Update on intracranial hypertension and hypotension

Optical coherence tomography surpasses fundus imaging and intracranial pressure measurement in monitoring idiopathic intracranial hypertension

We aim to evaluate the retinal nerve fiber layer (RNFL) thickness measured with optical coherence tomography (OCT) in comparison with papilledema grade, and to assess the relationship between RNFL thickness, papilledema grade, and intracranial pressure (ICP) in idiopathic intracranial hypertension (IIH). Sixty-five patients with active IIH (AIIH) with papilledema, 39 with chronic IIH (CIIH) without papilledema and 80 healthy controls (HC) were examined with OCT and fundus imaging. RNFL thickness, papilledema grade and ICP level were assessed in 55 with AIIH and 26 with CIIH. RNFL thickness was significantly higher in AIIH compared to CIIH or HC. RNFL thickness correlated strongly with papilledema grade (coefficient 0.78, p < 0.01) and moderately with ICP (coefficient 0.569, p < 0.01). RNFL thickness was associated with papilledema progression (R2 = 0.656, p < 0.01): specifically, with increases of 9 µm from normal to mild grade (p > 0.05), 91 µm from normal to moderate (p < 0.01), and 214 µm from normal to severe (p < 0.01). ICP showed a weaker correlation with papilledema grades (R2 = 0.339, p < 0.05), with significant increase (8 cm H2O, p < 0.01) only from normal to severe papilledema. RNFL correlated strongly with papilledema grade and moderately with ICP levels. RNFL thickness increased proportionally per papilledema grade.

Optic nerve sonographic parameters in idiopathic intracranial hypertension, case-control study

The most common diagnostic error of IIH is inaccurate funduscopic examination. Moreover, IIH could be diagnosed without papilledema. Trans orbital sonography could be used as a non-invasive and cheap tool for discovering increased ICP (intracranial Pressure). Aim of our study was discovering the changes in ultra-sonographic indices and which one could predict the increased ICP. Sixty-eight patients were diagnosed as definite IIH and 68 healthy volunteers are included in the study who had the same sex and age. ONSD, peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were estimated by transorbital color Doppler. Multivariate linear regression was used to discover the predictors of increased ICP. ROC curve was plotted for the predictor. A statistically significant difference was found between IIH patients and controls regarding ONSD, EDV and RI. Multivariate linear regression revealed that ONSD is the only predictor of increased CSP pressure. Its cut-off value indicating high ICP was 5.7 mm on Rt and Lt eye (AUC: 0.916; 95% confidence interval 0.867-0.965; p < 0.001; 90% sensitivity, 80% specificity at Rt eye. AUC: 0.902; 95% confidence interval 0.845-0.958; p < 0.001; 91% sensitivity, 80% specificity at Lt eye).

Research productivity on spontaneous intracranial hypotension: A bibliometric analysis

Introduction

Spontaneous intracranial hypotension (SIH) is an important cause of devastating headaches and caused by CSF-leaks in the spine.

Research question

The aim of this analysis was to gain an overview of the progress of research on SIH over time. The global publication landscape relating to SIH was analyzed and comparisons between regions were made.

Material and methods

A bibliometric analysis was performed by searching for research articles on SIH in PubMed published between 1983 and 2022. Countries responsible for the publications were ranked by the sum of citations. An average annual growth rate was calculated and the density of SIH publications per 100 000 physicians was determined.

Results

We identified 974 articles. In 1983 only one SIH patient was reported; in 2021 the number of patients had increased to 4230. The average annual growth rate of SIH publications during this period was 12.7%. The most common publication type were case reports (n = 570). The most common medical specialty of the first author was neurology (n = 251) followed by neurosurgery (n = 250) and radiology (n = 191). Although most publications originated from the United States of America (USA), South Korea had the highest density of SIH investigators (37.86 publications per 100 000 medical doctors). The most cited paper (296 citations) was published in 2006 in JAMA (USA).

Discussion and conclusion

Research on SIH has increased exponentially over the past four decades. The international community of SIH researchers is growing, and with it the opportunities for global networks involved in research, treatment, and patient education.

Characterization of Ocular Sonography Findings and their Relationship to Clinical Features from a South Indian Cohort of Idiopathic Intracranial Hypertension

Background

Idiopathic intracranial hypertension (IIH) typically manifests with headache, accompanied by papilledema and visual loss, and has a higher prevalence in females. In recent years, ocular sonography, particularly, measurement of optic nerve sheath diameter (ONSD), is being investigated for diagnosis of IIH.

