Utility of intracranial pressure monitoring as a diagnostic tool in pediatric ventriculomegaly.

OBJECTIVE: Intracranial pressure (ICP) monitoring is commonly utilized for identifying pathologic ICP in cases of traumatic brain injury; however, its utility in hydrocephalic children has not been elucidated. Although patients with typical (pressure-active) hydrocephalus present with clear signs and/or symptoms and the need for cerebrospinal fluid (CSF) diversion is often clear, others may have arrested or pressure-compensated hydrocephalus with pathologic ICP elevation masked by ambiguous signs or are completely asymptomatic. Without treatment these pathologic ICP elevations may affect neurologic development or crescendo over time leading to neurological decline. The purpose of this study is to investigate the utility of ICP monitoring as a diagnostic tool in this relatively common patient population and identify ventriculomegaly patients with and without pathologic ICP, thus improving accuracy of identifying those with and without surgical needs. METHODS: 36 patients (≤ 17 years old) underwent 41 inpatient ICP recording sessions between 2016 and 2022 and were retrospectively reviewed. This included patients with a history of severe, nonprogressive ventriculomegaly and normal fundoscopic examinations lacking traditional signs and symptoms concerning for elevated ICP. Nighttime pathological plateau waves were defined as sustained elevations of ICP ≥ 2x baseline for a duration of ≥ 5 minutes. RESULTS: The mean age of patients was 5.5 years old (range 0-17 years old). 46.3% of patients had prior endoscopic third ventriculostomy (ETV), 14.6% had prior ventriculoperitoneal shunt (VPS), and 39% were without prior surgical intervention. Roughly half (51.2%) of patients had congenital ventriculomegaly while other patients had ventriculomegaly due to other pathologies such as germinal matrix hemorrhage/intraventricular hemorrhage (GMH/IVH) (29.3%), stroke (4.9%), cerebral infections/meningitis (2.4%), or unknown etiology (12.2%). The average procedure time was 19.1 ± 10.5 minutes, and mean length of stay was 2.8 ± 0.7 days. Pathologic ICP was demonstrated in 12 cases (29.3%), 4 (33.3%) of which were asymptomatic. Pathologic ICP was found in 7 of 19 (36.8%) in the prior ETV group, 1 of 6 (16.7%) in prior shunt group, and 4 of 16 (25%) in the non-surgical group (p = 0.649). Among those with pathologic ICP, 6 (50%) cases received an ETV, 5 (41.7%) cases underwent VPS placement, and 1 (8.3%) case underwent a VPS revision. There were no infectious complications or cases of hemorrhage. 4 patients required repositioning of the ICP monitor due to dislodgement. CONCLUSION: Inpatient ICP monitoring is a safe and effective diagnostic tool for evaluating the presence of pathologic ICP in severe, persistent non-progressive ventriculomegaly. The use of ICP monitoring may aid in identifying patients with pressure-compensated hydrocephalus who demonstrate pathologic ICP where surgical intervention may be warranted, while preventing unnecessary CSF diversion in those without pathology.

Foundations of the Diagnosis and Management of Idiopathic Intracranial Hypertension and Pulsatile Tinnitus.

Venous sinus stenosis has garnered increasing academic attention as a potential etiology of idiopathic intracranial hypertension (IIH) and pulsatile tinnitus (PT). The complex anatomy of the cerebral venous sinuses and veins plays a crucial role in the pathophysiology of these conditions. Venous sinus stenosis, often found in the superior sagittal or transverse sinus, can lead to elevated intracranial pressure (ICP) and characteristic IIH symptoms. Stenosis, variations in dural venous anatomy, and flow dominance patterns contribute to aberrant flow and subsequent PT. Accurate imaging plays a vital role in diagnosis, and magnetic resonance (MR) venography is particularly useful for detecting stenosis. Management strategies for IIH and PT focus on treating the underlying disease, weight management, medical interventions, and, in severe cases, surgical or endovascular procedures. Recently, venous sinus stenting has gained interest as a minimally invasive treatment option for IIH and PT. Stenting addresses venous sinus stenosis, breaking the feedback loop between elevated ICP and stenosis, thus reducing ICP and promoting cerebrospinal fluid outflow. The correction and resolution of flow aberrances can also mitigate or resolve PT symptoms. While venous sinus stenting remains an emerging field, initial results are promising. Further research is needed to refine patient selection criteria and evaluate the long-term efficacy of stenting as compared to traditional treatments.

