BACKGROUND: Arteriovenous malformations (AVM) markedly alter the distribution 
of the regional cerebral blood flow, as they consist of abnormal arteries and 
veins with no resistance vessels between them. The aim of this study was to the 
evaluate diagnostic utility of cerebral perfusion scintigraphy (dynamic phase 
and SPECT) in patients with AVM. 
MATERIAL AND METHODS: Nineteen patients were examined. All the patients 
had been previously diagnosed with AVM and qualified for intravascular embolization. 
Brain scintigraphy was performed with 99mTc-ECD and included dynamic phase and 
SPECT imaging. The regional blood flow was evaluated visually and semi quantitatively, 
based on comparison between the activity in the two symmetrical regions of interest. 
Differences higher than 10% were considered significant. Cerebral angiography 
combined with intravascular embolization was carried out after a scitigraphic 
examination. 
RESULTS: Based on angiograms, the diameter of the AVM nidus was estimated 
and varied from 1.0 cm to 9.0 cm. In 13 cases, AVM were visible in the dynamic 
scintigraphy as areas of increased tracer activity. In each case, SPECT images 
showed the AVM nidus as a region of decreased tracer accumulation. Hypoperfusion 
in the brain tissue adjacent to the nidus was seen in 15 subjects. In one patient 
cerebellar diaschisis was present. The average ratio of activity in the region 
of AVM to activity in the normally perfused tissue calculated by semiquantitative 
analysis was 77.5 &plusmn; 10.9%. 
CONCLUSION: Cerebral perfusion scintigraphy (SPECT images and dynamic scintigraphy) 
allows one to identify perfusion disturbances caused by the presence of intracranial 
AVM

