Lumbar Puncture Opening Pressure Research Articles

Clinical and Radiological Characteristics of Non-Obese Female Patients with Idiopathic Intracranial Hypertension.

While the typical patient with idiopathic intracranial hypertension (IIH) is an obese female of childbearing age, there are unique patient populations, such as non-obese females, that have not been well studied. Characterizing this subpopulation may increase awareness our of it, which may prevent underdiagnosis and improve our understanding of IIH's underlying pathophysiology. We retrospectively reviewed electronic medical records and compared the clinical and radiological characteristics of non-obese (BMI < 30) and obese (BMI > 30) female patients with IIH. Two hundred and forty-six patients (age 32.3 ± 10) met our inclusion criteria. The non-obese patients (n = 59, 24%) were significantly younger than the obese patients (29.4 ± 9.9 vs. 33.2 ± 10.2, p = 0.004) and had higher rates of severe papilledema (Friesen 4-5; 25.4% vs. 11.8%, p = 0.019), scleral flattening (62.7% vs. 36.9%, p = 0.008), and optic nerve dural ectasia (78.0% vs. 55.6%, p = 0.044). Non-obese patients also had a tendency to have a higher lumbar puncture opening pressure (368 ± 92.7 vs. 344 ± 76.4, p = 0.062). Non-obese patients were three times more likely to present with a combination of scleral flattening and optic nerve dural ectasia (OR = 3.00, CI: 1.57-5.72, χ2 = 11.63, α < 0.001). Overall, non-obese females with IIH were found to have a more fulminant presentation, typified by higher rates of severe papilledema and radiological findings typical for IIH.

The Relationship between Lumbar Puncture Opening Pressure and Retinal Nerve Fiber Layer Thickness in the Diagnosis of Idiopathic Intracranial Hypertension: Is a Lumbar Puncture Always Necessary?

Idiopathic intracranial hypertension (IIH), is characterized by elevated intracranial pressure (ICP) without an identified cause. Today, lumbar puncture (LP) is the most common method used for diagnosis by measuring cerebrospinal fluid (CSF) pressure to reflect intracranial pressure. This invasive examination has significant disadvantages, such as complications and negative experiences for patients. Therefore, noninvasive methods for ICP measurement are desired. Optical coherence tomography (OCT) is widely used for the diagnosis and follow-up of IIH patients as it reflects papilledema. The aim of this study is to investigate the relationship between CSF pressure and OCT parameters and the ability of OCT in the diagnostic approach. In our study, patients who were followed up with a diagnosis of IIH with complete neuro-ophthalmological examinations, including visual acuity (VA), visual field, and OCT imaging within 24 hours before lumbar puncture, were retrospectively evaluated. CSF pressure, visual acuity LogMAR, mean deviation of visual fields, retinal nerve fiber layer (RNFL) thickness measured by OCT, and treatment protocols were obtained from our hospital data system. A total of 42 eyes of 21 patients were enrolled in the study. A statistically significant positive and moderate correlation was found between CSF pressure values and average RNFL thickness (r=0.507; P=0.001). The same relationship was demonstrated in all 4 quadrants: inferior, superior, nasal, and temporal. Increased peripapillary RNFL thickness in optic nerve head OCT may be correlated with increased ICP in IIH patients. A larger number of patients are needed to better understand the correlation between OCT parameters and CSF pressure in patients with IIH.

The impact of eating disorders on idiopathic intracranial hypertension.

Idiopathic intracranial hypertension (IIH) occurs more frequently in obese females of childbearing age. A link between eating disorders and poor outcome has been suggested but remains unproven. This prospective field study at two tertiary headache centers included patients with clinically suspected IIH after standardized diagnostic work-up. Eating disorders were evaluated using validated questionnaires (EDQs). Primary outcome was the impact of eating disorders on IIH severity and outcome, secondary outcome was the prevalence and type of eating disorders in IIH compared to controls. We screened 326 patients; 143 patients replied to the EDQs and were classified as 'IIH' or 'non-IIH' patients. The demographic profile of EDQ-respondents and non-respondents was similar. Presence of an eating disorder did not impact IIH severity (lumbar puncture opening pressure (p = 0.63), perimetric mean deviation (p = 0.18), papilledema (Frisén grad 1-3; p = 0.53)) nor IIH outcome (optic nerve atrophy (p = 0.6), impaired visual fields (p = 0.18)). Moreover, we found no differences in the prevalence and type of eating disorders when comparing IIH with non-IIH patients (p = 0.09). Eating disorders did not affect IIH severity or outcome. We found the same prevalence and distribution pattern of eating disorders in IIH and non-IIH patients advocating against a direct link between IIH and eating disorders.