Methods

A total of 35 patients over the age of 18 years, fulfilling the modified Dandy's criteria for diagnosis of IIH were included. Patients underwent assessment with magnetic resonance imaging, lumbar puncture, and ocular sonography to measure ONSD and ocular arterial indices.

Results

The mean ONSD values (in centimeters) in the right eye of patients with IIH was 0.57 ± 0.13, while it was 0.48 ± 0.03 in controls. In the left eye, the mean ONSD value (cm) was 0.59 ± 0.13 in patients with IIH and 0.48 ± 0.03 in controls. ONSD was significantly higher in cases compared to controls (P < 0.001, Welch test). Pulsatility index of the central retinal artery was significantly higher in cases compared to controls (P < 0.001, Welch test). Resistance index of the ophthalmic artery was statistically significant (P < 0.005, Welch test). Receiver operating characteristic curve analysis revealed a cutoff value of 5.1 mm on the right side and 5 mm on the left side had a sensitivity and specificity of more than 80% for IIH diagnosis.

Conclusion

Our study provides insights into the utility of optic nerve sheath measurements and arterial indices in the diagnosis of IIH in a South Indian cohort. Further research is needed to fully understand the longitudinal relationship of these parameters and treatment outcomes in IIH.

Management of Complications in Vestibular Schwannoma Surgery

Microsurgical removal of acoustic neuroma has advanced tremendously; however, complications still occur. Facial nerve injury is the most common detrimental complication and should take precedence over gross tumor removal in cases where there is an unfavorable tumor-facial nerve interface. Cerebrospinal fluid leakage can occur even with meticulous closure techniques and is generally treatable with either lumbar-subarachnoid drainage or revision wound closure. Meningitis is a serious complication that requires a high index of suspicion in the postoperative period. Other less common complications include intraoperative and postoperative vascular injuries. Early identification and treatment can prevent devastating outcomes.

Spontaneous intracranial hypotension: from cerebral venous thrombosis to neurosurgical treatment: a case series experience from a Brazilian tertiary health care center

BACKGROUND

 Spontaneous intracranial hypotension (SIH) is a secondary cause of headache and an underdiagnosed disease. The clinical presentation can be highly variable. It typically presents with isolated classic orthostatic headache complaints, but patients can develop significant complications such as cerebral venous thrombosis (CVT).

OBJECTIVE

 To report 3 cases of SIH diagnosis admitted and treated in a tertiary-level neurology ward.

METHODS

 Review of the medical files of three patients and description of clinical and surgical outcomes.

RESULTS

 Three female patients with SIH with a mean age of 25.6 ± 10.0 years old. The patients had orthostatic headache, and one of them presented with somnolence and diplopia because of a CVT. Brain magnetic resonance imaging (MRI) ranges from normal findings to classic findings of SIH as pachymeningeal enhancement and downward displacement of the cerebellar tonsils. Spine MRI showed abnormal epidural fluid collections in all cases, and computed tomography (CT) myelography could determine an identifiable cerebrospinal fluid (CSF) leak in only one patient. One patient received a conservative approach, and the other two were submitted to open surgery with laminoplasty. Both of them had uneventful recovery and remission in surgery follow-up.

CONCLUSION

 The diagnosis and management of SIH are still a challenge in neurology practice. We highlight in the present study severe cases of incapacitating SIH, complication with CVT, and good outcomes with neurosurgical treatment.

Original technique of sealing cerebrospinal fluid leakage from dural sac causing spontaneous cerebral hypotension

Background:

Spontaneous intracranial hypotension (SIH) is a rare disease characterized by a decrease in the volume and pressure of cerebrospinal fluid (CSF) resulting from its leakage through the dura mater. SIH is curable, but it can lead to serious clinical sequelae or even death if not treated properly.

Case Description:

A 37-year-old female with headaches occurring in standing position and increasing especially during verticalization. Magnetic resonance imaging showed an image characteristic of SIH. Conservative treatment was applied in the form of bed rest. CT myelography scan located the site of CSF leakage. As the conservative treatment proved inefficient, it was decided to perform an epidural fistula sealing using the patient’s venous blood, administered under computed tomography guidance. The performed procedure completely resolved the patient’s complaints, allowing her to be discharged home.

Conclusion:

Patients with suspected SIH should remain in the supine position until a definitive diagnosis is made. Sealing the meningeal fistula with venous blood under computed tomography guidance should be considered in case of conservative treatment failure.

