Neurological Research A Journal of Progress in Neurosurgery, Neurology and Neurosciences ISSN: 0161-6412 (Print) 1743-1328 (Online) Journal homepage: https://www.tandfonline.com/loi/yner20 Long term EEG analytical and neurological followup study in completed stroke patients after extraintracranial vascular anastomosis H. Wassmann, K.H. Holbach & D.K. Böker To cite this article: H. Wassmann, K.H. Holbach & D.K. Böker (1984) Long term EEG analytical and neurological follow-up study in completed stroke patients after extra-intracranial vascular anastomosis, Neurological Research, 6:3, 115-117, DOI: 10.1080/01616412.1984.11739674 To link to this article: https://doi.org/10.1080/01616412.1984.11739674 Published online: 20 Jul 2016. Submit your article to this journal Citing articles: 2 View citing articles Full Terms & Conditions of access and use can be found at https://www.tandfonline.com/action/journalInformation?journalCode=yner20 Communication Long term EEG analytical and neurological follow-up study in completed stroke patients after extra-intracranial vascular anastomosis H. Wassmann, K.H. Holbach*, and D.K. Boker Neurochirurgische Universitatsklinik, 0 5300 Bonn-Ve nusberg, West Germany • Neurochirurgische Abt., Katharinen-Hospital, 0 7000 Stuttgart, West G ermany In 33 chronic stroke patients, who had int ernal carotid or middle cerebral artery occlusion that resulted in neurologica l deficit persisting for an average of more than 70 vyeeks, it was possible to perform a postoperative ·follow-up study for a period of six to eight years aft er extraintra cranial vascular anastomosis. Serial neurological examinations with grading of motor d eficit and EEG analyses w ere performed to assess t he clinical course of the ce rebral lesion. These long term examinations showed a postop erative co ntinuing improvem ent of electrica l brain activity in nearly two thirds of the patients, nine patients showed no significant changes and three worsened. The EEG analytical findings correlated well to the neurological findings. An increase of electrical brain activity was bilateral with accentuation over the affected hemisphere, a phenomenon known from follow-up nrCBF measurements after anastomosis. During the follow-up one patient died five yea rs, one six years fo llowing stroke under signs of cardiovascular dis ease, and one after six years suffering from a recurrent stroke opposite to th e side of anastomosis. In conclusion th e findings indicate that EEG analysis is of value for assessment of long term follow-up of cerebral ischaemic lesions, chronic ischaemic alterations of the brain ca n be improved by anastomosis, and especially in co mparison to a non-operated group of stroke patients, th e course of th e operated one seemed to be m o re advantageous, as the five-yea r survival rate of th e Framingham study for strok e victims is 69%. Keywords: EC/I C bypass, EEG analysis, hyperbaric oxygen therapy INTRODUCTION In our clinic, extra-intracranial arterial bypass (EIAB) operation has been carried out since 1974 in certain patients with occlusive cerebrovascular disease. To assess the lon g term effe ctiven ess of this operation, all th ese patients have been su bjected to n eurolo gical investigatio ns at six m o nth s to one year intervals. Thirty-three patients had this operation in the chronic poststroke stage and their follow-up for 6 to 8 years with regard to neurological function and significance of EEG studies is the subject of this study. MATERIAL AND METHODS The following case hist o ry illu strates our m ethod of stud yin g these patients: A 55 year old female suffe red a stroke in May 1977 with left hemiplegia due to right internal carotid artery occlusion. Within two weeks the hemipl egia improved from ze ro to eight points (eighteen points re present the normal motor power of one side) ( Figure 7) . On admis sion to our clini c one month later sh e was in a chronic