-
[show abstract]
[hide abstract]
ABSTRACT: Funktionelle Bildgebungsmethoden wie die Positronenemissionstomographie (PET) oder die funktionelle Magnetresonanztomographie
(fMRT) erlauben faszinierende Einblicke in die zerebrale Schmerzverarbeitung. So haben bildgebende Verfahren maßgeblich zu
der Erkenntnis beigetragen, dass kein klar abgegrenztes „Schmerzzentrum“ existiert. Vielmehr ist ein ganzes Netzwerk zentralnervöser
Regionen an der Übertragung und Verarbeitung von Reizen beteiligt, die zu dem Sinneseindruck „Schmerz“ führen. Ausgeklügelte
Paradigmen erlauben die nähere Charakterisierung sensorischer, emotionaler und kognitiver Prozesse bei der Schmerzverarbeitung.
In dieser Übersichtsarbeit wird auf das Netzwerk von schmerzverarbeitenden Hirnstrukturen (Schmerzmatrix) eingegangen, und
ausgewählte Aspekte der somatosensorischen (Diskrimination unterschiedlicher Reizmodalitäten, noxisch vs. nichtnoxisch, Summationseffekte),
emotionalen, kognitiven (Aufmerksamkeit, Erwartung, Ablenkung), vegetativen (u.a. Homöostasekonzept) und motorischen Verarbeitung
werden dargestellt.
Functional neuroimaging methods such as positron emission tomography (PET) or functional magnetic resonance imaging (fMRI)
provide fascinating insights into the cerebral processing of pain. Neuroimaging studies have shown that no clearly defined
“pain centre” exists. Rather, an entire network of brain regions is involved in the processing of nociceptive information,
which leads to the subjective impression of “pain”. Sophisticated study designs nowadays permit the characterisation of different
components of pain processing. In this review, we summarise neuroimaging studies, which contributed to the characterisation
of these different aspects of cerebral pain processing, such as somatosensory (discrimination of different stimulus modalities,
noxious vs non-noxious, summation), emotional, cognitive (attention, anticipation, distraction), vegetative (homeostasis)
and motor aspects.
SchlüsselwörterSchmerz-Funktionelle Bildgebung-Somatosensorik-Kognition-Emotion
KeywordsPain-Functional imaging-Somatosensory system-Cognition-Emotion
Der Schmerz 04/2012; 24(2):114-121. · 0.88 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Schmerzevozierte Potenziale eröffnen eine objektive Möglichkeit, nozizeptive Bahnen zu untersuchen. Eine neuere Methode stellen
hierbei kontakthitzeevozierte Potenziale (CHEPS) dar. Diese nichtinvasive Methode eignet sich sowohl zur Untersuchung der
Integrität des peripheren schmerzverarbeitenden Nervensystems, das durch A-δ-Fasern und C-Fasern repräsentiert wird, als auch
zur Untersuchung des Tractus spinothalamicus. Im Gegensatz zu alternativen Untersuchungen wie der quantitativ sensorischen
Testung, die stark von der Mitarbeit des Patienten abhängig sind, stellen kontakthitzeevozierte Potenziale ein objektives
Verfahren dar. Dieser Artikel stellt die Methode mit Normwerten und anhand von Patientenbeispielen vor und erörtert den Stellenwert
unter Berücksichtigung der Vor- und Nachteile.
Pain evoked potentials offer a possibility for the evaluation of nociceptive pathways. Contact heat evoked potentials (CHEPS)
represent a novel technique allowing to investigate peripheral pain pathways represented by small-diameter nerve fibers (A-delta
and C fibers) and to study the spinothalamic tract. In contrast to more time-consuming methods such as quantitative sensory
testing, CHEPS enables an objective investigation of pain pathways. This article reviews and discusses the technique, possible
indications, and pitfalls in the context of clinical cases.