Gil, Krzysztof

Nocuń, Anna

Szajner, Maciej

Zaorska-Rajca, Janina

English

Via Medica Journals

43Nuclear Medicine Review 2004 Vol. 7, No. 1, pp. 43–48Copyright © 2004 Via MedicaISSN 1506–9680www.nmr.viamedica.plShortcommuni-cationsDiagnostic value of cerebral perfusionscintigraphy in evaluation of intracranialarteriovenous malformations— preliminary reportAnna Nocuń1, Maciej Szajner2, Krzysztof Gil3,Janina Zaorska-Rajca11Chair and Department of Nuclear Medicine, Skubiszewski MedicalUniversity of Lublin, Poland2Chair and Department of Interventional Radiology and Neuroradiology,Skubiszewski Medical University of Lublin, Poland3Chair and Clinic of Neurosurgery and Paediatric NeurosurgerySkubiszewski Medical University of Lublin, Poland[Received 2 IV 2004; Accepted 13 IV 2004]AbstractBACKGROUND: Arteriovenous malformations (AVM) markedlyalter the distribution of the regional cerebral blood flow, as theyconsist of abnormal arteries and veins with no resistance ves-sels between them. The aim of this study was to the evaluatediagnostic utility of cerebral perfusion scintigraphy (dynamicphase and SPECT) in patients with AVM.MATERIAL AND METHODS: Nineteen patients were examined.All the patients had been previously diagnosed with AVM andqualified for intravascular embolization. Brain scintigraphy wasperformed with 99mTc-ECD and included dynamic phase andSPECT imaging. The regional blood flow was evaluated visual-ly and semi quantitatively, based on comparison between theactivity in the two symmetrical regions of interest. Differenceshigher than 10% were considered significant. Cerebral angiog-raphy combined with intravascular embolization was carried outafter a scitigraphic examination.Correspondence to: Anna NocuńDepartment of Nuclear MedicineSkubiszewski Medical University of Lublin, SPSK 4ul. Jaczewskiego 8, 20–954 Lublin, PolandTel/fax: (+48 81) 72 44 389, e-mail: anna@nocun.comRESULTS: Based on angiograms, the diameter of the AVM ni-dus was estimated and varied from 1.0 cm to 9.0 cm. In 13 cas-es, AVM were visible in the dynamic scintigraphy as areas ofincreased tracer activity. In each case, SPECT images showedthe AVM nidus as a region of decreased tracer accumulation.Hypoperfusion in the brain tissue adjacent to the nidus wasseen in 15 subjects. In one patient cerebellar diaschisis waspresent. The average ratio of activity in the region of AVM toactivity in the normally perfused tissue calculated by semiquan-titative analysis was 77.5 ± 10.9%.CONCLUSION: Cerebral perfusion scintigraphy (SPECT imag-es and dynamic scintigraphy) allows one to identify perfusiondisturbances caused by the presence of intracranial AVM.Key words: cerebral arteriovenous malformations, cerebralperfusion scintigraphy, SPECT, angiographyIntroductionArteriovenous malformations, colloquially referred to as angi-omata, constitute 4% of intracranial tumours and are innate mal-formations of brain blood vessels in terms of their structure andfunction. They can be characterised by the presence of patholog-ical arteriovenous connections with a high blood flow. These con-nections can be present in the form of direct fistulae between anartery and a vein, or a knot of distended and entangled bloodvessels — the so-called nidus. It is possible to distinguish betweenseveral kinds of angiomata on the basis of their size, the type ofvessel as well as their microscopic image. The aforementionedkinds include arteriovenous, arterial, venous, capillary, cavernousand other angiomata. From the clinical point of view, AVM mani-fests itself as an intracranial tumour (epileptic seizures, deficiencysigns, increased intracranial pressure) or the first symptom of AVMcan be intracranial (subarachnoid) haemorrhage. The medicaltreatment of AVM consists in removal or closure of the nidus bymeans of a surgical operation, embolization, or stereotactic ra-diotherapy with gamma rays. Very little relevant literature concern-44Nuclear Medicine Review 2004, Vol. 7, No. 1www.nmr.viamedica.plShortcommuni-cationsing the role of SPECT in the evaluation of the treatment results ofbrain arteriovenous malformations through intravascular embo-lization encouraged us to analyse the problem.The aim of this study was to demonstrate scintigraphic evalu-ation of cerebral perfusion in patients with intracranial haemangi-omas. Our report has a preliminary character and is planned tobe a part of more comprehensive research, which will include fur-ther important aspects of this issue.Material and methodsNineteen patients (9 women and 10 men) from the age of 12––67 years (the average age was 28.6 years) were studied. All thepatients had been previously diagnosed with