for medically refractory idiopathic intracranial hypertension (IIH). There are no published studies comparing the performance of different types of stents employed in VSS procedures. In this study we aimed to compare the safety and efficacy outcomes of the Zilver 518 (Cook Medical, Bloomington, Indiana, USA) and the Carotid Wallstent (Boston Scientific, Marlborough, Massachusetts, USA) devices.

METHODS

Records of patients with IIH who underwent VSS between January 2015 and February 2022 at a single referral center were retrospectively reviewed. Patients treated with the Zilver stent or Carotid Wallstent were included in the study. Stent model and size data, pre- and post-treatment pressure gradients, technical and safety outcomes, and pre- and post- stenting papilledema, headache, and tinnitus severity were collected. The χ2 and Fisher-Freeman-Halton tests were used for categorical data and the Student's t-test and Mann-Whitney U test were employed to examine the differences in non-categorical variables.

RESULTS

A total of 81 procedures (28 (34.5%) with the Zilver stent and 53 (65.5%) with the Carotid Wallstent) were performed in 76 patients. The mean procedure time was significantly shorter with the Zilver stent (22.56±10.2 vs 33.9±15 min, p=0.001). The papilledema improvement and resolution rates did not significantly differ between groups (94.7% vs 94.5%, p>0.99 for improvement; 78.9% vs 67.5%, p=0.37 for resolution). The tinnitus improvement and resolution rates in the Zilver stent group were significantly higher than those of the Carotid Wallstent group (100% vs 78.9%, p=0.041; 90% vs 63.1%, p=0.03, respectively). Additionally, the Zilver stent provided a significantly higher rate of headache resolution and improvement than the Carotid Wallstent (84.6% vs 27.6%, p=0.001 for resolution; 92.3% vs 72.3%, p=0.043 for improvement). One patient from the Carotid Wallstent group underwent re-stenting due to in-stent stenosis and refractory papilledema. No significant in-stent stenosis was observed in the Zilver stent group.

CONCLUSION

Stent choice may affect VSS outcomes. The Zilver stent provided better clinical outcomes than the Carotid Wallstent, with significantly shorter procedure times. Larger studies are needed to determine the efficacy of available venous stents for IIH.

Natural history of spontaneous intracranial hypotension: a clinical and imaging study

BACKGROUND

Although spontaneous intracranial hypotension (SIH) is well studied, there are few studies of the clinical and imaging history of SIH without interventional treatments. For example, what is the natural history of those who are untreated or treated only with conservative measures?

OBJECTIVE

To conduct a retrospective study examining changes in imaging findings for patients with SIH without interventional treatments and to study associations between imaging findings and clinical symptoms.

METHODS

Included patients had a clinical diagnosis of SIH, were seen at Mayo Clinic between 1999 and 2021, had a brain MRI scan indicating SIH (Bern score), and had a brain MRI scan 6 or more months later without intervening leak-related interventional treatment. Bern scores were assigned for the first and last MRI scans prior to treatment. Patients were also grouped into three qualitative categories: overall improvement of symptoms, stable symptoms, or worsened symptoms based on patient report during the clinical visit at the time of the follow-up brain MRI scan.

RESULTS

Among 46 patients with untreated SIH, the Bern score improved over time in 11 (24%), was stable in 30 (65%), and worsened in 5 (11%). Two patients (4.3%) showed complete resolution of all abnormalities by the Bern scoring criteria. Symptoms improved in 7 (15%), were stable in 29 (63%), and worsened in 10 (22%).

CONCLUSIONS

In patients with brain MRI evidence of SIH, almost 25% demonstrated radiographic improvement, and 15% reported clinical improvement, during at least 6 months of observation or conservative treatment. Most had stable, persistent MRI abnormalities and symptoms when SIH was untreated.

A descriptive study of venous pressures and gradients while awake and both pre- and post-stent under anesthesia in patients with idiopathic intracranial hypertension

BACKGROUND

This study aims to explore factors that affect venous sinus pressures and associated gradients while awake and under general anesthesia (GA) both before and after venous sinus stenting (VSS) in patients with idiopathic intracranial hypertension (IIH).

METHODS

A retrospective analysis was performed examining pressures and gradients in patients with IIH having undergone awake venography followed by VSS under GA.