Der Nervenarzt 04/2012; 79(8):899-907. · 0.68 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The sensation of itch - defined as unpleasant sensation inducing the urge to scratch - is processed by a network of different brain regions contributing to the encoding of sensory, emotional, attention-dependent, cognitive-evaluative and motivational patterns. Patients with atopic eczema show different activation patterns and kinetics compared to healthy volunteers. This review summarizes current studies investigating itch in the brain.
Progress in allergy 01/2012; 98:253-65.
-
C Maier,
R Baron,
T R Tölle,
A Binder,
N Birbaumer,
F Birklein,
J Gierthmühlen,
H Flor,
C Geber,
V Huge, [......],
H Richter,
R Rolke,
A Scherens,
A Schwarz,
C Sommer,
V Tronnier,
N Uçeyler, M Valet,
G Wasner,
R-D Treede
[show abstract]
[hide abstract]
ABSTRACT: Neuropathic pain is accompanied by both positive and negative sensory signs. To explore the spectrum of sensory abnormalities, 1236 patients with a clinical diagnosis of neuropathic pain were assessed by quantitative sensory testing (QST) following the protocol of DFNS (German Research Network on Neuropathic Pain), using both thermal and mechanical nociceptive as well as non-nociceptive stimuli. Data distributions showed a systematic shift to hyperalgesia for nociceptive, and to hypoesthesia for non-nociceptive parameters. Across all parameters, 92% of the patients presented at least one abnormality. Thermosensory or mechanical hypoesthesia (up to 41%) was more frequent than hypoalgesia (up to 18% for mechanical stimuli). Mechanical hyperalgesias occurred more often (blunt pressure: 36%, pinprick: 29%) than thermal hyperalgesias (cold: 19%, heat: 24%), dynamic mechanical allodynia (20%), paradoxical heat sensations (18%) or enhanced wind-up (13%). Hyperesthesia was less than 5%. Every single sensory abnormality occurred in each neurological syndrome, but with different frequencies: thermal and mechanical hyperalgesias were most frequent in complex regional pain syndrome and peripheral nerve injury, allodynia in postherpetic neuralgia. In postherpetic neuralgia and in central pain, subgroups showed either mechanical hyperalgesia or mechanical hypoalgesia. The most frequent combinations of gain and loss were mixed thermal/mechanical loss without hyperalgesia (central pain and polyneuropathy), mixed loss with mechanical hyperalgesia in peripheral neuropathies, mechanical hyperalgesia without any loss in trigeminal neuralgia. Thus, somatosensory profiles with different combinations of loss and gain are shared across the major neuropathic pain syndromes. The characterization of underlying mechanisms will be needed to make a mechanism-based classification feasible.
Pain 09/2010; 150(3):439-50. · 5.78 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Functional neuroimaging methods such as positron emission tomography (PET) or functional magnetic resonance imaging (fMRI) provide fascinating insights into the cerebral processing of pain. Neuroimaging studies have shown that no clearly defined "pain centre" exists. Rather, an entire network of brain regions is involved in the processing of nociceptive information, which leads to the subjective impression of "pain". Sophisticated study designs nowadays permit the characterisation of different components of pain processing. In this review, we summarise neuroimaging studies, which contributed to the characterisation of these different aspects of cerebral pain processing, such as somatosensory (discrimination of different stimulus modalities, noxious vs non-noxious, summation), emotional, cognitive (attention, anticipation, distraction), vegetative (homeostasis) and motor aspects.
Der Schmerz 04/2010; 24(2):114-21. · 0.88 Impact Factor
-
F Pfab, M Valet,
T Sprenger,
J Huss-Marp,
G I Athanasiadis,
H J Baurecht,
A Konstantinow,
C Zimmer,
H Behrendt,
J Ring,
T R Tölle,
U Darsow
[show abstract]
[hide abstract]
ABSTRACT: Itch is the major symptom of many allergic diseases; yet it is still difficult to measure objectively. The aim of this study was to use an evaluated itch stimulus model in lesional (LS) and nonlesional (NLS) atopic eczema (AE) skin and to characterize cerebral responses using functional magnetic resonance imaging (fMRI).
