Associations between Nocturnal Hypoxemia and Retinal Nerve Fiber Layer Thinning: The Nagahama Study

Rationale: There have been meta-analyses that showed reduced retinal nerve fiber layer (RNFL) thickness, which is a surrogate marker of glaucoma, in patients with obstructive sleep apnea (OSA). However, the sample sizes in these reports were small (<300), and the mechanism of RNFL thinning in patients with OSA was not revealed.Objectives: To investigate the relationship of RNFL thickness with nocturnal hypoxemia or hypoxemic burden in a large-scale study.Methods: In this epidemiological study, 8,309 community residents were enrolled. The actigraphy-modified 3% oxygen desaturation index (acti-ODI3%) and cumulative percentage of sleep time with oxygen saturation <90% (acti-CT90) modified by objective sleep duration using actigraphy were measured. The hypoxemic burden is shown as acti-CT90. Circumpapillary RNFL thickness was determined using optical coherence tomography.Results: Multivariable logistic analysis models revealed that an increase in acti-CT90 was significantly associated with mean RNFL thinning after adjusting for several factors in participants without glaucoma diagnosed or treated previously (β = -0.037; P = 0.009). There were significant differences in mean RNFL thickness among participants stratified according to acti-CT90 (>1.5 vs. ⩽1.5; P = 0.04). Although acti-ODI3% was significantly associated with acti-CT90 (β = 0.72; P < 0.0001), acti-ODI3% was not significantly associated with mean RNFL thickness in the multivariable logistic analysis (β = -0.011; P = 0.48). In addition, acti-CT90 was significantly associated with mean RNFL thickness both in the elderly (⩾60 yr; β = -0.058; P = 0.002) and nonelderly (<60 yr; β = -0.054; P = 0.007).Conclusions: Acti-CT90, but not acti-ODI3%, was associated with mean RNFL thinning in participants irrespective of age in the elderly or nonelderly. Further prospective studies are required to investigate whether the prevention of hypoxic burden, which was shown as acti-CT90 in this study, is favorable for RNFL thinning.

Associations between Sleep-Disordered Breathing and Serum Uric Acid and Their Sex Differences: The Nagahama Study

Sleep-disordered breathing (SDB) is often accompanied by noncommunicable diseases (NCDs), including gout. However, the association between serum uric acid (sUA) levels and NCDs is complicated in patients with SDB. We aimed to clarify this issue utilizing large-scale epidemiological data. This community-based study included 9850 inhabitants. SDB and its severity were assessed by a 3% oxygen desaturation index (3% ODI) corrected for sleep duration using wrist actigraphy. The associations between sUA and moderate to severe SDB (MS-SDB) and sUA and NCDs in patients with MS-SDB were analyzed. A total of 7895 subjects were eligible. In females, the prevalence of MS-SDB increased according to an elevation in sUA levels even after adjusting for confounders, and sUA ≥ 5 mg/dL was the threshold. These were not found in males. There was a positive interaction between sUA ≥ 5 mg/dL and female sex for MS-SDB. In females with MS-SDB, the prevalence of diabetes mellitus (DM) increased according to an elevation in sUA levels, and those with sUA ≥ 5 mg/dL showed a higher prevalence of DM than their counterparts. There is a clear correlation between sUA levels and the severity of SDB, and elevated sUA poses a risk for DM in females with MS-SDB.

Residual excessive daytime sleepiness in patients with sleep apnea syndrome receiving continuous positive airway pressure in Japan: A single-center study

Excessive daytime sleepiness (EDS) is a symptom of sleep apnea syndrome (SAS). In some patients with SAS who undergo continuous positive airway pressure (CPAP) therapy, EDS persists (residual EDS). However, knowledge of residual EDS in Japan is limited. Therefore, we examined EDS as defined by the Japanese version of the Epworth Sleepiness Scale (a score of ≥11) before and after long-term (≥1 year) CPAP therapy in 490 patients with SAS. Good adherence to CPAP therapy was defined as its use for at least 4 h during 70% of the nights. The prevalence of residual EDS was 9.4%. Residual EDS was negatively associated with good adherence to CPAP therapy. Furthermore, the longer the CPAP therapy duration after initiation, the lower the prevalence of residual EDS. Therefore, the findings on the prevalence of residual EDS and its association with CPAP therapy in Japan are probably similar to those of other countries.

