Hyuk Chang

Correlation Between Insulin Resistance and Intracranial Atherosclerosis in Patients With Ischemic Stroke Without Diabetes

BACKGROUNDnInsulin resistance (IR) is associated with an increased risk for cardiovascular morbidity and mortality including ischemic stroke. Its final complications are cardiovascular and cerebrovascular disease caused by atherosclerosis. However, few studies on the relationship between IR and intracranial (IC) atherosclerosis have been reported.nnnMETHODSnWe analyzed 110 patients with acute stroke without diabetes who underwent brain magnetic resonance angiography and cerebral angiography. Patients were divided into 3 equal groups according to the tertiles of homeostasis model assessment of IR (HOMA-IR): group I (n = 36; HOMA-IR < 0.92), group II (n = 37; 0.92 <or= HOMA-IR < 1.55), and group III (n = 37; HOMA-IR >or= 1.55). Cerebral artery atherosclerosis was classified as either IC or extracranial (EC).nnnRESULTSnPatients with IC or EC atherosclerosis showed higher level of HOMA-IR than those without. When the association was assessed according to the site of atherosclerosis, HOMA-IR showed a significant association with the site of atherosclerosis (IC + EC > IC > EC, P < .01). Multivariate analysis revealed that HOMA-IR was an independent predictor of IC atherosclerosis.nnnCONCLUSIONSnAlthough the association between IR and stroke patterns in patients with atherosclerosis remains uncertain, IR is associated with IC atherosclerosis in patients with acute ischemic stroke without diabetes.

Tooth Loss May Predict Poor Cognitive Function in Community- Dwelling Adults without Dementia or Stroke: The PRESENT Project

Periodontal disease is a potential predictor of stroke and cognitive impairment. However, this association is unclear in adults aged 50 yr and above without a history of stroke or dementia. We evaluated the association between the number of teeth lost, indicating periodontal disease, and cognitive impairment in community-dwelling adults without any history of dementia or stroke. Dental examinations were performed on 438 adults older than 50 yr (315 females, mean age 63±7.8 yr; 123 males, mean age 61.5±8.5 yr) between January 2009 and December 2010. In the unadjusted analysis, odds ratios (OR) of cognitive impairment based on MMSE score were 2.46 (95% CI, 1.38-4.39) and 2.7 (95% CI, 1.57-4.64) for subjects who had lost 6-10 teeth and those who had lost more than 10 teeth, respectively, when compared with subjects who had lost 0-5 teeth. After adjusting for age, education level, hypertension, diabetes, hyperlipidemia, and smoking, the relationship remained significant (OR, 2.0; 95% CI, 1.08-3.69, P=0.027 for those with 6-10 teeth lost; OR, 2.26; 95% CI, 1.27-4.02, P=0.006 for those with more than 10 teeth lost). The number of teeth lost is correlated with cognitive impairment among community-dwelling adults aged 50 and above without any medical history of stroke or dementia.

Rathke’s pouch remnant and its regression process in the prenatal period

ObjectsDuring ontogeny, part of Rathke’s pouch, a physiologically superior pouching of the stomodeal ectoderm, may remain, forming the usual anomaly known as Rathke’s cleft cyst. More rarely, however, the entire pouch (i.e., the craniopharyngeal canal) remains, resulting in transsphenoidal meningoencephalocele. This study is aimed to provide a better understanding of the pathogenesis.Materials and methodsWe histologically evaluated the inferior protrusion of the putative hypophysial fossa in 35 embryonic and fetal heads, respectively (15 at 5–8xa0weeks and 20 at 12–16xa0weeks of gestation).ResultsIn 3 of the 35 specimens, we observed a complete cleft originating from the adenohypophysis, passing through the sphenoid and connecting with the pharyngeal epithelium or pharyngobasilar fascia. In another 18 specimens, we observed a duct-like structure protruding from the fossa and ending in the sphenoid. The sellar protrusion contained vein-like structures and debris of red blood cells. The protrusion was located on the anterior or anterosuperior side of the notochord. No ossification center was observed around the sellar region of the embryos. Although ossification occurred in 12 of the 20 fetuses, nine of the latter showed no evidence of cleft or protrusion, indicating that the incidence of Rathke’s pouch remnant was lower in the fetuses (11/20) than in the embryos (11/15).ConclusionRathke’s pouch may be closed by ossification of the sphenoid, but increased cell proliferation and/or large amounts of degenerated veins may provide a structure resistant to the mechanical pressure caused by ossification.

