Measurement Of Opening Pressure Research Articles

Headache and Other Factors Modifying Cerebrospinal Fluid Opening Pressure in Pediatric Patients.

Cerebrospinal fluid opening pressure values are associated with various neurologic diseases; however, numerous factors can modify this measurement. This study aims to describe factors related to modifications in opening pressure measurements in pediatric patients. Methods: A retrospective analysis of lumbar punctures in pediatric patients conducted by the neuropediatrics group with institutional standardization. Bivariate and linear regression analyses were performed to determine the association between opening pressure and variables included in the study. Results: 544 events, median age 107 months, median opening pressure 19.7 cm H2O. Bivariate analysis found no association with medication use; anesthetics that increased opening pressure were remifentanil (P = .02) and propofol (P = .05), along with a positive linear correlation between opening pressure and age (P < .0001). Multiple linear regression analysis revealed that age, BMI, male gender, and remifentanil use were associated with an increase in opening pressure, whereas corticosteroid withdrawal was associated with a reduction in opening pressure. There is an interaction between age and headache, with an association with increased opening pressure up to around 140 months. Conclusion: This study identifies factors associated with changes in opening pressure, crucial for estimating normal opening pressure values in children. Headaches, anesthetic use, and corticosteroid withdrawal are confirmed as significant factors.

Persistent Elevation of Opening Pressure Despite Treatment and Symptom Resolution in Pediatric Intracranial Hypertension

BackgroundCurrently no guidelines for repeating a lumbar puncture to guide management in primary intracranial hypertension (PIH) exist. MethodsAn institutional database of patients 18 years and younger followed in the institution’s pediatric intracranial hypertension clinic was examined for opening pressure changes in PIH at diagnosis, before medication wean, and following medication wean, as well as to examine whether measurements at the time of diagnosis differed between those with and without disease recurrence. ResultsForty-two patients were included in this study; 36% were male and the mean age at diagnosis was 11.01 years. Treatment duration averaged 9.68 months in those without recurrence and 8.5 months in those with recurrence. Average body mass index percentile of patients with disease recurrence was 83.7 and 72.1 in those without recurrence (P = 0.16). Average opening pressure values of all patients at diagnosis, prewean, and postwean was 36.53 cm H2O, 30.7 cm H2O, and 31.1 cm H2O, respectively. There was no statistically significant difference in opening pressures across these time points (P = 0.14). The change in opening pressure from diagnosis to postwean was statistically significant with a reduction of 5.18 cm H2O (P = 0.04). There was no statistical difference between change in opening pressure at diagnosis versus postwean between those with and without recurrence (P = 0.17). ConclusionsThis clinical observational study suggests that mean opening pressure measurements in patients with PIH remain elevated both before and after medication wean despite papilledema resolution and patient-reported PIH symptoms. Clinically, this suggests that other features such as signs of optic disc edema and symptoms should be used to inform a clinical determination of disease recurrence and treatment course.

Increased Intracranial Pressure in Pediatric Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease.

