I Kavuk

University of Duisburg-Essen, Essen, North Rhine-Westphalia, Germany

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Publications (22)46.31 Total impact

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    ABSTRACT: This study investigated the utility of pain-related evoked potentials (PREP's) elicited by a nociceptive electrical stimulation of the skin (= electrically evoked nociceptive potentials) in early detection of diabetic small-fiber neuropathy. We studied 36 'young' (19-35 years) and 24 'older' (36-65 years) healthy subjects as well as 35 patients (35-64 years) with diabetes and neuropathic symptoms and 22 patients (34-64 years) with diabetes without neuropathic symptoms. Only patients with normal standard nerve conduction testing were included. In patients with neuropathic symptoms, we found a significant increase in PREP latencies and decrease of amplitudes elicited from both, upper and lower limbs. In non-symptomatic diabetic patients, we observed PREP abnormalities from lower limbs only. These data suggest that the method of pain-related evoked potentials elicited by a nociceptive electrical stimulation of the skin may contribute to the early detection of diabetic sensory neuropathy.
    European Journal of Neurology 02/2010; 17(6):834-41. · 4.16 Impact Factor
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    ABSTRACT: Problems related to the central nervous system may have major impact on morbidity and mortality. The aim of this retrospective study was to evaluate the nature and incidence of serious neurologic events in patients following liver transplantation. Between January 2001 and May 2004, 168 patients (105 female, 63 male) requiring transplantation for alcoholic cirrhosis, hepatitis B and C, and acute liver failure were admitted to the Intensive Care Unit (ICU) of University Hospital Essen after liver transplantation. We identified the reason for the neurologic events, the underlying disease, type of immunosuppression, and the survival rate. Severe neurologic events occurred in 46 (27.3%) of the patients. The length of stay of these patients in the ICU (18.4 +/- 19.7 days) was longer in comparison to the total patients (8.3 +/- 9.5 days, p < 0.05). The most common neurological complications were encephalopathy (18.5%) and seizures (5.4%). The survival rate after liver transplantation with neurological events was lower compared to patients without, but not significantly different (73.9 vs. 79.5%). The calcineurin inhibitor used had no impact on neurological events [cyclosporine (25.5%); tacrolimus (32.5%)]. There was a high incidence of serious neurologic events after liver transplantation. The major neurologic manifestation in our patients was encephalopathy followed by seizures.
    Archives of Medical Research 01/2007; 38(1):75-9. · 2.08 Impact Factor
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    ABSTRACT: The aim of this research was to study the prevalence of chronic headache (CH) and associated socio-cultural factors in Turkish immigrants and native Germans. Five hundred and twenty-three Turkish and German company employees were screened using a standard questionnaire. Those who suffered from headaches were also examined by a neurologist. Complete data were available for 471 (90%) subjects. Thirty-four participants (7.2%) had CH. Two independent factors for association with CH could be identified: overuse of acute headache medication (OR = 72.5; 95% CI 25.9-202.9), and being a first-generation Turkish immigrant compared with native Germans (OR = 4.4; 95% CI 1.4-13.7). In contrast, the factor associated with chronic headache was not increased in second-generation Turkish immigrants. Medication overuse was significantly more frequent in first-generation Turkish immigrants (21.6%) compared with second-generation Turkish immigrants (3.3%) and native Germans (3.6%; chi(2) = 38.0, P < 0.001). First-generation Turkish immigrants did not contact headache specialists at all, compared with 2.8% of second-generation Turkish immigrants and 8.8% of native Germans (chi(2) = 118.4, P < 0.001). Likewise no first-generation Turkish immigrant suffering from CH received headache preventive treatment, compared with 6.6% of native Germans (chi(2) = 19.1, P = 0.014). The data from this cross-sectional study reveal a high prevalence of chronic headache as well as a very low utilization of adequate medical care in first-generation Turkish immigrants in Germany.
    Cephalalgia 10/2006; 26(10):1177-81. · 3.49 Impact Factor