The Filum Terminale Revisited: A Histological Study in Human Fetuses

Previous studies have suggested that secondary neurulation provides no functional neurons but only the filum terminale. However, no studies have confirmed that the coccygeal and lower sacral nerves do not originate from the secondary neural tube but only from the primary tube. To obtain a better understanding of these relationships, we examined sagittal or frontal sections from 20 embryonic and fetal specimens ranging from 6 to 14 weeks of gestation. During the growth of the vertebral column as well as the subsequent upward migration of the caudal end of the dural sac, the secondary neural tube was stretched to maintain the original attachment to the coccyx or the lower sacral vertebra. The filum-like structure showed much individual variability but in all cases appeared to be derived from the stretched neural tube. Intermediate age morphology revealed that the secondary neural tube itself provided an initial filum terminale before the ascent of the dural sac. Given that the coccygeal and lower sacral nerves are likely to originate from the secondary neural tube, these parts of the tube persisted and differentiated into spinal neurons to form the anococcygeal nerves. Likewise, the filum terminale was also most likely to contain some neurons that persisted postnatally. Depending on the timing and site of degeneration of the secondary neural tube, individual variations could occur in proportion to the amount of sensory and motor elements in the anococcygeal nerve supply.

Site- and stage-dependent differences in vascular density of the human fetal brain

Background and purposeLess information is available about site-dependent differences in fetal intrabrain angiogenesis. Quantitative evaluation is especially limited, with the measured area limited to the cerebral gray and white matters and the periventricular germinal matrix.Patients and methodsWe measured vascular density (number of vessels per square millimeter) and percent vascular area (percentage of areas occupied by vessels) of CD34-positive microvessels in 14 human fetal brains, including 4 fetuses at 14–16xa0weeks of gestation, 5 at 25–28xa0weeks, and 5 at 35–37xa0weeks. Site-dependent differences were examined among the cerebral cortex, thalamus, internal capsule, corpus callosum, ganglionic eminence, midbrain, and cerebellar cortex and nuclei.ResultsThe parameters examined tended to be high in the cerebral germinal matrix, thalamus, midbrain, and cerebellum. Significant site-dependent differences were observed: lower vascular densities were observed in the internal capsule and corpus callosum than in other parts of the brain (pu2009<u20090.05) and a larger percent area was observed in the cerebellar nuclei than in other areas. Vascular density was higher during the early than late stage because of the larger numbers of CD34-positive islands of cells in the early stage, although there were several exceptions. Percent area was not stage dependent but was almost constant at many sites.ConclusionConsequently, except for developing nuclei, the prenatal development of intrabrain vessels after 15xa0weeks may proceed without any significant changes in density.

Association between insulin resistance and cognitive function in mild cognitive impairment

with CDRS score 0.5, who did not meet the DSM-IV dementia criteria, were selected and diagnosed as MCI. 38 subjects with CDRS score 0.5 or more, who met the DSM-IV dementia criteria were diagnosed as AD. Old age, low levels of education, histroy of head trauma were associated significantly with AD (p<0.01, p<0.01 p<0.05). Interestingly, the proportion of subjects on DM medications was significantly different among the three groups (p<0.05). There were significant differences in the mean score of MMSE-KC and GDS-K among normal, MCI and the AD group (p<0.01, p<0.01). These scores were significantly correlated with each other in this study population (p<0.05). There was a significant correlation between the MMSE-KC score and serum total cholesterol and triglyceride levels in MCI group (p<0.05, p<0.05), but not in normal controls and AD group. Finally, we found that the mean score of Hachinski Ischemic Scale was significantly different among three groups (p<0.05). Conclusions: Our results strongly suggested that many vascular risk factors are associated with cognitive impairments in MCI and AD patients. In this study,serum lipid levels were associated with global cognitive dysfunction in MCI group. We confirmed that DM is a risk factor for MCI and AD in our Korean population.