intracranial AVM andsubsequently qualified for the intravascular embolization proce-dure. All the patients were in good clinical condition and had nosymptoms of recent intracranial haemorrhage. In 10 patients thehaemorrhage had been present in the past. For 16 patients it wasto be the next embolization, 3 patients were also treated with gam-ma rays. In addition to this, 8 persons were treated becauseof epilepsy which was caused by the presence of AVM. In 2 casesangioma was located in cerebellum hemisphere, in the remainingcases it was situated supratentorially.Brain scintigraphy was performed after the intravenous ad-ministration of 99mTc-ECD (ethylcysteinate dimer) in doses from491 to 925 MBq. The examinations were carried through with two-head gamma-camera VARICAM (GE Medical Systems), connect-ed with dedicated computer system XpertPro. The activity abovethe head and neck was recorded  immediately after the adminis-tration of the radioisotope and the acquisition was performed overa period of 1.5 minutes with the resolution of 2 seconds in anteri-or-posterior and posterior-anterior projections. Brain SPECT wascarried out 20 minutes after radiotracer administration. Acquisi-tion was performed, using high-resolution collimator, 128 × 128matrix, with one projection for each 3° in a 360° orbit for a total of120 projections. The images were reconstructed with Metz filterand attenuation coefficient of 0.11.SPECT images were analysed visually and based on semi-quantitative method with the help of the Compart program (Com-part, Warsaw, Poland), which defined regions of interest in trans-verse intersections at the cerebellar level and supratentorially, di-viding the cerebral cortex of each hemisphere into 6 sectors. Theactivity in a given sector was compared with the opposite side,and differences higher than 10% were considered as significant[1]. In the case of one patient with angioma located in the medialline of the body, regions were defined manually and the activitywithin the pathological change was compared with the region ofnormal brain tissue in its direct proximity. Radionuclide study wasperformed prior to angiography, which was followed by intravas-cular embolization.Angiography was carried out under general anaesthesia withan injection into right femoral artery. A diagnostic catheter wasintroduced successively into each of the main brain arteries,a contrast medium was administered and angiographic imageswere obtained, using Siemens equipment (Multistar).ResultsSPECT results are contained in Table 1 and angiographic re-sults in Table 2. Figures 1–4 illustrate scintigraphic and angio-graphic changes in selected cases. The example of semiquanti-tative method is depicted by Figure 5.In all cases, angiography showed the presence of brain angi-oma. Based on this examination the largest diameter of the angi-oma nidus was determined in each case. These varied from1.0 cm to 9.0 cm (the average was 3.2 cm).In the dynamic scintigraphy (DF, dynamic phase), AVM werevisible in the first seconds of the acquisition, as the regions ofTable 1. Results of scintigraphic imaging in patients with AVMNo. Initials Age [years] Localization of AVM Coefficient AVM/N Number of sectors Visualization in DF1 TW 12 Left parieto-frontal region 52% 2 +2 PP 17 Left cerebellar hemisphere 71% 1 +3 KR 20 Central structures 73% 2 +4 GK 50 Right temporal region 86% 2 –5 DR 15 Right frontal region 87% 1 –6 MA 24 Left fronto-temporal 60% 6 +7 RK 52 Bilateral parietal region 89% 1 –8 JW 16 Right thalamus 77% 3 +9 DJ 18 Right parieto-occipital  region 87% 2 +10 TP 24 Right occipital region 89% 2 +11 MS 26 Right parietal region 74% 1 +12 HG 67 Right parietal region 70% 4 –13 MK 13 Left fronto-temporal region 80% 1 +14 KE 16 Left fronto-temporal region 69% 2 +15 HZ 48 Left cerebellar hemisphere 85% 1 +16 IR 25 Right parietal region 81% 1 –17 PK 23 Right parietal region 66% 1 +18 KL 49 Left temporal region 88% 1 –19 GW 29 Right thalamus 89% 1 +AVM/N — the ratio of activity in the AVM region to activity in normally perfused tissue; DF — dynamic phase45www.nmr.viamedica.plAnna Nocuń et al., Cerebral perfusion scintigraphy in evaluation of intracranial arteriovenous malformationsShortcommuni-cationsincreased accumulation of the isotope in 13 patients (68%), in-cluding the patients in whom the diameter of the nidus was small-er than 3 cm in 5 cases (50%) and in all cases of AVM larger thanor equal with 3 cm. In each patient, SPECT examination showedthe nidus of angioma as a region of decreased accumulation ofthe radiotracer.In 15 subjects (78%) (cases 1–4, 6, 8, 11–19) hypoperfusionof the adjacent region was observed, including all