Masahiro Kameda

Background: Falls along with gait‐balance disturbances are important symptoms of idiopathic normal pressure hydrocephalus (iNPH).Objectives: This study aimed to validate the Functional Gait Assessment (FGA) item‐difficulty hierarchy, determine its optimal fall cutoff value, and identify key items for assessing fall risk in iNPH.Methods: One hundred eighty‐eight iNPH patients underwent pre‐intervention assessments using the FGA, timed up‐and‐go (TUG), 10‐Meter Gait Speed (10MGS) tests, and their falls history in the past 6 months. Rasch analysis confirmed the validity of the FGA item‐difficulty hierarchy and established the relationship between total scores and logit estimates. Logistic regression identified the optimal FGA cutoff value and key fall‐related items.Results: The FGA's item‐difficulty hierarchy was confirmed to range from item 5 (“gait and pivot turn”) at −2.58 logits (easiest) to item 7 (“gait with narrow base of support”) at 5.35 logits (most difficult). Total scores corresponded to logits from −10.39 (score 0) to 11.64 (score 30). The fall rate was 63.3%. The optimal FGA cutoff value was ≤15 points (area under curve [AUC]: 0.901, P < 0.001), outperforming TUG (AUC: 0.712) and 10MGS (AUC: 0.742). Key fall‐related items (R²: 0.545, P < 0.001) were item 2 (“change in gait speed”), item 7 (“gait with narrow base of support”), item 1 (“gait on level surface”), item 10 (“stair steps”), and item 5 (“gait and pivot turn”).Conclusions: Our findings may facilitate early diagnosis and timely interventions, including tailored rehabilitation and fall prevention strategies, by leveraging the item difficulty and characteristics of the FGA for iNPH patients.

We report the case of a 70‐year‐old woman with metastatic brain tumors who underwent surgical removal of the tumor and radiation necrosis. The patient had a history of colon cancer and had undergone surgical removal of a left occipital tumor. Histopathological evaluation revealed a metastatic brain tumor. The tumor recurred six months after surgical removal, followed by whole‐brain radiotherapy, and the patient underwent stereotactic radiosurgery. Six months later, the perifocal edema had increased, and the patient became symptomatic. The diagnosis was radiation necrosis and corticosteroids were initially effective. However, radiation necrosis became uncontrollable, and the patient underwent removal of necrotic tissue two years after stereotactic radiosurgery. Pathological findings predominantly showed necrotic tissue with some tumor cells. Since the vascular endothelial growth factor (VEGF) and hypoxia‐inducible factor‐1α (HIF‐1α) were expressed around the necrotic tissue, the main cause of the edema was determined as radiation necrosis. Differences in the expression levels and distribution of HIF‐1α and VEGF were observed between treatment‐naïve and recurrent tumor tissue and radiation necrosis. This difference suggests the possibility of different mechanisms for edema formation due to the tumor itself and radiation necrosis. Although distinguishing radiation necrosis from recurrent tumors using MRI remains challenging, the pathophysiological mechanism of perifocal edema might be crucial for differentiating radiation necrosis from recurrent tumors.

New therapeutic hypothesis for infantile extrinsic hydrocephalus

Corrigendum: Evaluation of the Effectiveness of the Tap Test by Combining the Use of Functional Gait Assessment and Global Rating of Change