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    ABSTRACT: Vertebral artery dissection (VAD) has been observed in association with chirotherapy of the neck. However, most publications describe only single case reports or a small number of cases. We analyzed data from neurological departments at university hospitals in Germany over a three year period of time of subjects with vertebral artery dissections associated with chiropractic neck manipulation. We conducted a country-wide survey at neurological departments of all medical schools to identify patients with VAD after chirotherapy followed by a standardized questionnaire for each patient. 36 patients (mean age 40 + 11 years) with VAD were identified in 13 neurological departments. Clinical symptoms consistent with VAD started in 55% of patients within 12 hours after neck manipulation. Diagnosis of VAD was established in most cases using digital subtraction angiography (DSA), magnetic resonance angiography (MRA) or duplex sonography. 90% of patients admitted to hospital showed focal neurological deficits and among these 11 % had a reduced level of consciousness. 50% of subjects were discharged after 20 +/- 14 hospital days with focal neurological deficits, 1 patient died and 1 was in a persistent vegetative state. Risk factors associated with artery dissections (e. g. fibromuscular dysplasia) were present in only 25% of subjects. In summary, we describe the clinical pattern of 36 patients with vertebral artery dissections and prior chiropractic neck manipulation.
    Journal of Neurology 07/2006; 253(6):724-30. · 3.58 Impact Factor
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    ABSTRACT: Neurological disorders of different etiology may cause identical clinical symptoms requiring additional diagnostic procedures for a precise differential diagnosis. Focal epileptic seizures have been shown to cause increased signal intensities in T2 and diffusion-weighted magnetic resonance images (MRI), mimicking other neurological disorders or diseases such as viral encephalitis. In some cases even the combination of neuroimaging and cerebrospinal fluid (CSF) analysis is not sufficient to obtain the final diagnosis, since epileptic seizures may cause pleocytosis as well. Some epilepsy centers presented cases of focal status epilepticus with severe but reversible MRI changes. These cases indicate that MRI-changes following focal seizures are reversible over a different time window compared to MRI changes associated with other etiologies, such as viral infection. This data further suggest that in cases where focal seizures can not be ruled out, a follow-up MRI scan within a few days following the onset of symptoms significantly improves the precision of the differential diagnosis. Recently new scientific data were reported in this review.
    European journal of medical research 07/2005; 10(6):243-6. · 1.10 Impact Factor
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    ABSTRACT: Inappropriate use of headache medication (>15 times/month) for the treatment of headache episodes may contribute to the development of chronic headache which is refractory to most treatments. Physicians experienced in the treatment of migraine and other headaches are well aware that the daily intake of antipyretic or antiinflammatory analgesics, opioids, ergot alkaloids and "triptans" may result in chronic daily headache. Conversely, if a patient complains of chronic headache and takes pain medication every day, this headache is most likely to be caused and sustained by the medication and will vanish or improve with abstinence. Treatment includes drug withdrawal followed by structured acute therapy and initiation of migraine prophylactic treatment.
    European journal of medical research 01/2005; 9(12):565-9. · 1.10 Impact Factor
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    ABSTRACT: The adequate management of brain dead donors on an Intensive Care Unit (ICU) is one of the major key points for a successful transplantation of harvested organs. In addition to an invasive monitoring like in any other ICU patient these patients needs a meticulous attention to their hemodynamic. The early administration of desmopressin to treat diabetes insipidus, a differentiated use of fluid resuscitation and a distinct catecholamine support are special features of an appropriate basic treatment. The administration of corticoids has to be considered if a sufficient circulation can not be regained.
    European journal of medical research 11/2004; 9(10):485-90. · 1.10 Impact Factor
  • Journal of Neurology 10/2004; 251(9):1156-7. · 3.58 Impact Factor
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    European journal of medical research 06/2004; 9(5):285. · 1.10 Impact Factor
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    ABSTRACT: Acute liver failure represents one of the most challenging conditions in intensive care treatment. In most cases there is no causal medical therapy available for survive making the intensive care treatment as the most important management tool, as bridge to transplant or still the recovery of the liver! These patients frequently develop multi-organ failure, placing them at risk of hemodynamic disorder, cerebral edema, coagulopathy and various renal and metabolic complications.
    European journal of medical research 06/2004; 9(5):261-6. · 1.10 Impact Factor