patients witha pathological change larger than 3 cm in diameter. In one case(in a patient no. 6) with a change whose diameter was 9 cma decreased perfusion in cerebellar hemisphere opposite the ce-rebral hemisphere with AVM was observed.As far as semiquantitative evaluation is concerned, the activi-ty in the changed region, expressed, as percentage ratio to theopposite side (AVM/N coefficient), varied from 52% to 89% (theaverage of 77.5% ±10.9%). In the case of the patient with a diag-Table 2. Angiographic findings in patients with AVMNo. Initials Age [years] The largest diameter of a nidus [cm] Feeders of AVM1 TW 12 1.5 LMCA2 PP 17 3.5 LIPCA, LSCA3 KR 20 6.0 BMCA, BAChA, BACA, BPCA4 GK 50 1.5 RPCA5 DR 15 2.0 RACA6 MA 24 9.0 BACA, LMCA7 RK 52 3.0 BACA8 JW 16 2.0 RMCA9 DJ 18 3.0 RMCA10 TP 24 2.0 RPCA11 MS 26 5.0 RMCA12 HG 67 1.0 RMCA13 MK 13 4.5 RMCA14 KE 16 2.0 LMCA15 HZ 48 2.0 LIPCA16 IR 25 1.0 RMCA17 PK 23 4.5 RMCA18 KL 49 1.5 LPCA19 GW 29 6.0 RMCA, BPCAACA — anterior cerebral artery; SCA — superior cerebellar artery; MCA — middle cerebral artery; AChA — anterior choroidal artery; PCA — posterior cerebral artery; R — right;L — left; B — bilateral; IPCA — inferior posterior cerebellar arteryFigure 1. Scintigraphy in case 17. A. Dynamic phase in A-P projection, showing a site of increased activity in the right cerebral hemisphere (arrow);B. SPECT, showing hypoperfusion in the right fronto-parietal region.AB46Nuclear Medicine Review 2004, Vol. 7, No. 1www.nmr.viamedica.plShortcommuni-cationsFigure 2.  Right internal carotid angiograms in case 17, showing an AVM fed by the middle cerebral arterial branches. A. A-P projection; B. Lateral projection.A Bnosed cerebellar diaschisis, the blood flow in the cerebellar hemi-sphere contralateral to angioma was 87% of the blood flow in theother cerebellar hemisphere.DiscussionArteriovenous angiomata are characteristic for the decreasedresistance of blood flow which in consequence results in stealingblood from the healthy parts of the brain, where blood flow resis-tance in capillary vessels is higher. The regions of decreased per-fusion may be present in the closest proximity of angioma or ina remote region in the same or opposite hemisphere [2]. Asa consequence of surgical treatment or embolization, in the re-gion with disturbed autoregulation, normalisation of the blood flowor various degrees of hyperemia may be observed [2–5]. The vi-sualization of blood flow redistribution proves to be very signifi-Figure 3. Scintigraphy in case 15. A. A region of increased activity (arrow) in the left  cerebellar hemisphere is seen in dynamic phase (projection P-A);B. Hypoperfusion in the left cerebellar hemisphere in SPECT.AB47www.nmr.viamedica.plAnna Nocuń et al., Cerebral perfusion scintigraphy in evaluation of intracranial arteriovenous malformationsShortcommuni-cationsphy is a non-invasive method which allows safe diagnosis of thedisturbances of brain blood flow. The usefulness of this methodfor the imaging of ischaemia and hyperaemia in AVM was de-scribed in a number of papers [2–6]. The necessity to confirm infollow-up study the remission of hyperaemia, diagnosed by SPECTperformed after embolization and before the next phase of embo-lization or surgical operation, is particularly emphasised, as it al-lows to avoid disastrous complications. SPECT constitutes a com-plementary method to angiography. Angiography enables deci-sion-making as to the choice of treatment and which highlights allelements of angioma: blood-supplying arteries, the nidus of angi-oma and the veins carrying blood from it. In this examination, thestealing phenomenon is characterised by a worse filling of con-trasting agent in other arteries in the region of the same bloodvessel system where angioma is present. In angiography of thearteries opposite to angioma, this “stealing” may cause the bloodvessels close to AVM or angioma itself to be filled with blood bycommunicating arteries.In the group examined by us, all AVM were recognisable asregions of decreased accumulation of radiotracer. No disturbancesin the blood flow in the opposite cerebral hemisphere were ob-served. In the case of one patient, there was ischaemia of thecerebellar hemisphere located opposite to angioma (diaschisiscerebellaris). This symptom is defined as a reduction in the me-tabolism and blood flow in the cerebellar hemisphere contralater-al to a supratentorial cerebral lesion, such as a malignant tumour,infarction, intracranial haematoma, or angioma [7, 8]. Brain inju-ries of different causes can impair neuronal impulses and inter-rupt connections (corticopontocerebellar pathway is said to becommonly involved) with