Optic Nerve Ultrasound Evaluation in Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) is a disease with a heterogeneity of possible causes, which needs to be quickly diagnosed. Ocular ultrasonography could be considered a useful tool to diagnose this condition in a fast and non-invasive way. In fact, Karl Ossoinig had already proposed this diagnostic tool in the 1970s for the evaluation of intracranial pressure changes under several pathological conditions, including idiopathic intracranial hypertension. The aim of this review is to analyze scientific articles published in the last 30 years concerning the use of ocular ultrasonography to assess optic nerve indices in patients with idiopathic intracranial hypertension. Specifically, 15 published articles found in PubMed database were included and analyzed in the present review. Our conclusion suggests that ocular ultrasonography is a reliable diagnostic technique to be utilized in all the cases of suspected raised intracranial pressure. To obtain the best possible accuracy and precision in the least invasive way, standardized A-scan seems to be the best choice.

Magnetic Resonance-Guided Diagnosis of Spontaneous Intracranial Hypotension in a Middle-Aged Woman

Spontaneous intracranial hypotension (SIH) is a rare condition caused by a cerebrospinal fluid (CSF) leak. It is diagnosed by clinical features that include an orthostatic headache combined with imaging findings demonstrating intracranial hypotension and a CSF leak. We present the case of a 45-year-old woman with an orthostatic headache who was found to have a sagging brain with a downward-displaced cerebellum and pachymeningeal enhancement with gadolinium contrast. This was initially misidentified as a Chiari I malformation, but the constellation of symptoms and MRI findings were later recognized as characteristic of SIH. Diagnosis of SIH and a CSF leak was confirmed with CT myelography. She was treated with a nontarget epidural blood patch, and her symptoms resolved. An orthostatic headache, a sagging brain, and pachymeningeal enhancement on MRI are highly specific for SIH, raising suspicion for this uncommon and often missed diagnosis.

Evaluation of 2D FLAIR hyperintensity of the optic nerve and optic nerve head and visual parameters in idiopathic intracranial hypertension

BACKGROUND AND PURPOSE

T2/FLAIR hyperintensity of the optic nerve/optic nerve head has been described as a sensitive finding in idiopathic intracranial hypertension using post-contrast 3D-T2/FLAIR imaging. The purpose of this study is to assess whether hyperintensity on non-enhanced 2D-T2/FLAIR imaging occurs more likely in diseased patients than controls and to evaluate the relationship between FLAIR signal and visual parameters MATERIALS AND METHODS: A retrospective case-control study was performed of patients with idiopathic intracranial hypertension and controls who underwent orbital MRI. Three neuroradiologists reviewed the FLAIR images, subjectively evaluating for hyperintense signal within the optic nerves/optic nerve heads using a 5-point Likert Scale. Quantitative assessment of optic nerve signal using regions of interests was performed. Clinical parameters were extracted. The diagnostic performance was evaluated, and Spearman correlation calculated to assess the relationship between FLAIR signal and visual outcomes.

RESULTS

The sensitivity of abnormal FLAIR signal within the optic nerves and optic nerve heads in patients with idiopathic intracranial hypertension ranged from 25-54% and 4-29%, respectively, with specificities ranging from 67-92% and 83-100%. Quantitative assessment revealed a significant difference in CNR between cases and controls in the left posterior optic nerve (p=.002). A positive linear relationship existed between abnormal optic nerve head signal and papilledema grade (OD: p=.02, OS: p=.008) but not with other visual parameters.

CONCLUSION

T2/FLAIR hyperintensity in the optic nerve/optic nerve head may support the diagnosis of idiopathic intracranial hypertension but its absence should not dissuade it. If present, abnormal signal in the optic nerve head correlates with papilledema.

Intracranial hypotension secondary to spontaneous spinal cerebrospinal fluid fistula: Three case reports

Spontaneous intracranial hypotension syndrome (SIH) is a rare condition. The main symptom is orthostatic headache, although other symptoms such as vegetative symptoms, meningism, or focal neurological deficits may appear. The most common cause is a cerebrospinal fluid leak, usually traumatic. Spontaneous cerebrospinal fluid leaks are rare and associated with the presence of meningeal cysts / diverticula or in the setting of connective tissue diseases. The diagnosis is based on imaging tests, both to detect intracranial complications and bilateral subdural hematomas and to locate the leak point at the intracranial or spinal level. The treatment of SIH is usually conservative: bed rest, caffeine and analgesics. Epidural blood patch is a good option when symptoms persist. Surgery is indicated in refractory cases or when there is an evident and accessible anatomic defect. This article describes three clinical cases with intracranial hypotension syndrome secondary to a spontaneous spinal cerebrospinal fluid leak.

