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Make Love to Forget Two Cases of Transient Global Amnesia

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					                                                              Coll. Antropol. 28 (2004) 2: 899–905
                                                                               UDC 616.69:618.17
                                                                          Original scientific paper




Make Love to Forget: Two Cases of
Transient Global Amnesia Triggered
by Sexual Intercourse

Mira Bu~uk, Amir Muzur, Ksenija Willheim, Ante Jurjevi}, Zoran Tomi}
and Lidija Tu{kan-Mohar
Department of Neurology, University Hospital Rijeka, Rijeka, Croatia



ABSTRACT

   Transient global amnesia (TGA) is characterized by a sudden onset and by a typical
resolution within several hours. Several precipitating events have been proposed: physi-
cal exertion, emotional experiences, etc. The aim of this paper was to present two cases of
TGA triggered by sexual intercourse and to suggest a possible mechanism for the devel-
opment of TGA. In both patients, clinical examination revealed elevated blood pressure.
Laboratory examinations and brain CTs were normal. EEG demonstrated diffuse dysr-
hythmia and slow spike-waves, respectively. SPECT revealed hypoperfusion in the left
frontal and right medial temporal regions. Various explanations of the mechanism of TGA
are discussed. Based on the observed hypoperfusion in the medial temporal regions, a
new hypothesis is advanced, suggesting the possibility that TGA occurs due to a patho-
logically changed or less adaptable anterior chorioid artery, initially constricted by
hypotension following a blood shift from the center towards periphery.

   Keywords: transient global amnesia, memory, sexual intercourse, anterior chorioid
artery



Introduction

    Transient global amnesia (TGA) is cer-      duration of an episode has been estima-
tainly one of those states that create mo-      ted at 6–7 hours, ranging from 15 minutes
re impression than real harm, both to the       to 7 days1. Due to difficulties in learning
patient and to his/her surrounding. This        new contents, the patients repetitively
distinctive form of amnesia is characteri-      ask questions and look extraordinarily
zed by a sudden beginning and a typical         confused2, although general cognition se-
resolution within several hours. Mean           ems intact.


Received for publication March 10, 2003


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M. Bu~uk et al.: Sex and Transient Global Amnesia, Coll. Antropol. 28 (2004) 2: 899–905

    Numerous cases have been described           Neurology due to a suddenly appeared
since the first recognition in 1950-s and        memory disturbance. The patient repor-
the coinage of the term a decade later3.         ted that her companion had visited her
The majority of the reports mention dis-         that day about 10 a.m. They had had sex-
turbances in the recall of recent memo-          ual intercourse but she could not remem-
ries, with rare or no difficulties in the ret-   ber the details. She could not remember
rieval of remote events. Unlike episodic         when her partner had left. Her close
memory, immediate and semantic memo-             friend, who accompanied her to the Hos-
ries seem to be preserved3. According to         pital, told the physician that she had co-
certain reports, other cognitive functions       me to the patient’s house about 1 p.m.
also may be slightly disturbed4. Follow-         The patient was upset, repeating the sa-
up of patients’ memory functions demon-          me questions: »Where am I?«, »What hap-
strates that after the disturbance was re-       pened to me?«, »What day is today?«, etc.
solved, a complete amnesia typically is          She seemed confused and could not re-
present for the period of TGA and a short        member the partner’s name or what was
period before it4. Several precipitating         his job. She did recognize her friend, who
events have been proposed: besides phys-         kept answering her questions. After two
ical exertion5 and highly emotional expe-        hours, the patient gradually calmed down.
riences6, exposure to cold/heat3, exposure       When she understood that she had not
to high altitude7, mild head trauma, and         been able to remember a period of several
many other have been mentioned5,8. Cer-
                                                 hours, she got frightened and decided to
tain potential risk factors have also been
                                                 visit her physician, who referred her to
pointed out, like hypertension, ischemic
                                                 the neurologist. The patient was admit-
cardiac disease, or migraine8,9.
                                                 ted at 4 p.m. Clinical neurological exami-
    One of the curiosities is the revelation     nation demonstrated no focal deficit. She
of sexual intercourse as a possible precip-
                                                 had amnesia for a period of five hours,
itating factor for TGA10,11. This relation
                                                 while her retrograde amnesia disappea-
does not seem to be rare at all. In a study
                                                 red. Her blood pressure was 150/ 110
by Fisher6. precipitating factors were rec-
                                                 mmHg; routine blood tests and coagulog-
ognized in 26 out of 85 spells: out of those
                                                 ram were normal. A routine neuropsycho-
26, 7 were connected with sexual inter-
                                                 logical battery, administrated about five
course. In two cases described by Fisher
                                                 hours after the beginning of the attack,
and Adams3, patients experienced TGA
at the climax of sexual intercourse, sud-        revealed no deficits except in the realm of
denly asking »Where am I? What’s happe-          episodic memory (Table 1). Administrated
ned?« and other questions typical for TGA12.     approximately seven hours after the onset
                                                 of the disturbances, singlephoton emission
    Stirred up by two observed cases of
                                                 tomography (SPECT) detected hypoperfu-
TGA triggered during sexual intercourse,
we decided to further investigate that           sion in the left frontal and right medial
connection and to attempt to benefit from        temporal regions. The electroencephalog-
it in contributing to the elucidation of the     raphy (EEG), applied on the next day,
pathological condition of TGA, but also of       showed moderate diffuse dysrhythmia,
human memory processes in general.               while computerized tomography (CT) of
                                                 the brain was normal SPECT and neurop-
                                                 sychological tests were re-administered
Results
                                                 after seven days, and revealed no abnor-
Case 1                                           malities. After six months, a repeated
   A 55-year old teacher, accompanied by         EEG resulted normal and the patient felt
her friend, came to the Department of            generally well.