RESULTS

174 patients were included. Compared with awake, GA superior sagittal sinus (SSS) pressures were 2.6 mmHg lower (p=0.01) resulting in a total cranial gradient reduction of 2.5 mmHg (p=0.002). The transverse-sigmoid gradient, the most commonly stented segment, did not differ under the two conditions (p=0.30). Regression analyses demonstrated that body mass index, gender, blood pressure, and end-tidal carbon dioxide content significantly affected venous pressures (all p<0.05). After stenting, mean total cranial gradients decreased by 13.2 mmHg while skull base gradients increased by 0.8 mmHg. Stenting resulted in an 84% mean reduction in the target gradient and a mean decrease in SSS pressures by 78% of the target gradient. When cardiopulmonary and anesthetic factors were optimized, GA had a limited effect on the target gradient in most patients (p=0.88).

CONCLUSIONS

This study is the largest series to date to report on cerebral venous pressure measurements and gradients recorded while awake and under GA both before and after VSS for IIH. In a well-controlled cardiorespiratory and anesthetic setting, GA venography may provide information that is not substantially inequivalent to that obtained while awake.

An Audit of Tracheostomy in Traumatic Brain Injury

INTRODUCTION

The timing of tracheostomy in traumatic brain injury is controversial. The benefits of early tracheostomy are early weaning from ventilation, and reduction in pneumonia. But some studies demonstrated increase in intracranial pressure during tracheostomy.

AIM AND METHODS

The aims of the audit are to analyse the timing, benefits, complications, and the results of tracheostomy in patients with traumatic brain injury in the hospital in the period of 2012-2021.

RESULTS

The number of patients was 34. The maximum number of tracheostomies(24) were between 6th to 14th days of admission. The complications were: worsening of Glasgow coma scale score - 3 (in the early group), bleeding - 2, subglottic stenosis-1, tracheocutaneous fistula-1. The main benefits obtained form tracheostomy were the easiness of weaning and tracheobronchial toilet. Twelve patients had pneumonia. Nine patients survived out of twelve. Six patients had acute respiratory distress syndrome. Five of them succumbed. The weaning time corresponded to the severity of injury and pulmonary status. The mortality according to the timing of tracheostomy were: 1/6(16.67%) in the group of first week, 9/19(47%) in the group of second week, and 3/8(37.5%) in the group of the third and fourth week. The mortality was less in the group of first week.

CONCLUSIONS

The timing of tracheostomy in traumatic brain injury should be at the earliest after the control of raised intracranial tension. There was reversible worsening of Glasgow coma scale score for 2 points in 3 cases after early tracheostomy. Mortality was less in the group of early tracheostomy.

In vivo Modulation of Intraocular and Intracranial Pressures Causes Nonlinear and Non-monotonic Deformations of the Lamina Cribrosa and Scleral Canal

Purpose

To evaluate changes in monkey optic nerve head (ONH) morphology under acutely controlled intraocular pressure (IOP) and intracranial pressure (ICP).

Methods

Seven ONHs from six monkeys were imaged via optical coherence tomography while IOP and ICP were maintained at one of 16 conditions. These conditions were defined by 4 levels for each pressure: low, baseline, high and very high. Images were processed to determine scleral canal area, aspect ratio, and planarity and anterior lamina cribrosa (ALC) shape index and curvature. Linear mixed effect models were utilized to investigate the effects of IOP, ICP and their interactions on ONH morphological features. The IOP-ICP interaction model was compared with one based on translaminar pressure difference (TLPD).

Results

We observed complex, eye-specific, non-linear patterns of ONH morphological changes with changes in IOP and ICP. For all ONH morphological features, linear mixed effects models demonstrated significant interactions between IOP and ICP that were unaccounted for by TLPD. Interactions indicate that the effects of IOP and ICP depend on the other pressure. The IOP-ICP interaction model was a higher quality predictor of ONH features than a TLPD model.

Conclusions

In vivo modulation of IOP and ICP causes nonlinear and non-monotonic changes in monkey ONH morphology that depend on both pressures and is not accounted for by a simplistic TLPD. These results support and extend prior findings.

Translational Relevance

A better understanding of ICP's influence on the effects of IOP can help inform the highly variable presentations of glaucoma and effective treatment strategies.