An Update on Imaging in Idiopathic Intracranial Hypertension

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

Sonographic assessment of the optic nerve and the central retinal artery in idiopathic intracranial hypertension

PURPOSE

Transorbital sonography easily detects papilledema and enlarged optic nerve sheath diameters (ONSD) in IIH (idiopathic intracranial hypertension) patients. As the central retinal artery is located within the optic nerve, its hemodynamic properties might be affected by the increased pressure. In this study we assessed the diagnostic usefulness of transorbital sonography in IIH with a special focus on color Doppler imaging of the central retinal artery. IIH patients presented papilledema and enlarged ONSD. ONSD accurately predicted an increased intracranial pressure in IIH (cut-off: 5.8 mm, 81% sensitivity, 80% specificity). 24 h following therapeutic lumbar puncture ONSD diminished significantly, whereas papilledema was not changed. PSV (peak systolic velocity) and Vmean (mean flow velocity) of the central retinal artery were increased in IIH patients compared to controls. PSV accurately predicted an increase of intracranial pressure (cut-off: 11.0 cm/s, 70% sensitivity, 69% specificity). PI (pulsatility index), PSV and Vmean decreased following lumbar puncture. PSV and Vmean decreases were statistically significant for right eyes only in which the values changed to normal. In summary, besides ONSD enlargement and papilledema transbulbar sonography demonstrated an alteration of central retinal artery blood flow in IIH patients. Especially PSV might serve as valuable surrogate marker for intracranial pressure in IIH. Furthermore, the change of intra-individual central retinal arteries PI might be a valuable parameter to demonstrate response to lumbar puncture in IIH patients.

The effect of CSF drain on the optic nerve in idiopathic intracranial hypertension

Background

Elevation of intracranial pressure in idiopathic intracranial hypertension induces an edema of the prelaminar section of the optic nerve (papilledema). Beside the commonly observed optic nerve sheath distention, information on a potential pathology of the retrolaminar section of the optic nerve and the short-term effect of normalization of intracranial pressure on these abnormalities remains scarce.

Methods

In this exploratory study 8 patients diagnosed with idiopathic intracranial hypertension underwent a MRI scan (T2 mapping) as well as a diffusion tensor imaging analysis (fractional anisotropy and mean diffusivity). In addition, the clinical presentation of headache and its accompanying symptoms were assessed. Intracranial pressure was then normalized by lumbar puncture and the initial parameters (MRI and clinical features) were re-assessed within 26 h.

Results

After normalization of CSF pressure, the morphometric MRI scans of the optic nerve and optic nerve sheath remained unchanged. In the diffusion tensor imaging, the fractional anisotropy value was reduced suggesting a tissue decompression of the optic nerve after lumbar puncture. In line with these finding, headache and most of the accompanying symptoms also improved or remitted within that short time frame.

Conclusion

The findings support the hypothesis that the elevation of intracranial pressure induces a microstructural compression of the optic nerve impairing axoplasmic flow and thereby causing the prelaminar papilledema. The microstructural compression of the optic nerve as well as the clinical symptoms improve within hours of normalization of intracranial pressure.

Spontaneous intracranial hypotension and its complications

Spontaneous intracranial hypotension (SIH) is a syndrome that was unknown until the advent of magnetic resonance imaging (MRI). It is a cause of orthostatic headache, which remains underdiagnosed and, rarely, can result in several complications including dural venous sinus thrombosis, subdural hematoma and subarachnoid hemorrhage. Some of these complications are potentially life-threatening and should be recognized promptly, mainly by imaging studies. We reviewed the MRI of nine patients with SIH and describe the complications observed in three of these patients. Two of them had subdural hematoma and one had a dural venous sinus thrombosis detected by computed tomography and MRI. We concluded that MRI findings are of great importance in the diagnosis of SIH and its complications, which often influence the clinical-surgical treatment of the patient.

