Causes Of Elevated Intracranial Pressure Research Articles

Safety and Efficacy of Metformin for Idiopathic Intracranial Hypertension. A U.S-Based Real-World Data Retrospective Multicenter Cohort Study.

Idiopathic intracranial hypertension (IIH) remains a challenging condition to manage, with limited therapeutic options. This study investigated the potential of metformin as a novel treatment for IIH, exploring its effects on disease outcomes and safety profile. We conducted a retrospective cohort study using the TriNetX database, analyzing data from 2009 to August 2024. Patients diagnosed with IIH were included, with exclusions for other causes of elevated intracranial pressure and pre-existing diabetes. Propensity score matching was employed to balance cohorts according to age, sex, race, ethnicity, Hemoglobin A1C, and baseline body mass index (BMI) at the time of metformin initiation. Outcomes were assessed at various follow-up points up to 24 months. Our study initially comprised 1,268 patients in the metformin group and 49,262 in the control group, with notable disparities in several parameters. Post-matching, both cohorts were refined to 1,267 patients each after matching with metformin group. Metformin-treated patients showed significantly lower risks of papilledema, headache, and refractory IIH status at all follow-up points (p<0.0001). The metformin group also had reduced rates of therapeutic spinal punctures and acetazolamide continuation. BMI reductions were more pronounced in the metformin group, with significant differences observed from 6 months onward (p<0.0001). Notably, metformin's beneficial effects persisted independently of BMI changes. The safety profile of metformin was favorable, with no significant differences in adverse events compared to the control group which did not receive metformin during the study timeframe. Our study provides evidence for metformin's potential as a disease-modifying therapeutic approach in IIH, demonstrating improvements across multiple outcomes. The benefits appear to extend beyond weight loss, suggesting complex mechanisms of action. These findings warrant further investigation through prospective clinical trials to establish metformin's role in IIH management and explore its underlying therapeutic mechanisms.

Incidence, risk factors, and clinical outcomes of acute brain swelling associated with traumatic acute subdural hematoma: a retrospective study utilizing novel diagnostic criteria.

Post-traumatic acute brain swelling (ABS) is a major cause of elevated intracranial pressure and thus mortality. The current definition of post-traumatic ABS has certain limitations, and there is limited information available regarding ABS associated with traumatic acute subdural hematoma (ASDH). To investigate the incidence, risk factors, and clinical outcomes of ABS associated with traumatic ASDH. Retrospective study. Data for 161 patients diagnosed with traumatic ASDH were retrospectively collected. Novel computed tomography-based criteria were proposed for diagnosing ABS in patients with ASDH and determining its incidence. Univariate and multivariate logistic regression analyses were performed to explore the risk factors of post-traumatic ABS. The Glasgow Outcome Scale (GOS) score, mortality, and functional prognosis of all patients at discharge and the proportion of intraoperative malignant brain bulge in surgical patients were taken as clinical outcome measures. A total of 45 (28%) patients experienced post-traumatic ABS, exhibiting significantly lower Glasgow Coma Scale scores on admission (p < 0.001). The incidence of hemispheric and whole-brain swelling was 8.1% and 19.9%, respectively. Risk factors independently associated with post-traumatic ABS were: (1) age [odds ratio (OR) = 0.917, p < 0.001]; (2) platelet to white blood cell ratio (PWR) (OR = 0.887, p = 0.012); and (3) traumatic subarachnoid hemorrhage (SAH) (OR = 4.346, p = 0.005). The ABS cohort had a lower GOS score [2 (1-3) versus 4 (3-5); p < 0.001], higher mortality (46.7% versus 6.9%; p < 0.001), and higher proportion of unfavorable functional prognosis (75.6% versus 34.5%; p < 0.001) upon discharge compared to the no ABS cohort, along with higher proportion of intraoperative malignant brain bulge (43.8% versus 0%; p < 0.001). The incidence of ABS associated with ASDH is significantly high overall. Patients with ASDH who have young age, low PWR, and traumatic SAH are at an increased risk of developing post-traumatic ABS, and therefore of poor clinical outcomes.