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      M. Bu~uk et al.: Sex and Transient Global Amnesia, Coll. Antropol. 28 (2004) 2: 899–905

                                    TABLE 1
      NEUROPSYCHOLOGICAL ASSESSMENT: AT 5 HOURS (CASE 1) AND 7 HOURS (CASE 2),
                     RESPECTIVELY, AFTER THE ONSET OF TGA

 Patient    Sex     Age     Orientation in     Digit       Semantic memory:           Episodic
                             time/space*       span†     famous facts & faces‡        memory#
 NN          F       55        4/7 (7/7)      6 (6±2)        12/14 (12±2)            4/13 (12±1)
 VD          M       63        3/7 (7/7)      6 (6±2)        13/14 (12±2)            2/13 (12±1)

Note: The values in parentheses correspond to an age- and education matched ad-hoc control
group (N=16). All the fractions in the Table represent the ratio between the result obtained by the
patient and the maximal score for the given test.
* To test the patient’s orientation in time/space, the first seven questions from the Galveston Ori-
entation Amnesia Test (GOAT) were used.13
† Short-term memory was tested by applying the Digit Span Test from the Wechsler Intelligence
Scales.13
‡ Semantic memory was tested by asking about 7 widely-known facts (e.g., the capital of Croatia)
and presenting the patient with the photographs of 7 widely-known personalities (e.g. Charlie
Chaplin) and requiring to name them.
# Episodic (autobiographic) memory was tested by asking questions regarding the immediate past
(the last 24 hours). The correctness of the reported was established by confronting the answers gi-
ven by the patients to those provided by the family members.




