Pulvinar quantitative susceptibility mapping predicts visual hallucinations post-deep brain stimulation in Parkinson's disease.

PURPOSE: We have reported the relationship between low pulvinar nuclei (PN) intensity in susceptibility-weighted imaging and the appearance of visual hallucinations and cognitive function. The aim of the study was to examine the changes in the quantitative susceptibility mapping (QSM) in patients with Parkinson's disease (PD) who underwent deep brain stimulation (DBS) and verify whether the PN susceptibility value (SV) on QSM can predict visual hallucination and cognitive changes after DBS. METHODS: This study examined 24 patients with PD who underwent DBS along with QSM imaging on magnetic resonance imaging (MRI). All MRIs were performed within 3 months before surgery. The PN SV was further assessed based on the QSM. Then, associations were examined among cognitive changes, hallucination, and PN SV. The cognitive function of the patient was compared immediately before surgery and at 1 year postoperatively. RESULTS: Visual hallucinations were observed in seven patients during the follow-up period. The PN SV was ≥0.045 ppm in nine patients with PD, and six of them had visual hallucinations, whereas only one of 15 patients with PD with SV of <0.045 ppm had visual hallucinations (Fisher's exact test, p = .0037). CONCLUSIONS: The SV of >0.045 ppm at the PN in QSM in patients with PD may provide useful information suggesting visual hallucination and cognitive deterioration after DBS treatment.

Sporadic Myotonic Dystrophy Type 2 in a Japanese Patient.

We herein report a Japanese patient with myotonic dystrophy type 2 (DM2), which is rare in Japan. A 64-year-oldman had proximal muscle weakness and grip myotonia. Electromyography showed myotonic discharges, but dystrophia-myotonica protein kinase (DMPK) was negative for CTG repeats. A muscle biopsy revealed increased central nuclei, pyknotic nuclear clumps and muscle fiber atrophy, mainly in type 2 fibers, raising the possibility of DM2. The diagnosis was genetically confirmed by the abnormal CCTG repeat size in cellular nucleic acid-binding protein (CNBP) on repeat-primed polymerase chain reaction, which was estimated to be around 4,500 repeats by Southern blotting.

Cerebral Embolism Associated with Calcified Amorphous Tumor: A Review of Cerebral Infarction Cases.

Calcified amorphous tumor (CAT) is a non-neoplastic tumor composed of calcified nodules consisting of amorphous fibrous material, and it may eventually cause cerebral infarction (CI). We experienced a 67-year-old woman with CAT who had recurrent CI. After excision of the CAT, the CI did not show recurrence. A review of previous papers on CI due to CAT in Pubmed revealed that 7 of 13 studies originated in Japan and that CI can occur even with small CAT. Surgical treatment is recommended to prevent CI recurrence, especially when CAT is accompanied by mitral annular calcification or has marked mobility.

A Case of Miyazaki Syndrome Caused by Arachnoid Cyst-Peritoneal Shunt.

BACKGROUND: Miyazaki syndrome is overshunting-associated myelopathy, which is a rare complication of ventriculoperitoneal shunt. We present the first case of Miyazaki syndrome caused by cystoperitoneal (CP) shunt for an arachnoid cyst (AC) in this report. CASE DESCRIPTION: We report a case of a 42-year-old man with 12-year progressive spastic paraplegia, who underwent CP shunt for an AC at the age of 15 years. Although few findings suggested overshunting on symptoms and head computed tomography, contrast-enhanced magnetic resonance imaging revealed the engorgement of the cervical spinal epidural venous plexus compressing the spinal cord. Shunt valve replacement with a pressure-adjustable valve was performed. Postoperatively, the cervical cord compression by the enlarged spinal epidural venous plexus was completely improved, but, possibly due to delayed diagnosis and treatment, the patient's symptoms only partially improved. CONCLUSIONS: When patients with a history of any kind of shunt surgery develop myelopathy, Miyazaki syndrome should be suspected and, for early diagnosis, cervical and/or contrast-enhanced magnetic resonance imaging should be performed.

Myasthenia gravis with anti-muscle-specific tyrosine kinase antibodies during therapy for multiple myeloma: a case report.

BACKGROUND: The onset of myasthenia (MG) gravis with anti-muscle-specific tyrosine kinase (MuSK) antibodies most commonly peaks in the fourth decade of life, and MG with MuSK antibodies (MuSK-MG) rarely coexists with a malignant tumor. To date, MuSK-MG has not been reported in multiple myeloma (MM). CASE PRESENTATION: A 60-year-old male with MM who was receiving treatment with bortezomib and thalidomide presented diplopia, ptosis, and limb weakness. A diagnosis of MM with Bence-Jones proteinuria was established when he was 56 years old, and he received chemotherapy with four courses of bortezomib and dexamethasone. Although he received thalidomide as maintenance therapy, it was discontinued a year before hospital admission because of sensory neuropathy as a side effect. Six months before hospital admission, he developed mild diplopia. One month before admission, his chemotherapy was interrupted because of viral infection and fatigability. Then he developed neck weakness and bilateral ptosis. A diagnosis of MuSK-MG was made based on neurological and serological examinations. According to the previous relevant literature, this is the first report of MuSK-MG in a patient with MM. CONCLUSIONS: In patients with MM, the possibility of co-existing of autoimmune disease, including MuSK-MG, should be considered. This case emphasizes the need to still consider testing for anti-MuSK antibodies in older MM patients where there is clinical suspicion for possible MG despite negative anti-acetylcholine receptor antibodies and lacking classic MuSK MG phenotype at onset.

Chronic cerebral hypoperfusion activates AIM2 and NLRP3 inflammasome.

