Spontaneous Intracranial Hypotension Spontaneous CSF Leaks

Brainstem changes causing reversible RBD in patients with spontaneous intracranial hypotension: a longitudinal neuroimaging study

OBJECTIVE

This study aimed to investigate the prevalence of REM sleep behavior disorder (RBD) in patients with spontaneous intracranial hypotension (SIH) and longitudinally assess the effects of epidural blood patch (EBP) treatment on brainstem structures using a neuroimaging approach.

METHODS

Twenty-two participants (10 SIH patients and 12 controls) underwent 3-Tesla Magnetic Resonance Imaging (MRI) scans. Midbrain and pons areas were measured on T1-weighted scans at baseline in both groups and three months after the first EBP in SIH patients to determine any MRI structural changes. The RBD Single-Questionnaire was used to screen SIH patients with symptoms suggestive of RBD for polysomnographic (PSG) recording.

RESULTS

Half of the SIH patients (5/10) exhibited PSG-confirmed RBD. Baseline evaluation revealed deep brain swelling (DBS) on MRI scans in SIH-RBD patients. Following EBP treatment, significant changes in midbrain and pons morphometry were associated with complete clinical remission of RBD. Cross-sectional analysis showed larger midbrain and pons areas in SIH patients (with and without RBD) compared to controls. A midbrain area of 200 mm2 was identified as a cut-off value distinguishing SIH patients (with and without RBD) from controls individually. Longitudinal analysis demonstrated lower midbrain areas at follow-up compared to baseline in SIH patients.

DISCUSSION

The study suggests that brainstem morphometric changes may underlie reversible RBD in SIH patients. Midbrain area measurement could serve as a dynamic biomarker for SIH, particularly in the presence of RBD, offering insights for clinical practice.

Subdural Haematoma in Patients With Spontaneous Intracranial Hypotension

The incidence and clinical relevance of subdural haematoma (SDH) in patients with spontaneous intracranial hypotension (SIH) remain undetermined. We reviewed 40 consecutive SIH patients (18 female, 22 male) in a tertiary hospital. Eight (20%) of them had SDH and nine (23%), non-haemorrhagic subdural collections. The presence of SDH was associated with higher frequencies of male gender, recurrence of severe headache and neurological deficits. Outcomes were satisfactory after supportive care or epidural blood patches except for one SDH patient, who developed transtentorial herniation resulting in Duret haemorrhage and infarctions of bilateral posterior cerebral artery territories. In conclusion, subdural fluid collections were common in patients with SIH. SDH was associated with headache worsening or neurological deficits. Patients with SDH generally recovered well; however, serious sequela might occur.

Spinal imaging findings in spontaneous intracranial hypotension

OBJECTIVE

spontaneous intracranial hypotension is a syndrome of postural headaches that arises as a result of CSF leakage and without previous lumbar puncture. The purpose of this study was to review and describe the spinal imaging findings of this entity.

MATERIALS AND METHODS

The spinal MRI and CT myelographic imaging findings of 13 patients with spontaneous intracranial hypotension were retrospectively reviewed. Spinal images were evaluated for spinal fluid collections, dural enhancement, dilated epidural veins, a thickened or enlarged ventral lateral epidural venous plexus, high T2 signal intensity between the spinous processes of C1 and C2 (C1-C2 sign), structural abnormalities, canal attenuation or cord compression, and active contrast extravasation. When available, brain MRI findings were reviewed. Surgical correlation was made in the cases of four patients.

RESULTS

The patients were found to have spinal fluid collections (11 of 13 patients), dural enhancement (eight of 10 patients undergoing contrast administration), dilated epidural veins (10 of 13 patients), an enlarged epidural venous plexus (nine of 13 patients), C1-C2 sign (seven of 13 patients), structural abnormalities (four of 13 patients), canal attenuation or cord compression (five of 13 patients), and active contrast extravasation (four of 13 patients).