Cerebral venous anatomy: implications for the neurointerventionalist

Meaningful contributions to neurointerventional practice may be possible by considering the dynamic aspects of angiography in addition to fixed morphologic information. The functional approach to venous anatomy requires integration of the traditional static anatomic features of the system-deep, superficial, posterior fossa, medullary veins, venous sinuses, and outflow routes into an overall appreciation of how a classic model of drainage is altered, embryologically, or pathologically, depending on patterns of flow-visualization made possible by angiography. In this review, emphasis is placed on balance between alternative venous networks and their redundancy, and the problems which arise when these systems are lacking. The role of veins in major neurovascular diseases, such as dural arteriovenous fistulae, arteriovenous malformations, pulsatile tinnitus, and intracranial hypertension, is highlighted, and deficiencies in knowledge emphasized.

Cisternostomy for malignant middle cerebral artery infarction: proposed pathophysiological mechanisms and preliminary results

BACKGROUND

The ischaemic stroke of the territory of the middle cerebral artery represents an event burdened by high mortality and severe morbidity. The proposed medical treatments do not always prove effective. Decompressive craniectomy allows the ischaemic tissue to shift through the surgical defect rather than to the unaffected regions of the brain, thus avoiding secondary damage due to increased intracranial pressure. In this study, we propose a novel treatment for these patients characterised by surgical fenestration of the cisterns of the skull base.

METHODS

We have treated 16 patients affected by malignant middle cerebral artery ischaemia and treated with cisternostomy between August 2018 and December 2019. The clinical history, neurological examination findings and neuroradiological studies (brain CT, CT angiography, MRI) were performed to diagnose stroke. Clinical examination was recorded on admission and preoperatively using the Glasgow Coma Scale and the National Institutes of Health Stroke Scale.

RESULTS

The study included 16 patients, 10 males and 6 females. The mean age at surgery was 60.1 years (range 19-73). Surgical procedure was performed in all patients. The patients underwent immediate postoperative CT scan and were in the early hours evaluated in sedation window. In total, we recorded two deaths (12.5%). A functional outcome between mRS 0-3, defined as favourable, was observed in 9 (64.2%) patients 9 months after discharge. A functional outcome between mRS 4-6, defined as poor, was observed in 5 (35.7%) patients 9 months after discharge.

CONCLUSIONS

The obtained clinical results appear, however, substantially overlapping to decompressive craniectomy. Cisternostomy results in a favourable functional outcome after 9 months. This proposed technique permits that the patient no longer should be undergone cranioplasty thus avoiding the possible complications related to this procedure. The results are certainly interesting but higher case numbers are needed to reach definitive conclusions.

Decompressive craniectomy combined with temporal pole resection in the treatment of massive cerebral infarction

OBJECTIVE

To evaluate the efficacy and prognosis of decompressive craniectomy combined with temporal pole resection in the treatment of massive cerebral infarction, in order to provide basis for treatment selection.

METHODS

The clinical data of the patient with massive cerebral infarction treated in our hospital from January 2015 to December 2018 were analyzed retrospectively. According to the surgical methods, the patients were divided into control group (decompressive craniectomy) and study group (decompressive craniectomy + temporal pole resection). Intracranial pressure monitoring devices were placed in both groups. The NIHSS scores of the two groups before and 14 days after operation, the changes of intracranial pressure, length of hospital stay, length of NICU, mortality and modified Rankin scale before and after treatment were compared between the two groups.

RESULTS

The NIHSS score of the two groups after operation was lower than that before operation, and the NIHSS score of the study group was significantly lower than that of the control group (P < 0.05); The intracranial pressure in the study group was significantly lower than that in the control group (P < 0.05); One month after operation, the mortality of the study group (13.0%) was lower than that of the control group (27.8%). After one year of follow-up, the mortality of the study group (21.7%) was significantly lower than that of the control group (38.8%) (P < 0.05); The scores of mRS in the two groups were significantly improved compared with those before treatment (P < 0.05), and the scores of mRS in the study group were better than those in the control group (P < 0.05).

CONCLUSION

Decompressive craniectomy combined with temporal pole resection has a better effect in the treatment of patients with massive cerebral infarction. It has good decompression effect, the postoperative intracranial pressure is well controlled, and significantly reduced the mortality. So it has better clinical application value.