Diffusion-Weighted Imaging Reveals Impaired Glymphatic Clearance in Idiopathic Intracranial Hypertension.

The pathophysiology underlying idiopathic intracranial hypertension (IIH) remains incompletely understood. While one theory postulates impaired cerebral glymphatic clearance in IIH, there is a paucity of methods to quantify glymphatic activity in human brains. The purpose of this study was to use advanced diffusion-weighed imaging to evaluate the glymphatic clearance of IIH patients and how it may relate to clinical severity. DWI was used to separately evaluate the diffusivity along the cerebral perivascular spaces and lateral association and projection fibers, with the degree of diffusivity used as a surrogate for glymphatic function (diffusion tensor image analysis along the perivascular space. Patients with IIH were compared with normal controls. Glymphatic clearance was correlated with several clinical metrics, including lumbar puncture opening pressure and Frisen papilledema grade (low grade: 0-2; high grade: 3-5). In total, 99 patients with IIH were identified and compared with 6 healthy controls. Overall, patients with IIH had significantly lower glymphatic clearance based on DWI-derived diffusivity compared with controls (P = .005). Additionally, in patients with IIH, there was a significant association between declining glymphatic clearance and increasing Frisen papilledema grade (P = .046) but no correlation between opening pressure and glymphatic clearance (P = .27). Furthermore, healthy controls had significantly higher glymphatic clearance compared with patients with IIH and low-grade papilledema (P = .015) and high-grade papilledema (P = .002). Lastly, patients with IIH and high-grade papilledema had lower glymphatic clearance compared with patients with IIH and low-grade papilledema (P = .005). Patients with IIH possess impaired glymphatic clearance, which is directly related to the extent of clinical severity. The DWI-derived parameters can be used for clinical diagnosis or to assess response to treatment.

Emergent cerebral venous stenting: A valid treatment option for fulminant idiopathic intracranial hypertension

BackgroundFulminant idiopathic intracranial hypertension (FIIH) is characterized by rapid, severe, progressive vision loss and often treated surgically. Cerebral transverse venous stenting (CTVS) is efficacious in IIH patients, but emergent CTVS in FIIH is rarely reported. We present our experience with emergent CTVS in patients with FIIH. MethodsSince 01/2019, an institutional protocol allowed emergent CTVS in FIIH patients with bilateral transverse sinus stenosis and gradient pressure > 15 on digital subtraction angiography (DSA). We retrospectively analyzed a prospective registry of all IIH patients with details of neurological and neuro-ophthalmological assessments before and after treatment, and subjective assessments of headache and tinnitus were made pre-and post-procedure. Results259 IIH patients, including 49 who underwent CTVS, were registered. Among them, five female patients met inclusion criteria for FIIH and underwent emergent CTVS. FIIH patients were younger (18.8 ± 1.64 vs 27.7 ± 4.85, p < 0.01), mean BMI was lower (30.8 ± 10.57 vs 34.6 ± 4.3, p < 0.01), and lumbar puncture opening pressure higher (454 ± vs 361 ± 99.4, p < 0.01) than that of IIH patients. They presented with acute visual loss, severe headache, papilledema, significant bilateral transverse sinus stenosis on CT-venography, and mean dominant side gradient pressure of 26.4 ± 6.2 on DSA. CTVS was performed without significant complications, resulting in remarkable improvement in headache, optical coherence tomography, and visual fields within 1 week. At 1-year follow-up (four patients) and 6-month follow-up (1 patient), there was complete resolution of papilledema and headache, and marked improvement in visual acuity. ConclusionsIn these patients, emergent-CTVS was a safe and effective treatment option for FIIH. Further evaluation is warranted.