Iatrogenic Spinal Epidural Hematoma Associated with Intracranial Hypotension

Epidural steroid injections (ESIs) are one of the few modalities currently in use for treating chronic spinal pain. There are two approaches: interlaminar ESIs and transforaminal ESIs. Complications arising from either approach are rare, but one such complication is cerebrospinal fluid (CSF) leak leading to intracranial hypotension. Even rarer is the development of iatrogenic spinal epidural hematoma in the context of the injections. Interestingly, an association with intracranial hypotension and spinal epidural hematoma has yet to be established. Even the characteristics of an iatrogenic spinal epidural hematoma are not well defined as there are different theories of how this develops and whether we are dealing with arterial or venous blood. Our case is unique as it appears our patient had developed not one, but both clinical symptoms supportive of intracranial hypotension from a CSF leak induced iatrogenically from a cervical epidural injection and imaging demonstrated thoracic-level spinal epidural hematoma. It is unclear whether the injection directly led to the spinal leak causing the intracranial hypotension, which then brought on the formation of the hematoma or if the injection led to both intracranial hypotension and hematoma formation independent of each other. From a clinical practice standpoint, given our case suggests the hematoma was concomitantly associated with intracranial hypotension, and the possibility exists that the hematoma may have formed in the context of the intracranial hypotension, then targeted blood patches may need to be done with greater urgency to preventing hematoma formation. Further studies are needed involving clotting factors comparing arterial and venous blood. It is also puzzling why the epidural blood from the hematoma did not clot the leak. This concomitancy deserves further attention and may lead to changes in how we manage cervical epidural injection patients who are found to have CSF leak and a spinal epidural hematoma.

Nonmigraine Headache and Facial Pain

The vast majority of headache patients encountered in the outpatient general medicine setting will be diagnosed with a primary headache disorder, mostly migraine or tension-type headache. Other less common primary headaches and secondary headaches, related to or caused by another condition, are the topic of this article. Nonmigraine primary headaches include trigeminal autonomic cephalalgias, primarily cluster headache; facial pain, primarily trigeminal neuralgia; and miscellaneous headache syndromes, such as hemicrania continua and new daily persistent headache. Selected secondary headaches related to vascular disease, cerebrospinal fluid dynamics, and inflammatory conditions are also reviewed.

European headache federation guideline on idiopathic intracranial hypertension

Background

Idiopathic Intracranial Hypertension (IIH) is characterized by an elevation of intracranial pressure (ICP no identifiable cause. The aetiology remains largely unknown, however observations made in a number of recent clinical studies are increasing the understanding of the disease and now provide the basis for evidence-based treatment strategies.

Methods

The Embase, CDSR, CENTRAL, DARE and MEDLINE databases were searched up to 1st June 2018. We analyzed randomized controlled trials and systematic reviews that investigate IIH.

Results

Diagnostic uncertainty, headache morbidity and visual loss are among the highest concerns of clinicians and patients in this disease area. Research in this field is infrequent due to the rarity of the disease and the lack of understanding of the underlying pathology.

Conclusions

This European Headache Federation consensus paper provides evidence-based recommendations and practical advice on the investigation and management of IIH.

Electronic supplementary material

The online version of this article (10.1186/s10194-018-0919-2) contains supplementary material, which is available to authorized users.

Spontaneous intracranial hypotension: two steroid-responsive cases

Purpose

Spontaneous intracranial hypotension (SIH) is characterised by orthostatic headache, low cerebrospinal fluid pressure and diffuse pachymeningeal enhancement after intravenous gadolinium contrast administration. Magnetic resonance imaging (MRI) often plays a crucial role for correct diagnosis.

Case description

We described two similar cases of SIH, whose clinical and imaging features are typical for this pathology. At MRI brain scan, both patients showed diffuse and intense pachymeningeal enhancement and moderate venous distension and epidural vein engorgement. The two patients were treated with bed rest and oral steroid therapy, with complete and long-lasting symptomatic relief.

Conclusions

Orthostatic nature of headache is the most indicative clinical feature suggesting SIH; contrast-enhanced MRI provides definite imaging diagnostic findings. Conservative treatment coupled to steroid therapy is often sufficient to obtain complete disappearance of symptoms.