Thermal modulation was performed on a histamine stimulus in randomized order on LS or NLS in rapid alternating order from 32 degrees C (warm) to 25 degrees C (cold). Subjective itch ratings were recorded. Additionally, fMRI measurements were used to analyze the cerebral processing (n = 13). Healthy skin (HS) of age-matched volunteers served as control (n = 9).
Mean VAS itch intensity was significantly (P < 0.0001) higher during the relative cold [55.2 +/- 8.3% (LS); 48.6 +/- 8.2% (NLS)] compared to the relative warm blocks [36.0 +/- 7.3% (LS); 33.7 +/- 7.6% (NLS)]. Compared to HS, the itch response was delayed in LS and NLS. Itch intensity was perceived highest in LS, followed by NLS and HS. For NLS, fMRI revealed at the beginning of the itch provocation a cerebral deactivation pattern in itch processing structures (thalamus, prefrontal, cingulate, insular, somatosensory and motor cortex). During the course of stimulation, the cerebral deactivation was reduced with time and instead an activation of the basal ganglia occurred. In contrast LS showed an activation instead of deactivation pattern already at the beginning of the stimulation in the above mentioned structures.
Moderate short-term temperature modulation led to a reproducible, significant enhancement of histamine-induced itch with the strongest effect in LS. The differences in itch perception and itch kinetics between healthy volunteers and NLS in patients point towards an ongoing central inhibitory activity patients with AE, especially at the beginning of the itch provocation.
Allergy 10/2009; 65(1):84-94. · 6.27 Impact Factor
-
Journal of Neurology 12/2008; 255(11):1832-3. · 3.47 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Voxel-based morphometry (VBM) has proved a powerful method to detect subtle changes of gray matter (GM) at the group level but the role of VBM for the detection of GM changes in single subjects, especially in those with suspected neurodegenerative disorder, remains uncertain. Here, we performed single subject analyses in 22 patients in early stages of Huntington disease (HD), a neurodegenerative disorder with a well-known and characteristic pattern of GM loss.
We applied an ANCOVA with age and gender as covariates and corrected for multiple statistical tests by false discovery rate (P < 0.05). Each patient was compared to 133 healthy controls. The same procedure was applied to 22 of the controls matched for age and gender in a pair-wise manner.
Our analyses yielded biologically plausible results in HD patients in which GM decrease within the caudate nucleus could be identified in 15 of the 16 most affected patients while GM decrease was found in only 1 control subject. Lowering the size of the control group yielded comparable results with 99 and 66 control subjects whereas sensitivity decreased with 33 control subjects.
Our pilot study demonstrates a potential role of VBM for the detection of cerebral GM changes in single subjects with suspected neurodegenerative disorder.
American Journal of Neuroradiology 12/2008; 30(3):539-43. · 2.93 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Mu-opioidergic agonists are believed to induce euphoria, whereas kappa-agonists are thought to lead to dysphoria. Our study investigated mood effects of remifentanil, a mu-receptor opioid agonist, in healthy male volunteers. Moreover, we examined interactions between mood and pain. Three conditions were investigated in 21 volunteers: saline, 0.05 and 0.15 microg kg(-1) min(- 1) remifentanil. Each condition was investigated during non-painful heat and during painful heat stimulation. Mood was measured with the von Zerssen's mood scale (Bf-S score) and pain intensity using a Visual Analogue Scale (VAS). High Bf-S scores are reflecting discontent and dysphoria. Changes were tested for significance using a linear mixed model approach. Remifentanil significantly increased Bf-S scores during painful heat (+91.4%), indicating a negative mood effect, although it reduced VAS scores of painful heat intensity (-49.0%). The type of sensory stimulation (non-painful versus painful) had no effect on mood. There was no interaction between remifentanil dose and type of stimulation. Our results provide evidence for negative mood effects of remifentanil. These effects occur with and without pain. Taken into account that remifentanil reduces pain, one could have expected analgesia-related amelioration of mood instead. In clinical practice, these remifentanil effects should be considered and a comedication might be advisable.