Optic Nerve Sheath Diameter as a Predictor of Raised Intracranial Pressure Findings on Orbital Ultrasound

BACKGROUND&#x0D; Several studies have found an association between raised intracranial pressure (ICP) and optic nerve sheath diameter (ONSD) in conditions with severe head injury and intracranial bleeding. Idiopathic intracranial hypertension is also a cause of elevated ICP. Because the meninges and subarachnoid space around the optic nerve are continuous, a rise in ICP can be detected with an increase in ONSD. The objectives of this study were to correlate Optic Nerve Sheath Diameter (ONSD) with features suggestive of raised intracranial pressure on CT / MRI of the Brain and describe the features suggestive of raised intracranial pressure on CT/MRI Brain in clinically suspected patients.&#x0D; METHODS&#x0D; This was a case control study carried out in the Department of Radio-diagnosis at MGMCRI for suspected raised intracranial pressure evaluation. All these patients were subjected to ultrasound examination of the eye and the optic sheath diameter was measured while the patients were in supine posture. ONSD was measured on Mind ray DC8, and/or GE S7 Expert using High frequency linear probe on the closed upper eyelid with adequate aqueous gel as a coupling agent. ONSD was also measured in Philips 1.5T MRI and Ge optima 128 slice CT. Patients were followed up on whether they were treated surgically or medically and if they developed clinical signs of raised ICP such as headache, vomiting, raised blood pressure, double vision, confusion or loss of consciousness.&#x0D; RESULTS&#x0D; The raised ICP was observed in 30.67 % of study patients and the optic nerve sheath distension was observed in 37.33% of patients. The diagnostic accuracy of determining the optic nerve sheath diameter was equal such as area under curve, sensitivity and specificity as 0.833, 66.67% and 100 % respectively in both methods.&#x0D; CONCLUSIONS&#x0D; ONSD has emerged as an interesting option for measuring intracranial hypertension in brain-injured states, owing to its simplicity, non-invasive nature, and accessibility.

Sonographic Measurement of the Optic Nerve Sheath Diameter to Improve Detection of Elevated Intracranial Pressure

Rapid recognition of elevated intracranial pressure (ICP) is essential to avoid brain stem herniation and death. Brain stem herniation is a very serious disorder in which an excess of intracranial pressure causes part of the brain to be squeezed through the foramen magnum at the base of the skull. Increased pressure on the brain stem can lead to blood pressure and breathing problems and brain death, respiratory or cardiac arrest, permanent brain damage, coma and death. The aim of this work was to evaluate the diagnostic accuracy of using Optic Nerve Sheath Diameter (ONSD) measurements to detect elevated ICP compared to computed tomography (CT) brain scanning. A prospective, observational cross-sectional study of 100 randomly selected ICU patients with suspected elevated ICP at Cairo university hospitals and cardiothoracic surgical ICU of the National Heart Institute (NHI), Cairo, Egypt. Optic nerve ultrasonography (US) was performed on all patients; CT brain scanning was chosen as the gold standard for detecting elevated ICP. Results: the cause of elevated ICP, 51.3% of patients were admitted with head trauma P-value = 0.000, clinical signs of elevated ICP, 31.3% of patients developed convulsions and 26.3% showed Cushing reflex (P=0.004 and 0.010 respectively). Besides the Glasgow Coma Scale (GCS), patients with elevated ICP had a mean GCS score of 7 and patients without elevated ICP had mean GCS of 13 (P˂0.001). Regarding ONSD, mean average ONSD was 6 in patients with elevated ICP and 3.1 in patients without elevated ICP (P˂0.01), receiver operating characteristic (ROC) curve analysis revealed that ONSD greater than 4.31 mm was significant in prediction of elevated ICP compared to CT brain scanning with 94.8% sensitivity and 90.11% specificity. Conclusion: patients’ ONSD is a simple bedside technique that can accurately diagnose of elevated ICP compared to CT brain scanning. The diagnostic accuracy of ONSD using a 4.31 mm cut-off value can diagnose of elevated ICP with 94.8% sensitivity and 90.11% specificity.

