ABSTRACT
BACKGROUND: Alzheimer's disease is a chronic neurodegenerative condition, mostly affecting the medial temporal lobe and associated neocortical structures. In this report, we present a rare clinical manifestation of this disease. CASE REPORT: A 61-year-old female with word finding difficulty and memory disturbances was diagnosed with Alzheimer's disease. Two years later, she complained of right homonymous hemianopia without optic ataxia, ocular apraxia, and simultagnosia. No findings other than parenchymal disease were apparent in magnetic resonance imaging and laboratory tests. CONCLUSIONS: In this case, in a patient initially diagnosed with Alzheimer's dementia with progressive disease, we found only homonymous hemianopia, without signs of Balint's syndrome or Gerstmann's syndrome. After careful investigation showing that Alzheimer's dementia with visual symptom was not associated with parenchymal disease, we concluded a case of atypical variant of Alzheimer's disease.
ABSTRACT
Essential tremor is an involuntary trembling of body limbs in people without tremor-related disease. In previous study, suppression of tremor by sensory electrical stimulation was confirmed on the index finger. This study investigates the effect of sensory stimulation on multiple segments and joints of the upper limb. It denotes the observation regarding the effect's continuity after halting the stimulation. 18 patients with essential tremor (8 men and 10 women) participated in this study. The task, "arms stretched forward", was performed and sensory electrical stimulation was applied on four muscles of the upper limb (Flexor Carpi Radialis, Extensor Carpi Radialis, Biceps Brachii, and Triceps Brachii) for 15 seconds. Three 3-D gyro sensors were used to measure the angular velocities of segments (finger, hand, and forearm) and joints (metacarpophalangeal and wrist joints) for three phases of pre-stimulation (Pre), during-stimulation (On), and 5 minute post-stimulation (P5). Three characteristic variables of root-mean-squared angular velocity, peak power, and peak power frequency were derived from the vector sum of the sensor signals. At On phase, RMS velocity was reduced from Pre in all segments and joints while peak power was reduced from Pre in all segments and joints except for forearm segment. Sensory stimulation showed no effect on peak power frequency. All variables at P5 were similar to those at On at all segments and joints. The decrease of peak power of the index finger was noted by 90% during stimulation from that of On phase, which was maintained even after 5 min. The results indicate that sensory stimulation may be an effective clinical method to treat the essential tremor.