Good clinical response achieved by changing servo-ventilation devices in a patient with central sleep apnea: a case report

Servo-ventilation (SV) was developed for treating central sleep apnea. To date, primarily SV devices manufactured by Philips Respironics and ResMed are used. However, the difference in reaction to sleep-disordered breathing events between bilevel positive airway pressure AutoSV devices from Philips and adaptive SV devices from ResMed in clinical settings is unknown. Herein, we describe a case of central sleep apnea in which sleep-disordered breathing events were successfully controlled and sleepiness, sleep quality, and tolerance of the device were improved by changing from the bilevel positive airway pressure AutoSV device from Philips to the adaptive SV device from ResMed. Changing the SV devices can be a clinical option to appropriately control sleep-disordered breathing events in patients receiving SV therapy who present with persistent sleep-disordered breathing.

CITATION

Hamada S, Togawa J, Sunadome H, Nagasaki T, Hirai T, Sato S. Good clinical response achieved by changing servo-ventilation devices in a patient with central sleep apnea: a case report. J Clin Sleep Med. 2023;19(8):1557-1561.

Effects of using in-line bacterial filters with continuous positive airway pressure devices in patients with sleep disordered breathing

In June 2021, Philips Respironics first advised the use of in-line bacterial filters in response to a recall of continuous positive airway pressure (CPAP) devices. However, the effects of using in-line filters with CPAP devices have not yet been examined in a clinical setting. Here, we retrospectively evaluated 160 patients with sleep-disordered breathing (SDB) who voluntarily used in-line bacterial filters. Patients' perceptions of CPAP pressure after using in-line filters were investigated via a verbal interview. Patients described CPAP pressure as very weak (13, 8.1%), somewhat weak (42, 26.2%), unchanged (103, 64.4%), or somewhat strong (2, 1.3%). Five of the thirteen patients (38.5%) who described CPAP pressure as very weak discontinued the use of in-line filters. The apnea-hypopnea index obtained from the CPAP devices did not change after using in-line filters (n = 129, p = 0.85). Hence, although in-line bacterial filters could change patients' perceptions of CPAP pressure, they did not influence SDB control.

Enhanced phase-amplitude coupling of human electrocorticography selectively in the posterior cortical region during rapid eye movement sleep

The spatiotemporal dynamics of interaction between slow (delta or infraslow) waves and fast (gamma) activities during wakefulness and sleep are yet to be elucidated in human electrocorticography (ECoG). We evaluated phase-amplitude coupling (PAC), which reflects neuronal coding in information processing, using ECoG in 11 patients with intractable focal epilepsy. PAC was observed between slow waves of 0.5-0.6 Hz and gamma activities, not only during light sleep and slow-wave sleep (SWS) but even during wakefulness and rapid eye movement (REM) sleep. While PAC was high over a large region during SWS, it was stronger in the posterior cortical region around the temporoparietal junction than in the frontal cortical region during REM sleep. PAC tended to be higher in the posterior cortical region than in the frontal cortical region even during wakefulness. Our findings suggest that the posterior cortical region has a functional role in REM sleep and may contribute to the maintenance of the dreaming experience.

The Effects of Changing Continuous Positive Airway Pressure Devices in Japanese Patients with Obstructive Sleep Apnea: A Case Series

Background The effects of continuous positive airway pressure (CPAP) devices on obstructive sleep apnea (OSA) in Japanese patients have not been reported. We assessed the effects of changing CPAP devices (from the Philips Respironics device to the ResMed device) on the control of OSA. Methods We retrospectively examined 13 patients with OSA who voluntarily changed from the Philips Respironics device to the ResMed device due to a Philips Respironics CPAP device recall. Data on the apnea-hypopnea index (AHI) were obtained from the CPAP devices for three months before and after changing the devices. Results The AHI obtained from the CPAP devices significantly decreased from 4.4 (3.1-10.7) events/h to 2.0 (0.8-3.6) events/h when patients changed devices (P=0.022). The AHI decreased to <5 events/h after changing devices in 4 patients, whereas it had been ≥5 events/h before changing devices in 6 patients. Conclusion Changing CPAP devices can decrease the AHI.