A clinical and radiological study in patients with idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH) is one of the chronic causes of elevated intracranial pressure with no evident cause in neuroimaging and normal CSF analysis. It primarily affects overweight women of childbearing age.Aim of workTo describe the clinical picture of IIH, neuroimaging and response to treatment after 3 months follow up in a sample of Egyptian patients.Patients and methodsThis was a prospective study carried out on 25 patients presented at Alexandria University Hospital with symptomatology of IIH. All the patients were subjected to complete history taking, neurological examination, fundus examination, lumbar puncture, and MRI brain and MR cerebral venography. The patients were followed-up for 3 months for assessment of treatment response.ResultsPatients’ ages ranged from 1 0to 50 years, with a mean BMI 32.32 ± 5.28 kg m2. Headache was the presenting manifestation in 100% of the patients. About 60% of the sample were either misdiagnosed or had a delayed diagnosis. There was a significant positive correlation between CSF opening pressure (r = 0.504, p = 0.010), severity of headache (r = 0.472, p = 0.017) and grade of papilledema. Optic hydropes and empty sellaturcica were the most common MRI abnormalities occurring in 95.8% and 70.8%, respectively. Only 30% of the cases had normal MRV. Stenosis at genu junction and focal stenosis at transverse sinus occurred in 24% and 20% of the cases, respectively. Combined medical and serial lumbar puncture were the most effective line of therapy in the recruited patients.ConclusionHeadache is the most common presentation of IIH, and its severity is positively correlated with papilledema grade. CSF pressure is also positively correlated with papilledema grade.

An Update on Imaging in Idiopathic Intracranial Hypertension.

Neuroimaging plays an essential role in the diagnostic workup of idiopathic intracranial hypertension with the aims to exclude secondary causes of elevated intracranial pressure and to identify imaging signs that are commonly observed in this disorder. As a valuable expansion of brain imaging, the imaging of the retina using optical coherence tomography has been of increasing value. In particular, this is the case with the latest devices that allow a more accurate distinction between a reduction in retinal nerve fiber layer thickness due to an improvement of papilledema or due to a worsening caused by optic nerve atrophy. Although optical coherence tomography does not yet replace the other elements of the diagnostic workup, it is likely to play an increasing role in diagnosis and follow-up of idiopathic intracranial hypertension. The review focuses on the main findings in neuroimaging, including structural and vascular alterations as well as on the relevance of optical coherence tomography.

Characterizing the Response to Cerebrospinal Fluid Drainage in Patients with an External Ventricular Drain: The Pressure Equalization Ratio.

An external ventricular drain (EVD) is the gold standard for measurement of intracranial pressure (ICP) and allows for drainage of cerebrospinal fluid (CSF). Different causes of elevated ICP, such as CSF outflow obstruction or cerebral swelling, respond differently to CSF drainage. This is a widely recognized but seldom quantified distinction. We sought to define an index to characterize the response to CSF drainage in neurocritical care patients. We studied consecutive patients admitted to the neurointensive care unit who had an EVD. The EVD was closed for 30min prior to assessment. We documented pre-drainage ICP, opened EVD to drainage allowing CSF to drain until it ceased, and recorded post-drainage ICP at EVD closure. We calculated the pressure equalization (PE) ratio as the difference between pre-drainage ICP and post-drainage ICP divided by the difference between pre-drainage ICP and EVD height. We studied 60 patients (36 traumatic brain injury [TBI], 24 non-TBI). As expected, TBI patients had more signs of cerebral swelling on CT and smaller ventricles. Although TBI patients had significantly higher pre-drainage ICP (26 ± 10mm Hg) than non-TBI patients (19 ± 5mm Hg, p < 0.001) they drained less CSF (7cc vs. 4cc, p < 0.01). PE ratio was substantially higher in non-TBI than in TBI patients (0.86 ± 0.36 vs. 0.43 ± 0.31, p < 0.0001), indicating that non-TBI patients were better able to equalize pressure with EVD height than TBI patients. PE ratio reflects the ability to equalize pressure with the preset height of the EVD and differs substantially between TBI and non-TBI patients. A high PE ratio likely indicates CSF outflow obstruction effectively treated by CSF diversion, while a lower PE ratio occurs when cerebral swelling predominates. Further studies could assess whether the PE ratio would be useful as a surrogate marker for cerebral edema or the state of intracranial compliance.

Decompressive craniectomy in aneurysmal subarachnoid haemorrhage for hematoma or oedema versus secondary infarction