Comparing the Efficiency of Two Treatment Methods of Hydrocephalus: Shunt Implantation and Endoscopic Third Ventriculostomy

Introduction:

Hydrocephalus is one of the most common diseases in children, and its treatment requires brain operation. However, the pathophysiology of the disease is very complicated and still unknown.

Methods:

Endoscopic Third Ventriculostomy (ETV) and Ventriculoperitoneal Shunt (VPS) implantation are among the common treatments of hydrocephalus. In this study, Cerebrospinal Fluid (CSF) hydrodynamic parameters and efficiency of the treatment methods were compared with numerical simulation and clinical follow-up of the treated patients.

Results:

Studies have shown that in patients under 19 years of age suffering from hydrocephalus related to a Posterior Fossa Brain Tumor (PFBT), the cumulative failure rate was 21% and 29% in ETV and VPS operation, respectively. At first, the ETV survival curve shows a sharp decrease and after two months it gets fixed while VPS curve makes a gradual decrease and reaches to a level lower than ETV curve after 5.7 months. Post-operative complications in ETV and VPS methods are 17% and 31%, respectively. In infants younger than 12 months with hydrocephalus due to congenital Aqueduct Stenosis (AS), and also in the elderly patients suffering from Normal Pressure Hydrocephalus (NPH), ETV is a better treatment option. Computer simulations show that the maximum CSF pressure is the most reliable hydrodynamic index for the evaluation of the treatment efficacy in these patients. After treatment by ETV and shunt methods, CSF pressure decreases about 9 and 5.3 times, respectively and 2.5 years after shunt implantation, this number returns to normal range.

Conclusion:

In infants with hydrocephalus, initial treatment by ETV was more reasonable than implanting the shunt. In adult with hydrocephalus, the initial failure in ETV occurred sooner compared to shunt therapy; however, ETV was more efficient.

Lower body negative pressure to safely reduce intracranial pressure

KEY POINTS

During long-term missions, some astronauts experience structural and functional changes of the eyes and brain which resemble signs/symptoms experienced by patients with intracranial hypertension. Weightlessness prevents the normal cerebral volume and pressure 'unloading' associated with upright postures on Earth, which may be part of the cerebral and ocular pathophysiology. By placing the lower body in a negative pressure device (LBNP) that pulls fluid away from cranial compartments, we simulated effects of gravity and significantly lowered pressure within the brain parenchyma and ventricle compartments. Application of incremental LBNP demonstrated a non-linear dose-response curve, suggesting 20 mmHg LBNP as the optimal level for reducing pressure in the brain without impairing cerebral perfusion pressure. This non-invasive method of reducing pressure in the brain holds potential as a countermeasure in space as well as having treatment potential for patients on Earth with traumatic brain injury or other pathology leading to intracranial hypertension.

ABSTRACT

Patients with elevated intracranial pressure (ICP) exhibit neuro-ocular symptoms including headache, papilloedema and loss of vision. Some of these symptoms are also present in astronauts during and after prolonged space-flight where lack of gravitational stress prevents daily lowering of ICP associated with upright posture. Lower body negative pressure (LBNP) simulates the effects of gravity by displacing fluid caudally and we hypothesized that LBNP would lower ICP without compromising cerebral perfusion. Ten cerebrally intact volunteers were included: six ambulatory neurosurgical patients with parenchymal ICP-sensors and four former cancer patients with Ommaya-reservoirs to the frontal horn of a lateral ventricle. We applied LBNP while recording ICP and blood pressure while supine, and during simulated intracranial hypertension by 15° head-down tilt. LBNP from 0 to 50 mmHg at increments of 10 mmHg lowered ICP in a non-linear dose-dependent fashion; when supine (n = 10), ICP was decreased from 15 ± 2 mmHg to 14 ± 4, 12 ± 5, 11 ± 4, 10 ± 3 and 9 ± 4 mmHg, respectively (P < 0.0001). Cerebral perfusion pressure (CPP), calculated as mean arterial blood pressure at midbrain level minus ICP, was unchanged (from 70 ± 12 mmHg to 67 ± 9, 69 ± 10, 70 ± 12, 72 ± 13 and 74 ± 15 mmHg; P = 0.02). A 15° head-down tilt (n = 6) increased ICP to 26 ± 4 mmHg, while application of LBNP lowered ICP (to 21 ± 4, 20 ± 4, 18 ± 4, 17 ± 4 and 17 ± 4 mmHg; P < 0.0001) and increased CPP (P < 0.01). An LBNP of 20 mmHg may be the optimal level to lower ICP without impairing CPP to counteract spaceflight-associated neuro-ocular syndrome in astronauts. Furthermore, LBNP holds clinical potential as a safe, non-invasive method for lowering ICP and improving CPP for patients with pathologically elevated ICP on Earth.