Diagnostic value of an algorithm for autoimmune epilepsy in a retrospective cohort

Purpose

This study aims to propose a diagnostic algorithm for autoimmune epilepsy in a retrospective cohort and investigate its clinical utility.

Methods

We reviewed 60 patients with focal epilepsy with a suspected autoimmune etiology according to board-certified neurologists and epileptologists. To assess the involvement of the autoimmune etiology, we used the patients' sera or cerebrospinal fluid (CSF) samples to screen for antineuronal antibodies using rat brain immunohistochemistry. Positive samples were analyzed for known antineuronal antibodies. The algorithm applied to assess the data of all patients consisted of two steps: evaluation of clinical features suggesting autoimmune epilepsy and evaluation using laboratory and imaging findings (abnormal CSF findings, hypermetabolism on fluorodeoxyglucose-positron emission tomography, magnetic resonance imaging abnormalities, and bilateral epileptiform discharges on electroencephalography). Patients were screened during the first step and classified into five groups according to the number of abnormal laboratory findings. The significant cutoff point of the algorithm was assessed using a receiver-operating characteristic curve analysis.

Results

Fourteen of the 60 patients (23.3%) were seropositive for antineuronal antibodies using rat brain immunohistochemistry. Ten patients had antibodies related to autoimmune epilepsy/encephalitis. The cutoff analysis of the number of abnormal laboratory and imaging findings showed that the best cutoff point was two abnormal findings, which yielded a sensitivity of 78.6%, a specificity of 76.1%, and an area under the curve of 0.81.

Conclusion

The proposed algorithm could help predict the underlying autoimmune etiology of epilepsy before antineuronal antibody test results are available.

Ictal direct current shifts contribute to defining the core ictal focus in epilepsy surgery

Identifying the minimal and optimal epileptogenic area to resect and cure is the goal of epilepsy surgery. To achieve this, EEG analysis is recognized as the most direct way to detect epileptogenic lesions from spatiotemporal perspectives. Although ictal direct-current shifts (below 1 Hz) and ictal high-frequency oscillations (above 80 Hz) have received increasing attention as good indicators that can add more specific information to the conventionally defined seizure-onset zone, large cohort studies on postoperative outcomes are still lacking. This work aimed to clarify whether this additional information, particularly ictal direct-current shifts which is assumed to reflect extracellular potassium concentration, really improve postoperative outcomes. To assess the usefulness in epilepsy surgery, we collected unique EEG data sets recorded with a longer time constant of 10 s using an alternate current amplifier. Sixty-one patients (15 with mesial temporal lobe epilepsy and 46 with neocortical epilepsy) who had undergone invasive presurgical evaluation for medically refractory seizures at five institutes in Japan were retrospectively enrolled in this study. Among intracranially implanted electrodes, the two core electrodes of both ictal direct-current shifts and ictal high-frequency oscillations were independently identified by board-certified clinicians based on unified methods. The occurrence patterns, such as their onset time, duration, and amplitude (power) were evaluated to extract the features of both ictal direct-current shifts and ictal high-frequency oscillations. Additionally, we examined whether the resection ratio of the core electrodes of ictal direct-current shifts and ictal high-frequency oscillations independently correlated with favourable outcomes. A total of 53 patients with 327 seizures were analyzed for wide-band EEG analysis, and 49 patients were analyzed for outcome analysis. Ictal direct-current shifts were detected in the seizure-onset zone more frequently than ictal high-frequency oscillations among both patients (92% versus 71%) and seizures (86% versus 62%). Additionally, ictal direct-current shifts significantly preceded ictal high-frequency oscillations in patients exhibiting both biomarkers, and ictal direct-current shifts occurred more frequently in neocortical epilepsy patients than in mesial temporal lobe epilepsy patients. Finally, although a low corresponding rate was observed for ictal direct-current shifts and ictal high-frequency oscillations (39%) at the electrode level, complete resection of the core area of ictal direct-current shifts significantly correlated with favourable outcomes, similar to ictal high-frequency oscillation outcomes. Our results provide a proof of concept that the independent significance of ictal direct-current shifts from ictal high-frequency oscillations should be considered as reliable biomarkers to achieve favourable outcomes in epilepsy surgery. Moreover, the different distribution of the core areas of ictal direct-current shifts and ictal high-frequency oscillations may provide new insights into the underlying mechanisms of epilepsy, in which not only neurons but also glial cells may be actively involved via extracellular potassium levels.