The clinical findings to notice mild elevation of intracranial pressure in an otology clinic

Mildly elevated intracranial pressure appears to be a distinct pathology separate from idiopathic increased intracranial pressure and migraine. Many patients present with head fullness-pressure and dizziness, which is often suggestive of a clinical diagnosis of vestibular migraine. These patients may additionally have episodic vertigo as seen in endolymphatic hydrops and positional vertigo in addition to feeling dizzy. In most cases, hearing is normal. A long duration of the condition or a presence of associated ear pathologies, i.e., dehiscence, fistula, hypermobile footplate, or history of chronic ear infections can add hearing loss to clinical presentations. Low-pitch pulsatile tinnitus, when present, is an important symptom. The neuroimaging findings such as partially empty sella, blockage of the dural venous sinus or sigmoid sinus wall defects are frequently observed. The condition is diagnosed by measuring the lumbar puncture opening pressure. Typically, patients have normal cerebrospinal fluid chemistry and microscopy. Lowering the pressure during the lumbar puncture will resolve the patient's symptoms temporarily. Medical therapy is typically successful using carbonic anhydrase inhibitors and corrections of medical disorders that may be contributing to the increased pressure. A few require shunting or stenting procedures. In this review article, we define the condition in detail with illustrative cases that we collected from our practices.

Long-term monitoring of children with Pseudo Tumor Cerebri Syndrome by transbulbar sonography.

Determination of optic nerve sheath diameter (ONSD) with transbulbar sonography has become an easily accessible and time-effective tool in the assessment of increased intracranial pressure. The aim of our study was to evaluate the usefulness of transbulbar sonography in the initial diagnosis and in follow-up examinations of children and adolescents with the diagnosis of pseudotumor cerebri syndrome (PTCS). We retrospectively reviewed imaging results of 24 patients aged 0.75-17 years with PTCS. Serial transbulbar sonography examinations were performed between 2011 and 2021. Sonographic evaluation included the ONSD, papilledema and subarachnoid space. 240 sonographic measurements taken at 108 time points in 17 patients met the inclusion criteria. All patients underwent serial lumbar punctures and routine fundoscopy in close relation to transbulbar sonography. We found that ONSD values remained high in all patients. The longest follow-up period was dated 2498 days (6.84 years) after initial diagnosis. Papilledema resolved in close correlation to fundoscopy normalization. In 16/17 patients the subarachnoid space remained cystic in appearance. These findings were independent of clinical symptoms and lumbar puncture opening pressure. We conclude that transbulbar sonography is a useful diagnostic tool in the initial diagnostic workup of children with PTCS. On follow-up however ONSD values and the cystic transformation of the subarachnoid space remained pathologic in the majority of cases while papilledema resolved parallel to fundoscopy findings. Serial measurements of ONSD are therefore of limited value in the follow-up of patients with PTCS and cannot be considered a reliable tool in subsequent therapeutic decisions.

Seizures as the initial manifestation of Idiopathic Intracranial Hypertension (P2-9.001)

<h3>Objective:</h3> To describe the clinical and radiologic characteristics of 5 patients with seizure as a symptom of idiopathic intracranial hypertension (IIH). <h3>Background:</h3> Patients with IIH may have atypical presentations and may not meet the classic IIH diagnostic criteria. Recent reports suggest an association between IIH and seizures in patients with temporal encephaloceles, which are frequently observed in temporal lobe epilepsy and might be an epileptogenic focus. The aim of this study is to report patients with presumed IIH and seizures associated with encephaloceles. <h3>Design/Methods:</h3> NA <h3>Results:</h3> We report 5 patients (34–79 years old; 4 women, 1 man; body mass index mean 44.6 (25.6–60.6)) with generalized or focal epilepsy associated with encephaloceles in the basal frontal lobe or inferomedial temporal lobe. Three patients with temporal lobe encephaloceles had interictal epileptiform activity or focal temporal slowing in one or both temporal lobes. Other radiological findings included signs of chronic intracranial hypertension. Three patients had rhinorrhea from spontaneous cerebrospinal fluid (CSF) leak; all denied visual symptoms. One patient had mild papilledema, and 4 patients had chronic peripapillary changes suggesting previous papilledema. Three patients had a lumbar puncture opening pressure between 26 and 28 cm H₂O. <h3>Conclusions:</h3> These cases suggest that seizures related to basal encephaloceles likely result from untreated chronic intracranial hypertension, as can be seen in untreated or chronic IIH. Skull base meningoencephaloceles and spontaneous CSF leak are two manifestations of the same bony defects that are likely part of the expanding IIH spectrum. The diagnosis of IIH remains presumptive, especially without papilledema. Radiological findings of chronic intracranial hypertension in patients with isolated seizures should prompt funduscopic examination looking for papilledema and skull base imaging screening for basal encephaloceles that may help guide epilepsy treatment. <b>Disclosure:</b> Dr. Bouthour has nothing to disclose. Dr. Al-Balushi has nothing to disclose. Dr. Dattilo has nothing to disclose. Dr. Newman has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for GenSight. Dr. Newman has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Chiesi. Dr. Newman has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Neurophoenix. Dr. Newman has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Stoke. Dr. Newman has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Avidity. Dr. Newman has received personal compensation in the range of $0-$499 for serving on a Scientific Advisory or Data Safety Monitoring board for Neurodiem. The institution of Dr. Newman has received research support from GenSight. The institution of Dr. Newman has received research support from Chiesi/Santhera. The institution of Dr. Newman has received research support from NINDS/NIH. Dr. Newman has received publishing royalties from a publication relating to health care. Dr. Newman has received publishing royalties from a publication relating to health care. Dr. Newman has received publishing royalties from a publication relating to health care. Dr. Biousse has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Gensights Biologic. Dr. Biousse has received personal compensation in the range of $0-$499 for serving as a Consultant for Neurophoenix. The institution of Dr. Biousse has received research support from NIH. Dr. Biousse has received publishing royalties from a publication relating to health care. Dr. Biousse has received publishing royalties from a publication relating to health care.