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    ABSTRACT: While questioning patients about aggravation of the headache by routine physical activity, sensitivity of walking stairs and lifting a heavy object versus head movements and bending down in terms of aggravating the headache was aimed to be determined. Eighty-one migraine patients were questioned about the aggravation of their headaches with two sets of question groups. (The first set: walking stairs and lifting a heavy object; The second set: rotating the head side to side and bending down). 38 and 72 patients gave clear answers to the first and second set of questions respectively. Clear information was obtained from the first and second group of questions by 38 and 72 patients respectively. Some patients with severe migraine headaches may prevent themselves from rigorous daily activities while they could bend or make sudden head movements inadvertently during the attack. We think that aggravation of the headache due to head movements or bending down during migraine attacks seems more sensitive than walking stairs or lifting a heavy object to migraine patients.
    European journal of medical research 06/2004; 9(5):279-81. · 1.10 Impact Factor
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    Marcus W Agelink, Ilker Kavuk, Ismail Ak
    American Journal of Psychiatry 06/2004; 161(5):924-5. · 14.72 Impact Factor
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    ABSTRACT: We reviewed the epidemiology of headache disorders for the most frequent primary headache-syndromes: migraine, tension-type headache and trigemino-autonomic headache syndromes. In the last years scientific data about headache disorders have increased. New studies investigated not only the prevalence of headaches, but also economic costs of this disorder. Epidemiologic headache research also investigates the quality of life.
    Fortschritte der Neurologie · Psychiatrie 05/2004; 72(4):184-91. · 0.85 Impact Factor
  • DMW - Deutsche Medizinische Wochenschrift 04/2004; 129(13):697-700. · 0.65 Impact Factor
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    ABSTRACT: Numerous studies provide evidence that major depression (MD) is associated with certain disorders of cardiac autonomic nervous system (ANS) function, in particular, with an autonomic neurocardiac imbalance characterized by a low cardiovagal modulation, a raised sympathetic nerve activity and a high resting heart rate. We assume that such MD-associated cardiac ANS disorders are mainly caused by functional-structural abnormalities within the central autonomic network (CAN), in particular, by well-defined abnormalities of hypothalamic structures in MD. In view of the well-known association between an autonomic neurocardiac imbalance and the risk for cardiac arrhythmias, we assume that MD-associated cardiac ANS disorders are at least partly responsible for the high cardiovascular mortality risk in MD. It is, however, still unclear whether antidepressive treatment will lower the risk for cardiovascular complications in MD. There is convincing evidence that a successful antidepressive treatment with electroconvulsive therapy, cognitive behavioral therapy, or pharmacotherapy with primarily non-antimuscarinergic antidepressants can improve an initially disturbed cardiac ANS function in MD. These studies correspond well to our findings that treatment with both, nefazodone or reboxetine, can induce a reduction of central sympathetic nerve activity and an increase of the initially lowered cardiovagal modulation depending on the improvement of depressive symptoms after treatment. Since both effects occured obviously independent from the primarily serotonergic or noradrenergic action of the antidepressants, our findings suggest the existence of a generally supraordinate and uniform mechanism underlying the ANS effects of antidepressive treatment with drugs inhibiting serotonin- or noradrenaline reuptake.
    European journal of medical research 02/2004; 9(1):37-50. · 1.10 Impact Factor
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    ABSTRACT: Hepatorenal syndrome (HRS) occurs in about 20 % of patients with liver cirrhosis and ascites and is characterized by intensive renal vasoconstriction, low glomerular filtration rate but preserved tubular function and normal renal histology. The potential of terlipressin and albumin to reverse HRS after a time period of 14 days has already been shown. However, intravenous albumin is expensive (approximately 25 per 50 ml 20% albumin in Germany) and has limited availability in some settings. Therefore we used an artificial plasma substitute, Gelatinepolysuccinat, which is less expensive (approximately 12 per 500 ml). The aim of our present study was to examine the effects of terlipressin and Gelatinepolysuccinat on renal function and hemodynamics in a time period of six days. Seven consecutive patients with cirrhosis and hepatorenal syndrome were included in a pilot study of terlipressin (6 mg /24 h iv) therapy associated with i.v. Gelatinepolysuccinat (Gelafundin 4% Infusionslösung, Company Braun, Mw: 30 000 D). In five of the seven patients treatment was associated with a marked reduction of serum creatinine after six days (3.85 +/- 0.44 mg/dl vs.1.9 +/- 0.32 mg/dl; p< 0.018). Creatinine clearance improved (20 +/- 8.8 ml/min vs. 43 +/- 11.7 ml/min; p<0.12). There was a remarkable improvement in circulatory function in all patients, with an increase in mean arterial pressure (58+/-4.4 mmHg vs. 75 +/- 4.5 mmHg, p< 0.001). No patient developed signs of intestinal, myocardial or distal ischemia. Terlipressin and Gelatinepolysuccinat appear to be a safe and effective treatment of hepatorenal syndrome.
