Background: Poststroke cricopharyngeal dysfunction has been reported to occur in 50% of brainstem strokes; however, cricopharyngeal dysfunction also occurs commonly in patients with supratentorial stroke. The hemispheric neuroanatomical location of this dysfunction has not been clearly identified. Aim: We aimed to analyze the relationship between cricopharyngeal dysfunction and supratentorial lesion location in poststroke patients through this retrospective case–control voxel-based lesion-symptom mapping study. Methods: Cricopharyngeal dysfunction was diagnosed when the residue after swallowing (pyriform sinus) accounted for more than 25% of volume of pyriform sinus. Medical records and the video fluoroscopic swallowing studies of first-ever stroke patients who were admitted to our hospital during acute to subacute phase from 2009 to 2019 were reviewed. After propensity score matching to reduce the likelihood of selection bias, 50 patients per group were included in the cricopharyngeal dysfunction and control groups. We used a P threshold of 0.01 corrected for multiple comparisons with permutation thresholding (5000 permutations). Dichotomized diagnosis of cricopharyngeal dysfunction and the magnitude of pyriform sinus were used as dependent variables. Results: Analysis using the Liebermeister statistics indicated that lesions of the right lentiform nucleus were associated with the development of cricopharyngeal dysfunction. After adjustment for age and total lesion volume, which are known effectors for the development of dysphagia, statistically significant correlations were found between pyriform sinus and lesions of the right lentiform nucleus and anterior corona radiata beneath the right middle frontal gyrus. Conclusion: Thus, our study demonstrated for the first time that damages to the right lentiform nucleus, especially globus pallidus externa, and anterior corona radiata beneath the right middle frontal gyrus are associated with the development and severity of cricopharyngeal dysfunction.

Aims: Dysphagia is a major clinical concern in Parkinson's disease (PD). However, the relationship between the development of phase‐specific dysphagia and the regional brain glucose metabolism remains unclear. Our objective was to investigate the distributions of brain glucose metabolism specific to oral and pharyngeal phases of dysphagia in PD.Methods: In this retrospective cross‐sectional study, patients with PD who underwent videofluoroscopic swallowing study (VFSS) and ¹⁸F‐fluorodeoxy‐glucose positron emission tomography at intervals of <1 month were included. Each swallow was assessed by the binarized Videofluoroscopic Dysphagia Scale with 14 subitems, seven each for the oral and pharyngeal phases. Metabolism mapping was performed by superimposing significant clusters of subitems belonging to each of the two phases using voxel‐wise Firth's penalized binary logistic regression model, adjusting for age and PD duration at VFSS.Results: Eighty‐two patients with PD who met the inclusion criteria were included in the analysis. The oral phase dysphagia‐specific overlap map showed hypermetabolism in the right inferior temporal gyrus, bilateral cerebellum, superior frontal gyrus, and anterior cingulate cortices. Hypometabolism in the bilateral orbital and triangular parts of the inferior to middle frontal gyrus was also correlated with the occurrence of oral phase dysphagia. The development of pharyngeal phase dysphagia was related to hypermetabolism of posterior aspects of the bilateral parietal lobes, cerebellum, and hypometabolism of the mediodorsal aspects of anterior cingulate and middle to superior frontal gyri.Conclusion: These findings suggest that phase‐specific distribution of brain glucose metabolism may explain the dysphagia of PD.

Purpose: To better understand the development of dysphagia in patients with Parkinson disease (PD) and to identify possible neuromodulatory target regions of dysphagia, we studied the striatal dopamine transporter (DAT) availability distribution by subtype of dysphagia. Methods: In this retrospective cross-sectional study, patients with PD who underwent videofluoroscopic swallowing study and N-(3-[¹⁸F]fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) nortropane (¹⁸F-FP-CIT) PET at intervals of less than 1 month were analyzed. The 14 binarized subitem scores of the Videofluoroscopic Dysphagia Scale were analyzed using a voxel-wise Firth’s penalized binary logistic regression model, adjusting for age and disease duration at videofluoroscopic swallowing study. Results: Sixty-five patients with PD were finally included. Striatal mapping showed association of decreased DAT availability with 5 subitems with 1 or more clusters surviving the statistical threshold: 1 oral phase and 4 pharyngeal phase subitems. The overlap maps created by superimposing clusters for all 5 statistically significant subitems revealed associations of dysphagia in PD with decreased DAT availability in the bilateral ventral striatum. Of these, 4 subitems belonging to the pharyngeal phase-specific dysphagia were additionally found to be related to dopaminergic degeneration of the bilateral anterior-to-posterior caudate and ventral striatum. Conclusions: These findings suggest that subitem/phase-specific striatal subregional dopaminergic depletion may explain the dysphagia of PD. This dopaminergic degeneration of striatal subregions specific to the phases of dysphagia may serve as a potential target for neuromodulatory brain stimulation through stimulation of cortices functionally connected.