Exacerbation of ventricular arrhythmias by continuous positive airway pressure treatment in idiopathic dilated cardiomyopathy

Continuous positive airway pressure (CPAP) therapy can be beneficial in patients with obstructive sleep apnea (OSA) and cardiovascular diseases, reducing arrhythmia frequency and improving cardiac function. We describe a case of moderate OSA with idiopathic dilated cardiomyopathy, in which the frequency of premature ventricular contraction (PVC) and non-sustained ventricular tachycardia (NSVT) increased immediately after initiating CPAP therapy. Although PVC and NSVT are benign cardiac arrhythmias, they are associated with an increased risk of sustained lethal ventricular tachyarrhythmias. Therefore, when initiating CPAP therapy, the possibility of increased arrhythmia should be considered.

[A case of Creutzfeldt-Jakob disease presenting with nonconvulsive status epilepticus in the early stages]

A 64-year-old Japanese woman presented with 1 week of recurrent convulsive seizures. At the time of admission, she was in a coma and did not present with convulsions. Intravenous diazepam administration improved her consciousness, although severe psychomotor excitement developed. Brain MRI demonstrated diffusion restriction in the cerebral cortex of the right hemisphere. Electroencephalography (EEG) showed periodic discharges centered around the parietal regions with right-sided dominance. Nonconvulsive status epilepticus (NCSE) was suspected, and the patient was actively treated with anti-epileptic drugs. She developed akinetic mutism and generalized myoclonus 1 month after admission. Follow-up EEG studies disclosed periodic synchronous discharges. Abnormal prion protein in the cerebral fluid was detected using a real-time quaking-induced conversion assay. The clinical diagnosis in the present case was sporadic Creutzfeldt-Jakob disease (CJD). Seizures as an initial symptom in patients with CJD are relatively rare. Our case suggests that CJD should be considered as a differential diagnosis when a patient presents with refractory NCSE.

Engagement of cortico-cortical and cortico-subcortical networks in a patient with epileptic spasms: An integrated neurophysiological study

OBJECTIVE

We aimed to delineate the engagement of cortico-cortical and cortico-subcortical networks in the generation of epileptic spasms (ES) using integrated neurophysiological techniques.

METHODS

Seventeen-year-old male patient with intractable ES underwent chronic subdural electrode implantation for presurgical evaluation. Networks were evaluated in ictal periods using high-frequency oscillation (HFO) analysis and in interictal periods using magnetoencephalography (MEG) and simultaneous electroencephalography, and functional magnetic resonance imaging (EEG-fMRI). Cortico-cortical evoked potentials (CCEPs) were recorded to trace connections among the networks.

RESULTS

Ictal HFO revealed a network comprising multilobar cortical regions (frontal, parietal, and temporal), but sparing the positive motor area. Interictally, MEG and EEG-fMRI revealed spike-and-wave-related activation in these cortical regions. Analysis of CCEPs provided evidence of connectivity within the cortico-cortical network. Additionally, EEG-fMRI results indicate the involvement of subcortical structures, such as bilateral thalamus (predominantly right) and midbrain.

CONCLUSIONS

In this case study, integrated neurophysiological techniques provided converging evidence for the involvement of a cortico-cortical network (sparing the positive motor area) and a cortico-subcortical network in the generation of ES in the patient.

SIGNIFICANCE

Cortico-cortical and cortico-subcortical pathways, with the exception of the direct descending corticospinal pathway from the positive motor area, may play important roles in the generation of ES.

Atypical Familial Amyotrophic Lateral Sclerosis with Slowly Progressing Lower Extremities-predominant Late-onset Muscular Weakness and Atrophy