Journal of Psychopharmacology 10/2008; 24(3):355-61. · 3.04 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Idiopathic chronic pain conditions with a mismatch between anatomical abnormalities and symptoms can be categorized as somatoform pain disorder according to the DSM-IV criteria. A dysfunction of pain processing circuits has been suggested as one underlying pathophysiological factor. There is accumulating evidence for a crucial role of affect regulating brain structures such as the medial frontal cortex in this context. We investigated the cerebral processing of noxious heat stimuli as objective marker for pain sensation in 12 right handed women with somatoform pain disorder fulfilling DSM-IV criteria and 13 age-matched healthy volunteers using functional MRI. The average ratings for experimentally induced pain were not significantly different between controls and patients concerning pain intensity and pain unpleasantness. Comparing patients with controls a pain related hypoactive state of the ventromedial prefrontal/orbitofrontal cortex (BA 10/11) and a hyperactive state of the parahippocampal gyrus, amygdala and anterior insula were found in the patient group. Our findings of an altered cerebral processing of experimentally induced pain in patients with somatoform pain disorder support the hypothesis of dysfunctional pain processing, especially in affect regulating regions.
Pain 08/2008; 137(2):413-21. · 5.78 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Pain evoked potentials offer a possibility for the evaluation of nociceptive pathways. Contact heat evoked potentials (CHEPS) represent a novel technique allowing to investigate peripheral pain pathways represented by small-diameter nerve fibers (A-delta and C fibers) and to study the spinothalamic tract. In contrast to more time-consuming methods such as quantitative sensory testing, CHEPS enables an objective investigation of pain pathways. This article reviews and discusses the technique, possible indications, and pitfalls in the context of clinical cases.
Der Nervenarzt 07/2008; 79(8):899, 902-7. · 0.68 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Over the last decades, functional imaging studies have fostered our knowledge of cerebral pain processing in humans. A lively interest has been focussing on possible opioidergic mechanisms of pain transmission and modulation. Today, reliable knowledge of the in vivo distribution of opioid receptors in healthy human subjects is available from positron emission tomography (PET) studies of opioidergic neurotransmission. Gender dependent differences in receptor distribution and ligand metabolism have been demonstrated. Moreover, an increasing number of studies are reporting alterations in receptor distribution patterns in states involving painful diseases. Various acute painful challenges have also been shown to induce measurable changes in receptor availability in multiple brain areas. The perigenual anterior cingulate cortex (ACC) has been identified as one brain region with a major impact on opioidergic pain modulation. Thereby, the ACC apparently executes cortical top-down control on brainstem structures in (exogenous) pharmacological opioid analgesia. In addition, accumulating evidence suggests that non-pharmacological treatment approaches also utilize similar endogenous opioid dependent pathways to exert pain modulation. This article summarizes our current knowledge of PET studies of the opioidergic system and outlines future perspectives.
Der Schmerz 12/2007; 21(6):503-13. · 0.88 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Neuroimaging studies have explored cerebral activation patterns in patients with cluster headache (CH) during attacks and have revealed activation of multiple brain areas known to belong to the general pain-processing network. However, it is still unclear which changes in brain metabolism are inherent to the shift from the 'in bout' to the 'out of bout' period. We measured cerebral glucose metabolism in 11 episodic CH patients during the cluster and again during the remission period with (18)F-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) and compared these data with 11 healthy controls. 'In bout' compared with 'out of bout' scans were associated with increases of metabolism in the perigenual anterior cingulate cortex (ACC), posterior cingulate cortex, prefrontal cortex, insula, thalamus and temporal cortex. Decreases in metabolism were observed in the cerebellopontine area. Compared with healthy volunteers, hypometabolism in the patient group ('in bout' and 'out of bout') was found in the perigenual ACC, prefrontal and orbitofrontal cortex. Thus, FDG-PET in CH patients revealed 'in bout' activation of brain structures which are involved in descending pain control. Compared with controls, the regional brain metabolism was constitutively decreased in most of these structures, irrespective of the bout. This finding indicates a deficient top-down modulation of antinociceptive circuits in CH patients. We suggest that trigger mechanisms of CH are insufficiently controlled and thus promote the initiation of the bout period and acute attack.