An Integration of Decision Tree and Visual Analysis to Analyze Intracranial Pressure

In Traumatic Brain Injury (TBI), elevated Intracranial Pressure (ICP) causes severe brain damages due to hemorrhage and swelling. Monitoring ICP plays an important role in the treatment of TBI patients because ICP is considered a strong predictor of neurological outcome and a potentially amenable method to treat patients. However, it is difficult to predict and measure accurate ICP due to the complex nature of patients' clinical conditions. ICP monitoring for severe TBI patient is a challenging problem for clinicians because traditionally known ICP monitoring is an invasive procedure by placing a device inside the brain to measure pressure. Therefore, ICP monitoring might have a high infection risk and cause medical complications. In here, an ICP monitoring using texture features is proposed to overcome this limitation. The combination of image processing methods and a decision tree algorithm is utilized to estimate ICP of TBI patients noninvasively. In addition, a visual analytics tool is used to conduct an interactive visual factor analysis and outlier detection.

Current management of spontaneous intracerebral haemorrhage

Intracerebral haemorrhage (ICH) is the most devastating and disabling type of stroke. Uncontrolled hypertension (HTN) is the most common cause of spontaneous ICH. Recent advances in neuroimaging, organised stroke care, dedicated Neuro-ICUs, medical and surgical management have improved the management of ICH. Early airway protection, control of malignant HTN, urgent reversal of coagulopathy and surgical intervention may increase the chance of survival for patients with severe ICH. Intensive lowering of systolic blood pressure to <140 mm Hg is proven safe by two recent randomised trials. Transfusion of platelets in patients on antiplatelet therapy is not indicated unless the patient is scheduled for surgical evacuation of haematoma. In patients with small haematoma without significant mass effect, there is no indication for routine use of mannitol or hypertonic saline (HTS). However, for patients with large ICH (volume > 30 cbic centmetre) or symptomatic perihaematoma oedema, it may be beneficial to keep serum sodium level at 140–150 mEq/L for 7–10 days to minimise oedema expansion and mass effect. Mannitol and HTS can be used emergently for worsening cerebral oedema, elevated intracranial pressure (ICP) or pending herniation. HTS should be administered via central line as continuous infusion (3%) or bolus (23.4%). Ventriculostomy is indicated for patients with severe intraventricular haemorrhage, hydrocephalus or elevated ICP. Patients with large cerebellar or temporal ICH may benefit from emergent haematoma evacuation. It is important to start intermittent pneumatic compression devices at the time of admission and subcutaneous unfractionated heparin in stable patients within 48 hours of admission for prophylaxis of venous thromboembolism. There is no benefit for seizure prophylaxis or aggressive management of fever or hyperglycaemia. Early aggressive comprehensive care may improve survival and functional recovery.

Moving target: transient rotational stenosis precipitating jugular bow hunter's syndrome

A 60-year-old man presented with a 10-month history of of stereotypical spells characterized by vertigo, tinnitus, blurred vision, left hemibody numbness, and occasional syncope, precipitated by turning his head leftwards. Cerebral angiography and CT angiography of the head and neck with provocative maneuvers did not demonstrate vertebral artery narrowing. However, there was narrowing of the left internal jugular vein due to extrinsic compression from the sternocleidomastoid with leftward head rotation in the setting of hypoplasia of the right internal jugular vein. The patient underwent a cervical venogram which confirmed the finding. Manometric evaluation demonstrated a gradient of 29 mm Hg across the stenosis with the head turned leftwards compared with 1 mm Hg in the neutral position. The patient was treated with myectomies of the left sternocleidomastoid, posterior belly of the digastric, stylohyoid and omohyoid and styloid process removal. Following surgery, the patient reported complete resolution of symptoms. Repeat venography demonstrated resolution of the stenosis and pressure gradient.