Objective Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease characterized by the progressive loss of the upper and lower motor neurons that progresses to paralysis of almost all skeletal muscles of the extremities, bulbar, and respiratory system. Although most ALS cases are sporadic, about 10% are dominantly inherited. We herein report an atypical phenotype of familial ALS (fALS). To elucidate the phenotype-genotype correlation of this atypical phenotype of fALS, clinical and genetic investigations were performed. Methods and Patients Five sibling patients (three men, two women) from a Japanese family and one healthy sibling (a woman) were clinically interviewed and examined. Genetic analyses, including genome-wide linkage analyses and whole-exome sequencing, were performed using genomic DNA extracted from the peripheral blood samples of these siblings. Results The clinical features of fALS are characterized by slow progression (mean duration of the disease±standard deviation [SD]: 19.6±3.9 years) and lower extremities-predominant late-onset muscular weakness (mean onset of muscular weakness±SD: 52.8±2.6 years). Genetic analyses revealed novel heterozygous missense mutations of c.2668C>T, p.R890C in the PLEC gene and c.421G>C, p.V141L in the ST3GAL6 gene in all affected siblings. Conclusion A new atypical fALS family with a benign clinical course is herein reported. We identified two candidate gene mutations of PLEC and ST3GAL6 linked to this phenotype.

[Proposal of a diagnostic algorithm for autoimmune epilepsy: preliminary investigation of its utility]

The epilepsy syndrome of autoimmune etiology, namely, autoimmune epilepsy has attracted attention in recent years, as was reflected in the new etiology of "immunity" in the Epilepsy Classification of the International League Against Epilepsy (2017). However, no specific tests other than neuronal antibodies have been established. We proposed a diagnostic algorithm for autoimmune epilepsy and preliminarily investigated its clinical utility. We applied this algorithm to 70 patients who were suspected as having autoimmune epilepsy from clinical symptoms and laboratory findings in our institute. At least one of the three neuronal antibodies (antibodies to N-methyl-D-aspartic acid receptor (NMDAR), glutamic acid decarboxylase (GAD), and voltage-gated potassium channels (VGKC) complex) was evaluated. In this two-step algorithm, the patients were initially screened by clinical features and then evaluated by laboratory findings (neuronal antibodies, cerebrospinal fluid (CSF), MRI, FDG-PET). The results of preliminary application of the algorithm are described. One of the three neuronal antibodies was positive in 13 patients. In this preliminary investigation, it was suggested that two or more abnormal findings in the diagnostic tests (CSF, MRI, FDG-PET) favors the diagnosis of autoimmune epilepsy. On the other hand, two patients with a positive neuronal antibody test failed the first step (clinical features), partly because epilepsy was not the major manifestation of autoimmune encephalitis (VGKC complex antibody) or due to a relatively low titer of the antibody (GAD antibody). Recruitment of the patient cohort with comprehensive neuronal antibody testing and multivariate analysis of laboratory findings is warranted for validation and modification of the proposed algorithm.

Bilateral optic neuropathy with bilateral putaminal lesions: a case report

Bilateral optic neuropathy with bilateral putaminal lesions may be caused by methanol or cyanide poisoning or mitochondrial disorders including Leber hereditary optic neuropathy and Leigh syndrome. We report the case of a 34-year-old Japanese man who developed bilateral visual loss 5 days after the development of gastrointestinal symptoms. Magnetic resonance imaging of the brain on admission revealed high-intensity signal areas in the bilateral putamina on diffusion-weighted and T2-weighted images as well as a high-intensity signal area in the left middle cerebellar peduncle that had been identified 3 years previously. We diagnosed bilateral optic neuropathy with bilateral putaminal lesions caused by preceding infection-triggered demyelination. We administered methylprednisolone, but his vision did not recover.

Global aphasia without hemiparesis caused by a dural arteriovenous fistula

A 61-year-old Japanese woman with chronic renal failure suddenly became silent at the end of hemodialysis. On a neurological examination, she was unable to respond to one-step commands, state the names of objects, repeat single words, read words aloud or write her name. Because she exhibited no paralysis of the extremities, we diagnosed her as having global aphasia without hemiparesis (GAWH). Cerebral angiography showed a dural arteriovenous fistula (AVF) in the left isolated transverse sinus with leptomeningeal venous drainage (Borden type 3, Lalwani grade 4). This case highlights dural AVF as an etiology of GAWH.