other cerebral regions, which may bedistant from the original lesion. Cerebral regions receiving poorafferent signals become hypo-functioning, decrease their metab-Figure 5. Regions of interest in case 12, dividing the cerebral cortex ofeach hemisphere into 6 sectors. Perfusion in the right sectors 3–6 is sig-nificantly decreased, compared with the left hemisphere. AVM/N — theratio of activity in the AVM region to activity in normally perfused tissue.Figure 4. Left vertebral angiograms in case 15, showing an AVM fed by the branches of the inferior posterior cerebellar artery. A. A-P projection;B. Lateral projection.cant in the post-surgical treatment of a patient and in the planningof the next stage of angioma treatment, especially because ofadverse consequences of hyperperfusion in the form of cerebraloedema and intracranial haemorrhage. Perfusion brain scintigra-R 1 2 3 4 5 6AVM/N 0.97 1.00 0.89 0.73 0.70 0.8248Nuclear Medicine Review 2004, Vol. 7, No. 1www.nmr.viamedica.plShortcommuni-cationsolism and appear as low-uptake areas in SPECT images [8]. Themost commonly seen pattern of this phenomenon-crossed cere-bellar diaschisis , was present in only one examined patient withthe largest of all lesions.In 15 cases hypoperfusion of the region adjacent to the nestwas observed. Since no CT or MRI studies were carried out, it isnot possible to ascertain whether the region of hypoperfusionobserved in SPECT in the vicinity of angioma nidus was a result ofstructural or functional changes. Disturbances of perfusion deter-mined by SPECT greater than structural changes in CT and MRIare described in papers, where the above-mentioned techniqueswere used simultaneously [2, 5, 9]. This proves SPECT to be use-ful in the planning of treatment, predicting complications and con-trolling therapy in the case of surgery and embolization as well asradiosurgical procedures. There are reports which have confirmedthe high sensitivity of angioscintigraphy in the evaluation of theremission of changes after the use of the aforementioned treat-ment method [10].ConclusionsThe above-mentioned report is of preliminary character.However, it allows one to draw the following conclusions:1. 99mTc-ECD SPECT imaging can be used to assess the perfu-sion disturbances (on the level of capillary blood vessels) inthe area adjacent to the AVM nidus and also in the case ofremotely located brain structures.2. The dynamic phase of scintigraphic examination providesadditional information on the dynamics of blood flow throughthe nidus of AVM, especially in the case of large lesions.References1. Tash K, Asenbaum S, Bartenstein P et al. European Association of Nucle-ar Medicine procedure guideline for brain perfusion SPECT using99m-Tc labelled radiopharmaceuticals. Eur J Nucl Med. 2002; 29:36–42.2. Takeuchi S, Abe H, Nishimaki K et al. Cerebral haemodynamic changesafter endovascular treatment of arteriovenous malformations. ActaNeurochirurgica 1994; 127: 142–150.3. Ogasawara K, Yoshida K, Otawara Y et al. Cerebral blood flow imag-ing in arteriovenous malformations complicated by normal perfusionpressure breakthrough. Surg Neurol 2001; 56: 380–384.4. Kuroda S, Ushikoshi S, Moukin K et al. Postoperative hyperperfusionin dural arteriovenous fistula associated with venous ischaemia: casereport. Surg Neurol 1998; 49: 406–411.5. Takeshita G, Toyama H, Nakane K et al. Evaluation of cerebral bloodflow changes on perifocal brain tissue SPECT before and after re-moval of arteriovenous malformations. Nucl Med Communs 1994;15: 461–468.6. Bloom M, Jacobs S, Pile-Spellmann J et al. Cerebral SPECT imaging:effect on clinical managment. J Nucl Med 1996; 37: 1070–1073.7. Leo G, Flores I, Futami S, Hoshi H et al. Crossed Cerebellar Diaschi-sis: Analysis of Iodine-123-IMP SPECT imaging. J Nucl Med 1995; 36:399–402.8. Catafau AM. Brain SPECT in clinical practice. Part I: Perfusion. J NuclMed 2001; 42: 259–271.9. Fukumitsu N, Tsuchida D, Ogi S, Uchiyama M, Mori M et al. Dynamicand static cerebral perfusion scintigraphy of cerebral arteriovenousmalformations. Clin Nucl Med 2003; 28: 64–65.10. Leber K, Aigner R, Nicoletti R et al. Dynamic and static evalua-tion of cerebral arteriovenous malformations to evaluate radio-surgical treatment. Stereotact Funct Neurosurg 1996; 66 (Suppl 1):269–277.

Diagnostic value of cerebral perfusion scintigraphy in evaluation of intracranial arteriovenous malformations - preliminary report

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Diagnostic value of cerebral perfusion scintigraphy in evaluation of intracranial arteriovenous malformations - preliminary report

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