Postoperative neurological dysfunction due to the surgical procedure is a serious problem. It directly impacts the patient’s activities of daily living. Intraoperative neuro-monitoring has an important role in prevention. For more reliable neuro-monitoring, it is necessary for surgeons, anesthesiologists, and surgical technicians involved in surgery to share information and knowledge during surgery. In 2015, our monitoring team introduced a preoperative checklist for sharing information during neuro-monitoring. We believe that this checklist facilitates more reliable and accurate neuro-monitoring. Furthermore, we made a new corresponding checklist and clinical algorithms after deterioration of intraoperative waveforms is detected. The purpose of this study was to review our clinical series retrospectively and clarify the usefulness of our checklist and clinical algorithms. We found that the percentage of false positive findings decreased from 12.06% to 0.94% after introduction of the checklists.
Schizophrenia has been associated with the dysfunction of prefrontal cortex, which is involved in executive function and working memory. Near-infrared spectroscopy (NIRS) is a novel diffuse optical neuromonitoring method with its own advantages and limitations. In this study, we compared the characteristics of oxygenated hemoglobin concentration changes (Δoxy-Hb) involved in both phonological and categorical verbal production between 40 outpatients with schizophrenia and 40 healthy subjects during a Japanese “shiritori” task using NIRS by Kurume Single Event Related Design (K-SERD). In this task, one session consisted of two contrasting conditions (word production task, control condition), and all subjects alternated between these conditions. Each word was visually presented by a monitor for 0.3 seconds as an activation task and a fixed circle was presented for 12 seconds. In the activation task, subjects had to immediately generate a noun that starts with the last syllable of the presented word and they were required to say only creatures. From the data obtained at each measurement point during the 20 trials, and averaged waveform during activation task (20 trials) was calculated for each channel. During this task, the schizophrenic patients showed significantly smaller activation than the controls in the prefrontal cortex area and inferior parietal area. In addition, there was a significant negative correlation between Δoxy-Hb in the patients with schizophrenia and general psyhopathology score (in left midfrontal area) of PANSS. These findings suggest that NIRS measurement during Japanese shiritori tasks by K-SERD may be useful tool for evaluating psychophysiological indices in patients with schizophrenia, that relationship between activation and general psyhopathology score may be of help in predicting functional outcome in patients.
Measurements of brain function provide important information in psychiatry. In particular, electroencephalography (EEG) is a tool with excellent temporal resolution and can detect neural activity with a millisecond resolution. The spatial resolution of EEG, however, which is a limitation, can be improved by adding mapping methods such as LORETA (low-resolution electromagnetic tomography), which we have applied to pharmacological and other studies for schizophrenia spectrum disorders. First, we evaluated the P300, a type of ERPs (event-related potentials) in patients with schizophrenia before and after treatment with olanzapine. A significant increase in the LORETA value was found at the superior temporal gyrus. This increase was correlated with an enhancement of verbal memory and an improvement of negative symptoms. Second, we performed a similar study with perospirone instead of olanzapine. Perospirone caused an increase in the LORETA value at the left superior frontal gyrus. Third, we administered perospirone to an ARMS (at-risk mental state) patient. We found cognitive improvement as measured by neuropsychological performance. Enhancement of P300 amplitudes at Fz and Cz was also found and it was preceding the neuropsychological improvement following the perospirone treatment. In sum, these studies revealed the usefulness of ERPs and its brain imaging of electrophysiological measures in pharmacotherapy of schizophrenia.