Case 2                                             rade amnesia. A routine neuropsychologi-
                                                   cal battery was applied seven hours after
   A retired 63-year old policeman was             the onset of the disturbances, revealing
admitted to our Hospital due to memory             no defects but in the realm of episodic me-
disturbances. His wife, who accompanied            mory (Table 1). SPECT examination per-
him, reported that he had felt well that           formed about eight hours after the onset
morning. He had always been in good                of the attack demonstrated hypoperfu-
health. They had a sexual intercourse at           sion in the medial temporal region bilate-
about 8.30 a.m. Soon afterwards, he felt           rally. After two hours, brain CT was made
pressure in his head, but the feeling dis-         and was found normal. EEG, made two
appeared a few minutes later. She noticed          days later, demonstrated diffuse slow spi-
that he had become confused and kept re-           ke-waves. Both SPECT and neuropsycho-
peating: »Where am I?« »What happened              logical tests were repeated after 7 days
to me?«. He was very excited. On his way           and revealed no abnormalities. Three
to the hospital, he gradually calmed               months later, his EEG was normal and
down. Upon his arrival to the hospital, at         the patient felt generally well.
about 1. p.m., he was submitted to a neu-
rological examination but no focal neuro-             In both cases, the technetium-labeled
logical deficit was detected. He lost his          hexamethil-propylene-amine-oxime SPECT
memory for a period of approximately               technique was applied and the analysis
three hours. He did not complain of head-          was performed using anatomically defi-
ache. He could not remember the sexual             ned regions of interests. Hypoperfusion
intercourse or his arrival to the hospital.        was determined by comparing z-scores of
His blood pressure was 160/100 mmHg.               each of our patients to those of the control
Blood tests and coagulogram were nor-              group. The control group (N=16) matched
mal. He demonstrated no trace of retrog-           our two cases in sex and age.

                                                                                               901
M. Bu~uk et al.: Sex and Transient Global Amnesia, Coll. Antropol. 28 (2004) 2: 899–905

Discussion                                      might reflect the difference among the
                                                symptoms observed (primarily the pres-
   There are at least two issues to be dis-     ence or absence of retrograde amnesia,
cussed when considering the pathophy-           but also the presence or absence of the al-
siology of TGA: the nature of the phenom-       teration of cognitive functions other than
enon and its localization. If we suppose        memory4). Kapur et al.20 suggested that
that not mild head trauma, but physical         the »recovery of some types of human am-
exertion, emotional experience and pain         nesia, such as that associated with TGA,
connected with it, may be the cause of          follows a 'lateral-to-medial' rule – lateral
TGA, then we will agree that the majority       inferotemporal areas that play a major role
of precipitating factors described (includ-     in retrograde amnesia recover first from
ing migraine, physical exertion, highly         hypometabolism related to the TGA at-
emotional experience, sexual intercourse,       tack, followed by 'interface' areas such as
thermal shock), could be reduced to tem-        the rhinal and parahippocampal cortices
porary disturbance of cerebral circula-         that are considered to have a role in both
tion. The hypothetical circulatory distur-      anterograde and retrograde memory fun-
bance must occur in a pathologically            ctioning, with the last areas to recover
changed or at least in a less adaptive vas-     physiological integrity being discrete lim-
cular system. Recently also was sugges-         bic-diencephalic structures such as the
ted that a (physiological) Valsalva ma-         hippocampus.« To this interpretation, one
neuver, »blocking venous return through         has to add the possibility that only ante-
the superior vena cava, may allow brief         rograde memory might be deficient in TGA.
retrograde transmission of high venous             Recent interpretations of data obtai-
pressure from the arms to the cerebral          ned by functional magnetic resonance im-
venous system, resulting in venous ische-       aging (fMRI) suggest that the recruitment
mia to the diencephalon or mesial tempo-        of fronto-parietal areas during the am-
ral lobes and to TGA«14.                        nestic state (typically associated with the
    The second issue regards the localiza-      temporolimbic circuit) may signify »a
tion. It was suggested that TGA is due to       compensatory reliance on visuospatial or
transient vascular insufficiency of arter-      working memory strategies«21.
ies supplying the medial temporal lobe9,            The data reported by Eustache et al.22
the right basal ganglia and left temporal       connect TGA with a deficit in the encod-
lobe15, or due to hypoperfusion of the tem-     ing/storage, but not in the retrieval of in-
poro-basal region16. Examinations with          formation. This speaks in favor of the as-
SPECT and positron emission tomogra-            sumption that the structures altered in
phy (PET) revealed quite inconsistent fin-      TGA are not in the frontal, but in the me-
dings4,17,18. This incongruity could provoke    dial temporal region. More precisely, if we
only a vague idea about the pathoanatomy        accept that perirhinal and entorhinal cor-
of TGA. Goldenberg4 devotes a lot to the        tices are important for recognition memo-
possible thalamic origin of TGA, advocat-       ry23, while the hippocampus itself is res-
ing especially the mediodorsal thalamic/        ponsible for episodic memory24, combining
dorsal diencephalic engagement19. In our        semantic knowledge with a temporo-spa-
first case, SPECT revealed hypoperfusion        tial context, then one highly speculative
changes both in the fronto-basal cortical       possibility remains that the circulatory
region (left) and in the medial temporal        system feeding the hippocampus (ante-
one (right). It really could be that various    rior chorioid artery; AChA) is the site
regions contribute to the symptomatology        where the changes characteristic for TGA
of TGA: the difference among the findings       occur. Although quite logical, this hypoth-