Status of treatment for dementia patients who visited hospital as the first visit

We are approaching a period of population ageing in which the number of dementia patients will increase rapidly and become a significant social problem. There are many study guides for treatment of dementia, but there are limited numbers of studies and limited amounts of data available for evaluating the treatment used on dementia patients as related to their hospital for the first time. A study was performed using information gathered from 50 domestic hospitals to ensure that the treatment status data was representative of the actual field of clinical dementia. We observed retrospectively the medical records of 4282 patients who visited the hospital and were finally judged to have dementia from January, 2009 to December, 2010. Among the types of dementia, Alzheimers disease (AD) had the greatest occurrence at 66.57%, with vascular dementia (VD) at 17.63%, AD with CVD at 10.18%, and Parkinson related dementia at 4.25%. The drug primarily used for initial therapy is the same drug primarily used for patients who have undergone long term dementia treatment, namely donepezil (75.22%). Among all 4282 patients, there was addition or transition of drugs used for 389 of the patients. Ineffectiveness of the initial drug treatment was the reason for the addition of drugs or transition to other drugs in almost all cases. In this study, the clinical characteristics observed for dementia treatment is compared as drugs changing, which will be helpful in the preparation of a treatment guide for dementia in the future.

To do or not to do; dilemma of intra-arterial revascularization in acute ischemic stroke.

Background There has still been lack of evidence for definite imaging criteria of intra-arterial revascularization (IAR). Therefore, IAR selection is left largely to individual clinicians. In this study, we sought to investigate the overall agreement of IAR selection among different stroke clinicians and factors associated with good agreement of IAR selection. Methods From the prospectively registered data base of a tertiary hospital, we identified consecutive patients with acute ischemic stroke. IAR selection based on the provided magnetic resonance imaging (MRI) results and clinical information were independently performed by 5 independent stroke physicians currently working at 4 different university hospitals. MRI results were also reviewed by 2 independent experienced neurologists blinded to clinical data and physicians IAR selection. The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) was calculated on initial DWI and MTT. We arbitrarily used ASPECTS differences between DWI and MTT (D-M ASPECTS) to quantitatively evaluate mismatch. Results The overall interobserver agreement of IAR selection was fair (kappau200a=u200a0.398). In patients with DWI-ASPECTS >6, interobserver agreement was moderate to substantial (0.398–0.620). In patients with D-M ASPECTS >4, interobserver agreement was moderate to almost perfect (0.532–1.000). Patients with higher DWI or D-M ASPECTS had better agreement of IAR selection. Conclusion Our study showed that DWI-ASPSECTS >6 and D-M ASPECTS >4 had moderate to substantial agreement of IAR selection among different stroke physicians. However, there is still poor agreement as to whether IAR should not be performed in patients with lower DWI and D-M ASPECTS.

Multifocal strokes as the initial manifestation of metastatic tumors.

Patients with cancer are hypercoagulable and at a significant risk for ischemic stroke, but rarely present with stroke as the first manifestation of an underlying malignancy. We report on 2 patients with bihemispheric, multiterritorial infarctions in the absence of a cardioembolic source.

White matter lesions in Creutzfeldt-Jakob disease

We evaluated the correlation between each fractional anisotrophy (FA) and depression scores. Methods: Nineteen SIVD patients underwent DTI. Total 30 ROIs were measured. We conducted the correlation analysis between the depression scores FA in each 30 ROI. Results: In SIVD patients, there is a tendency of lower values of FA in the posterior body of the corpus callosum as the depression scores are getting higher.(r 1⁄4 -0.462, p < 0.05) On the other hand, there is a tendency of higher values of FA in the left temporal white matter region as the depression scores are getting higher.(r 1⁄4 0.456, p < 0.05) Conclusions: Lower FA of posterior body of the corpus callosum might imply underlying structural abnormalities that contribute to the depressive mood in SIVD patients. Higher FA of left temporal region might cause depressive mood. However, the exact mechanism how the higher left temporal FA correlates with depressive mood is not elucidated. Further large scale study should be followed to determine the roles of altered FA values in the corpus callosum and left temporal area in the pathogenesis of depression mood.