Elevated neurofilament light chain CSF/serum ratio indicates impaired CSF outflow in idiopathic intracranial hypertension

BackgroundImpaired cerebrospinal fluid (CSF) homeostasis is central to the pathogenesis of idiopathic intracranial hypertension (IIH), although the precise mechanisms involved are still not completely understood. The aim of the current study was to assess the CSF/serum ratio of neurofilament light chain levels (QNfL) as a potential indicator of functional CSF outflow obstruction in IIH patients.MethodsNfL levels were measured by single molecule array in CSF and serum samples of 87 IIH patients and in three control groups, consisting of 52 multiple sclerosis (MS) patients with an acute relapse, 21 patients with an axonal polyneuropathy (PNP), and 41 neurologically healthy controls (HC). QNfL was calculated as the ratio of CSF and serum NfL levels. Similarly, we also assessed the CSF/serum ratio of glial fibrillary acidic protein (QGFAP) levels to validate the QNfL data. Routine CSF parameters including the CSF/serum albumin ratio (QAlb) were determined in all groups. Lumbar puncture opening pressure of IIH patients was measured by manometry.ResultsCSF-NfL levels (r = 0.29, p = 0.008) and QNfL (0.40, p = 0.0009), but not serum NfL (S-NfL) levels, were associated with lumbar puncture opening pressure in IIH patients. CSF-NfL levels were increased in IIH patients, MS patients, and PNP patients, whereas sNfL levels were normal in IIH, but elevated in MS and PNP. Remarkably, QNfL (p < 0.0001) as well as QGFAP (p < 0.01) were only increased in IIH patients. QNfL was positively correlated with CSF-NfL levels (r = 0.51, p = 0.0012) and negatively correlated with S-NfL levels (r = − 0.51, p = 0.0012) in HC, while it was only positively associated with CSF-NfL levels in IIH patients (r = 0.71, p < 0.0001). An increase in blood-CSF barrier permeability assessed by QAlb did not lead to a decrease in QNfL in any cohort.ConclusionsThe observed elevation of QNfL in IIH patients, which was associated with lumbar puncture opening pressure, indicates a reduced NfL transition from the CSF to serum compartment. This supports the hypothesis of a pressure-dependent CSF outflow obstruction to be critically involved in IIH pathogenesis.

Optic nerve head diffusion-weighted magnetic resonance imaging and apparent diffusion coefficient values as measuring tools for papilledema grade in idiopathic intracranial hypertension

Aim The aim of this study was to explore if there is a relationship between the grade of papilledema and MRI diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) values of the optic nerve head (ONH) in patients having idiopathic intracranial hypertension (IIH). Patients and methods This is a prospective study that was conducted between March 2020 and June 2022 on 285 patients diagnosed as having IIH, who were subjected to meticulous clinical examination, visual field testing, color vision testing, and orbital MRI done within one week of diagnosis. ONH signal intensity was graded and then compared with papilledema grade, and the results were analyzed. Results The study included 285 patients (156 females and 129 males), with a mean age of 30.8±9.6 years, definitely diagnosed as having IIH with lumbar puncture opening pressure ranging from 18 to 58 cmH2O (mean=35.6±9.8 cmH2O). The papilledema grades were grade I (121 patients), grade II (136 patients), grade III (21 patients), and grade IV (seven patients). ADC values of the ONH were found to be gradually decreased with higher papilledema grades among cases. In addition, according to papilledema grading, in grade I, 67% of the patients showed no DWI changes, whereas in grade II, 97% of the patients showed DWI changes in the ONH. In grades III and IV, all patients showed DWI changes. Conclusion MRI can be considered as a diagnostic tool for papilledema. In addition, low ADC values and diffusion restriction can be used as indicators for the severity of ONH insult in cases of increased intracranial tension.