Elevated intracranial pressure (ICP) in myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) has been largely unexplored. The objectives of this study were to determine the frequency of increased ICP in MOGAD and its association with disease course and outcomes and to highlight cases requiring medical and/or surgical management of increased ICP. In this retrospective, single-center cohort study, we examined the clinical and paraclinical data from the initial presentation and follow-up data of children diagnosed with MOGAD. In those with opening pressure (OP) measurements, univariate analyses were used to evaluate factors associated with increased ICP, which was defined as OP > 28 cm H2O. We also present a case series of patients with or without OP measurement who required medical and/or surgical management of increased ICP. Of 86 children with MOGAD, 43 (50.0%) had an OP recorded and 7 (8.1%) required ICP management. In those with OP recorded, the median (interquartile range) OP for the different MOGAD phenotypes were: 30.0 (22.8-41.6) (acute disseminated encephalomyelitis, ADEM), 20.5 (16.1-23.6) (optic neuritis), 17.0 (17.0-22.5) (myelitis), and 19.5 (16.5-29.3) (other) cm H20. Overall, 20.9% had increased ICP based on an OP > 28 cm H2O, of whom 77.8% presented with ADEM. In a subgroup analysis of those presenting with ADEM, those with an elevated ICP had longer hospital stay (p = 0.007) and neurologic disability (defined as modified Rankin Scale >1) (p = 0.049). In those with or without OP recorded, 7 (6 with ADEM, one with cerebral cortical encephalitis) required ICP-directed therapies. Findings on brain MRI in these 7 children revealed extensive disease burden with bilateral cerebral involvement and evidence of restricted diffusion. While neuropsychological data in this small subset revealed significant variability, all sustained identifiable deficits after discharge, including attention-deficit hyperactivity disorders and language and learning disorders. In pediatric MOGAD, increased OP and ADEM at initial presentation were associated with longer hospital stays and greater long-term morbidity. Although invasive ICP monitoring has not been specifically advocated in the management of MOGAD, it is important to recognize signs and symptoms of increased ICP in these patients and consider ICP monitoring and management strategies based on clinical and radiologic findings, especially in those presenting with ADEM and with OP > 28 cm H2O.

Idiopathic Intracranial Hypertension: A Case Report

Background: Optic nerve head edema is a serious finding for which multiple etiologies need to be considered. When optic nerve head edema is observed bilaterally, among the top differentials is idiopathic intracranial hypertension (IIH), also known as primary pseudotumor cerebri. An emergent magnetic resonance image with and without contrast as well as venography and lumbar puncture with opening pressure measurement must be performed to diagnose and determine management. Case Report: This case specifically features a 30-year-old Caucasian female with bilateral optic disc edema secondary to IIH. In addition to discussing the details regarding this patient’s case, this report highlights pertinent imaging, visual testing, and co-management. Conclusion: Important caveats to treatment and management of the condition, and other underlying complications of IIH are discussed. Close monitoring of papilledema, visual acuity, and visual field, along with co-management with neurology and neuro-ophthalmology will provide optimum care.

A novel method for assessment of airway opening pressure without the need for low-flow insufflation

BackgroundAirway opening pressure (AOP) detection and measurement are essential for assessing respiratory mechanics and adapting ventilation. We propose a novel approach for AOP assessment during volume assist control ventilation at a usual constant-flow rate of 60 L/min.ObjectivesTo validate the conductive pressure (Pcond) method, which compare the Pcond—defined on the airway pressure waveform as the difference between the airway pressure level at which an abrupt change in slope occurs at the beginning of insufflation and PEEP—to resistive pressure for AOP detection and measurement, and to compare its respiratory and hemodynamic tolerance to the standard low-flow insufflation method.MethodsThe proof-of-concept of the Pcond method was assessed on mechanical (lung simulator) and physiological (cadavers) bench models. Its diagnostic performance was evaluated in 213 patients, using the standard low-flow insufflation method as a reference. In 45 patients, the respiratory and hemodynamic tolerance of the Pcond method was compared with the standard low-flow method.Measurements and main resultsBench assessments validated the Pcond method proof-of-concept. Sensitivity and specificity of the Pcond method for AOP detection were 93% and 91%, respectively. AOP obtained by Pcond and standard low-flow methods strongly correlated (r = 0.84, p < 0.001). Changes in SpO2 were significantly lower during Pcond than during standard method (p < 0.001).ConclusionDetermination of Pcond during constant-flow assist control ventilation may permit to easily and safely detect and measure AOP.

Intraindividual variability of the Eustachian tube function: a longitudinal study in a pressure chamber.