Intra-arterial nitroglycerin as directed acute treatment in experimental ischemic stroke

BACKGROUND

Nitroglycerin (also known as glyceryl trinitrate (GTN)), a vasodilator best known for treatment of ischemic heart disease, has also been investigated for its potential therapeutic benefit in ischemic stroke. The completed Efficacy of Nitric Oxide in Stroke trial suggested that GTN has therapeutic benefit with acute (within 6 hours) transdermal systemic sustained release therapy.

OBJECTIVE

To examine an alternative use of GTN as an acute therapy for ischemic stroke following successful recanalization.

METHODS

We administered GTN IA following transient middle cerebral artery occlusion in mice. Because no standard dose of GTN is available following emergent large vessel occlusion, we performed a dose-response (3.12, 6.25, 12.5, and 25 µg/µL) analysis. Next, we looked at blood perfusion (flow) through the middle cerebral artery using laser Doppler flowmetry. Functional outcomes, including forced motor movement rotor rod, were assessed in the 3.12, 6.25, and 12.5 µg/µL groups. Histological analysis was performed using cresyl violet for infarct volume, and glial fibrillary activating protein (GFAP) and NeuN immunohistochemistry for astrocyte activation and mature neuron survival, respectively.

RESULTS

Overall, we found that acute post-stroke IA GTN had little effect on vessel dilatation after 15 min. Functional analysis showed a significant difference between GTN (3.12 and 6.25 µg/µL) and control at post-stroke day 1. Histological measures showed a significant reduction in infarct volume and GFAP immunoreactivity and a significant increase in NeuN.

CONCLUSIONS

These results demonstrate that acute IA GTN is neuroprotective in experimental ischemic stroke and warrants further study as a potentially new stroke therapy.

Moving target: transient rotational stenosis precipitating jugular bow hunter's syndrome

A 60-year-old man presented with a 10-month history of of stereotypical spells characterized by vertigo, tinnitus, blurred vision, left hemibody numbness, and occasional syncope, precipitated by turning his head leftwards. Cerebral angiography and CT angiography of the head and neck with provocative maneuvers did not demonstrate vertebral artery narrowing. However, there was narrowing of the left internal jugular vein due to extrinsic compression from the sternocleidomastoid with leftward head rotation in the setting of hypoplasia of the right internal jugular vein. The patient underwent a cervical venogram which confirmed the finding. Manometric evaluation demonstrated a gradient of 29 mm Hg across the stenosis with the head turned leftwards compared with 1 mm Hg in the neutral position. The patient was treated with myectomies of the left sternocleidomastoid, posterior belly of the digastric, stylohyoid and omohyoid and styloid process removal. Following surgery, the patient reported complete resolution of symptoms. Repeat venography demonstrated resolution of the stenosis and pressure gradient.

Aqueous Date Fruit Efficiency as Preventing Traumatic Brain Deterioration and Improving Pathological Parameters after Traumatic Brain Injury in Male Rats

Objective

Following traumatic brain injury, disruption of blood-brain-barrier and consequent brain edema are critical events which might lead to increasing intracranial pressure (ICP), and nerve damage. The current study assessed the effects of aqueous date fruit extract (ADFE) on the aforementioned parameters.

Materials and Methods

In this experimental study, diffused traumatic brain injury (TBI) was generated in adult male rats using Marmarou’s method. Experimental groups include two pre-treatment (oral ADFE, 4 and 8 mL/kg for 14 days), vehicle (distilled water, for 14 days) and sham groups. Brain edema and neuronal injury were measured 72 hours after TBI. Veterinary coma scale (VCS) and ICP were determined at -1, 4, 24, 48 and 72 hours after TBI. Differences among multiple groups were assessed using ANOVA. Turkey’s test was employed for the ANOVA post-hoc analysis. The criterion of statistical significance was sign at P<0.05.

Results

Brain water content in ADFE-treated groups was decreased in comparison with the TBI+vehicle group. VCS at 24, 48 and 72 hours after TBI showed a significant increase in ADFE groups in comparison with the TBI+vehicle group. ICP at 24, 48 and 72 hours after TBI, was decreased in ADFE groups, compared to the TBI+vehicle. Brain edema, ICP and neuronal injury were also decreased in ADFE group, but VCS was increased following on TBI.

