The time sequence of brain MRI findings in spontaneous intracranial hypotension

Objectives To investigate the time sequence of brain magnetic resonance imaging findings of spontaneous intracranial hypotension. Methods We retrospectively reviewed the medical records and brain magnetic resonance imaging findings of consecutive patients with spontaneous intracranial hypotension hospitalized between January 2007 and December 2017. Patients were divided into quartiles based on intervals between initial spontaneous intracranial hypotension symptom onset and brain magnetic resonance imaging scan. Six categorical and five continuous brain magnetic resonance imaging findings were assessed, including venous distension sign, enlarged pituitary gland, diffuse pachymeningeal enhancement, mid-brain pons deformity, subdural fluid collection, flattening of pons, midbrain-pons angle, descent of cerebral aqueduct, mamillopontine distance, distance of suprasellar cistern, and distance of prepontine cistern. In addition, we also calculated the neuroimaging scores with a score ≥5 classified as ‘high probability of spontaneous intracranial hypotension' and a score ≥3 as ‘intermediate-to-high probability.' Then, we analyzed the linkage between the onset-neuroimaging interval and brain magnetic resonance imaging findings, as well as different neuroimaging scores. Results A total of 173 patients (57 males and 116 females) were included in the analysis, and the range of onset-neuroimaging interval was 1 to 89 days (median [interquartile range] = 17 [7 to 30 days]). We divided the patients into quartiles based on their onset-neuroimaging interval (the first quartile: 0–6 days; the second quartile: 7–16 days; the third quartile: 17–29 days; the fourth quartile: ≥30 days). Among brain magnetic resonance imaging findings, the incidence of venous distension sign was high (>75%), with no difference among quartiles (p = 0.876). The incidence of diffuse pachymeningeal enhancement (p = 0.001), severe midbrain-pons deformity (p = 0.001), and subdural fluid collection (<0.001) followed a significant stepwise increase from the first quartile to fourth quartile. Patients with shorter onset-neuroimaging intervals were less likely to have neuroimaging scores ≥5 (<17 vs. ≥17 days: 72.9% vs. 86.4%; odds ratio = 2.3 [95% CI 1.1–5.1], p = 0.028), but not neuroimaging scores ≥3 (<17 vs. ≥17 days: 92.9% vs. 92.0%, p = 0.824). Conclusions The emergence of brain magnetic resonance imaging findings of spontaneous intracranial hypotension depended on disease duration and appeared sequentially. When using brain magnetic resonance imaging findings or neuroimaging scores for diagnostic purposes, the onset–neuroimaging interval should be considered.

Spontaneous Intracranial Hypotension: Case Series of Rare Clinical Presentations

Background:Spontaneous intracranial hypotension (SIH) is an increasingly described entity, with over 70 cases reported in the literature. The classic triad includes orthostatic headache, diffuse pachymeningeal enhancement on magnetic resonance imaging (MRI) with gadolinium, and low cerebrospinal fluid pressure (CSF) in the lateral decubitus (<60 mm H2O) and sitting positions.Method:We present four rare clinical presentations of SIH, two of which have not been previously described in the literature, to the best of our knowledge.Results:Patient 1 presented with dyspnea, dysphagia, bilateral ptosis, diplopia and seizures. Patient 2 presented with a paradoxical positional pattern of orthostatic hypotension. In Patient 3, bilateral subdural hematomas (SDH) were encountered; while in Patient 4, a recurrent unilateral SDH requiring multiple surgical interventions was demonstrated.Conclusion:Although uncommon clinical presentations, all four cases of intracranial hypotension were spontaneous, demonstrated diagnostic MRI findings, and responded favorably to blood patches or saline injections.

The Timing of MRI Determines the Presence or Absence of Diffuse Pachymeningeal Enhancement in Patients with Spontaneous Intracranial Hypotension

The timing and clinical relevance of diffuse pachymeningeal enhancement (DPE) in the magnetic resonance imaging (MRI) examination of patients with spontaneous intracranial hypotension (SIH) remain undetermined. We reviewed 53 consecutive SIH patients (30 F/23 M, mean age of onset 41.7 ± 11.3 years) in a tertiary hospital. Thirteen (24.5%) patients did not have DPE on their initial cranial MRIs. They had significantly shorter latency between the time of MRI examinations and the time of headache onset compared with those with DPE (6.5 ± 4.4 vs. 20.4 ± 16.3 days, t-test, P < 0.001). Eight of these 13 patients received a follow-up MRI (mean duration 30.3 ± 16.6 days, range 6-59 days) and six of them revealed DPE. Among patients with DPE, the enhancement disappeared as early as 25 days after headache onset. The outcome did not differ between patients with and without DPE. The presence of DPE was associated with the timing of the MRI examination.

Postural Headache In A Patient With Marfan's Syndrome

A 26-year-old man with Marfan's syndrome had postural headache. Brain MRI with gadolinium showed diffuse pachymeningeal enhancement. MRI myelography revealed bilateral multiple large meningeal diverticula at sacral nerve roots level. He was suspected to have spontaneous intracranial hypotension syndrome. Eight days later headache improved with bed rest and hydration. One month after the onset he was asymptomatic and 3 months later brain MRI showed no evidence of diffuse pachymeningeal enhancement. The 1-year follow-up revealed no neurological abnormalities. The intracranial hypotension syndrome likely resulted from a CSF leak from one of the meningeal diverticula. In conclusion patients with spinal meningeal diverticula (frequently seen in Marfan's syndrome) might be at increased risk of developing CSF leaks, possibly secondary to Valsalva maneuver or minor unrecognizedtrauma.

Posture-Related Headaches and Pachymeningeal Enhancement in CSF Leaks from Craniotomy Site

Cerebrospinal fluid (CSF) leak is recognized to cause headaches that typically but not invariably have orthostatic features (present in upright posture, relieved by recumbency). Head magnetic resonance imaging (MRI) typically shows diffuse pachymeningeal enhancement. A 24-year-old woman, after resection of a right temporoparietal glioma, developed CSF leak from the craniotomy site, resulting in subgaleal fluid collection and associated with diffuse pachymeningeal gadolinium enhancement as well as posture-related headaches. The headaches, however, were present in a recumbent position and relieved after several minutes of being in an upright position. It is postulated that CSF leak took place when the patient was recumbent and ceased when she was upright, a position in which there is decrease in intracranial pressure. After cessation of the leak, along with disappearance of subgaleal collection of CSF, both the headaches and the pachymeningeal enhancement resolved.