The Eustachian tube (ET) is essential for fast and direct pressure equalisation between middle ear and ambient pressure. It is not yet known to what extent Eustachian tube function in healthy adults changes in a weekly periodicity due to internal and external factors. This question is particularly interesting with regard to scuba divers among whom there is a need to evaluate intraindividual ET function variability. Continuous impedance measurement in a pressure chamber was performed three times at one-week intervals between measurements. Twenty healthy participants (40 ears) were enrolled. Using a monoplace hyperbaric chamber, individual subjects were exposed to a standardised pressure profile consisting of a 20 kPa decompression over 1 min, a 40 kPa compression over 2 min, and a 20 kPa decompression over 1 min. Measurements of Eustachian tube opening pressure (ETOP), opening duration (ETOD), and opening frequency (ETOF) were made. Intraindividual variability was assessed. Mean ETOD during compression (actively induced pressure equalisation) on the right side was 273.8 (SD 158.8) ms, 259.4 (157.7) ms, and 249.2 (154.1) ms (Chi-square 7.30, P = 0.026) across weeks 1-3. Mean ETOD for both sides was 265.6 (153.3) ms, 256.1 (154.6) ms, and 245.7 (147.8) ms (Chi-square 10.00, P = 0.007) across weeks 1-3. There were no other significant differences in ETOD, ETOP and ETOF across the three weekly measurements. This longitudinal study suggests low week-to-week intraindividual variability of Eustachian tube function.

The Need for Emphasis on Intracranial Hypertension Management in Spontaneous Skull Base Meningoencephaloceles

To provide an analysis of patients with spontaneous skull base meningoencephaloceles (MECs) to determine whether definitive surgical treatment requires management of elevated intracranial pressure (ICP). Data of 10 subjects with spontaneous MECs were collected and retrospectively evaluated. Measurement of ICP, prior interventions, treatment with acetazolamide, and characteristics of long-term elevated ICP, among others, were analyzed. Our own indications for cerebrospinal fluid (CSF) diversion and use of postoperative external lumbar drain were analyzed as well. The sphenoid region was the most common location of MECs. CSF leak was diagnosed in all subjects. The most common graphical signs of elevated ICP were empty sella and arachnoid pits, both of which were present in 90% of cases. Lumbar puncture with opening pressure measurement was performed in 7 patients. Ventriculoperitoneal shunt insertion was indicated in 4 cases before skull base repair and in 2 cases after skull base repair. Two postoperative CSF leaks were managed with external lumbar drain and subsequent shunt installation. Spontaneous MECs are often associated with CSF leak. ICP assessment should be a standard of care to ensure successful operative repair of MECs. Insertion of a CSF diversion device must be considered where direct or indirect signs of intracranial hypertension are present.

Infantile idiopathic intracranial hypertension: case report and review of the literature

BackgroundIdiopathic intracranial hypertension is an infrequent condition of childhood, and is extremely rare in infants, with only 26 cases described. The etiology is still unknown. Typical clinical manifestations change with age, and symptoms are atypical in infants, thus the diagnosis could be late. This is based on increased opening pressure at lumbar puncture, papilloedema and normal cerebral MRI. The measurement of cerebrospinal fluid opening pressure in infants is an issue because many factors may affect it, and data about normal values are scanty. The mainstay of treatment is acetazolamide, which allows to relieve symptoms and to avoid permanent visual loss if promptly administered.Case presentationWe report the case of an 8-month-old infant admitted because of vomit, loss of appetite and irritability; later, also bulging anterior fontanel was observed. Cerebral MRI and cerebrospinal fluid analysis resulted negative and after two lumbar punctures he experienced initial symptom relief. Once the diagnosis of idiopathic intracranial hypertension was made, he received oral acetazolamide, and corticosteroids, with progressive symptom resolution.ConclusionsInfantile idiopathic intracranial hypertension is extremely rare, and not well described yet. Bulging anterior fontanel in otherwise healthy infants with normal neuroimaging should be always considered suggestive, but can be a late sign, while irritability and anorexia, especially if associated with vomiting, may represent an early sign. In such cases, lumbar puncture should be always done, hopefully with cerebrospinal fluid opening pressure measurement, which is among coded diagnostic criteria, but whose threshold is controversial in infants. Early diagnosis, timely treatment and strict follow-up help to prevent vision loss or death of affected infants.

