Similar to conventional radiography, X-rays are generated using an X-ray tube, captured on the opposite side of the body by a special detector and then converted into a video signal so that moving images can be viewed on the screen. In contrast to other imaging procedures for vascular visualisation (computer tomography or magnetic resonance imaging), small interventions can also be carried out in the same examination.
These include, for example
- visualisation of neck and brain vessels
- Vascular opening measures for the treatment of vascular stenoses caused by vascular calcifications or soft wall deposits (balloon dilatation, stent placement, lysis of thrombi)
- Vessel-closing measures, e.g. to eliminate vascular dilatations (aneurysms) and vascular malformations by means of coiling
- Treatment of vascular injuries
- Tumours can be treated directly and selectively on site with therapeutic medication or the supplying vessels can be closed before an operation.
Diagnostic angiography of the cerebral vessels
Interventional angiography - vessel-opening measures
Interventional neuroradiology has established itself as a highly specialised field for the endovascular treatment of vascular diseases of the central nervous system. In this context, vascular-opening measures have been developed, for example to restore blood flow in acute strokes, and vascular-closing measures, for example to treat aneurysms in acute subarachnoid haemorrhage.
Case studies Vascular opening measures
The insertion of stents into a carotid artery that is narrowed with calcified or soft deposits is a therapeutic alternative to surgical treatment of the stenosis in many cases today.
The examination is planned using computed tomography (angio-CT), which visualises the stenosis and the anatomical conditions of the arterial neck and brain vessels.
In the angiography, a catheter is advanced into the carotid artery via a sheath in the groin area, through which the stent is placed in the stenosis and then expanded.
The final check-up and further monitoring of the stent are again carried out using an angio-CT scan.
A 40-year-old female patient presented with increasing clouding of consciousness after a gastrointestinal infection. CT showed the rectus sinus as well as the internal cerebral veins to be hyperdense. The MRI showed bithalamic oedema. The changes are typical for an internal cerebral vein thrombosis.
Angiography showed the entire internal cerebral venous system, V. Galeni, right rectus sinus and right transverse sinus, to be occluded when the left vertebral artery was injected.
As the symptoms rapidly worsened despite systemic intravenous heparinisation, local thrombolysis was indicated. For this purpose, a transfemoral (venous) microcatheter was inserted through the thrombus into the internal cerebral venous system.
Since local intravenous lysis is carried out over a long period of hours and up to several days, the catheter position and lysis progress were also monitored by CT angiography.
After completion of the lysis, the internal cerebral venous system was recanalised, the thalamic oedema had completely resolved and the patient was neurologically normal after rehabilitation.
Interventional angiography - vascular occlusion measures
Interventional neuroradiology has established itself as a highly specialised field for the endovascular treatment of vascular diseases of the central nervous system. In this context, vascular-opening measures have been developed, for example to restore blood flow in acute strokes, or vascular-closing measures, for example to treat aneurysms in acute subarachnoid haemorrhage.
In many diseases of the vascular system that can lead to bleeding (e.g. subarachnoid haemorrhage in aneurysms of the basal cerebral arteries) or in fistula connections between arteries and veins, vascular occlusion measures can be performed as neurointerventions.
Endovascular treatment can be considered, for example, for
- Aneurysms of the basal cerebral arteries
- Arteriovenous fistulas
Case studies for vascular occlusion measures
Endovascular aneurysm coiling for incisional aneurysms
Example of an endovascular closure(coiling) of an aneurysm of the anterior cerebral artery.
Acute SAH with ophthalmoplegic aneurysm
Patient with annihilation headache and acute oculomotor dysfunction. The cause was a ruptured aneurysm(subarachnoid haemorrhage (SAB) on CT) of the internal carotid artery. In the follow-up 3 months after coiling complete occlusion.
Direct fistula between the carotid artery and cavernous sinus after traumatic brain injury with skull base fracture. Pre-interventional right internal carotid artery selectively visualised in p.a. projection. Immediately after injection of contrast medium, contrast medium passes into the cavernous sinus and arterialised draining veins.
Control after coiling of the fistula. Same image as pre-interventional, selective injection of the right internal carotid artery in p.a. projection. Now almost completely closed fistula. No more filling of the cavernous sinus. No steal effects. Now regular filling of the intracranial arteries.
Indirect fistula between the carotid artery and the cavernous sinus
Indirect fistulas between branches of the carotid artery and the cavernous sinus occur, as in this case, after cavernous sinus thrombosis in the context of sinus infections. When the thrombosis recedes, short-circuiting occurs between arteries in the wall of the sinus and the venous blood flow in the sinus. This results in countless tiny fistula connections.
Contrast of the internal or external carotid artery leads to direct transfer of contrast medium with early filling of the cavernous sinus and the ophthalmic vein.
Due to the increase in pressure, the function of the sinus as a draining vein is lost. However, the resulting venous congestion in the eye socket is particularly problematic and can lead to visual impairment.
Selective visualisation of the internal and external carotid artery. The clearly premature filling of the cavernous sinus with outflow via the dilated ophthalmic vein can be seen.
A possible venous access to the cavernous sinus is via the retrograde ophthalmic vein. The image shows the cavernous sinus already largely filled with coils, the microcatheter from the left and another coil in the microcatheter.
After transvenous embolisation, the fistula is completely closed.