[Diagnosis and treatment of spontaneous meningoencephalocele in lateral recess of sphenoid sinus and analysis of its influencing factors].

Objective:To explore the influencing factors of adult spontaneous meningoencephalocele, which occurs in the lateral recess of sphenoid sinus, in order to improve the level of clinical diagnosis and treatment. Methods:The clinical data of 27 adults with spontaneous meningoencephalocele in lateral recess of sphenoid sinus in Department of the Otorhinolaryngology, the First Affiliated Hospital of Zhengzhou University from January 2017 to December 2022 were retrospectively analyzed. Preoperative sinus CT and MRI were performed to confirm the diagnosis and location of meningoencephalocele. Results:①There were 0 cases of lateral recess of sphenoid sinus type Ⅰ, 8 cases of lateral recess of sphenoid sinus type Ⅱ and 19 cases of lateral recess of sphenoid sinus type Ⅲ. ②Among the 27 adult patients with spontaneous meningoencephalocele, 9 were male and 18 were female, and the onset age was 19-72 years old, with an average age of（50.7±12.4） years old. 18 cases were complicated with cerebrospinal fluid leakage, 11 cases with headache and dizziness, 3 cases with recurrent meningitis（complicated with cerebrospinal fluid leakage）, and 2 cases with epilepsy. ③There were 20 patients with intracranial hypertension, 17 patients with body mass index（BMI） ≥25 kg/m², and 8 patients with empty sella. Conclusion:Type Ⅲ of lateral recess of sphenoid sinus is the most common type in adult spontaneous meningoencephalocele, and intracranial hypertension and obesity are the influencing factors of this disease. Puncture, biopsy or operation should not be performed for patients suspected of spontaneous meningoencephalocele, and imaging examination should be performed to identify the source of the tumor.

Sex differences in the diagnostic value of optic nerve sheath diameter for assessing intracranial pressure.

The optic nerve sheath diameter (ONSD) can predict elevated intracranial pressure (ICP) but it is not known whether diagnostic characteristics differ between men and women. This observational study was performed at the Karolinska University Hospital in Sweden to assess sex differences in diagnostic accuracy for ONSD. We included 139 patients (65 women), unconscious and/or sedated, with invasive ICP monitoring. Commonly used ONSD derived measurements and associated ICP measurements were collected. Linear regression analyses were performed with ICP as dependent variable and ONSD as independent variable. Area under the receiver operator characteristics curve (AUROC) analyses were performed with a threshold for elevated ICP ≥ 20 mmHg. Analyses were stratified by sex. Optimal cut-offs and diagnostic characteristics were estimated. The ONSD was associated with ICP in women. The AUROCs in women ranged from 0.70 to 0.83. In men, the ONSD was not associated with ICP and none of the AUROCs were significantly larger than 0.5. This study suggests that ONSD is a useful predictor of ICP in women but may not be so in men. If this finding is verified in further studies, this would call for a re-evaluation of the usage and interpretation of ONSD to estimate ICP.

The current status of noninvasive intracranial pressure monitoring: A literature review.

Elevated intracranial pressure (ICP) is a life-threatening condition that must be promptly diagnosed. However, the gold standard methods for ICP monitoring are invasive, time-consuming, and they involve certain risks. To address these risks, many noninvasive approaches have been proposed. This study undertakes a literature review of the existing noninvasive methods, which have reported promising results. The experimental base on which they are established, however, prevents their application in emergency conditions and thus none of them are capable of replacing the traditional invasive methods to date. On the other hand, contemporary methods leverage Machine Learning (ML) which has already shown unprecedented results in several medical research areas. That said, only a few publications exist on ML-based approaches for ICP estimation, which are not appropriate for emergency conditions due to their restricted capability of employing the medical imaging data available in intensive care units. The lack of such image-based ML models to estimate ICP is attributed to the scarcity of annotated datasets requiring directly measured ICP data. This ascertainment highlights an active and unexplored scientific frontier, calling for further research and development in the field of ICP estimation, particularly leveraging the untapped potential of ML techniques.

Intracranial Hypertension Associated With Poly-Cranio-Radicular-Neuropathies: A Case Report and Review of the Literature.