poststroke stage w ith moderately severe left h em iparesis (n eurological score: eight points). She was given hype rbaric oxygen "' 1984 Butterwort h & Co (Publishers) Ltd 01 60- 641 2/8 4/ 060 1 1 5- 03$03 00 therapy (HOT) which res ulted in improvem ent of th e left hemipares is by another three points 1 . This was considered to be evidence for the partial reve rsi bi lity of the neurological defi cit and was the indi cation for bypass operation, whi ch was carried out in Jul y 1977. Postoperative angiography showed a functioning bypass with filling of the territo ry of th e left mid dl e cerebral artery. In th e course of th e next six month s there was further improvement of th e left hemipares is by three points and at the end of the second year by another point. The res idual h em ipare sis in vo lves distal mu scles and remain s un altered up to the present. The patient however fee ls well and is able to carry o ut full ho u se hold activiti es. Comp uter analysis EEG shows a signifi cant increase of Alpha-activity on th e af fected sid e during th e first year after surgery. There is also slight increase of Bet aactivity wi th decrease of Th eta-activit y. With th e exception of a transient in crease in th e postoperative period, the Delta-activity shows no essenti al chan ges. Durin g th e observation p eriod, the o ri ginal EEG (Figu re 2) shows a reduction of t h e fo cus in the ri ght t e mpo ropari etal region with acce ntuatio n of Alpha waves. Neu ro logica l Research, 1984, Vo lum e 6, Sep te m ber 1 ·1 s EEG after stroke: H. Wassman et a/. EEG- AR EPE 80 Neuro I. Score 60 18 -c8 40 c::·:::.·::::.·:::::~:::0······=-~:::::.:::::..::::;..::::..::::;::::.::::.·····• p 16 •.............•.............. + ........ :::::.::::······· 20 14 6 ~ 0-----< 12 CR 10 ------------ -----------------.....----------.·..,__ ; 8 . .............................. ,,.,"' __., ./"' a ,/---- ', '............ ______ -------6 ..:=.::-.::...:. :_:················· ::··;;.··-~.::- ............... .....-...................... ······ ...............··························• 0 ...._ 4 -e>-- - II - o - - - -().... - -...a- --a- - -c-- _ -c 8 o6 2 5 177 6 177 Stroke pre 7 1 77 A 0,1 0,5 HOT post! OP post EIAB 1 • 2 3 5 4 6 reus · Pat. 312 Figure 1. Neurological (star) and EEG analytical follow-up examinations of a patient with right internal carotid artery occlusion undergoing hype rbari c oxygen therapy (HOT) and extra-intracranica l arterial bypass (EIAB) operation. Electrical power equival ent (EP E) values o f the affected (AR) and contralate ral region ( CR) are divided in the Beta-, Alpha-, Theta- and Delta-wave-range. Neurologica l score represents the sum of motor power (6 points represent normal motor power) of hand, arm and leg. A total of thirty three patients in chronic poststroke stage were treated by EIAB operation. Twenty-s ix were men and seven women with a median age of 50.3 years. The cause of vascular insufficiency was carotid occlusion in 28 cases and middle ce rebral artery occlusion in 5 cases. The indication for bypass operation was improvement under hyperbaric oxygen therapy in all cases. Group Ill (Figure 5) with 21 patients showed significant improvement of neurological function by 5 points during the first postop erative year. This corre lates with an increase of Alpha-activity by 15 points. This improvem ent was m aintained over the 8 year observation period. One patient died in the sixth postoperative year due to myocardial infarction and a second patient died as a result of stroke involvin g the side opposite to that of surgery. RESULTS All these patients showed a patent bypass in th e postoperative period as determined by Doppl er sonography and angiography. As a result of observation of these patients over a period of six to eight years and based on clinical neurological assessment and EEG analysis we have divided the patients into three groups: Group I with three patients showed essentially no change in th e first year after surgery. From the second postop erative year there was aggravation of neurological deficit by two points and slight decrease of Alpha-activity. One patient died five years after operation as a result of myocardial infarction (Figure 3) ; Group II (Figure 4) with nin e patients showed no essential change over an eight year period apart from a slight postope rative in crease of Thet a- and Deltaactivities. 