Elevated lumbar puncture opening pressure in aseptic meningitis

ObjectivesElevated lumbar puncture opening pressure (ELPOP) is a reported but understudied phenomenon in aseptic meningitis. This study aimed to characterize the features of ELPOP in aseptic meningitis patients. MethodsAn observational, retrospective, single-center study was conducted. We included all adult patients diagnosed with aseptic meningitis or meningoencephalitis from October 2015 to May 2017, for whom lumbar puncture opening pressure (LP OP) was measured. OP > 25 cm H2O was documented as ELPOP. Patients’ demographic characteristics, clinical data, laboratory and cerebrospinal fluid (CSF) results, as well as optic disc appearance were analyzed. ResultsAmong 116 patients (61 males) included, 16 patients (14 %) had ELPOP (11 males). The average age of those patients was 32.4 years (SD = 9.8), and the mean OP was 31.7 cm H2O (SD = 6.02) as opposed to the mean normal LPOP (NLPOP) of16.13 cm H2O (SD = 4.15). Body mass index (BMI) was significantly higher in the ELPOP group (p = 0.0081). Funduscopic examination was documented in 15/16 patients in the ELPOP group and revealed swollen optic discs in 6 (40 %) patients. Fundus examination was performed in 62 patients in the NLPOP group, of whom 2 (3.2 %) had a swollen disc. There was no difference in CSF content between groups. ConclusionsThis study fills the void of information lacking on the frequency of ELPOP in aseptic meningitis. Its association with increased BMI may be related to the pathogenesis. LP OP should be measured in all patients with aseptic meningitis. Additional research is needed to determine the threshold of tolerated intracranial pressure (ICP).

Malignant Idiopathic Intracranial Hypertension

A 24-year-old woman with a body mass index of 28 presented with 2 weeks of progressive vision loss and 2 months of headache. Visual acuity was 20/400 in both eyes, and examination showed Frisén grade 5 papilledema with extensive retinal hemorrhage and exudates (Figs A[OD = right eye] and B [OS = left eye]). Imaging did not show evidence of mass lesions or dural venous sinus thrombosis, and lumbar puncture opening pressure was 46 cm H2O with normal cerebrospinal fluid contents, consistent with idiopathic intracranial hypertension.

Cerebrospinal Fluid Shunting in Children with Hydrocephalus and Increased Intracranial Pressure Secondary to Human Immunodeficiency Virus–Related Cryptococcal Meningitis

Hydrocephalus and increased intracranial pressure secondary to human immunodeficiency virus-related cryptococcal meningitis are rare in children. The role and outcomes of cerebrospinal fluid (CSF) shunting in children are not well reported. We report our experience with CSF shunting in the management of this condition in children over a 14-year period. This was a retrospective review of data collected from a single neurosurgery unit. Data collected included demographics, clinical characteristics, Glasgow Coma Scale score, lumbar puncture opening pressure, antiretroviral therapy, laboratory results, neuroimaging findings, shunting procedures, complications, and mortality. Seventeen children underwent CSF shunting. Median age was 10 years (range, 6-13), most being male (76%). All children were on antiretroviral therapy. Median Glasgow Coma Scale score was 15 (interquartile range [IQR], 14-15). Clinical characteristics included headaches (100%), visual impairment (82%), and seizures (47%). Lumbar puncture opening pressure was >30 cm H2O in 88% of children. Median CD4 count was 45 cells/μL (IQR, 17-56). Computed tomography brain scans showed hydrocephalus in 14 children (82%). Surgical procedures included ventriculoperitoneal shunts (82%) and lumboperitoneal shunts (18%). Shunt complications included infection (18%) and obstruction (18%). Staphylococcus aureus was cultured in all infections. Median follow-up was 45 months (IQR, 7.5-74). Three children (18%) died during the admission period. Ten children (59%) were alive at 1 year follow-up. This study is the largest series reporting on CSF shunting of hydrocephalus and increased intracranial pressure in children with human immunodeficiency virus-related cryptococcal meningitis. Treatment with ventriculoperitoneal shunt and lumboperitoneal shunt regardless of the CD4 count is an important option in suitable children to reduce mortality.