Impaired cerebrospinal fluid pressure

Abnormalities of cerebrospinal fluid (CSF) pressure are relatively common and may lead to a variety of symptoms, with headache usually being the most prominent one. The clinical presentation of alterations in CSF pressure may vary significantly and show a striking similitude to several primary headache syndromes. While an increase in CSF pressure may be of primary or secondary origin, a pathologic decrease of CSF pressure is usually the result of a meningeal rupture with a resulting leakage of CSF. The pathophysiologic mechanisms of idiopathic intracranial hypertension (IIH) remain largely unknown. However recent evidence indicates that an abnormality in CSF outflow and absorption is likely to play a significant role. Treatment usually consists of a combination of weight loss and a pharmacologic approach using carbonic anhydrase inhibitors. Recent results of the first randomized, double-blind, placebo-controlled trial (RCT) with acetazolamide proved its efficacy in reducing headache and visual disturbances. Clinical evidence suggests efficacy for topiramate and furosemide but no RCT has been conducted to date to confirm these results. In contrast to IIH, spontaneous intracranial hypotension frequently remits spontaneously without specific treatment. If necessary, treatment options range from conservative methods to epidural blood or fibrin sealant patches and surgical interventions.

The Glymphatic Pathway: Waste Removal from the CNS via Cerebrospinal Fluid Transport

The overall premise of this review is that cerebrospinal fluid (CSF) is transported within a dedicated peri-vascular network facilitating metabolic waste clearance from the central nervous system while we sleep. The anatomical profile of the network is complex and has been defined as a peri-arterial CSF influx pathway and peri-venous clearance routes, which are functionally coupled by interstitial bulk flow supported by astrocytic aquaporin 4 water channels. The role of the newly discovered system in the brain is equivalent to the lymphatic system present in other body organs and has been termed the "glymphatic pathway" or "(g)lymphatics" because of its dependence on glial cells. We will discuss and review the general anatomy and physiology of CSF from the perspective of the glymphatic pathway, a discovery which has greatly improved our understanding of key factors that control removal of metabolic waste products from the central nervous system in health and disease and identifies an additional purpose for sleep. A brief historical and factual description of CSF production and transport will precede the ensuing discussion of the glymphatic system along with a discussion of its clinical implications.

Murine hypothalamic destruction with vascular cell apoptosis subsequent to combined administration of human papilloma virus vaccine and pertussis toxin

Vaccination is the most powerful way to prevent human beings from contracting infectious diseases including viruses. In the case of the human papillomavirus (HPV) vaccine, an unexpectedly novel disease entity, HPV vaccination associated neuro-immunopathetic syndrome (HANS), has been reported and remains to be carefully verified. To elucidate the mechanism of HANS, we applied a strategy similar to the active experimental autoimmune encephalitis (EAE) model - one of the most popular animal models used to induce maximum immunological change in the central nervous system. Surprisingly, mice vaccinated with pertussis toxin showed neurological phenotypes that include low responsiveness of the tail reflex and locomotive mobility. Pathological analyses revealed the damage to the hypothalamus and circumventricular regions around the third ventricle, and these regions contained apoptotic vascular endothelial cells. These data suggested that HPV-vaccinated donners that are susceptible to the HPV vaccine might develop HANS under certain environmental factors. These results will give us the new insight into the murine pathological model of HANS and help us to find a way to treat of patients suffering from HANS.

Idiopathic intracranial hypertension eliminated by counterclockwise maxillomandibular advancement: a case report

INTRODUCTION

Obstructive sleep apnea (OSA) is a secondary cause of intracranial hypertension (IH). Decreased jugular venous drainage has been seen in patients with idiopathic IH.

CLINICAL PRESENTATION

A complex case of a 48-year-old female whose idiopathic IH was put into remission after counterclockwise maxillomandibular advancement (CC-MMA), despite persistence of her OSA.

CONCLUSION

This case highlights the relationship between OSA and IH and points to the significant morbidity that can result from mild OSA and from what are considered borderline intracranial pressures. This indicates the need for a high index of suspicion for actual underlying pathology that can be surgically corrected when patients manifest symptoms of a somatic syndrome. This is the first report in the medical literature of clinical elimination of IH by CC-MMA. The authors propose that this positive outcome was effected via mandibular advancement producing a decrease in jugular venous resistance, allowing improved absorption of cerebrospinal fluid.

Bilateral Abducens Nerve Palsy due to Idiopathic Intracranial Hypertension as an Initial Manifestation of Systemic Lupus Erythematosus

Idiopathic intracranial hypertension (IIH) is a syndrome of increased intracranial pressure and presents as an intractable headache, vomiting, and ophthalmologic manifestations. We herein report the case of a young girl who presented with bilateral abducens nerve palsy due to IIH as the onset of systemic lupus erythematosus (SLE). The patient was successfully treated with corticosteroid therapy. Our case lacked the typical symptoms of IIH, such as headache or nausea; therefore, it is necessary to carefully determine the cause of bilateral abducens nerve palsies. The development of IIH in SLE patients is a rare occurrence, but this manifestation should not be overlooked.