Cephalalgia 10/2007; 27(9):1033-42. · 3.43 Impact Factor
-
H Laubenthal, M Valet,
T Sprenger,
A Wöller,
T R Tölle,
H Röpcke,
S Wirz,
C Schröter,
M Schiltenwolf,
P Henningsen,
T Sundermeier,
H J Ebell,
N Kohnen,
W Häuser
[show abstract]
[hide abstract]
ABSTRACT: Six articles are presented which illustrate the activities at the summer workshop "Pain and awareness" held 27-28 May 2005 in Marienfeld by the German Interdisciplinary Collaboration for Pain Therapy (DIVS). One article on pain constructs in the mind explains the advantages of functional imaging methods: these enable characterization of partial aspects of pain processing in the brain and the mechanisms that lead to chronic states of pain syndromes. A further overview explains the influence of different drugs on pain perception and various conscious states. How back pain patients experience their illness was analyzed in a study using an explanatory model interview: somatic aspects were dominant, but in three-fourths of the patients psychological illness attributions also played a role. A summary from the perspective of religious history and theology explores how pain is interpreted and accepted in various religious communities. Another article addresses hypnosis as a complementary technique to anesthesia procedures in surgical medicine, for treating chronic pain and experimental acute pain. The last contribution deals with how people in different cultures experience pain: ethnocentric bias can lead to difficulties in communication and misjudgments when treating foreign-born patients. All in all the workshop highlighted important formative factors in pain processing in a condensed form and offered stimulating perspectives for this area of pain research and future treatment options.
Der Schmerz 07/2007; 21(3):238-44, 246-62. · 0.88 Impact Factor
-
H. Laubenthal, M. Valet,
T. Sprenger,
A. Wöller,
T.R. Tölle,
H. Röpcke,
S. Wirz,
C. Schröter,
M. Schiltenwolf,
P. Henningsen,
T. Sundermeier,
H.J. Ebell,
N. Kohnen,
W. Häuser
[show abstract]
[hide abstract]
ABSTRACT: Insgesamt 6 Beitrge des Sommerworkshops Schmerz und Bewusstsein der Deutschen Interdisziplinren Vereinigung fr Schmerztherapie e.V. (DIVS) am 27./28. Mai 2005 in Marienfeld werden exemplarisch vorgestellt. Ein Beitrag ber die Schmerzdarstellung im Gehirn legt die Vorteile funktioneller Bildgebungsmethoden dar: Diese erlauben die Charakterisierung von Teilaspekten der zerebralen Schmerzverarbeitung und Mechanismen der Chronifizierung bei Schmerzsyndromen. Ein weiterer berblick erlutert den Einfluss unterschiedlicher Analgetika, Sedativa und Ansthetika auf die unterschiedlichen Bewusstseinszustnde. Das Krankheitserleben von Rckenschmerzenpatienten wird in einer Studie mit Hilfe des Erklrungsmodell-Interviews untersucht: Somatische Aspekte dominieren dabei; fr 3/4 der Patienten spielen aber auch psychische Ursachenvorstellungen eine Rolle. Wie Schmerz in verschiedenen Religionsgemeinschaften interpretiert und akzeptiert wird, zeigt eine religionsgeschichtlich-theologische bersicht. Ein weiterer Beitrag stellt die Wirksamkeit der Hypnose als ergnzende Manahme ansthesiologischer Verfahren in der operativen Medizin, bei chronischen Schmerzen und bei experimentellem Akutschmerz dar. Mit dem Schmerzerleben in verschiedenen Kulturen beschftigt sich der letzte Beitrag: Eine einseitige ethnozentristische Sicht kann demnach zu Verstndigungsschwierigkeit und Fehlurteilen bei der Behandlung auslndischer Patienten fhren. Der Workshop beleuchtete insgesamt in konzentriertem Rahmen wichtige Gestaltungsfaktoren der Schmerzverarbeitung und gab stimulierende Ausblicke auf diesen Teil der Schmerzforschung und knftige Therapiemglichkeiten.Six articles are presented which illustrate the activities at the summer workshop Pain and awareness held 27–28 May 2005 in Marienfeld by the German Interdisciplinary Collaboration for Pain Therapy (DIVS). One article on pain constructs in the mind explains the advantages of functional imaging methods: these enable characterization of partial aspects of pain processing in the brain and the mechanisms that lead to chronic states of pain syndromes. A further overview explains the influence of different