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     M. Bu~uk et al.: Sex and Transient Global Amnesia, Coll. Antropol. 28 (2004) 2: 899–905

esis contains several weak points. The         authors have proposed a glutamate-elicited
pattern observed in our SPECT results,         »spreading depression«27, that is, a self-
for instance, with hypoperfusion in the        -spreading front of depolarization associ-
frontal and medial temporal regions, was       ated by a depression of the neuronal bioe-
much larger than the territory supplied        lectrical activity for a period of minutes1.
by the AChA. Additionally, the pathop-         Inzitari et al.28, on the other hand, sug-
hysiological mechanisms that should re-        gested hyperventilation and an abnormal
sult in an isolated vasoconstriction of the    rise in the blood lactate concentration as
AChA are not so easy to understand. If         a possible cause of TGA. However, it is a
one suggested a more general vasocon-          real challenge trying to connect the phe-
striction in our two patients (e.g. a mig-     nomena advocated by the two hypothe-
raine equivalent), the absence of additio-     ses, with so many and seemingly so vari-
nal symptoms is difficult to explain. Some     ous precipitating factors, as well as with
other studies using SPECT to assess            the fact that the most typical duration of
brain perfusion during TGA have demon-         TGA, according to the literature, is up to
strated different cerebral-blood-flow (CBF)    24 hours29. Some anamnestic data indeed
alterations in medial temporal15 and tha-      suggest more generalized circulatory un-
lamic regions16. One has to note also that,    derpinnings (facial pallor one hour from
»as SPECT assesses only CBF, which may         the onset: case 4; blood on the towel: case
be unmatched to synaptic dysfunction in        2 in Fisher and Adams3). In both our pa-
acute pathological circumstances, it may       tients, heightened blood pressure was de-
provide misleading information about the       tected at the moment of hospitalization.
neurobiological basis of memory dysfunc-       The fact that both our patients were struck
tion in TGA, and incomplete information        by TGA during sexual intercourse, sug-
about its mechanisms«17. Using PET and         gests the possibility that the blood shift
measurements of CBF and oxygen meta-           from the center (brain) towards the perip-
bolism might prove to be more valuable         hery, occurred during the intercourse,
in this context17. Additional criticism to     might have provoked insufficient circula-
the »AChA hypothesis« might be that the        tion and constriction of AChA. Since pat-
typical clinical picture of an occlusion of    hologically changed or less adaptable, the
the AChA has been described to consist of      artery did not restore its normal diame-
hemiparesis, hemisensory loss, and hemi-       ter after the blood pressure came back to
anopia25, or pseudobulbar palsy, mutism,       its normal values, but continued to im-
and quadriparesis in the cases of bilate-      properly feed the target tissue, unable to
ral AChA infarction26. One might argue,        function. The diameter and alimentation
of course, that a temporary dysfunction is     were restored only after a few hours. The
pathophysiologically quite a different en-     possibility that TGA occurs due to the
tity than infarction. In order to discern      Valsalva effect14 is favored by the well-
the two states and rule out small infar-       known observations that some patients
ctions of the amygdaloid nucleus or the        complain of headache triggered during
hippocampus, one should perform MRI,           sexual intercourse. Moreover, two recent
which, unfortunately, was not possible in      investigations using color sonography and
our case. Certainly, more observation and      ultrasound venography observed a signifi-
diagnostic comparisons are needed to es-       cantly higher rate of incompetent jugular
tablish the neural underpinnings of the        valves in TGA patients as compared to a
TGA phenomenology.                             control group30,31, which strengthens the
                                               hypothesis for jugular valve incompeten-
   As far as it concerns the mechanism of      ce as the pathological condition for the
the (temporary) ischemia in TGA, some          development of TGA.