INTRODUCTION: We present the case of a gentleman who developed rapidly progressive vision loss, ophthalmo-paresis, and flaccid quadriparesis in the context of severe intracranial hypertension. We reviewed the available cases in the literature to increase awareness of this rare clinical entity.Case Report:A 36-year-old man developed rapidly progressive vision loss, ophthalmo-paresis, and flaccid quadriparesis. He had an extensive workup, only notable for severe intracranial hypertension, >55 cm of H 2 O. No inflammatory features were present, and the patient responded to CSF diversion. Few similar cases are available in the literature, but all show markedly elevated intracranial pressure associated with extensive neuroaxis dysfunction. Similarly, these patients improved with CSF diversion but did not appear to respond to immune-based therapies. CONCLUSIONS: We term this extensive neuroaxis dysfunction intracranial hypertension associated with poly-cranio-radicular-neuropathy (IHP) and distinguish it from similar immune-mediated clinical presentations. Clinicians should be aware of the different etiologies of this potentially devastating clinical presentation to inform appropriate and timely treatment.

Idiopathic intracranial hypertension in two twin sisters.

Idiopathic intracranial hypertension (IIH) is a condition of unknown aetiology characterised by an increase in the intracranial pressure. Familial cases of IIH are rare and not well-understood. We present two monozygotic twins who developed IIH two years apart. The case involves two monozygotic female twins developing IIH in their 50s. They presented with a history of blurry vision and headaches. The diagnosis included the neurological, radiological and ophthalmological examination, excluding other causes. Both patients received treatment with acetazolamide, successfully resolving the papilloedema and restoring a normal visual field. This case highlights the occurrence of IIH among twins presenting at similar periods, emphasising the potential genetic influence. Clinicians should alert and educate the family regarding the risk factors and potential symptoms of this condition in the unlikely occurrence that other family members are affected.

A pilot clinical study to estimate intracranial pressure utilising cerebral photoplethysmograms in traumatic brain injury patients.

PURPOSE: In this research, a non-invasive intracranial pressure (nICP) optical sensor was developed and evaluated in a clinical pilot study. The technology relied on infrared light to probe brain tissue, using photodetectors to capture backscattered light modulated by vascular pulsations within the brain's vascular tissue. The underlying hypothesis was that changes in extramural arterial pressure could affect the morphology of recorded optical signals (photoplethysmograms, or PPGs), and analysing these signals with a custom algorithm could enable the non-invasive calculation of intracranial pressure (nICP). METHODS: This pilot study was the first to evaluate the nICP probe alongside invasive ICP monitoring as a gold standard. nICP monitoring occurred in 40 patients undergoing invasive ICP monitoring, with data randomly split for machine learning. Quality PPG signals were extracted and analysed for time-based features. The study employed Bland-Altman analysis and ROC curve calculations to assess nICP accuracy compared to invasive ICP data. RESULTS: Successful acquisition of cerebral PPG signals from traumatic brain injury (TBI) patients allowed for the development of a bagging tree model to estimate nICP non-invasively. The nICP estimation exhibited 95% limits of agreement of 3.8 mmHg with minimal bias and a correlation of 0.8254 with invasive ICP monitoring. ROC curve analysis showed strong diagnostic capability with 80% sensitivity and 89% specificity. CONCLUSION: The clinical evaluation of this innovative optical nICP sensor revealed its ability to estimate ICP non-invasively with acceptable and clinically useful accuracy. This breakthrough opens the door to further technological refinement and larger-scale clinical studies in the future. TRIAL REGISTRATION: NCT05632302, 11th November 2022, retrospectively registered.

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

BACKGROUND: Currently no guidelines for repeating a lumbar puncture to guide management in primary intracranial hypertension (PIH) exist. METHODS: An 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. RESULTS: Forty-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). CONCLUSIONS: This 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.

Spontaneous Cerebrospinal Fluid Leak in a Patient with Asymptomatic Idiopathic Intracranial Hypertension.

BACKGROUND: Spontaneous cerebrospinal fluid (CSF) leaks occur when there is a tear in the dura mater. Spontaneous CSF leaks are rare, and often associated with conditions like intracranial hypertension, connective tissue disorders, or congenital defects in the dura mater. CASE REPORT: The patient was a 66-year-old woman who presented to the Emergency Department with clear, positional nasal discharge from her left nostril for 1 week. She had a history of chronic headaches, which seemed to have been relieved around the time of onset of her rhinorrhea. Diagnostic imaging, including computed tomography and magnetic resonance imaging scans, confirmed the presence of a CSF leak and a left temporal meningoencephalocele. The patient subsequently underwent surgical repair of the leak and ventriculoperitoneal shunt placement, and was discharged home in stable condition. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Early detection of CSF leaks require a thorough history and physical examination, and is crucial in preventing potentially life-threatening complications such as meningitis and intracranial abscesses.

