Blood Pool Scintigraphy of the Skull in Relation to Head-Down Tilt Provocation in Patients With Chronic Tension-Type Headache and Controls

Laboratory tests of headache disorders – dawn of a new era?

Context

The classification of headache disorders has improved over the years, but further work is needed to develop and improve headache diagnosis within headache subtypes. The present review is a call for action to implement laboratory tests in the classification and management of primary and some secondary headaches.

Background

In this narrative review we present and discuss published tests that might be useful in phenotyping and/or diagnosis of long-lasting headache disorders such as migraine, tension-type headache, trigeminal autonomic cephalalgias, trigeminal neuralgia and persisting secondary headaches.

Aim

The palpometer test, quantitative sensory testing, nociceptive blink reflex and autonomic tests may be valuable to phenotype and/or diagnose subforms of migraine, tension-type headache, cluster headache, trigeminal neuralgia and medication-overuse headache. Provocation tests with glyceryl trinitrate (GTN) and calcitonin gene-related peptide (CGRP) may be valuable in subclassification of migraine and cluster headache. Lumbar pressure monitoring and optical coherence tomography may valuable tools to diagnose and follow patients with chronic headache and raised intracranial pressure.

Finding

A number of laboratory tests in headache research are presently available, but have primarily been performed in single research studies or a few studies that differ in methods and patient groups. At present, there is no evidence-based strategy for implementing diagnostic tests, but this could be achieved if well-reputed tertiary headache centers commence developing and implementing laboratory tests in order to improve the classification and treatment of headache patients.

Orbital phlebography in idiopathic intracranial hypertension and chronic tension-type headache

BACKGROUND

Pathologic signs in orbital phlebographies have been reported in various neurological diseases.

PURPOSE

To study if pathologic signs in orbital phlebography may be markers of inflammation primarily affecting intracranial capillaries, which would cause intracranial hypertension.

MATERIAL AND METHODS

Two groups with different intracranial cerebrospinal fluid pressures (Pcsf) were compared as to inflammatory markers in serum and pathologic signs in orbital phlebographies. Nine consecutive patients with idiopathic intracranial hypertension (IIH) with bilateral papilledema and eight consecutive patients with chronic tension-type headache (CTTH) were investigated prospectively with fibrinogen, orosomucoid, haptoglobin in serum, and invasive orbital phlebograms. The angiograms were evaluated by two skilled neuroradiologists, independent of each other and without knowledge of the diagnoses or aim of the study, as to the following pathologic signs: (i) narrowing of superior ophthalmic veins; (ii) caliber changes of intraorbital veins; (iii) collaterals of intraorbital veins; (iv) flow to cavernous sinus; and (v) asymmetric drainage of cavernous sinus.

RESULTS

Mean body mass index was >30 kg/m(2) in both groups. Pcsf was >200 < 250 mm H2O in 50% of the CTTH and >350 mm H2O in all IIH patients. No difference in inflammatory markers in blood was found. The phlebographies of the IIH patients had more pathologic signs and were considered pathologic significantly more often than the ones of the CTTH patients (P < 0.001).

CONCLUSION

The difference as to phlebographic pathologic signs between the IIH and the CTTH patients with different Pcsf supports the hypothesis that such phlebographic signs are markers of inflammation primarily affecting intracranial capillaries, which would disturb cerebrospinal fluid regulation causing intracranial hypertension.

The relationship between idiopathic intracranial hypertension and obesity

OBJECTIVE

Idiopathic intracranial hypertension (IIH) is usually considered to result from deficient intracranial absorption of cerebrospinal fluid, but has also been suggested to be caused by decreased cranial venous flow because of increased intrathoracic pressure resulting from intra-abdominal obesity. To test this hypothesis, cerebrospinal fluid pressure (Pcsf), extracranial venous pressure (Pvf), intracranial venous pressure, and body mass index (BMI) were studied in patients with IIH with papilledema compared with patients with chronic tension-type headache (CTTH).