                                                                                        903
M. Bu~uk et al.: Sex and Transient Global Amnesia, Coll. Antropol. 28 (2004) 2: 899–905

    The gradual closing of the memory                        Recently, a relation between TGA and
gap, with coming back of the information                 dissociative disorders has been proposed
from the near past first (case 4 in Fisher               (»psychogenic amnesia«33). Although the
and Adams3), as well as senseless motor                  relatively young age of our Case 1 (55
actions (washing hands, going up and                     years) might suggest such a pathological
down stairs) reminding of stereotypias                   entity, it is to be noticed that environmen-
characteristic for partial-complex epilep-               tally induced stress and trauma, typically
sy, are only some of the marginal TGA-re-                associated with psychogenic amnesia34,35,
lated observations which certainly would                 were not reported by either of our two pa-
be worthy of further examination and                     tients.
which may suggest something about the                        The general idea of this article has
organization of human memory system                      certainly not been to solve one of the most
as well.                                                 intriguing mysteries of modern neurology
    EEG findings in both our patients                    – TGA, but to pinpoint some phenomena
might also indicate the epileptic TGA.                   and to suggest some ideas on their mech-
However, it is known that patients suffer-               anism. Our hypothesis about the changes
ing from epileptic amnestic seizures are                 in the circulatory system feeding the hip-
quiet during the seizure since they are                  pocampus as a possible locus of TGA pat-
not aware what is happening to them.                     hology, according to our opinion, may be
They do not experience retrograde amne-                  worthy of further investigation.
sia and the attacks are briefer than the
TGA attacks32. Our patients, on the other
hand, were aware of disturbances, suffe-
red retrograde amnesia, and their attacks                Acknowledgment
lasted for several hours. Neither ever be-
fore nor after several months or even a                     The authors express their deep grati-
year from the TGA episode they have not                  tude to Professor Juraj Sep~i} for his kind
experienced any disturbances of consci-                  help in advising the authors and sharing
ence or memory.                                          with them his rich clinical experience.



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M. Bu~uk

Department of Neurology, Clinical Hospital Center Rijeka, Rijeka University School of
Medicine, Kre{imirova 42, 51 000 Rijeka, Croatia



VODITE LJUBAV DA BI ZABORAVILI – DVA SLU^AJA TRANZITORNE
GLOBALNE AMNEZIJE POTAKNUTE SPOLNIM ODNOSOM



SA@ETAK

    Tranzitorna globalna amnezija (TGA) odlikuje se naglim nastupom i tipi~no se gubi
nakon nekoliko sati. U literaturi se spominje nekoliko precipitiraju}ih ~imbenika: fi-
zi~ka iscrpljenost, sna`no emotivno iskustvo i dr. Namjera je ovog ~lanka prikazati dva
slu~aja TGA koju je potaknuo spolni odnos i sugerirati mogu}i mehanizam razvoja ove
bolesti. U oba bolesnika klini~kim je pregledom otkriven povi{eni krvni tlak. Laborato-
rijska su se ispitivanja i CT mozga pokazali normalnima. EEG je otkrio difuznu disrit-
miju odnosno spore komplekse {iljak-val. SPECT je pokazao hipoperfuziju lijeve ~eone
i desne medijalne sljepoo~ne regije. U ~lanku se raspravlja o razli~itim hipotezama
nastanka TGA. Na temelju opa`ene hipoperfuzije medijalnih temporalnih podru~ja,
predla`e se nova hipoteza koja ukazuje na mogu}nost da je TGA posljedica patolo{ki
promijenjene ili slabije prilagodljive prednje korioidne arterije, koja, uslijed pomaka
krvi iz sredi{ta prema periferiji, prolazi kroz inicijalnu hipertoni~ku konstrikciju.




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