[Cerebrospinal fluid leakage. Indications, technique and results of treatment with a blood patch]

BACKGROUND

In most cases cerebrospinal fluid (CSF) leaks are iatrogenic and caused by medical interventions, such as lumbar puncture, peridural anesthesia and surgical interventions on the spine, However, spontaneous cerebral hypotension is currently detected more frequently due to improvements in diagnostic possibilities but often the cause cannot be clarified with certainty.

METHODS

There are various diagnostic tools for confirming the diagnosis and searching for the site of CSF leakage, such as postmyelography computed tomography (postmyelo-CT), indium(111) radioisotope cisternography and (myelo) magnetic resonance imaging (MRI), which show different sensitivities. In accordance with own experience native MRI with fat-saturated T2-weighted sequences is often sufficient for diagnosing CSF leakage and the site. For the remaining cases an additional postmyelo-CT or alternatively myelo-MRI is recommended. In some patients with spontaneous cranial hypotension multiple CSF leaks are found at different spinal levels. The main symptom in most cases is an orthostatic headache. While post-puncture syndrome is self-limiting in many cases, spontaneous CSF leakage usually requires blood patch therapy. A lumbar blood patch can be safely carried out under guidance by fluoroscopy. In the case of a cervical or dorsal blood patch, CT guidance is recommended, which ensures epidural application of the blood patch and minimizes the risk of damaging the spinal cord. Despite a high success rate at the first attempt with a blood patch of up to 85%, some cases require repeating the blood patch. A targeted blood patch of a CSF leak should generally be favoured over a blindly placed blood patch; nevertheless, if a CSF leak cannot be localized by CT or MRI a therapeutic attempt with a lumbar blood patch can be carried out. After a successful blood patch intracranial hygromas and pachymeningeal enhancement in the head show fast regression; however, epidural hygromas of the spine can persist for a period of several months, even though patients are already free of symptoms.

CONCLUSION

In total, blood patch therapy is a safe and technically relative simple method with a high success rate. Therefore, it represents the therapy of choice in patients with spontaneous cerebrospinal fluid leakage as well as in cases of post-lumbar puncture syndrome refractory to conservative therapy.

Spontaneous intracranial hypotension presenting as thunderclap headache: a case report

Background

Spontaneous intracranial hypotension is a rare but treatable cause of a disabling headache syndrome. It is characterized by positional orthostatic headache, pachymeningeal enhancement and low cerebrospinal fluid pressure. However, the spectrum of clinical and radiographic manifestations is varied and misdiagnosis is common even in the modern era of magnetic resonance imaging. Spontaneous intracranial hypotension presenting as thunderclap headache is recognized but rare.

Case presentation

A 41-year-old Sri Lankan female presented with thunderclap headache associated with nausea and vomiting, but the headache was characterized by positional variation with aggravation in the upright posture and relief in the supine posture. Gadolinium-enhanced cranial magnetic resonance imaging demonstrated generalized meningeal enhancement and normal magnetic resonance angiography while lumbar puncture revealed a cerebrospinal fluid opening pressure of less than 30 millimetres of water. Magnetic resonance myelography failed to identify the site of cerebrospinal fluid leak. The patient was managed conservatively with bed-rest, intravenous hydration, analgesics and an increased intake of oral coffee which led to a gradual relief of headaches in the upright posture.

Conclusions

Spontaneous intracranial hypotension can rarely present as thunderclap headache. Awareness of its varied spectrum of presentations would avoid inappropriate investigations, misinterpretation of imaging results and ineffective treatment.

[Intracranial hypertension and jugular vein thrombosis]

BACKGROUND

Pseudotumor cerebri is an idiopathic increase in intracranial pressure, which commonly affects obese women of fertile age. The diagnostic criteria according to the guidelines of the German Society for Neurology are increased cerebrospinal fluid (CSF) pressure, symptoms of increased CSF pressure, normal results of CSF examination, no relevant medication and a lack of structural and vascular lesions in magnetic resonance imaging (MRI).

CASE REPORT

This article presents the case of a 39-year-old male patient who presented at hospital with visual obscuration and recently occurred double vision. Except for a recently diagnosed thrombosis of the left jugular vein of unknown origin, there was nothing else of note in the medical history. Biomicroscopic examination showed papilledema with hemorrhages and cotton wool spots. The CSF opening pressure was initially > 50 cmH2O. During therapy by lumbar puncture (three times), oral carbonic anhydrase inhibitors and loop diuretics, the abducens nerve palsy and papilledema receded. Anticoagulation therapy (initially with coumarin derivatives, then with low molecular weight heparins) was unsuccessful in eliminating the thrombosis of the jugular vein. Surgical intervention was not recommended by the vascular surgeons.

