BRAIN DEATH - The contribution of cerebral angiography. A 5-years experience.

Transcription

1 BRAIN DEATH - The contribution of cerebral angiography. A 5-years experience. Poster No.: C-1170 Congress: ECR 2011 Type: Educational Exhibit Authors: I. Georgiou 1, V. KARTSOUNI 2, G. STAINHAUER 3, N. Keywords: DOI: GALIATSATOS 2 ; 1 ATHENS/GR, 2 ATHENS/GR, 3 athens/gr Catheter arteriography, Neuroradiology brain, Interventional vascular /ecr2011/C-1170 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 15

2 Learning objectives Our objective is to highlight the usefulness of the 4 vessel cerebral angiography in the diagnosis of brain death, especially in cases of patients where diagnosis is in question and presenting cases where the angiography results are opposed to the clinical neurological examination findings. Background Brain death is defined as the complete and irreversible loss of function of the brainstem. The key clinical criteria for the diagnosis of brain death include the presence of coma and apnea and the absence of brainstem reflexes. Although the clinical neurological assessment remains the most basic method for diagnosing brain death, the application of confirmatory tests especially the 4 cerebral vascular angiography, is particularly useful in cases of potential organ transplantation, where the confirmation of brain death is difficult due to the occurrence of clinical signs that indicate some retention of brain function or when coexisting conditions such as Guillain-Barret syndrome, severe hypothermia and the use of drugs that cause confusion and lead to misdiagnosis. Imaging findings OR Procedure details In the last 5 years, 32 (thirtytwo) patients in a comatose state (22 males and 10 women with mean age of 50 years) have been transferred to the angiography room from the ICU for confirmation of brain death. 24 of those patients were due to primary brain damage (16 injuries, 2 tumors, 4 hemorrhages, 2 sagittal sinus thrombosis) while the remaining 8 were due to secondary brain damage (cerebral hypoxia due to cardiorespiratory insufficiency). A detailed clinical neurological assessment of all patients was acquired and a selective 4-vessel cerebral digital subtraction angiography was performed with the use of high pressure contrast media injection. In 25 patients (79%) brain death was confirmed by showing complete absence of cerebral blood flow, while in 7 patients, despite the suspicion of the clinical neurological examination, confirmation of brain death was not possible due to delayed filling of the carotid arteries above petrosal sinus level and lack of vertebrobasilar plexus contrast enhancement. The clinical criteria for diagnosis of brain death include coma, absence of brainstem reflexes and apnea. Confirmation of brain death is difficult when manifested clinical signs suggest some remaining brain function coexisting with conditions such as Guillain-Barret Page 2 of 15

3 syndrome, locked-in syndrome, severe hypothermia or drug use that causes confusion and leads to misdiagnosis. In these cases confirmatory methods are useful. Digital subtraction angiography, the Doppler ultrasound and scintigram scan reveal the state of blood flow to the brain, while the EEG records the electrical activity of the brain. The findings of angiography in case of brain death are: 1. Absence of cerebral vessel outlines of the carotid and vertebral arteries at level of entry in the skull 2. The external carotid artery network can be patent 3. There may be delayed filling of the upper sagittal sinus While performing angiography the contrast agent is injected at high pressure. The brain vessel network may not be enhanced due to: 1. Systolic blood pressure is not high enough to propagate blood to the brain vasculature. 2. Neuroglia perivascular edema and the formation of the subendothelial bullae caused by ischemia, leads to abnormal vascular wall collapse of smaller diameter vessels which in turn lead to increase endovascular resistances. Images for this section: Page 3 of 15

4 Fig. 1: Selective catheterization of the right carotid artery Page 4 of 15

5 Fig. 2: Retrograde filling of the left internal carotid artery through the anterior anastomosing and right external carotid arteries. Page 5 of 15

6 Fig. 3: Right common carotid artery. Only the external carotid network is displayed. Page 6 of 15

7 Fig. 4: The flow of the left vertebral artery was interrupted at the foramen magnum. Page 7 of 15

8 Page 8 of 15

9 Fig. 5: The flow of the right internal carotid interrupted at the level of initial cervical spine. Fig. 6: The outline of the right common carotid artery shows only the network of the external carotid. Page 9 of 15

10 Fig. 7: Interruption of flow in the left vertebral artery before entering the skull. Page 10 of 15

11 Fig. 8: Normal network distal to the anastomotic segment of the right common carotid artery. The blood flow is slow. Page 11 of 15

12 Fig. 9: Normal network distal to the anastomotic segment of the right common carotid artery. The blood flow is slow. Page 12 of 15

13 Fig. 10: Interruption of blood flow in the left vertebral artery at the foramen magnum. Page 13 of 15

14 Conclusion The clinical neurological assessment remains the most basic method for the diagnosis of brain death. The main indication for 4-vessel angiography is the early diagnosis of brain death in order to speed up the patients for organ transplants as well as to confirm brain death in subjects where clinical confirmation is hampered by the presence of other factors such as hypothermia or taking drugs. Complete interruption of blood flow to the brain for more than 10 minutes in adults with normal temperature, is incompatible with survival of brain tissue. Therefore, the complete absence of cerebral circulation outline and the complete absence of blood flow to the brain diagnostic for brain death. Personal Information Radiology Department, "St. Savvas" Oncologic Hospital, Athens, Greece References 1. Selective 4 vessels angiography in brain death: a retrospective study.savard M, Turgeon AF, Gariépy JL, Trottier F, Langevin S. Can J Neurol Sci Jul;37(4): Brain blood flow in the neurological determination of death: Canadian expert report.shemie SD, Lee D, Sharpe M, Tampieri D, Young B; Canadian Critical Care Society. Can J Neurol Sci.2008 May;35(2): Accuracy of clinical evaluation in the determination of brain death.flowers WM Jr, Patel BR. South Med J Feb;93(2): Digital subtraction angiography (DSA) in the evaluation of brain death. A comparison of conventional cerebral angiography with intravenous and intraarterial DSA.Vatne K, Nakstad P, Lundar T. Neuroradiology. 1985;27(2): Analysis of angiographical findings in patients with severe brain disorders progressing to brain death. Kouji H et al. No To Shinkei Jul;41(7): Persistence of isolated flow in the internal carotid artery in brain death. de Freitas GR, André C, Bezerra M, Nunes RG, Vincent M. J Neurol Sci Jun 15;210(1-2):31-4. Page 14 of 15

15 7. Persistence of cerebral blood flow after brain death.flowers WM Jr, Patel BR. South Med J Apr;93(4): Review. 8. Reliability in diagnosis of brain death. Paolin A, Manuali A, Di Paola F, Boccaletto F, Caputo P, Zanata R, Bardin GP, Simini G. Intensive Care Med Aug;21(8): Page 15 of 15