Conclusion

ADFE pre-treatment demonstrated an efficient method for preventing traumatic brain deterioration and improving pathological parameters after TBI.

Investigating cerebral oedema using poroelasticity

Cerebral oedema can be classified as the tangible swelling produced by expansion of the interstitial fluid volume. Hydrocephalus can be succinctly described as the abnormal accumulation of cerebrospinal fluid (CSF) within the brain which ultimately leads to oedema within specific sites of parenchymal tissue. Using hydrocephalus as a test bed, one is able to account for the necessary mechanisms involved in the interaction between oedema formation and cerebral fluid production, transport and drainage. The current state of knowledge about integrative cerebral dynamics and transport phenomena indicates that poroelastic theory may provide a suitable framework to better understand various diseases. In this work, Multiple-Network Poroelastic Theory (MPET) is used to develop a novel spatio-temporal model of fluid regulation and tissue displacement within the various scales of the cerebral environment. The model is applied through two formats, a one-dimensional finite difference - Computational Fluid Dynamics (CFD) coupling framework, as well as a two-dimensional Finite Element Method (FEM) formulation. These are used to investigate the role of endoscopic fourth ventriculostomy in alleviating oedema formation due to fourth ventricle outlet obstruction (1D coupled model) in addition to observing the capability of the FEM template in capturing important characteristics allied to oedema formation, like for instance in the periventricular region (2D model).

Delayed relapse in pseudotumor cerebri due to new stenosis after transverse sinus stenting

A patient presented with recurrent severe pseudotumor cerebri (PTC). Transverse sinus stenting is a very effective treatment option, however stenosis and intracranial hypertension can recur. In our patient, stenting initially resulted in resolution of papilloedema. However, after 5 years, a new stenosis developed which required further stenting. This case highlights the fact that, in patients with PTC who undergo transverse sinus stenting, a small proportion require repeat treatment due to formation of a new stenosis, usually adjacent to the existing stent. Patients with severe disease, such as ours, may be at higher risk of recurrence. Regardless of the severity, all patients who undergo stenting should have regular ocular follow-up.

Spontaneous thrombosis of a basilar tip aneurysm after ventriculoperitoneal shunting

We present a case of a large unruptured basilar tip aneurysm with concomitant hydrocephalus. Complete thrombosis of the aneurysm was observed after ventriculoperitoneal shunting. Analyzing preoperative and postoperative MRI and DSA images, we identified reduced intracranial pressure and widening of the aneurysm-artery inclination angle as possible factors influencing spontaneous thrombosis. To the best of our knowledge, this is the first report of aneurysm thrombosis occurring after CSF diversion.

Reversible transverse sinus collapse in a patient with idiopathic intracranial hypertension

The association of idiopathic intracranial hypertension (IIH) with stenosis or narrowing of the transverse sinuses (TSs) is well known. However, there is debate as to whether the stenosis is a cause or consequence. Here we describe a case of IIH and narrowing of the TSs, with four relapses and recoveries after repeated CSF diversions with lumbar puncture (LP) over 2 months. Subsequently, implantation of a lumboperitoneal shunt (LPrS) ensured recovery. MR venography 20 months after LPrS showed normally calibrated TSs. We show repeated MR venography findings before and after the LPs, and discuss the pathogenesis of IIH in terms of the cause and effect relationship between IIH and sinus collapse.

Intracranial Pressure and Its Relationship to Glaucoma: Current Understanding and Future Directions

Retrospective and prospective studies looking at the role of cerebrospinal fluid pressure (CSFP)/intracranial pressure (ICP) have stimulated new theories and hypotheses regarding the underlying causal events for glaucoma. Most recently, studies supporting a low CSFP/ICP as a risk factor for glaucoma have been published. This review summarizes the current understanding of CSFP/ICP and its potential role in the pathogenicity of the disease.

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.

Incidental intrathecal injection of meglumine diatrizoate

Introduction:

Myelograghy is a process of instilling contrast medium to the subarachnoid space for evaluating the spinal column by radiography. There are various contrast solutions for different radiographic studies but not all of them are suitable for spinal column evaluation.