    European journal of medical research 02/2004; 9(2):78-82. · 1.10 Impact Factor
  • M Solmaz, I Kavuk, K Sayar
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    ABSTRACT: The role of psychological factors in the irritable bowel syndrome (IBS) is a matter of debate. The prevalence of psychiatric disorders is high in IBS patients. Positive response to antidepressant therapy and presence of family history of depression in IBS patients have led speculations whether this syndrome might be regarded as an affective spectrum disorder. In this study we tried to examine the possible association of IBS with affective spectrum disorders. Forty IBS patients from gastroenterology outpatient clinics of a university hospital and state hospital, 32 controls with inflammatory bowel disease and 34 healthy hospital workers were included in the study. Psychiatric interviews were done using SCID-NP (Structured Clinical Interview for DSM-Non-patients) and psychological factors were assessed by the SCL-90-R (Symptom Checklist-90-Revised), the Beck Depression Inventory, the Beck Anxiety Scale and the Hamilton Rating Scale for Depression. Family histories were obtained by FH-RDC (Family History Research Diagnostic Criteria). All groups were matched for sociodemographic variables. The prevalence of psychiatric disorders and mood disorders was higher in the IBS group than the control groups. Also IBS group rated higher on anxiety and depression scales than the other groups, where the differences were statistically significant. Presence of positive family history for mood disorders was higher in the IBS group. These results support the hypothesis that IBS might be linked to affective spectrum disorder. Psychiatric assessment and therapy might be useful in the course of irritable bowel syndrome.
    European journal of medical research 01/2004; 8(12):549-56. · 1.10 Impact Factor
  • Psychoneuro. 01/2004; 30(10):541-547.
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    ABSTRACT: Wernicke's encephalopathy is a serious neurologic disorder caused by vitamin-B1 or thiamine deficiency. The classical triad of clinical symptoms described by Wernicke (gait ataxia, ophthalmoplegia, and confusion) are found in only a third of patients upon initial examination. Typical findings upon MR imaging in patients with Wernicke's encephalopathy are well documented, with signal intensities in the medial thalami and periaqueductal regions of the midbrain. We report a case of Wernicke's encephalopathy revealing an unusual contrast enhancement. It is therefore important to note that the acute stage of Wernicke's encephalopathy may be associated with an intense contrast enhancement upon MR-imaging reflecting the disruption of the blood-brain barrier and inflammatory processes caused by thiamine deficiency. As a consequence from the guideline for managing Wernicke's encephalopathy by the Royal College of Physicians early B-vitamin treatment in suspected is recommended cases.
    European journal of medical research 12/2003; 8(11):492-4. · 1.10 Impact Factor
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    ABSTRACT: The unique pathophysiology of end-stage liver disease (ESLD) has important implications on critical care treatment after liver transplantation. To determine hemodynamic parameters and responses, each patient must be carefully evaluated for the individual clinical appearance of cirrhosis and portal hypertension. Although data are limited, recent progress in the treatment of ESLD and its complications, such as hepatorenal syndrome (HRS), portopulmonary hypertension (PPH), and hepatopulmonary syndrome (HPS) is evident. The improved understanding of the pathophysiology of ESLD has resulted in novel treatments and approaches to the problems that emerge as patients get critically ill or undergo orthotopic liver transplantation (OLT). These issues become much more relevant with increased adult-to-adult living donor liver transplantation, where the scheduled operation allows a precise preoperative management in an Intensive Care Unit (ICU).
    European journal of medical research 12/2003; 8(11):511-6. · 1.10 Impact Factor

Publication Stats

311 Citations
46.31 Total Impact Points

Institutions

  • 2003–2006
    • University of Duisburg-Essen
      • Erwin L. Hahn Institute for Magnetic Resonance Imaging
      Essen, North Rhine-Westphalia, Germany
  • 2003–2004
    • University Hospital Essen
      • Klinik für Allgemeinchirurgie, Viszeral- und Transplantationschirurgie
      Essen, North Rhine-Westphalia, Germany