Advantages and Pitfalls of the Use of Optical Coherence Tomography for Papilledema.

PURPOSE OF REVIEW: Papilledema refers to optic disc swelling caused by raised intracranial pressure. This syndrome arises from numerous potential causes, which may pose varying degrees of threat to patients. Manifestations of papilledema range from mild to severe, and early diagnosis is important to prevent vision loss and other deleterious outcomes. The purpose of this review is to highlight the role of optical coherence tomography (OCT) in the diagnosis and management of syndromes of raised intracranial pressure associated with papilledema. RECENT FINDINGS: Ophthalmoscopy is an unreliable skill for many clinicians. Optical coherence tomography is a non-invasive ocular imaging technique which may fill a current care gap, by facilitating detection of papilledema for those who cannot perform a detailed fundus examination. Optical coherence tomography may help confirm the presence of papilledema, by detecting subclinical peripapillary retinal nerve fiber layer (pRNFL) thickening that might otherwise be missed with ophthalmoscopy. Enhanced depth imaging (EDI) and swept source OCT techniques may identify optic disc drusen as cause of pseudo-papilledema. Macular ganglion cell inner plexiform layer (mGCIPL) values may provide early signs of neuroaxonal injury in patients with papilledema and inform management for patients with syndromes of raised intracranial pressure. There are well-established advantages and disadvantages of OCT that need to be fully understood to best utilize this method for the detection of papilledema. Overall, OCT may complement other existing tools by facilitating detection of papilledema and tracking response to therapies.  Moving forward, OCT findings may be included in deep learning models to diagnose papilledema.

Systemic lupus erythematosus with chronic persistent intracranial hypertension: A case report.

OBJECTIVE: The aim is to investigate the clinical characteristics of systemic lupus erythematosus with intracranial hypertension. METHODS: The clinical characteristics of one case of systemic lupus erythematosus with chronic persistent intracranial hypertension were analyzed, and related literature was reviewed by searching Medline and Wanfang databases. RESULTS: Intracranial hypertension in SLE patients may occur at the onset or during the course of the disease. Our patient was diagnosed with IH 3 years after the onset of SLE. Headache and papilledema were the most common symptoms of intracranial hypertension, followed by nausea or vomiting, vision changes, and cerebral palsy. Our patient had a headache and cranial hypertension that lasted for years, but no papilledema was found. Corticosteroid is currently the mainstay of the treatment of IIH in patients with SLE, and immunosuppressive agents, acetazolamide, intravenous mannitol and furosemide are also used. However, our patient did not respond to these treatments and presents the characteristics of chronic persistent intracranial hypertension. CONCLUSION: Systemic lupus erythematosus with intracranial hypertension is a rare manifestation of SLE, which is not completely parallel to SLE activity. Headache and papilledema were the most common presenting symptoms. Different from previous reported cases, our patient had poor response to treatments, showing chronic and persistent characteristics.

Measurement of Optic Nerve Sheath Diameter by Computed Tomography in the Pediatric Population: Normal Values.

PURPOSE: To determine the normal values of optic nerve sheath diameter (ONSD) by computed tomography (CT) in the pediatric population. METHODS: The CT scans of pediatric patients aged 1 to 16 years who underwent brain CT for different reasons, who did not have intracranial pathology or increased intracranial pressure, and who had no pathology on CT were included in the study. Four age groups were defined with the following ranges: 1 to 2, 3 to 6, 7 to 10, and 11 to 16 years. ONSD was measured from axial CT images, 3 and 10 mm behind the optic globe. RESULTS: The normative values of ONSD measured on CT imaging in children aged 1 to 16 years were reported. The change in ONSD according to age was investigated. ONSD was found to increase with age at both levels measured. The difference was statistically significant. CONCLUSIONS: Normal values should be known to detect pathologies that may cause an increase in optic nerve diameter. The values reported in this study can serve as a reference for normal optic nerve sheath diameter in the pediatric age group. [J Pediatr Ophthalmol Strabismus. 2024;61(1):38-43.].

Evaluation of machine learning algorithms for noninvasive intracranial pressure estimation using near infrared spectroscopy as a covariate.

