Neuroanatomical Predictors of Dysphagia after Stroke: Voxel-Based Lesion Symptom Mapping Study / 대한연하장애학회지

OBJECTIVE: Dysphagia is a common consequence of stroke with a negative effect on the clinical outcome. Given these potential outcomes, it is important to identify the precursors to dysphagia after stroke. The aims of this study were to identify lesions associated with dysphagia after an ischemic supratentorial stroke using voxel-based lesion symptom mapping (VLSM) and compare the difference in the lesion pattern between the oral and pharyngeal phase dysphagia. METHODS: Stroke patients who met the following inclusion criteria were screened retrospectively between January 2012 and November 2014: a first-ever stroke, supratentorial lesion and who underwent brain MRI and functional dysphagia scale (FDS) from videofluoroscopic swallowing study (VFSS). Finally, the MRI data of 83 patients were analyzed. Statistical maps of the lesion contribution related to dysphagia were generated using VLSM. RESULTS: VLSM showed that FDS was associated with damage to the putamen, caudate, insula, frontal precentral gyrus, and inferior frontal gyrus. The lesions were distributed more widely in the left than right hemisphere. Lesions correlated with the FDS oral score were distributed mainly in the frontal lobe and insula. Otherwise, the associated lesion with the FDS pharyngeal score was mainly the basal ganglia. CONCLUSION: In these results, lesions that correlated with dysphagia were distributed more widely in the left hemisphere, reflecting the possibility of lateralization of the swallowing function. Oral phase dysphagia was associated with left frontal lobe and insula; the lesion correlated with the cognitive function or apraxia. On the other hand, VLSM revealed the lesions associated with pharyngeal dysphagia to be the basal ganglia, which is a structure that plays a role in the automatic motor control network.

Clinical Efficacy of Selective Focal Ablation by Navigable Percutaneous Disc Decompression Device in Patients With Cervical Herniated Nucleus Pulposus

OBJECTIVE: To evaluate the clinical efficacy and safety following percutaneous disc decompression, using navigable disc decompression device for cervical herniated nucleus pulposus (HNP). METHODS: Twenty subjects diagnosed with cervical HNP and refractory to conservative management were enrolled for the study. The herniated discs were decompressed under fluoroscopic guidance, using radiofrequency ablation device with navigable wand. The sagittal and axial plain magnetic resonance images of the clinically significant herniated disc, decided the space between the herniated base and outline as the target area for ablation. Clinical outcome was determined by Numeric Rating Scale (NRS), Neck Disability Index (NDI), and Bodily Pain scale of Short Form-36 (SF-36 BP), assessed after 48 weeks. After the procedure, we structurally matched the magnetic resonance imaging (MRI) and C-arm images through bony markers. The wand position was defined as being ‘correct’ if the tip was placed within the target area of both AP and lateral views; if not, the position was stated as ‘incorrect’. RESULTS: The average NRS fell from 7 to 1 at 48 weeks post procedure (p<0.05). In addition, statistically significant improvement was noted in the NDI and SF-36BP (p<0.05). The location of the wand tip resulted in 16 correct and 4 incorrect placements. Post-48 weeks, 3 of the incorrect tip cases and 1 correct tip case showed unsuccessful outcomes. CONCLUSION: The study demonstrated the promising results and safety of the procedure. Thus, focal plasma ablation of cervical HNP with navigable wand can be another effective treatment option.

Amusia After Right Temporoparietal Lobe Infarction: A Case Report

Which brain regions participate in musical processing remains controversial. During singing and listening a familiar song, it is necessary to retrieve information from the long-term memory. However, the precise mechanism involved in musical processing is unclear. Amusia is impaired perception, understanding, or production of music not attributable to disease of the peripheral auditory pathways or motor system. We report a case of a 36-year-old right-handed man who lost the ability to discriminate or reproduce rhythms after a right temporoparietal lobe infarction. We diagnosed him as an amusic patient using the online version of Montreal Battery of Evaluation of Amusia (MBEA). This case report suggests that amusia could appear after right temporoparietal lobe infarction. Further research is needed to elucidate the dynamic musical processing mechanism and its associated neural structures.

The Factors Associated With the Successful Outcomes of Percutaneous Disc Decompression in Patients With Lumbar Herniated Nucleus Pulposus

OBJECTIVE: To determine clinical and radiological factors that predict the successful outcome of percutaneous disc decompression (PDD) in patients with lumbar herniated nucleus pulposus (HNP). METHODS: We retrospectively reviewed the clinical and radiological features of patients who underwent lumbar PDD from April 2009 to March 2013. Sixty-nine patients with lumbar HNP were studied. Clinical outcome was assessed by the visual analogue scale (VAS) and the Oswestry Disability Index (ODI). Multivariate logistic regression analysis was performed to assess relationship among clinical and radiological factors and the successful outcome of the PDD. RESULTS: The VAS and the ODI decreased significantly at 1 year follow-up (p<0.01). One year after PDD, the reduction of the VAS (DeltaVAS) was significantly greater in the patients with pain for <6 months (p=0.03) and subarticular HNP (p=0.015). The reduction of the ODI (DeltaODI) was significantly greater in the patients with high intensity zone (p=0.04). Multivariate logistic regression analysis revealed the following 5 factors that were associated with the successful outcome after PDD: pain duration for <6 months (odds ratio [OR]=14.036; p=0.006), positive straight leg raising test (OR=8.425, p=0.014), the extruded HNP (OR=0.106, p=0.04), the sequestrated HNP (OR=0.037, p=0.026), and the subarticular HNP (OR=10.876, p=0.012). CONCLUSION: PDD provided significant improvement of pain and disability of patients. The results of the analysis indicated that the duration of pain <6 months, positive straight leg raising test, the subarticular HNP, and the protruded HNP were predicting factors associated with the successful response of PDD in patients with lumbar HNP.