11 6 Neurologica l Research, 1984, Volu m e 6, September DISCUSSION AND CONCLUSION The long t erm observation after bypass operatio n of thirty-three selected patients in chronic poststroke stage with fixed moderate neurological deficit showed that in two thirds of these patients there was a definite improvement of clinical neurological statu's and EEG findings within the first postoperative year and that this improveme nt was maintained. In one third th ere was eith e r no improvem ent or sli ght deterioration after the second postoperative year. In conclusion it can be stated that EEG is a reliable and useful method for follow-up of patients after bypass operation for the chronic poststroke stage and that it correlates well with clinical neurological findings 2 . In addition the clinical co urse of properly se lected patients after bypass operation is better than that of si milar pati ents treated conservatively, accord in g to Framingham study, the 5 years survival rate of sixty-nine percent in stroke EEC after stroke: H. Wassman et a/. H. A. 312 AR •-· ··---/·-~· ~ ·--\.-,··.- ./ J-~ - - v ~v-~---~~- -- - . . (pfi Mu,.l. ~ · -. Sc;ttt pre OP 6-'77 .,. -------·------·----- ·---------------- 30 ·············•············· p .......................... so,.v[':..___ 8 _.,_--"- ,.. 6 AR ,'.;~;V\ft~/r/ll'.f'vv.M;~J{\rWI,J-v-11/'--.. B- '78 0 -- --,·- ~---,=-,-,,.-.,,-, --pi' f-2-,_..,: EIAB post - -c--c--c--=- --- _, ::.=...r-=--....-..:....,-c----r-T---.--'....:.....,--'-.,-,'"" -oi= --o- -_.., _ _ Figure 4. Neurological (star) and EEG analytical follow-up mean values of 9 patients (group · II) undergoing extra-intracranial arterial bypass (EIAB) operation. h - 2HI.Uhl 10 Hfj 60 11 '80 so ......•. ------··· __________... ----·· 30 20 _, AR t/ft· __ , __, _____ __ -- ______ , __ pu o, 'i '83 - put or c , -- a- - c - - "-_a-- a-- 0.5 a'"" Figure 5. Neurological (star) and EEG analytical follow-up mean values of 21 patients (group Ill) undergoing extra-intracranial arterial bypass (EIAB) operation. Figure 2. Follow-up original EEG of the affected (AR) and contralateral region (CR) of the pati e nt with right internal carotid artery occlusion undergoing extra-intracranial arterial bypass (EIAB) operation. ~ · 3 (II I Pol :::::',1'0 3 so 2 ~·o~-9---~-~--~--4---~ 1 30 ~"' + 20 , _, __ ,_ ~ -- - ---· Figure 3. Neurological (star) and EEG analytical follo w- up m ean values of three patients (group I) undergoing extra-intracranial arterial bypass (EIAB) operation. patients as a natural course is very unfavourable 3 . Most authors agree, that spontaneous recovery of neurological deficit is rarely observed in the chronic poststroke stage beyond the third month 4 •5 . REFERENCES 1. Wassmann, H. Quantitativ e Indikatoren des hirnelektri sc hen Wirkungsverlaufes bei hyperbarer Oxygenierun g. Z. EEC-EMC 1980,11,97-101. 2. Hoi bach, K.H., H. Wass mann and Sanchez, F. EEG analysis for evaluating chronic cerebral ischaemia treate d by hyperbari c oxygenation and microsurgery. }. Neural. 1978, 219, 227-240. 3. Sacco, R.L , Wolf, P.A., Kannel, W.B., and McNamara, P.M. Survival and Recurrence following strok e. Th e Framingh am study. Stroke, 1982, 13, 290-295 . 4. Newman, M. The proc ess of recovery after h emiplegia. Stroke 1972, 3, 702-710. 5. Skilbeck, C.E., Wade, D.T., Hewer, -R.L. and Wood, V.A. Recovery after stroke.}. Neural. Neurosurg. Psychiatry. 198 3, 46, 5-8 . Ne urolog i ca l Research, 1984, Volume 6, September 1 ·17