DESIGN AND SUBJECTS

The Pcsf and the pressures in frontal veins without (Pvf) and with bilateral compression of the supraorbital branch of the frontal veins and the superficial facial veins (Pvfc), the latter considered to be about equal to Pvfc, were studied in 10 consecutive patients with IIH with papilledema. Ten consecutive CTTH patients were used for controls. Orbital phlebography was performed to confirm that the compression of facial veins other than the frontal veins resulted in adequate communication between the frontal vein used for the studies and the cavernous sinus.

RESULTS

Cerebrospinal fluid pressure was between 200 and 250 mm water in 5 of the CTTH patients and above 350 mm water in all IIH patients. Body mass index was >25 in all CTTH patients and similar in the 2 groups. Cerebrospinal fluid pressure was similar to Pvfc in all 10 CTTH patients but significantly greater in 6 of the 10 IIH patients. Pvf was similar in the 2 groups and related to BMI.

CONCLUSIONS

Chronic tension-type headache patients may be prone to have Pcsf > 200 mm water and BMI > 25. Papilledema because of intracranial hypertension occurred in the present study at Pcsf > 350 mm water. The findings of Pvfc and Pcsf being similar in all CTTH patients support the suggestion that the techniques used for measuring intracranial venous pressure are adequate. The findings of similar BMI in the CTTH and the IIH patients who differed significantly as to Pcsf refute the hypothesis that obesity precedes, and is the cause of, intracranial hypertension in IIH. The difference between Pcsf and Pvfc in 6 of the IIH patients also does not support such a hypothesis but may indicate that IIH is due to deficient intracranial cerebrospinal fluid absorption. Since a relationship between intracranial hypertension and obesity is established and obesity is not found to cause intracranial hypertension in IIH, intracranial hypertension may be suggested to be the primary cause of weight increase in IIH. Obesity, however, may secondarily increase the preexistent IIH.

From the nutcracker-phenomenon of the left renal vein to the midline congestion syndrome as a cause of migraine, headache, back and abdominal pain and functional disorders of pelvic organs

This paper presents the hypothesis, that pain and functional disturbances of organs which lie on the midline of the body might be caused by a venous congestion of these organs. Cause of their congestion is the participation of these organs (vertebral column, skull, brain, spinal medullary, uterus, prostate, left ovary/testis, urinary bladder rectum, vagina, urethra) in the collateral circulation of the left renal vein. In many patients with complaints of the above mentioned organs the left renal vein is compressed inside the fork formed by the superior mesenteric artery and the aorta. This so called nutcracker phenomenon is incompletely understood today. It can lead to a marked reduction of left renal perfusion and forces the left renal blood to bypass the venous compression site via abundant collaterals. These collaterals are often not sufficient. Their walls become stretched and distorted - varices with inflamed walls are formed. These dilated veins are painful, interfere with the normal organ's function and demand more space than usual. This way pain in the midline organs and functional derangement of the midline organs can occur. The term "midline congestion syndrome" seems appropriate to reflect the comprehensive nature of this frequent disorder. The rationale for this hypothesis is based on the novel PixelFlux-technique (www.chameleon-software.de) of renal tissue perfusion measurement. With this method a relevant decline of left renal cortical perfusion was measured in 16 affected patients before therapy (left/right ratio: 0.79). After a treatment with acetylsalicylic acid in doses from 15 to 200mg/d within 14-200 days a complete relief of so far long lasting therapy-resistant midline organ symptoms was achieved. Simultaneously the left/right renal perfusion ratio increased significantly to 1.24 (p=0.021). This improvement of left renal perfusion can be explained by a better drainage of collateral veins, diminution of their wall distension, thereby decline of their intramural inflammation, reduction of their mass effects (especially by the replaced spinal fluid inside the spinal canal and the skull), and altogether a reduction of pain and functional derangement in the affected midline organs. The proposed theory might influence the current understanding of such frequent and difficult to treat diseases as chronic back pain, headaches, frequent cystitis, enuresis, abdominal pain, flank pain and might spur new theories of arterial hypertension, placental insufficiency, prostate diseases and myelopathies.