Bilateral Optic Disc Edema in Multisystem Inflammatory Syndrome in Children Associated With COVID-19.

Bilateral Optic Disc Edema in Multisystem Inflammatory Syndrome in Children Associated With COVID-19.

A Unique Subset: Idiopathic Intracranial Hypertension Presenting as Spontaneous CSF Leak of the Anterior Skull Base.

Introduction Spontaneous cerebrospinal fluid (CSF) leaks represent a unique clinical presentation of idiopathic intracranial hypertension (IIH), lacking classical features of IIH, including severe headaches, papilledema, and markedly elevated opening pressures. Methods Following a single-institution retrospective review of patients undergoing spontaneous CSF leak repair, we performed a literature review of spontaneous CSF leak in patients previously undiagnosed with IIH, querying PubMed. Results Our literature review yielded 26 studies, comprising 716 patients. Average age was 51 years with 80.8% female predominance, and average body mass index was 35.5. Presenting symptoms included headaches (32.5%), visual disturbances (4.2%), and a history of meningitis (15.3%). Papilledema occurred in 14.1%. An empty sella was present in 77.7%. Slit ventricles and venous sinus stenosis comprised 7.7 and 31.8%, respectively. CSF leak most commonly originated from the sphenoid sinus (41.1%), cribriform plate (25.4%), and ethmoid skull base (20.4%). Preoperative opening pressures were normal at 22.4 cm H 2 O and elevated postoperatively to 30.8 cm H 2 O. 19.1% of patients underwent shunt placement. CSF leak recurred after repair in 10.5% of patients, 78.6% involving the initial site. A total of 85.7% of these patients were managed with repeat surgical intervention, and 23.2% underwent a shunting procedure. Conclusion Spontaneous CSF leaks represent a distinct variant of IIH, distinguished by decreased prevalence of headaches, lack of visual deficits, and normal opening pressures. Delayed measurement of opening pressure after leak repair may be helpful to diagnose IIH. Permanent CSF diversion may be indicated in patients exhibiting significantly elevated opening pressures postoperatively, refractory symptoms of IIH, or recurrent CSF leak.

Lumbar Puncture Opening Pressure in Patients with Spinal Muscular Atrophy

The announcement of a hydrocephalus as a possible side effect in patients with spinal muscular atrophy (SMA) receiving the drug nusinersen, promoted major concern and warrants further evaluation. In this retrospective monocentric study, we analyzed clinical data, lumbar puncture opening pressure (LOP) measurement, and ophthalmologic and neuroimaging results in 34 patients with SMA types 1 to 3 undergoing treatment with nusinersen. None of the patients reported symptoms indicative of increased intracranial pressure. In our cohort, the LOP was >20 cm H2O in 25 patients (70.5%), and within this group ≥28 cm H2O in 12 patients (35.3%), in two patients, it was increased prior to treatment initiation. Signs of increased intracranial pressure in ophthalmological assessments or brain imaging were only seen in one patient. We did not identify a correlation between increased LOP and SMA type, scoliosis, or age of the patients; however, it was slightly higher in patients receiving sedation. Our results raise the question whether the LOP is generally increased in SMA as part of the underlying disease, if so, what the etiology is, and whether the increased LOP needs to be treated.

Cryptococcosis.