drugs on pain perception and various conscious states. How back pain patients experience their illness was analyzed in a study using an explanatory model interview: somatic aspects were dominant, but in three-fourths of the patients psychological illness attributions also played a role. A summary from the perspective of religious history and theology explores how pain is interpreted and accepted in various religious communities. Another article addresses hypnosis as a complementary technique to anesthesia procedures in surgical medicine, for treating chronic pain and experimental acute pain. The last contribution deals with how people in different cultures experience pain: ethnocentric bias can lead to difficulties in communication and misjudgments when treating foreign-born patients. All in all the workshop highlighted important formative factors in pain processing in a condensed form and offered stimulating perspectives for this area of pain research and future treatment options.
Der Schmerz 05/2007; 21(3):238-262. · 0.88 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In Huntington disease (HD), both the genetic defect and mutant gene product huntington are known but the exact mechanisms that lead to neuronal loss are poorly understood. Until now, the distribution of tissue loss throughout the brain has been investigated intensively. Here we searched for areas that, antipodal to the striatum, display grey-matter (GM) preservation. We performed high resolution T1-weighted magnetic resonance imaging and voxel-based morphometry in 46 patients in early HD and 46 healthy controls. We applied an analysis of covariance (ANCOVA) model with the total GM volume of each participant as covariate. In accordance with earlier reports, group comparisons revealed GM decrease in the striatum, insula, and thalamus as well as in dorsolateral frontal and occipital areas. In contrast, the limbic prefrontal cortex displayed GM preservation. Our findings support hypotheses that postulate differential involvement of frontosubcortical circuits in the pathophysiology of HD.
Acta Neurovegetativa 04/2007; 114(3):367-72. · 2.73 Impact Factor
-
R Rolke,
R Baron,
C Maier,
T R Tölle,
R-D Treede,
A Beyer,
A Binder,
N Birbaumer,
F Birklein,
I C Bötefür, [......],
R Klug,
G B Landwehrmeyer,
W Magerl,
C Maihöfner,
C Rolko,
C Schaub,
A Scherens,
T Sprenger, M Valet,
B Wasserka
[show abstract]
[hide abstract]
ABSTRACT: The nationwide multicenter trials of the German Research Network on Neuropathic Pain (DFNS) aim to characterize the somatosensory phenotype of patients with neuropathic pain. For this purpose, we have implemented a standardized quantitative sensory testing (QST) protocol giving a complete profile for one region within 30 min. To judge plus or minus signs in patients we have now established age- and gender-matched absolute and relative QST reference values from 180 healthy subjects, assessed bilaterally over face, hand and foot. We determined thermal detection and pain thresholds including a test for paradoxical heat sensations, mechanical detection thresholds to von Frey filaments and a 64 Hz tuning fork, mechanical pain thresholds to pinprick stimuli and blunt pressure, stimulus/response-functions for pinprick and dynamic mechanical allodynia, and pain summation (wind-up ratio). QST parameters were region specific and age dependent. Pain thresholds were significantly lower in women than men. Detection thresholds were generally independent of gender. Reference data were normalized to the specific group means and variances (region, age, gender) by calculating z-scores. Due to confidence limits close to the respective limits of the possible data range, heat hypoalgesia, cold hypoalgesia, and mechanical hyperesthesia can hardly be diagnosed. Nevertheless, these parameters can be used for group comparisons. Sensitivity is enhanced by side-to-side comparisons by a factor ranging from 1.1 to 2.5. Relative comparisons across body regions do not offer advantages over absolute reference values. Application of this standardized QST protocol in patients and human surrogate models will allow to infer underlying mechanisms from somatosensory phenotypes.