Current perspectives on the recognition and diagnosis of low CSF pressure headache syndromes

ABSTRACT Introduction Headaches occur when cerebrospinal fluid (CSF) pressure drops following dural puncture or trauma or spontaneously. As the features of these headaches and their accompanying symptoms might not be typical, low CSF pressure headache syndromes, and spontaneous intracranial hypotension in particular, are often misdiagnosed and underdiagnosed. Areas covered The aim of this narrative review is to summarize the most recent evidence regarding the clinical presentation and the diagnosis of low CSF pressure headache syndromes. Expert opinion The clinical spectrum low CSF pressure headache syndromes varies significantly and key signs might be missing. Low CSF pressure headache syndromes should be included in the differential diagnosis of any case of refractory headache, even when the headache is not orthostatic, or there are normal neuroimaging findings, and/or lumbar puncture opening pressure is within normal limits. Future research should focus on controlled interventional studies on the treatment of low CSF pressure headache syndromes, which are currently lacking.

Venous Sinus Stenting for Low Pressure Gradient Stenoses in Idiopathic Intracranial Hypertension.

Medically refractory idiopathic intracranial hypertension (IIH) is frequently treated with venous sinus stenosis stenting with high success rates. Patient selection has been driven almost exclusively by identification of supraphysiological venous pressure gradients across stenotic regions based on theoretical assessment of likelihood of response. To explore the possibility of benefit in low venous pressure gradient patients. Using a single-center, prospectively maintained registry of patients with IIH undergoing venous stenting, we defined treatment groups by gradient pressures of ≤4, 5 to 8, and >8 mmHg based on the most frequently previously published thresholds for stenting. Baseline demographics, clinical, and neuro-ophthalmological outcomes (including optical coherence tomography and Humphrey visual fields) were compared. Among 53 patients, the mean age was 32 years and 70% female with a mean body mass index was 36 kg/m 2 . Baseline characteristics were similar between groups. The mean change in lumbar puncture opening pressure at 6 months poststenting was similar between the 3 groups (≤4, 5-8, and >8 mmHg; 13.4, 12.9, and 12.4 cmH 2 O, P = .47). Papilledema improvement was observed across groups at 6 months (100, 93, and 86, P = .7) as were all clinical symptoms. The mean changes in optical coherence tomography retinal nerve fiber layer (-30, -54, and -104, P = .5) and mean deviation in Humphrey visual fields (60, 64, and 67, P = .5) at 6 weeks were not significantly different. Patients with IH with low venous pressure gradient venous sinus stenosis seem to benefit equally from venous stenting compared with their higher gradient counterparts. Re-evaluation of our restrictive criteria for this potentially vision sparing intervention is warranted. Future prospective confirmatory studies are needed.

Association of Amount of Weight Lost After Bariatric Surgery With Intracranial Pressure in Women With Idiopathic Intracranial Hypertension.

Background and ObjectivesThe idiopathic intracranial hypertension randomized controlled weight trial (IIH:WT) established that weight loss through bariatric surgery significantly reduced intracranial pressure when compared with a community weight management intervention. This substudy aimed to evaluate the amount of weight loss required to reduce intracranial pressure and to explore the effect of different bariatric surgical approaches.MethodsIIH:WT was a multicenter randomized controlled trial. Adult women with active idiopathic intracranial hypertension and a body mass index ≥35 kg/m2 were randomized to bariatric surgery or a community weight management intervention (1:1). This per-protocol analysis evaluated the relationship between intracranial pressure, weight loss, and the weight loss methods. A linear hierarchical regression model was used to fit the trial outcomes, adjusted for time, treatment arm, and weight.ResultsSixty-six women were included, of whom 23 had received bariatric surgery by 12 months; the mean age was 31 (SD 8.7) years in the bariatric surgery group and 33.2 (SD 7.4) years in the dietary group. Baseline weight and intracranial pressure were similar in both groups with a mean weight of 119.5 (SD 24.1) and 117.9 (SD 19.5) kg and mean lumbar puncture opening pressure of 34.4 (SD 6.3) and 34.9 (SD 5.3) cmCSF in the bariatric surgery and dietary groups, respectively. Weight loss was significantly associated with reduction in intracranial pressure (R2 = 0.4734, p ≤ 0.0001). Twenty-four percentage of weight loss (weight loss of 13.3 kg [SD 1.76]) was associated with disease remission (intracranial pressure [ICP] ≤ 25 cmCSF). Roux-en-Y gastric bypass achieved greater, more rapid, and sustained ICP reduction compared with other methods.DiscussionThe greater the weight loss, the greater the reduction in ICP was documented. Twenty four percentage of weight loss was associated with disease remission. Such magnitude of weight loss was unlikely to be achieved without bariatric surgery, and hence, consideration of referral to a bariatric surgery program early for those with active idiopathic intracranial hypertension may be appropriate.Trial RegistrationClinicalTrials.gov Identifier: NCT02124486; ISRCTN registry number ISRCTN40152829; doi.org/10.1186/ISRCTN40152829.Classification of EvidenceThis study provides Class II evidence that weight loss after bariatric surgery results in reduction in intracranial pressure in adult women with idiopathic intracranial hypertension. This study is Class II because of the use of a per-protocol analysis.