Central post-stroke pain (CPSP) is an intractable neuropathic pain that can occur following central nervous system injuries. Spino-thalamo-cortical pathway damage contributes to CPSP development. However, brain regions involved in CPSP are unknown and previous studies were limited to supratentorial strokes with cortical lesion involvement. We analyzed the brain metabolism changes associated with CPSP following pontine hemorrhage. Thirty-two patients with isolated pontine hemorrhage were examined; 14 had CPSP, while 18 did not. Brain glucose metabolism was evaluated using ¹⁸F-fluorodeoxyglucose-positron emission tomography images. Additionally, regions revealing metabolic correlation with CPSP severity were analyzed. Patients with CPSP showed changes in the brain metabolism in the cerebral cortices and cerebellum. Compared with the control group, the CPSP group showed significant hypometabolism in the contralesional rostral anterior cingulum and ipsilesional primary motor cortex (P_uncorrected < 0.001). However, increased brain metabolism was observed in the ipsilesional cerebellum (VI) and contralesional cerebellum (lobule VIIB) (P_uncorrected < 0.001). Moreover, increased pain intensity correlated with decreased metabolism in the ipsilesional supplementary motor area and contralesional angular gyrus. This study emphasizes the role of the many different areas of the cortex that are involved in affective and cognitive processing in the development of CPSP.

Eosinophilic otitis media (EOM) is a rare middle ear disease with unfavorable outcomes. Under the current diagnostic criteria of EOM, it is challenging to suspect EOM before tympanostomy. Therefore, this study attempted to use blood eosinophil levels for the differential diagnosis of EOM from other conditions. Three disease groups with features of recurrent otorrhea were categorized, which included the following: EOM (n = 9), granulomatosis with polyangiitis (GPA, n = 12), and primary ciliary dyskinesia (PCD, n = 6). Clinical and radiological characteristics were analyzed in the three groups. Patients who underwent ventilation tube insertion due to serous otitis media were enrolled as the control group (n = 225) to evaluate the diagnostic validity of blood eosinophilia. The EOM group showed a significantly higher blood eosinophil concentration (p < 0.001) and blood eosinophil count (p < 0.001) compared to the GPA and PCD groups. The estimated sensitivity and specificity for diagnosing EOM from OME patients who underwent ventilation tube insertion were 100% and 95.6%, respectively. In addition, EOM tended to have protympanic space soft tissue density and a relatively clear retrotympanic space in temporal bone computerized tomography. Blood eosinophil evaluation is a significant clinical indicator of EOM. Furthermore, the assessment of exclusive protympanic soft tissue density can provide an additional diagnostic clue.

Background: Freezing of gait (FOG) is one of the most debilitating symptoms in patients with idiopathic Parkinson’s disease (IPD). Visual cues can relieve FOG symptoms. However, there is no consensus on patient characteristics that can benefit from visual cues. Therefore, we examined the differences in IPD patient characteristics according to the effectiveness of visual cueing. Methods: Through gait experiments, we investigated the number of FOG occurrences, average FOG period per episode, proportion of FOG duration in the total gait cycles, and FOG-free period gait spatiotemporal parameters in ten participants diagnosed with FOG due to IPD. Subsequently, the differences between their clinical characteristics and striatal dopamine active transporter availability from six subregions of the striatum were compared by dividing them into two groups based on the three reduction rates: occurrence numbers, mean durations per episode, and proportion of FOG duration in the total gait cycles improved by visual cueing using laser shoes. The relationships among these three reduction rates and other FOG-related parameters were also investigated using Spearman correlation analyses. Results: According to the three FOG-related reduction rates, the group assignments were the same, which was also related to the baseline self-reported FOG severity score (New Freezing of Gait Questionnaire): the more severe the FOG, the poorer the response to the visual cueing. By visual cueing, the better response group demonstrated the characteristics of lower new FOG questionnaire total scores, higher dopamine active transporter availability of the anterior and posterior putamen, and shorter mean duration of FOG per episode in the absence of cueing. These results were replicated using Spearman correlation analyses. Conclusions: For FOG symptoms following IPD, gait assistance by visual cueing may be more effective when the total NFOGQ score is lower and the DAT of putamen is higher. Through this study, we demonstrated clinical and striatal dopaminergic conditions to select patients who may be more likely to benefit from visual cueing with laser shoes, and these findings lead to the need for early diagnosis of FOG in patients with IPD. Trial registration: ClinicalTrials.gov identifier: NCT05080413. Registered on September 14, 2021.