Cryptococcosis has become an important infection in both immunocompromised and immunocompetent hosts. Although Cryptococcus is mainly recognized by its ability to cause meningoencephalitis, it can infect almost any organ of the human body, with pulmonary infection being the second most common disease manifestation. In cases of meningitis, symptom onset may be insidious, but headaches, fevers, or mental status changes should warrant diagnostic testing. Symptoms of pulmonary disease are nonspecific and may include fever, chills, cough, malaise, night sweats, dyspnea, weight loss, and hemoptysis. Due to protean manifestations of infection, diagnosis may be delayed or misdiagnosis may occur. Diagnosis typically is made by antigen testing of serum or cerebrospinal fluid or by culture or histopathology of infected tissues. A lumbar puncture with the measurement of opening pressure is recommended for patients with suspected or proven cryptococcosis. Treatment of cryptococcosis is based on the anatomical site of disease, severity of disease, and underlying immune status of the patient. Amphotericin B preparations plus 5-flucytosine is used as initial treatment of meningitis, disseminated infection, or moderate-to-severe pulmonary infection followed by fluconazole as a consolidation therapy. Fluconazole is effective for mild-to-moderate pulmonary infection. Important complications include elevated intracranial pressure and immune reconstitution syndrome, which may resemble active disease.

Transverse Sinus Stenosis in Refractory Chronic Headache Patients: An Observational Study.

Background: Transverse sinus stenosis is a common brain MRI finding in chronic migraine (CM) and chronic tension-type headache (CTTH) patients in clinical practice; however, its clinical and diagnostic role is unclear. The aim of the study is to determine the frequency of transverse sinus stenosis in these headache patients resistant to preventive treatments and to verify whether this is a useful finding for identifying patients with intracranial hypertension.Methods: This is an observational study. Patients with refractory CM and CTTH underwent a 3T-magnetic resonance venography (MRV) before cerebrospinal fluid (CSF) opening pressure measurement. Transverse sinus stenosis was determined using the combined conduit score. Patients with opening pressure >200 repeated MRV study 1 month after CSF withdrawal to evaluate changes in neuroimaging findings.Results: We analyzed MRV studies of 40 patients (32 F, 8 M; mean age, 49.4 ± 10.8; mean body mass index, 26.7 ± 6.4; 39 CM and 1 CTTH with concomitant episodic migraine). Nineteen cases (47.5%) had evidence of transverse sinus stenosis: bilateral in seven patients (17.5%) and unilateral in 12 cases (30%). No statistically significant differences in transverse sinus stenosis distribution were found between patients with opening pressure <200 mmH2O and those with opening pressure >200 mmH2O. On Spearman bivariate test, there was no correlation between opening pressure and combined conduit score. No changes in neuroimaging findings were found 1 month after CSF withdrawal.Conclusion: Transverse sinus stenosis is a frequent radiological finding (47.5%) in CM and CTTH patients refractory to preventive treatments. However, this finding is not suggestive of intracranial hypertension. Whether transverse sinus stenosis may be a possible risk factor for chronic headache or a comorbidity needs to be evaluated in larger epidemiological studies.

Comparison Of Digital Manometer And Water Column Manometer Pressures Measurements During Lumbar Puncture.

BackgroundCerebrospinal fluid (CSF) pressure measurement is routinely performed via a conventional water column manometer. There is increasing interest in using a digital manometer in measuring CSF pressures. The aim of this study is to compare column and digital manometers, in addition to measuring time to acquire the pressure readings.Research design and methodsThis prospective study included 27 patients who were referred for a fluoroscopically guided lumbar puncture. Opening pressure and closing pressure measurements were done with a digital manometer and then a traditional water column manometer. The time to obtain each pressure measurement was also recorded and compared.ResultsMean time to obtain pressure reading was significantly lower in the digital manometer group when compared to the water column manometer group (8.1 seconds vs. 42.2 seconds, P<0.05 for opening pressure and 8.92 seconds vs. 45.15 seconds, P<0.05 for closing pressure). Correlation between the opening pressure measurements (Pearson coefficient r= 0.98) and closing pressure (Pearson coefficient r= 0.89) was strong. However, the digital manometer reading consistently read higher.ConclusionDigital manometry during an LP yielded is faster however there might be a clinical difference between the devices. Clinicians must be careful in using the device across all cases.

Endoscopic transtympanic Eustachian tube dilatation: An overview of evaluation methods and dilatation technique.