Bariatric surgery versus community weight management intervention for idiopathic intracranial hypertension: a randomised controlled trial

ObjectiveThe IIH weight trial (IIH: WT) aimed to compare the efficacy of bariatric surgery with a community weight management intervention (CWI) in active IIH.MethodsThis was a five-year randomized control trial which enrolled participants between March 1, 2014 and May 25, 2017 at five NHS hospitals in the United Kingdom. Participants with active IIH and body mass index (BMI) ≥35kg/m2 were screened. The primary outcome was change in intracranial pressure (ICP) measured by lumbar puncture (LP) opening pressure (OP) at 12 months.ResultsSixty-six women were randomised (mean age, 32 years). ICP was significantly lower in the bariatric surgery arm at 12 months (adjusted mean difference -6.00cm cerebrospinal fluid [CSF] 95% confidence interval [CI] -9.5 to -2.4]; p= 0.001) and at 24 months (adjusted mean difference -8.2cmCSF [95% CI, -12.2 to -4.2]; p&lt; 0.001) compared with the CWI arm. Weight was significantly lower in the bariatric surgery arm at 12 months (adjusted mean difference -21.4Kg 95% CI, -32.1 to -10.7]; p&lt; 0.001) and at 24 months (adjusted mean difference -26.6kg [95% CI, -37.5 to -15.7]; p&lt; 0.001) compared with the CWI arm. Quality of life (SF36, physical component score) improved significantly at 12 and 24 months (adjusted mean dif- ference p=.043; p=.006, respectively).Conclusions and RelevanceIn this study of women with active IIH and a BMI ≥35kg/m2, bariatric surgery was superior to a CWI in lowering ICP.soozmollan@doctors.org.uk

Invention of a non-invasive intracranial pressure (ICP) monitoring system – an enlightenment from a hydrocephalus study

Background Mechanical obstruction is the most common cause of shunt failure for hydrocephalic patients. However, the diagnosis is extremely challenging and often requires invasive testing methods. Thus, a simple and non-invasive technique is in urgent need to predict the intracranial pressure (ICP) of hydrocephalic patients during their post-surgical follow-up, which could help neurosurgeons to determine the conditions of the shunt system. Materials and methods Two groups of patients were enrolled in the current study. In group I, patients were enrolled as they were diagnosed with high ICP hydrocephalus and received shunt surgery. The shunt valve pressures were taken for their post-surgical ICP. Meanwhile, the participants of group II exhibited abnormally increased lumbar puncture opening pressure (LPOP; from 180 to 400 mmH2O). Both the ICP and LPOP were used to match with their corresponding tympanic membrane temperature (TMT). Results When patients’ ICP were in the normal range (group I, from 50 to 180 mmH2O), the TMT correlated with ICP in a linear regression model (R 2  = 0.59, p  < 0.001). Interestingly, when patients exhibited above-normal ICP (LPOP was from 180 to 400 mmH2O), their TMT fit well with the ICP in a third-order polynomial regression (R 2  = 0.88). When the ICP was 287.98 mmH2O, the TMT approached the vertex, which was 38.54 °C. Based on this TMT-ICP algorithm, we invented a non-invasive ICP monitor system. Interestingly, a tight linear correlation was detected between the ICP data drawn from the non-invasive device and Codman ICP monitoring system (R 2  = 0.93, p  < 0.01). Conclusions We believe the TMT-ICP algorithm (the Y-Jiang model) could be used for preliminary prediction of shunt malfunction as well as monitoring ICP changes.