CONCLUSION

This case report demonstrates the unusual combination of (idiopathic) intracranial hypertension and thrombosis of the jugular vein, which occurred spontaneously and without any detectable coagulation disorders.

[Pseudotumor cerebri syndrome]

Pseudotumor cerebri is a non-tumor related idiopathic or secondary intracranial hypertension. It is typically associated with papilledema and headache and patients are typically female, young and obese. Diagnosis is established by neuroimaging by magnetic resonance imaging (MRI), cerebral MR venography (MRV) and lumbar puncture. Papilledema is assessed by ophthalmoscopy, ultrasound and optical coherence tomography. Ophthalmologists monitor visual function by measuring visual acuity and visual field testing. Therapy of patients not facing immediate visual loss encompasses weight reduction and administration of carbonic anhydrase inhibitors. In vision-threatening situations invasive procedures are necessary, such as repeated lumbar puncture, liquor drainage, optic nerve sheath fenestration and endovascular venous stenting.

Hypertrophic pachymeningitis associated with cerebral spinal fluid hypovolemia as initial presentation of systemic lupus erythematous

We report a case of a 61-year-old man with thickening of the dura mater associated with the presence of subdural collections as a consequence of cerebral spinal fluid hypovolemia (CSFH) and hypertrophic pachymeningitis (HP) as presentation of systemic lupus erythematous (SLE). The patient complained about fatigue, musculoskeletal pain, headache and skin lesions. In the laboratory tests minimal normocytic anemia, mild leukopenia, polyclonal hypergammaglobulinemia and antinuclear antibodies (ANA), anti-double-stranded DNA antibodies (dsDNA), antibodies against extractable nuclear antigens (ENA) type SSA-Ro, anti-Smith antigen antibodies (anti-Sm) and anti-ribonucleoprotein antibodies (anti-RNP) were detected. Cranial magnetic resonance imaging (MRI), with and without gadolinium enhancement, revealed generalized thickening of the dura mater more severe at the right parieto-occipital lobes with the presence of subdural collections. The patient was diagnosed with SLE associated both with CSFH and HP. A conservative treatment with prednisone 60 mg daily, mycophenolate mofetil (MMF) 1 g daily and hydroxychloroquine 200 mg twice a day was started with significant clinical and radiological improvement (almost complete resolution of the subdural collections and clear decrease of meningeal thickness).

The authors emphasize that HP associated with CSFH in the context of SLE is a rare entity, which makes this case unique.

A novel rat model to study the role of intracranial pressure modulation on optic neuropathies

Reduced intracranial pressure is considered a risk factor for glaucomatous optic neuropathies. All current data supporting intracranial pressure as a glaucoma risk factor comes from retrospective and prospective studies. Unfortunately, there are no relevant animal models for investigating this link experimentally. Here we report a novel rat model that can be used to study the role of intracranial pressure modulation on optic neuropathies. Stainless steel cannulae were inserted into the cisterna magna or the lateral ventricle of Sprague-Dawley and Brown Norway rats. The cannula was attached to a pressure transducer connected to a computer that recorded intracranial pressure in real-time. Intracranial pressure was modulated manually by adjusting the height of a column filled with artificial cerebrospinal fluid in relation to the animal’s head. After data collection the morphological appearance of the brain tissue was analyzed. Based on ease of surgery and ability to retain the cannula, Brown Norway rats with the cannula implanted in the lateral ventricle were selected for further studies. Baseline intracranial pressure for rats was 5.5±1.5 cm water (n=5). Lowering of the artificial cerebrospinal fluid column by 2 cm and 4 cm below head level reduced ICP to 3.7±1.0 cm water (n=5) and 1.5±0.6 cm water (n=4), a reduction of 33.0% and 72.7% below baseline. Raising the cerebrospinal fluid column by 4 cm increased ICP to 7.5±1.4 cm water (n=2) corresponding to a 38.3% increase in intracranial pressure. Histological studies confirmed correct cannula placement and indicated minimal invasive damage to brain tissues. Our data suggests that the intraventricular cannula model is a unique and viable model that can be used to study the effect of altered intracranial pressure on glaucomatous optic neuropathies.