De novo acute myelogenous leukemia with trilineage myelodysplasia associated with t(8;21)(q22;q22)

We describe a rare case of de novo acute myelogenous leukemia with trilineage myelodysplasia (AML/TMDS) associated with t(8;21)(q22;q22). The patient was admitted to our hospital with leukocytopenia. AML/TMDS was diagnosed by excess myeloblasts and morphological findings of bone marrow. The karyotype revealed 45, X, -Y, t(8;21)(q22;q22) in 17 of 20 analyzed mitoses, and also AML1/MTG8 transcripts were detected by the reverse transcription polymerase chain reaction (RT-PCR) method. The patient achieved a complete remission with a combination chemotherapy of daunorubicin, cytarabine, and prednisolone. This case suggests that t(8;21)(q22;q22) may participate in the pathogenesis of AML/TMDS, although this type is usually found as one of the chromosomal abnormalities in de novo acute myelogenous leukemia (AML) with maturation.

[An aortic valve-sparing procedures (remodeling) for a patient with annuloaortic ectasia: a case report]

A 51-year-old man with annuloaortic ectasia and aortic regurgitation, who did not have Marfan syndrome, underwent an aortic valve-sparing root reconstruction (remodeling). All three sinuses were excised and then the ascending aorta was replaced with a 30 mm collagen-impregnated Dacron graft, one of which ends were scalloped to reproduce pseudosinus. Each coronary artery orifice was anastomosed to the graft with Carrel patch method. Post-operative angiogram showed no aortic regurgitation and no pseudosinus formation, because the graft was slightly larger than the optimal one. The NYHA functional class has been improved III to I 18 months after the operation.

[A case report: surgical treatment of hypertrophic obstructive cardiomyopathy with acute hemodynamic deterioration due to chordae rupture of the mitral valve]

A 70-year-old woman was found to have new heart systolic murmur and was transferred to our hospital for the treatment of high fever and dyspnea. The chest X ray showed cardiomegaly (CTR 63%) and marked pulmonary congestion. The UCG revealed that there was no evidence of infective endocarditis, but there was hypertrophic obstructive cardiomyopathy with the left ventricular pressure gradient of 90 mmHg accompanied by mitral regurgitation (grade 3/4). Two weeks after the admission, mitral regurgitation progressed due to chordae rupture confirmed by UCG. Transaortic subvalvular myectomy and mitral valve replacement were underwent. Post-operative electrocardiogram demonstrated right and left anterior bandle branch block. Eleven months after the operation left ventricular outflow pressure gradient was not detected by echocardiogram and she has been in I/IV NYHA functional class.

[A case of papillary muscle rupture associated with acute inferior myocardial infarction]

A sixty-year-old man was admitted to our hospital due to prolonged left anterior chest oppression and hypotention. The electrocardiogram revealed acute inferior myocardial infarction, confirmed by the coronary angiography which showed occluded right coronary artery (RCA) at the segment 4AV. The intra-coronary pro-urokinase infusion and coronary angioplasty successfully revascularized the occluded 4AV segment. Although the 4AV segment perfused small area, he developed severe pulmonary edema on the second hospital day. A transesophageal echocardiography revealed severe mitral regurgitation due to posterior mitral valve prolapse by the ruptured tendineae with a mobile mass. The damaged mitral valve was replaced by the prosthetic mechanical valve (SJM 25M), resulted in stable hemodynamic state. He discharged one month after the operation.

Left ventricular thrombosis following coronary artery bypass grafting in a patient with nephrotic syndrome: report of a case

We present herein the case of a 63-year-old man with nephrotic syndrome who developed an apical infarction 4 days after undergoing coronary artery bypass grafting. Echocardiography done 2 weeks postoperatively revealed a left ventricular thrombus which was successfully removed. He has no further thrombotic events since anticoagulant therapy was initiated.

[Studies on faint attack due to arrhythmias with Holter electrocardiogram]

Out of 1,400 Holter ECGs, 15 records revealed arrhythmias which would be responsible for faint attack, including 8 sick sinus syndrome with cardiac arrest, 4 non-sustained ventricular tachycardia (VT), 2 paroxysmal atrial fibrillation and 1 paroxysmal supraventricular tachycardia. All of cardiac arrest corresponding to faint attack lasted for longer than 4 sec, and an averaged duration of the arrest was 5.8 +/- 2.3 sec. This was significantly longer than that with no subjective symptoms, 3.4 +/- 0.7 sec. Duration and rate of VT did not show any significant relationship with faint attack. The result suggests that cardiac arrest is mostly responsible for arrhythmia-induced involvement of cerebral circulation and faint attack. It is also suggested that cardiac arrest longer than 4 sec should be extensively treated including pacemaker implantation.