Inflammation plays an important role in acute and chronic cerebral ischemia. Recent reports indicate that the inflammatory response triggered by tissue damage is mediated by a multiple-protein complex called the inflammasome. The NOD-like receptor family, pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasome complex triggers caspase 1-mediated maturation of interleukin (IL)-1ß and IL-18. This study tested the hypothesis that chronic cerebral hypoperfusion activates inflammasomes in the white matter of the brain. To induce cerebral hypoperfusion, C57BL/6J mice were subjected to a sham or bilateral common carotid artery stenosis (BCAS) operation using microcoils with an internal diameter of 0.18 mm. At 2 and 4 weeks after BCAS, the mice were sacrificed (n = 5 in each group). Coronal sections were stained with anti-NLRP3 and anti-AIM2 antibodies. Activation of the inflammasome and cytokines was assessed using immunohistochemistry and cell counting. IL-18 and IL-1ß levels were determined by ELISA. Cell counting revealed an increase in NLRP3 and AIM2 inflammasomes at 2 and 4 weeks after BCAS. Immunoreactivity was observed in glial cells in the white matter and corpus callosum. IL-18 and IL-1ß concentrations were significantly increased compared with those in the sham operation group. Expression of NLRP3 and AIM2 was upregulated in glial cells in the autopsied brains of patients with cerebral infarction in the chronic phase. These results suggest that chronic cerebral hypoperfusion induces upregulation of NLRP3 and AIM2 inflammasomes; therefore, inflammasomes may play an important role in the sterile inflammatory response in astrocytes and microglia during chronic cerebral hypoperfusion.

Chronic cerebral hypoperfusion upregulates leptin receptor expression in astrocytes and tau phosphorylation in tau transgenic mice.

Alzheimer's disease (AD) is the most common type of dementia in aging adults. Increasing evidence has revealed that vascular risk factors influence the midlife development of AD and that diet-induced obesity accelerates tau phosphorylation in tau transgenic mice and increases the level of serum leptin receptor (leptin-R). Leptin-R is upregulated in the peri-infarct cortices after acute cerebral ischemia. Leptin may be protective against the development of AD as it can inactivate GSK-3ß through the phosphorylation of Ser-9, leading to the reduction of tau phosphorylation. Using tau transgenic mice, the present study examined whether chronic cerebral hypoperfusion affects leptin-R signaling and tau phosphorylation. Eight-month-old tau transgenic mice (T44) overexpressing the shortest human tau isoform were subjected to chronic cerebral hypoperfusion with bilateral common carotid artery stenosis (BCAS) using microcoils or sham surgery. Their brains were analyzed four weeks later to evaluate the expression of phosphorylated tau and leptin-R via immunohistochemistry and Western blot analysis. In addition, expression of leptin-R was examined in the rat primary astrocyte cultures subjected to prolonged chemical hypoxic stress, as well as in autopsied brains. BCAS upregulated leptin-R expression and promoted the expression of phosphorylated tau in T44 Tg mice. In primary astrocyte cultures, leptin-R was upregulated under hypoxic conditions via the phosphorylated AKT/pAKT pathway, possibly suppressing the expression of caspase 3. Leptin-R was also strongly expressed in autopsied brains with AD and cerebrovascular diseases. These results collectively indicate that chronic cerebral hypoperfusion promotes leptin-R signaling and tau phosphorylation.

Background and distribution of lobar microbleeds in cognitive dysfunction.

Objectives: Cerebral microbleeds (CMBs) are often observed in memory clinic patients. It has been generally accepted that deep CMBs (D-CMBs) result from hypertensive vasculopathy (HV), whereas strictly lobar CMBs (SL-CMBs) result from cerebral amyloid angiopathy (CAA) which frequently coexists with Alzheimer's disease (AD). Mixed CMBs (M-CMBs) have been partially attributed to HV and also partially attributed to CAA. The aim of this study was to elucidate the differences between SL-CMBs and M-CMBs in terms of clinical features and regional distribution. Materials: We examined 176 sequential patients in our memory clinic for clinical features and CMB location using susceptibility-weighted images obtained on a 3T-MRI. The number of lobar CMBs in SL-CMBs and M-CMBs was counted in each cerebral lobe and their regional density was adjusted according to the volume of each lobe. Results: Of the total 176 patients, 111 patients (63.1%) had CMBs. Within the patients who had CMBs, M-CMBs were found in 54 patients (48.6%), followed by SL-CMBs in 35 (31.5%) and D-CMBs in 19 (17.1%). The SL-CMB group showed a significantly higher prevalence of family history of dementia, whereas the M-CMB group showed an increasing trend toward hypertension and smoking. The prevalence of AD was significantly higher in the SL-CMBs group, whereas the prevalence of AD with cerebrovascular disease was higher in the M-CMBs group. The regional density of lobar CMBs was significantly higher in the occipital lobe in the M-CMB group, whereas the SL-CMB group showed higher regional density between regions an increasing tendency in the parietal and occipital lobe. Conclusion: The between-group differences in clinical features and regional distribution indicate there to be an etiological relationship of SL-CMBs to AD and CAA, and M-CMBs to both HV and CAA.

A case of follicular lymphoma associated with paraneoplastic cerebellar degeneration.

Paraneoplastic neurological disorders (PND) are neurological effects of malignancy that are recognized as immune-mediated disorders caused by aberrant expression of a tumor antigen that is normally expressed in the nervous system. We report a case of cerebellar ataxia which turned out to be paraneoplastic cerebellar degeneration, a subtype of PND that develops cerebellar symptoms, that was caused by follicular lymphoma. After chemotherapy, the patient attained sufficient improvement of cerebellar symptoms along with complete remission of lymphoma. Paraneoplastic cerebellar degeneration should be recognized as a rare complication of lymphoma as it is important to start proper treatment before the neurological symptoms become irreversible.