Pain 09/2006; 123(3):231-43. · 5.78 Impact Factor
-
T Sprenger,
F Willoch,
M Miederer,
F Schindler, M Valet,
A Berthele,
M E Spilker,
S Förderreuther,
A Straube,
I Stangier,
H J Wester,
T R Tölle
[show abstract]
[hide abstract]
ABSTRACT: Using PET with the opioidergic ligand [11C]diprenorphine, the authors demonstrate decreased tracer binding in the pineal gland of cluster headache patients vs healthy volunteers. Opioid receptor availability in the hypothalamus and cingulate cortex depended on the duration of the headache disorder. Therefore, the pathophysiology of cluster headache may relate to opioidergic dysfunction in circuitries generating the biologic clock.
Neurology 05/2006; 66(7):1108-10. · 8.31 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We report headache induced BOLD changes in an atypical case of trigeminal autonomic cephalgia (TAC). A 68-year-old patient was imaged using fMRI during three attacks of a periorbital head-pain with a average duration of 3 min. During the attacks, left sided conjunctival injection, rhinorrhea, lacrimation, facial sweating and hypersalivation were apparent. These attacks were usually partly responsive to oxygen administration but otherwise refractory to any drug. The patient described either attacks with a duration of one minute or less or longer attacks persisting for maximum of 20 min with headaches occurring up to 100 times a day. When considering the symptoms, frequency, duration and therapeutic response of the patient's headache, no clear-cut classification to one of the subtypes of trigeminal autonomic cephalgias (cluster headache, paroxysmal hemicrania, SUNCT) or trigeminal neuralgia was possible. The cerebral activation pattern was similar but not identical to those previously observed in cluster headache and SUNCT with a prominent activation in the hypothalamic grey matter. This case study underlines the conceptual value of the term TAC for the group of headaches focusing around the trigeminal-autonomic reflex. Our results emphasize the importance of the hypothalamus as key region in the pathophysiology of this entity.
Cephalalgia 10/2004; 24(9):753-7. · 3.43 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The psychophysiological effect of different modes of manual acupuncture stimulation was investigated in 12 healthy, right handed, male subjects (mean age 29). The cerebral blood flow velocity (CBFV) in both middle cerebral arteries, arterial blood pressure (BP), heart rate (HR) and the perceived intensity of the stimulation were monitored while an acupuncture needle in the right dorsal thenar muscle (point Hegu, Li 4) was repetitively rotated with either high frequency (4-8 Hz) and low amplitude (hf-la) or low frequency (1-2 Hz) and high amplitude (lf-ha). Response patterns induced by hf-la and 1f-ha [corrected] stimulation differed significantly (P < 0.05) as tested by Student's t-test: (1), 1f-ha [corrected] stimulation was perceived as more intense and induced a more marked right hemispheric CBFV increase; (2), while hf-la stimulation lead to a slight decrease of BP and HR, lf-ha stimulation induced an initial pressor response (increase of BP, decrease of HR) and a more marked long term decrease of BP. Data indicate that the mode of manual acupuncture stimulation has a differential effect on the perceived stimulation intensity, the cerebral activation and the cardiovascular reflex response.
Neuroscience Letters 12/2002; 333(3):203-6. · 2.11 Impact Factor