CONCLUSION

Spinal imaging is likely to show one or more findings in patients with spontaneous intracranial hypotension and may be of particular value to patients with equivocal clinical or brain imaging findings and patients who need surgery. Encountering these findings on spinal images may suggest the diagnosis of spontaneous intracranial hypotension and therefore can influence patient treatment.

Diet restriction in migraine, based on IgG against foods: a clinical double-blind, randomised, cross-over trial

Introduction: It is well-known that specific foods trigger migraine attacks in some patients. We aimed to investigate the effect of diet restriction, based on IgG antibodies against food antigens on the course of migraine attacks in this randomised, double blind, cross-over, headache-diary based trial on 30 patients diagnosed with migraine without aura.

Methods: Following a 6-week baseline, IgG antibodies against 266 food antigens were detected by ELISA. Then, the patients were randomised to a 6-week diet either excluding or including specific foods with raised IgG antibodies, individually. Following a 2-week diet-free interval after the first diet period, the same patients were given the opposite 6-week diet (provocation diet following elimination diet or vice versa). Patients and their physicians were blinded to IgG test results and the type of diet (provocation or elimination). Primary parameters were number of headache days and migraine attack count. Of 30 patients, 28 were female and 2 were male, aged 19–52 years (mean, 35 ± 10 years).

Results: The average count of reactions with abnormally high titre was 24 ± 11 against 266 foods. Compared to baseline, there was a statistically significant reduction in the number of headache days (from 10.5 ± 4.4 to 7.5 ± 3.7; P < 0.001) and number of migraine attacks (from 9.0 ± 4.4 to 6.2 ± 3.8; P < 0.001) in the elimination diet period.

Conclusion: This is the first randomised, cross-over study in migraineurs, showing that diet restriction based on IgG antibodies is an effective strategy in reducing the frequency of migraine attacks.

Expert Commentary: Role of Surgery for the Management of CSF Leaks

Spontaneous intracranial hypotension (SIH) was described nearly 70 years ago, and for years it was essentially equated with post dural puncture headaches (PDPH) (1). The interest in this entity substantially increased after the magnetic resonance imaging (MRI) abnormalities of this disorder were recognized in the early 1990s (2-6), and consequently many more patients were diagnosed than before and a far broader clinical spectrum of this disorder began to become apparent. It also came to be recognized that the overwhelming majority if not all cases of SIH result from spontaneous cerebrospinal (CSF) leaks and that the independent pathogenic parameter is loss of CSF volume (7).

Spontaneous intracranial hypotension with deep brain swelling

Spontaneous intracranial hypotension (SIH) is caused by leakage of CSF, and characterized on MRI by brain sagging, dilatation of veins and dural sinuses, subdural fluid collections and post-contrast enhancement of the thickened dura. A few cases may present a very severe brain sagging through the tentorial notch and swelling of the diencephalic-mesencephalic structures, with absent or scarce subdural collections and post-contrast enhancement. These patients may have surprisingly few neurological signs or may become drowsy and even lapse into coma due to central herniation. We retrospectively examined the diffusion studies obtained in five patients with these MRI findings, in seven patients with SIH without brain swellings and in ten controls. Mean diffusivity was increased in SIH patients with brain swelling in areas draining into the deep venous system, collected by the vein of Galen (vG) and straight sinus (SS). In the hypothesis that central herniation might be responsible for venous stagnation because of impaired flow of the vG into the SS, the vG/SS angle was measured. The angle formed by the vG entering the SS was not altered in patients without brain swelling (group E, 67.8 degrees +/- 10.3 degrees, mean +/- SD, range 49-80 degrees) when compared to controls (group C, 73.3 degrees +/- 12.3 degrees, mean +/- SD, range 56-95 degrees). It was, however, grossly decreased in patients with brain swelling (group D, 40.7 degrees +/- 12.8 degrees, mean +/- SD, range 22-61 degrees), P < 0.001 for comparison with groups E and C. As suggested by previous studies, downward stretching of the vG and narrowing of the vG/SS angle may cause a functional stenosis at the vG-SS junction. We suggest that in the application of the Monro-Kellie doctrine to SIH, the brain volume should not be considered as always invariable.