Case Presentation:

Our patient was a 60-year-old man who developed severe pain, tonic clonic convulsions and cardiopulmonary arrest after intrathecal injection of 14 mL of meglumine diatrizoate during an elective myelography procedure. Many of these cases would die or suffer from permanent sequelae if appropriate treatment is not received.

Conclusions:

Our subject recovered completely without any sequelae after receiving appropriate treatment in a multidisciplinary intensive care unit.

Management of raised intracranial pressure and hyperosmolar therapy

The management of raised intracranial pressure is undergoing rapid change. The choice of medical treatments to reduce intracranial pressure varies between institutions and regions of the world. The mainstay of therapy, however, continues to be the infusion of a hyperosmolar solution to achieve an osmotic gradient to force the exit of water from the brain. This review introduces the basic concepts of raised intracranial pressure, summarises several recent studies that have challenged dogma in the field, and provides practical advice on hyperosmolar treatment, based on personal experience and a critical reading of the literature.

Successful treatment of extensive cerebral venous sinus thrombosis using a combined approach with Penumbra aspiration system and Solitaire FR retrieval device

We present a young woman with rapidly progressive neurologic decline in the setting of malignant cerebral edema due to extensive superior sagittal sinus thrombosis and cortical venous thrombosis despite intravenous heparin administration. Complete revascularization of the occluded sinus was achieved using suction thrombectomy with the 5 max Penumbra catheter in combination with the Solitaire FR clot retrieval device. The successful endovascular treatment halted the progression of her cerebral edema, and the patient eventually had an excellent recovery after prolonged intensive medical therapy. To our knowledge, this is the first reported case describing such a combined mechanical approach for cerebral venous sinus thrombosis. The clot retrieval properties of the Solitaire device combined with direct aspiration via the newest generation Penumbra catheters may allow more rapid, safe and efficient revascularization than all previously reported endovascular treatments for this potentially devastating condition.

Successful treatment of extensive cerebral venous sinus thrombosis using a combined approach with Penumbra aspiration system and Solitaire FR retrieval device

We present a young woman with rapidly progressive neurologic decline in the setting of malignant cerebral edema due to extensive superior sagittal sinus thrombosis and cortical venous thrombosis despite intravenous heparin administration. Complete revascularization of the occluded sinus was achieved using suction thrombectomy with the 5 max Penumbra catheter in combination with the Solitaire FR clot retrieval device. The successful endovascular treatment halted the progression of her cerebral edema, and the patient eventually had an excellent recovery after prolonged intensive medical therapy. To our knowledge, this is the first reported case describing such a combined mechanical approach for cerebral venous sinus thrombosis. The clot retrieval properties of the Solitaire device combined with direct aspiration via the newest generation Penumbra catheters may allow more rapid, safe and efficient revascularization than all previously reported endovascular treatments for this potentially devastating condition.

Integrated flat detector CT and live fluoroscopic-guided external ventricular drain placement within the neuroangiography suite

Purpose

To demonstrate the feasibility of the application of integrated flat detector (FD) CT and fluoroscopic guidance (iGuide) for the placement of external ventricular drains (EVD) within the neuroangiography suite.

Methods

A retrospective review of a prospectively maintained endovascular database identified six patients who underwent EVD placement using iGuide. Patient characteristics, operator, number of passes, accuracy of placement, immediate and delayed periprocedural complications and radiation exposure were assessed.

Results

Five patients with subarachnoid hemorrhage and one patient with a large cerebellar infarct (average age 45.5 years (range 39–53), four women) underwent EVD placement within the angiography suite using iGuide. Four procedures were performed by a neuroradiologist and two by a neurosurgeon. All catheters were placed with a single pass and all terminated within the frontal horn of the ipsilateral lateral ventricle. No parenchymal or intraventricular hemorrhages were encountered after catheter placement. No patients experienced any immediate or delayed periprocedural complications. Radiation exposure related to the FD CTs required for placement was 593.7 mGy (range 539–673).

Conclusions

EVD placement under combined CT and fluoroscopic control within the neuroangiography suite is feasible. The technique predictably allows optimized EVD catheter placement with a single pass. We propose that this technique could improve the accuracy, and potentially reduce the complications, of EVD insertion in cerebrovascular patients.