Purpose: Decompressive craniectomy (DC) has been proposed as lifesaving treatment in aneurysmal subarachnoid haemorrhage (aSAH) patients with elevated intracranial pressure (ICP). However, data is sparse and controversy exists whether the underlying cause of elevated ICP influences neurological outcome. The purpose of this study is to clarify the role of the underlying cause of elevated ICP on outcome after DC.Materials and methods: We retrospectively studied the one-year neurological outcome in a single-centre cohort to identify predictors of favourable (Glasgow Outcome Scale (GOS) 4–5) and unfavourable (GOS 1–3) outcome. Additionally, available individual patient data in the literature was reviewed with a special emphasis on the underlying reason for DC.Results: From 2006–2015, 53 consecutive aSAH patients underwent DC. Nine (17%) achieved favourable, 44 (83%) unfavourable outcome (31 patients died). One fourth of the patients undergoing DC for hematoma or (hematoma-related) oedema survived favourably (increasing to 46% for patients aged <51 years), versus none of the patients undergoing DC for secondary infarction. Analysis of individual data of 105 literature patients showed a similar trend, although overall outcome was much better: half of the patients undergoing DC for hematoma/oedema regained independence, versus less than one-fourth of patients undergoing DC for secondary infarction.Conclusions: DC in aSAH patients is associated with high rates of unfavourable outcome and mortality, but hematoma or oedema as underlying reason for DC is associated with better outcome profiles compared to secondary infarction. Future observational cohort studies are needed to further explore the different outcome profiles among subpopulations of aSAH patients requiring DC.

Early stage alterations of catecholamine and adrenocorticotropic hormone levels in posttraumatic acute diffuse brain swelling.

Posttraumatic acute diffuse brain swelling (PADBS) is characterized by serious brain bulk enlargement rapidly following trauma and is a major cause of elevated intracranial pressure and thus mortality. The pathogenesis of PADBS is not clearly understood, and the early stage alterations of catecholamine (CA) and adrenocorticotropic hormone (ACTH) levels in PADBS also remain largely unknown. The objective of this study was to investigate CA and ACTH levels in the patients with PADBS in the early stage and discuss the possible roles CA and ACTH in the pathogenesis of PADBS. It is a cross-sectional study. A group of patients with PADBS (n=10) was compared with a group of patients with severe brain injury (SBI) (n=33). A control group of healthy adults (n=25) was also included. Blood samples were obtained to measure levels of epinephrine (EPI), norepinephrine (NE), dopamine (DA), and ACTH as soon as the patients arrived at the neurosurgery department, which was done within 4h after trauma. Both SBI and PADBS groups of patients had higher levels of EPI, NE, DA, and ACTH than the control group. The PADBS group had significantly higher levels of EPI, NE, and ACTH than the SBI group. CA and ACTH levels are significantly increased in early stage PADBS. These results imply that CA and ACTH may play important roles in the pathogenesis of PADBS. To eliminate the effects of CA and ACTH at the early stage, and thereby protect the hypothalamus and brain stem, might be critical measures for treating patients with PADBS.

Optic nerve sheath diameter and lumbar puncture opening pressure in nontrauma patients suspected of elevated intracranial pressure

ObjectiveThe purpose of this study was to determine if patients with nontraumatic causes of elevated intracranial pressure (ICP) could be identified by ultrasound measurement of optic nerve sheath diameter (ONSD). It was hypothesized that an ONSD greater than or equal to 5 mm would identify patients with elevated ICP. MethodThis was a prospective observational trial comparing ONSD with ICP measured by opening pressure manometry on lumbar puncture (LP). The cohort consisted of a convenience sample of adult patients presenting to the emergency department, requiring LP. The ONSD measurement was performed before computed tomography and LP. The physician performing the LP was blinded to the result of the ONSD measurement. An opening pressure on manometry of greater than or equal to 20 cm H2O and an ONSD greater than or equal to 5 mm were considered elevated. ResultsFifty-one patients were included in our study, 24 (47%) with ICP greater than or equal to 20 cm H2O and 27 (53%) with ICP less than 20 cm H2O. The sensitivity of ONSD greater than or equal to 5 for identifying elevated ICP was 75% (95% confidence interval, 53%-90%) with specificity of 44% (25%-65%). The area under the receiver operator characteristic curve was 0.69 (0.54-0.84), suggesting a relationship between ONSD and ICP. ConclusionAn ONSD greater than or equal to 5 mm was associated with elevated ICP in nontraumatic causes of elevated ICP. Although a relationship exists, a sensitivity of 75% does not make ONSD measurement an adequate screening examination for elevated ICP in this patient population.

