Spontaneous intracranial hypotension results from cerebrospinal fluid leakage. Currently, the treatment of choice for spontaneous intracranial hypotension is the epidural blood patch, which has a variable response rate and no clear outcome predictors. This study aimed to identify predictors for response rate of a first targeted epidural blood patch in patients with spontaneous intracranial hypotension. We reviewed cases of patients with spontaneous intracranial hypotension who received targeted epidural blood patch at our hospital between 1 January 2007 and 1 July 2014. The outcome measure was first epidural blood patch response. We analysed demographics, clinical manifestations, neuroimaging findings (non-contrast heavily T-weighted magnetic resonance myelography and brain magnetic resonance imaging), and blood volume as potential outcome predictors. Significant predictors were tested and a decision tree was used to construct a predictive model. In total, 150 patients with spontaneous intracranial hypotension were included for final analyses. Their overall first targeted epidural blood patch response rate was 58.7%. Among patients with a greater injected blood volume (≥22.5 versus <22.5 ml), the response rate was higher (67.9% versus 47.0%, P = 0.01). In brain and spinal magnetic resonance imaging studies, significant predictors included anterior epidural cerebrospinal fluid collection length (<8 versus ≥8 segments; 72.5% versus 37.3%, odds ratio = 4.4, 95% confidence interval: 2.2-8.9, P < 0.001) and midbrain-pons angle (≥40° versus <40°; 71.3% versus 37.5%, odds ratio = 4.1, 95% confidence interval 2.1-8.3, P < 0.001). Decision tree analyses showed that patients with anterior epidural CSF collection involving <8 segments and an injected blood volume ≥22.5 ml had an 80.0% response rate. Patients with anterior epidural cerebrospinal fluid collection involving ≥8 segments and a midbrain-pons angle <40° had a 21.2% response rate. These three variables predicted first epidural blood patch response in 71.3% of patients. Brain and spinal neuroimaging findings and epidural blood patch blood volume can be used to predict targeted first epidural blood patch response in patients with spontaneous intracranial hypotension.

Objectives To compare the clinical profiles between male and female cluster headache patients from a large cohort. Methods This hospital-based study enrolled patients diagnosed with cluster headache between 1997 to 2021. Participants completed structured questionnaires collecting information on demographics, clinical profiles, and quality of life. Treatment regimens and effectiveness were determined through medical chart review. All variables were compared between the sexes. Results In total, 798 patients (M/F:659/139) were enrolled. The male-to-female ratio was 4.7:1 for the full study period, but it declined from 5.2:1 to 4.3:1 for patients enrolled before and after 2010, respectively. The frequencies of chronic cluster headache (M:1.2%, F:1.4%) and aura (M:0.3%, F:0.7%) were low but similar between the sexes. Most headache features showed no difference between men and women. Female patients had significantly longer attack duration, shorter inter-bout duration, higher frequencies for eyelid edema, nausea and vomiting and lower frequencies for conjunctival injection and pacing. Sex difference did not influence headache-associated disability, anxiety, or depression, but poor sleep quality was significantly more common in women. Among menstruating women, 22/122 (18.0%) reported worsening headaches during menses. The effectiveness of treatment was similar between the sexes. Conclusions Despite a decline of male-to-female ratio in the past two decades, most clinical profiles were similar between the sexes.

Objectives Several brain and spinal magnetic resonance imaging signs have been described in spontaneous intracranial hypotension. Their correlations are not fully studied. This study aimed to explore potential mechanisms underlying cerebral neuroimaging findings and to examine associations among spinal and brain magnetic resonance imaging signs. Methods We conducted a retrospective review of magnetic resonance myelography and brain magnetic resonance imaging records of patients with spontaneous intracranial hypotension. Categorical principal component analysis was employed to cluster brain neuroimaging findings. Spearman correlation was employed to analyze associations among different brain neuroimaging findings and between brain and spinal neuroimaging findings. Results In patients with spontaneous intracranial hypotension (n = 148), categorical principal component analysis of brain neuroimaging signs revealed two clusters: Cerebral venous dilation and brain descent. Among all brain magnetic resonance imaging signs examined, only midbrain-pons angle associated with anterior epidural cerebrospinal fluid collection length (surrogate spinal cerebrospinal fluid leak severity) (n = 148, Spearman’s ρ = −0.38, p < .001). Subgroup analyses showed that the association between midbrain-pons angle (within brain descent cluster) and spinal cerebrospinal fluid leak severity was presented in patients with convex margins of the transverse sinuses (n = 122, Spearman’s ρ = −0.43, p < .001), but not in patients without convex margins (n = 26, Spearman’s ρ = −0.19, p = .348). The association between severity of transverse sinus distension and spinal cerebrospinal fluid leak severity was only presented in patients without convex margins (n = 26, Spearman’s ρ = 0.52, p = .006). Conclusion This study indicates that there are two factors behind the brain neuroimaging findings in spontaneous intracranial hypotension: Cerebral venous dilation and brain descent. Certain brain neuroimaging signs correlate with spinal cerebrospinal fluid leakage severity, depending on different circumstances.

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.