Validation of optic nerve sheath diameter as a bedside noninvasive tool in comparison with lumbar puncture opening pressure in patients suspected of elevated intracranial pressure

Objective The aim was to assess the diagnostic accuracy of optic nerve sheath diameter (ONSD) compared with lumbar puncture opening pressure (LPOP) and computed tomography in diagnosing elevated intracranial pressure (ICP) for critically ill patients. Moreover, the study evaluated the diagnostic ability of ONSD as a screening test for cerebral edema.Background Recently, linear relationships have been detected between ICP and ONSD, proposing ultrasound measurements as a possible noninvasive method.Patients and methods The authors performed a prospective study that included 50 patients with disturbed consciousness of unknown etiology, who were admitted to the ICUs at Beni-Suef University hospital during the period from September 2017 to September 2019. ONSD was measured by ultrasonography.Results Measurement of the right ONSD was 0.62±0.084 cm, whereas measurement of the left ONSD was 0.61±0.083 cm. The mean of two eyes was 0.61±0.09 cm, and the LPOP was 19.96±4.69 cmH2O. Overall, 36 (72%) patients had ONSD greater than 0.6 cm. Besides, 31 (62%) patients had LPOP greater than 20 cmH2O. There was a significant positive correlation between average ONSD and LPOP. Receiver operating characteristic (ROC) curve showed that ONSD greater than 0.6 cm had a diagnostic value of elevated ICP with an area under the curve of 0.872 (95% confidence interval: 0.646–0.936) with a sensitivity of 95% and specificity of 77%, with P-value of 0.001. ROC curve analysis was used for prediction of increased ICP using average ONSD compared with CT where the ROC curve showed that ONSD greater than 0.6 cm had a diagnostic value with an area under the curve of 0.606 (95% confidence interval: 0.51–0.72) with a sensitivity of 83% and specificity of 56%, with P-value of 0.028.Conclusions ONSD is significant in prediction of elevated ICP, with a good positive correlation with LPOP as a gold standard reference.

Comparison of Optic Nerve Sheath Diameters Measured by Optic Ultrasonography Before and After Lumbar Puncture in Idiopathic Intracranial Hypertension Patients.

Idiopathic intracranial hypertension (IIH) symptoms include headache, blurred vision, and papilledema which may lead to permanent vision loss unless diagnosed and treated. Definitive diagnosis of IIH usually requires the measurement of intracranial pressure (ICP) via lumbar puncture (LP) which is an invasive and unwanted technique for patients. In our study, optic nerve sheath diameters (ONSD) were measured before and after lumbar puncture in IIH patients and the relationship of these measurements with ICP changes was evaluated as well as the effect of decreasing cerebrospinal fluid (CSF) pressure after a lumbar puncture on ONSD. Thus, we want to investigate whether optic nerve ultrasonography (USG) is a useful tool instead of the invasive LP for the diagnosis of IIH. A total of 25 patients who applied to the neurology clinics of Ankara Numune Training and Research Hospital between May 2014 and December 2015 and were diagnosed with IIH were included in the study. The control group consisted of 22 individuals who applied with complaints other than headaches, visual impairment or tinnitus. Optic nerve sheath diameters were measured from both eyes before and after the LP. After pre-LP measurements were taken, opening and closing CSF pressure was measured. In the control group, ONSD was measured with optic USG. Mean age of the IIH group and the control group was determined as 34.8±11.5 and 45.8±13.3 years, respectively. In the patient group, mean CSF opening pressure was 33.9±8.0 cm H2O and mean closing pressure was 18.1±4.7 cm H2O. Mean ONSD measured pre-LP was 7.1±1.0 mm in the right eye and 6.9±0.7 mm in the left eye, while mean post-LP ONSD was 6.7±0.9 mm in the right eye and 6.4±0.8 mm in the left eye. There was a statistically significant difference between ONSD values before and after the LP (p=0.006 for the right eye, p<0.001 for the left eye). In the control group, mean ONSD was 5.4±0.7 mm in the right eye and 5.5±0.6 mm in the left eye, and a statistically significant difference was found between ONSD values before and after the LP (p<0.001 for the right eye and left eye). A significant positive correlation was determined between left ONSD measurements before the LP and CSF opening pressure (r=0.501, p=0.011). In the present study, it was found that ONSD measurement by optic USG significantly displays increased ICP, and decreasing pressure via LP is rapidly reflecting ONSD measurement. Based on these findings, it is suggested that ONSD measurements by optic USG, a non-invasive method, can be used in the diagnosis and follow-up of IIH patients.