Update on intracranial hypertension and hypotension

The aim of this article is to review recent findings on the pathophysiology of idiopathic changes in intracranial pressure. The review will focus on idiopathic intracranial hypertension (IIH) and spontaneous intracranial hypotension (SIH). Substantial evidence indicates that IIH is associated with delayed absorption of cerebrospinal fluid (CSF). Stenoses of the transverse sinus are common in IIH, but their clinical significance has not been entirely clarified. Despite the observed efficacy of endovascular treatment in some IIH patients, a correlation between the extent of observed stenoses and the clinical course of the disease could not be demonstrated. The underlying cause of SIH is a spontaneous CSF leakage into the epidural space. Conservative treatment and the epidural blood patch remain the treatment of choice for this rare syndrome. Recent clinical evidence indicates that IIH is probably a result of CSF outflow abnormality rather than of CSF production. Further research is needed to elucidate the causes of elevated intracranial pressure and the mechanism leading to visual loss. Prospective randomized clinical trials are needed to clarify a possible therapeutic potential of endovascular treatment. Research efforts on SIH should focus further on associated connective tissue disorders predisposing to CSF leaks.

Headaches secondary to intraventricular silicone oil successfully managed with ventriculoperitoneal shunt.

To describe a case of intravitreal silicone oil (SO) migration into the cerebral ventricles with secondary chronic headaches. Retrospective case report. Chart review. Single patient. A 51-year-old man with a history of proliferative diabetic retinopathy underwent surgery for traction retinal detachment using SO. Postoperatively, he developed elevated intraocular pressure, headaches, and a blind painful eye, which was enucleated. Neuroimaging revealed SO within the cerebral ventricles. Five years after the initial retinal detachment surgery, the patient developed chronic headaches. Lumbar puncture revealed an elevated opening pressure. The headaches were initially managed medically. A ventriculoperitoneal shunt was placed after the headaches persisted, which resulted in their complete resolution at 6 weeks after shunt placement. Ocular hypertension after intravitreal SO placement may play a role in SO intracranial migration. In the case presented, intraventricular SO was the apparent cause of elevated intracranial pressure and headaches. As all published cases of intraventricular SO migration reporting intraocular pressure to this point have described ocular hypertension, careful monitoring of intraocular pressure and aggressive control of ocular hypertension in the presence of intravitreal SO is recommended.

Refractory Cerebrospinal Fluid Rhinorrhea Secondary to Occult Superior Vena Cava Syndrome and Benign Intracranial Hypertension: Diagnosis and Management

This study is designed to describe the association between benign intracranial hypertension (BIH) and spontaneous cerebrospinal fluid (CSF) rhinorrhea and address the effect of extracranial venous flow dynamics on intracranial pressure (ICP). We present a 58-year-old woman with refractory spontaneous CSF rhinorrhea who was later found to have superior vena cava syndrome. The patient had undergone two prior transnasal endoscopic repair attempts. In retrospect, a preoperative magnetic resonance venogram (MRV) suggested very prolonged cerebral transit time, despite otherwise normal intracranial venous anatomy. The CSF leak was repaired through a bifrontal craniotomy. The intraoperative and postoperative course was complicated due to the patient's significant comorbidities. She ultimately made a good recovery and has not had any further CSF rhinorrhea in more than 2 years of follow-up. Refractory, spontaneous CSF leak must prompt aggressive investigation for multiple causes of elevated ICP. A cerebral transit time can be obtained from scout imaging when a magnetic resonance angiogram or MRV is performed, and this may disclose elevated ICP if it is prolonged. If endoscopic transnasal repair fails, craniotomy and direct suture repair and autologous tissue reinforcement of the skull base may prove successful and durable, even if BIH persists.

Hypertension intracrânienne de l'enfant: de la physiopathologie à la prise en charge thérapeutique

The pathophysiology of elevated intracranial pressure (ICP) is assessed from a three cerebral compartment model and from brain compliance. The mechanisms leading to elevated ICP (expanding process, cerebral edema, brain swelling, hydrocephalus) and their consequences (brain herniation, ischemia-anoxia phenomenon, Cushing reaction and neurogenic pulmonary edema) are overviewed. The causes of elevated ICP in children are reported with emphasis on traumatology. Diagnostic procedures include clinical assessment, fundoscopy, cerebral computerized tomography scan and specific problems of cerebrospinal fluid investigation. Methods and results of intracranial pressure monitoring are reported. The treatment of elevated ICP is based upon clinical follow-up and monitoring of ICP. General therapeutic rules consist of adequate position, suppression of any neck, skull and abdominal compression, stimuli limitation and fluid restriction. Specific treatments include mechanical ventilation, sedation and analgesia, barbiturates, anticonvulsant drugs, mannitol, corticosteroids, hypothermia, enteral nutrition, and antibiotics.