BACKGROUND: Intracranial pressure (ICP) is a vital parameter that is continuously monitored in patients with severe brain injury and imminent intracranial hypertension. OBJECTIVE: To estimate intracranial pressure without intracranial probes based on transcutaneous near infrared spectroscopy (NIRS). METHODS: We developed machine learning based approaches for noninvasive intracranial pressure (ICP) estimation using signals from transcutaneous near infrared spectroscopy (NIRS) as well as other cardiovascular and artificial ventilation parameters. RESULTS: In a patient cohort of 25 patients, with 22 used for model development and 3 for model testing, the best performing models were Fourier transform based Transformer ICP waveform estimation which produced a mean absolute error of 4.68 mm Hg (SD = 5.4) in estimation. CONCLUSION: We did not find a significant improvement in ICP estimation accuracy by including signals measured by transcutaneous NIRS. We expect that with higher quality and greater volume of data, noninvasive estimation of ICP will improve.

A multi-centre case series of patients with coexistent intracranial hypertension and malignant arterial hypertension.

OBJECTIVE: To describe the clinical characteristics, outcomes, and management of a large cohort of patients with concomitant malignant arterial hypertension and intracranial hypertension. METHODS: Design: Retrospective case series. SUBJECTS: Patients aged ≥ 18 years with bilateral optic disc oedema (ODE), malignant arterial hypertension and intracranial hypertension at five academic institutions. Patient demographics, clinical characteristics, diagnostic studies, and management were collected. RESULTS: Nineteen patients (58% female, 63% Black) were included. Median age was 35 years; body mass index (BMI) was 30 kg/m2. Fourteen (74%) patients had pre-existing hypertension. The most common presenting symptom was blurred vision (89%). Median blood pressure (BP) was 220 mmHg systolic (IQR 199-231.5 mmHg) and 130 mmHg diastolic (IQR 116-136 mmHg) mmHg), and median lumbar puncture opening pressure was 36.5 cmH2O. All patients received treatment for arterial hypertension. Seventeen (89%) patients received medical treatment for raised intracranial pressure, while six (30%) patients underwent a surgical intervention. There was significant improvement in ODE, peripapillary retinal nerve fibre layer thickness, and visual field in the worst eye (p < 0.05). Considering the worst eye, 9 (47%) presented with acuity ≥ 20/25, while 5 (26%) presented with ≤ 20/200. Overall, 7 patients maintained ≥ 20/25 acuity or better, 6 demonstrated improvement, and 5 demonstrated worsening. CONCLUSIONS: Papilloedema and malignant arterial hypertension can occur simultaneously with potentially greater risk for severe visual loss. Clinicians should consider a workup for papilloedema among patients with significantly elevated blood pressure and bilateral optic disc oedema.

Simple detecting of elevated ICP through liquor flow after lumbar puncture.

Elevated intracranial pressure (ICP) is defined as a cerebrospinal fluid (CSF) opening pressure (OP) greater than 25 cmH2O. When a diagnostic lumbar puncture is performed it is useful to estimate also intracranial pressure. To do this it is required a presence of pressure gauges, which are currently the gold standard, not available in most resource-constrained contexts. We decided to evaluate whether it is possible to estimate it simply by counting the drops of cerebrospinal liquor, which are collected after lumbar puncture, according to Poiseuille's law. Was examined a sample of 52 patients, aged between 18 and 85 years, belonging to the emergency room of "Santa Maria delle Grazie" Hospital in Pozzuoli (Naples) who needed a diagnostic lumbar puncture (LP). The ICP was initially measured using a standard narrow-gauge manometer by attaching it to the spinal needle. After removing the pressure gauge, the number of drops of cerebrospinal fluid flowing from the spinal needle in 30  seconds was counted. A statistical analysis was made with linear regression and ROC analysis. OP as measured by standard manometry was raised on 17 occasions with CSF drop rate median of 47 drops/30 seconds and range 30-74 drops/30 seconds. OP was normal on 35 occasions with CSF drop rate median of 23 drops/30 seconds  with range of 14-34 drops/30 seconds. A linear regression analysis was performed which resulted in a Pearson correlation of 0.936 an adjusted R square of 0.874 (see Fig. 1). Analysis through ANOVA documented an F of 355.301 with p < 0.01 and Dubin Watson of 1.642. The analysis through ROC showed an AUC of 0.980, with a sensitivity of 100% and a specificity of 91% if chosen as a limit, 29 drops in 30 seconds  (Youden Index of 0.9140). Therefore, we have concluded, that although there are several precautions, like patient's position, it is technically feasible to indirectly estimate cerebrospinal fluid pressure with good accuracy by counting the drops of cerebrospinal fluid flowing from a 22 G spinal needle.