Endoscopic technique in patients undergoing chronic ear surgery allows visualization of protympanic (proximal) segment of the Eustachian tube (ET). The proximal cartilaginous ET is a common site of anatomical Obstruction in chronic otitis media and it is this proximal end of ET that is being observed, instrumented and dilated with transtympanic methods. The aim of this article is to discuss our approach to the assessment of the Eustachian tube using opening pressure measurement, endoscopic assessment of the protympanic segment of ET and Valsalva CT. And also to discuss detailed technique of transtympanic Eustachian tube dilatation.

Prevalence of idiopathic normal pressure hydrocephalus: A prospective, population-based study.

BackgroundIdiopathic normal pressure hydrocephalus (iNPH) causing gait impairment, dementia and urinary incontinence among the elderly, is probably under-diagnosed and under-treated. Despite being known since the 1960s, there is still a lack of prospective, population-based studies on the prevalence of iNPH. Such studies are warranted to minimize selection bias and estimate the true prevalence of the disease.MethodsThe prevalence of iNPH was determined in a randomly selected sample of residents, aged 65 years and older, in the Swedish county of Jämtland. Out of 1,000 individuals invited to participate, 673 (67.3%) completed a questionnaire with seven questions on iNPH symptoms. A subgroup, with and without self-reported symptoms, participated in clinical and radiological evaluations and were diagnosed according to international guidelines. Measurement of cerebrospinal fluid opening pressure was not performed as it was considered too invasive.ResultsThose who reported at least two symptoms in the questionnaire (n = 117) and 51 randomly selected individuals with 0–1 symptom participated in further examinations. Out of them, 25 individuals received the diagnosis probable iNPH according to American-European guidelines (except for the criterion of CSF opening pressure) corresponding to a prevalence of 3.7%. The prevalence of iNPH was four times higher among those aged 80 years and older (8.9%) than among those aged 65–79 years (2.1%) (p <0.001). The difference in prevalence between men (4.6%) and women (2.9%) was not significant (p = 0.24). When iNPH was diagnosed according to the Japanese guidelines the prevalence was 1.5%ConclusionsIn this prospective, population-based study the prevalence of iNPH was 3.7% among individuals 65 years and older, and more common in the higher age group, 80 years and above. INPH should be increasingly recognized since it is a fairly common condition and an important cause of gait impairment and dementia among the elderly that can be effectively treated by shunt surgery.

Cryptococcosis in solid organ transplantation-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice.

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of cryptococcosis in the pre- and post-transplant period. The current update now includes a discussion of cryptococcosis, which is the third most common invasive fungal infection in SOT recipients. Infection often occurs a year after transplantation; however, early infections occur and donor-derived infections have been described within 3months after transplant. There are two main species that cause infection, Cryptococcus neoformans and Cgattii. Clinical onset may be insidious, but headaches, fevers, and mental status changes should warrant diagnostic testing. The lateral flow cryptococcal antigen assay is now the preferred test from serum and cerebrospinal fluid due to its rapidity, accuracy, and cost. A lumbar puncture with measurement of opening pressure is recommended for patients with suspected or proven cryptococcosis. Lipid amphotericin B plus 5-flucytosine is used as initial treatment of meningitis, disseminated infection, and moderate-to-severe pulmonary infection, followed by fluconazole as consolidation therapy. Fluconazole is effective for mild-to-moderate pulmonary infection. Immunosuppression reduction as part of management may lead to immune reconstitution syndrome that may resemble active disease.

Isolated cerebrospinal fluid hypertension in chronic headache: diagnostic innovations and clinical implications.

