Sağlıklı Bireylerde ve Kognitif Etkilenmesi Olanlarda Kokusal ve Görsel Elektrofizyolojik İncelemelerin Tanıya Katkısı ve Nöropsikolojik Test Sonuçlarıyla İlişkisi

Çalışmamıza unutkanlık yakınması tanımlayan ya da bu yakınma ile getirilen 45 olgu ile yakınması olmayan ve nörolojik muayeneleri normal bulunan 39 olgu alınmış ve olguların tümünde GATA Haydarpaşa Eğitim Hastanesi Nöroloji Servisi Nöropsikolojik Test Bataryası, Koku Tarama Testi, Normal ve Koku ile aktive edilmiş EEG, Görsel Uyandırılmış Yanıtlar ile Olaya İlişkin Potansiyel incelemeleri gerçekleştirilmiştir. Koku Tarama Testinde normal olgularda ortalama koku skoru 8 ve alt sınırı 5 olarak bulunmuş, koku skorları ile yaş ve nöropsikolojik incelemeler arasında anlamlı ilişki saptanmıştır. Koku skorlarının hasta grupları ile karşılaştırılmalarında elde edilen sonuçlar anlamlı bulunmuştur. EEG incelemelerinde gerek normal gerekse hasta gruplarında özgün anormallikler saptanmamış ve çoğunluğunda normal EEG bulguları saptanmıştır. Ancak koku uyaranı ile birlikte anormal EEG oranlarında artma izlenmiş ve artış özellikle kötü koku uyarımında belirginleşmiştir. Görsel Uyandırılmış Yanıt Çalışması binoküler olarak gerçekleştirilmiş ve normal olgular ile hastalarda saptanan belirgin anormallik P100 genliğinde düşme olmuştur. P100 genliği ile koku skorları ve yaş arasında normal olgularda anlamlı ilişki saptanmış, hastalarda ise bu ilişki saptanmamıştır. Olaya İlişkin Potansiyel incelemelerinde normal inceleme sonrası ayrıca kokusal uyaran uygulanmış ve belirgin anormallik olarak normal olgularla kıyaslandığında P3 genliğinde düşme, Alzheimer Hastalığı grubunda ise P3 latansında uzama saptanmıştır. Özellikle kötü koku uyaranında benzer bulguların belirginleştiği gözlenmiştir. Çalışma sonucunda klinik ve elektrofizyolojik olarak kognitif bozuklukların değerlendirilmesinde yaptığımız testlerin geliştirilerek uygulanmasının yararlı olacağı kanısı oluşmuştur.

Anahtar Kelimeler:

Kognitif Etkilenme, Koku Tanıma, Olaya İlişkin Potansiyeller

The Contribution of Olfactive and Visual Electrophysiological Tests to Diagnosis in Healthy and Cognitively Affected Individuals and its Relation to Nerophyschological Test Results

This study includes 45 patients with memory complaints and 39 normal subjects. All participants were examined with neuropsychological test battery, smell identification test, EEG, olfactor evoked EEG, visual evoked responses and event related potential studies. Mean score in smell identification test was 8 and cut off score was 5. There was significant relation between smell scores and neuropsychological test scores. Significant results were found in the patient group. In EEG examination, spesific abormalities were detected neither in normal nor patient groups and majority of the EEGs were normal. However smell stimulation increased the rate of abnormal EEG findings where the noxius smells especially increased the abnormality rate. Visual evoked response study performed as binocular and major abnormality between the patients and normal subjects was decrease in the P100 amplitudes. In the normal subjects, there were significant relationships between the amplitude of the P100 waves and smell scores and age although it was not observed in the patient group. In the event related potential studies olfactor stimulation was performed after routine examination and main abnormality was found as decrease in the P3 amplitude in the patient groups. In the Alzheimer patients group there was increase in the latency of P3 wave. Noxius smells strengthened these findings. As a conclusion in the evaluation of the cognitive disorders such procedures may be useful and may provide additional information.

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