Isolated cerebrospinal fluid hypertension (ICH) is a condition of increased cerebrospinal fluid (CSF) pressure in the cranial-spinal compartment without an identifiable cause. Isolated headache is the most common symptom of ICH, while missing may be signs such as papilledema or sixth nerve palsy. This fact makes difficult the clinical diagnosis of headache attributable to ICH in headache sufferers. Another source of confusion stems from the CSF pressure measurement. It has been observed that a single-spot CSF opening pressure measurement may be insufficient to identify elevated CSF pressure in headache sufferers. A new method of CSF pressure measurement has been able to identify pressure-related features of isolated CSF hypertension (ICH). In fact, nocturnal or postural headache and abnormal pressure pulsations are the more common pressure-related features of ICH in patients with chronic headache. The compressive action of these abnormal pressure pulsations causes the periventricular white matter microstructure alterations leading to the focal diffusion tensor imaging findings in patients with ICH. Abnormal pressure pulsations are a marker of ICH in chronic headache. The identification of the CSF pressure-related features may be useful for differentiating headache sufferers with ICH from those with primary headache disorder in clinical practice. The therapeutic strategy in these headache sufferers with ICH includes the CSF removal and a medical treatment.

Feasibility and Safety of Transtympanic Balloon Dilatation of Eustachian Tube.

Assess safety and feasibility of transtympanic dilatation of proximal (tympanic-end) of the cartilaginous segment of the Eustachian tube in patients undergoing surgery for chronic ear disease. Case series. Tertiary care hospital. We reviewed the charts of 40 consecutive patients undergoing chronic ear surgery in our practice with manometric evidence of obstruction who underwent attempted transtympanic dilatation of proximal (tympanic-end) segment of the Eustachian tube. A range of outcome measures were reported that included pre and postdilatation opening pressure measurement of the Eustachian tube, closure of perforation, audiometric data, and complications. Dilatation of proximal (tympanic-end) of the cartilaginous segment of the Eustachian tube was technically feasible in 37 of 40 patients (93%). Postdilatation inspection of protympanum showed increased aperture in all dilated tubes. Opening pressure of Eustachian tube declined in 36 of 37 patients (97%). Residual perforation was evident in 5 of 40 patients (12%). No facial nerve or carotid complications were observed. Two patients had severe dizziness (5%) with one patient sustaining severe cochlear loss. Transtympanic dilatation increases the patency of the Eustachian tube immediately after instrumentation. No carotid complications were observed. Continuous endoscopic control is essential to avoid subluxation of stapes. Further study of this technique is warranted to identify its role, if any, in chronic ear surgery.

Idiopathic Intracranial Hypertension Without Papilledema (IIHWOP) in Chronic Refractory Headache.

Background: To determine the prevalence of Idiopathic intracranial hypertension without papilledema (IIHWOP) testing revised diagnostic criteria by Friedman in refractory chronic headache (CH) patients.Methods: This is a prospective observational study. Each patient underwent ophthalmologic evaluation and Optical Coherence Tomography; brain magnetic resonance venography (MRV) and a lumbar puncture (LP) with opening pressure (OP) measurement. CSF withdrawal was performed in patients with CSF OP > 200 mmH20. IIHWOP was defined according Friedman's diagnostic criteria. Effect of CSF withdrawal was evaluated clinically in a 6-month follow-up and with a MRV study at 1 month.Results: Forty-five consecutive patients were enrolled. Five were excluded due to protocol violations. Analyses were conducted in 40 patients (32 F, 8 M; mean age 49.4 ± 10.8). None had papilledema. Nine patients (22.5%) had OP greater than 200 mmH2O, two of them above 250 mmH2O. Two (5%) had neuroimaging findings suggestive of elevated intracranial pressure. One of them (2.5%) met the newly proposed diagnostic criteria by Friedman for IIHWOP. After CSF withdrawal seven (77.8%) of the nine patients improved. No changes in neuroimaging findings were found.Conclusions: We found a low prevalence (2.5%) of IIHWOP in refractory CH patients according to current diagnostic criteria. In agreement with Friedman's criteria, our results confirm that a diagnosis of IIHWOP should be based on CSF OP and the combination of neuroradiological findings. However, where to set the CSF OP upper limit in IIHWOP needs further field testing. Although IIHWOP is a rare clinical condition, it should be considered and treated in refractory CH patients.