Clinical characteristics of benign paroxysmal positional vertigo after traumatic brain injury.

INTRODUCTION: The aim of the present study was to evaluate the characteristics of brain injury and to assess the relationship between them and treatment outcomes in patients with traumatic benign paroxysmal positional vertigo (t-BPPV). MATERIALS AND METHODS: Sixty-three consecutive patients who were diagnosed with BPPV within 2 weeks after head trauma were included. RESULTS: Cerebral concussion, intracranial hemorrhages (ICH), skull fracture without ICH, and hemorrhagic contusion were observed in 68%, 24%, 5%, and 3% of t-BPPV patients, respectively. BPPV with single canal involvement was observed in 52 (83%) patients and that with multiple canal involvement was observed in 11 (17%) patients. The number of treatment sessions was not significantly different according to the cause of head trauma (p = 0.252), type of brain injury (p = 0.308) or location of head trauma (p = 0.287). The number of recurrences was not significantly different according to the cause of head trauma (p = 0.308), type of brain injury (p = 0.536) or location of head trauma (p = 0.138). CONCLUSION: The present study demonstrated that there were no significant differences in treatment sessions until resolution and the mean number of recurrences according to the type of brain injury.

Amplitude modulating frequency overrides carrier frequency in tACS-induced phosphene percept.

The amplitude modulated (AM) neural oscillation is an essential feature of neural dynamics to coordinate distant brain areas. The AM transcranial alternating current stimulation (tACS) has recently been adopted to examine various cognitive functions, but its neural mechanism remains unclear. The current study utilized the phosphene phenomenon to investigate whether, in an AM-tACS, the AM frequency could modulate or even override the carrier frequency in phosphene percept. We measured the phosphene threshold and the perceived flash rate/pattern from 12 human subjects (four females, aged from 20-44 years old) under tACS that paired carrier waves (10, 14, 18, 22 Hz) with different envelope conditions (0, 2, 4 Hz) over the mid-occipital and left facial areas. We also examined the phosphene source by adopting a high-density stimulation montage. Our results revealed that (1) phosphene threshold was higher for AM-tACS than sinusoidal tACS and demonstrated different carrier frequency functions in two stimulation montages. (2) AM-tACS slowed down the phosphene flashing and abolished the relation between the carrier frequency and flash percept in sinusoidal tACS. This effect was independent of the intensity change of the stimulation. (3) Left facial stimulation elicited phosphene in the upper-left visual field, while occipital stimulation elicited equally distributed phosphene. (4) The near-eye electrodermal activity (EDA) measured under the threshold-level occipital tACS was greater than the lowest power sufficient to elicit retinal phosphene. Our results show that AM frequency may override the carrier frequency and determine the perceived flashing frequency of AM-tACS-induced phosphene.

Otological aspects of NLRP3-related autoinflammatory disorder focusing on the responsiveness to anakinra.

OBJECTIVES: Gradually progressive sensorineural hearing loss (SNHL) is a prevalent sensory defect. It is generally untreatable, making rehabilitation by hearing aid or cochlear implantation the only option. However, SNHL as one of the symptoms of the hereditary autoinflammatory systemic disease cryopyrin-associated periodic syndrome, or as the only symptom of the cochlea-specific form (DFNA34), was suggested to respond to IL-1 antagonist (anakinra) therapy, which ameliorates NLRP3 variants-induced over-secretion of IL-1ß. We analysed genotypic and phenotypic spectrum of cryopyrin-associated periodic syndrome or DFNA34, specifically focusing on the responsiveness of SNHL to anakinra. METHODS: Seventeen families diagnosed with either cryopyrin-associated periodic syndrome or DFNA34 were recruited. Genotyping and phenotyping including audiogram, MRI findings, and in vitro IL-1ß assay were performed. RESULTS: Our cohort had an etiologic homogeneity of 94.1% to NLRP3 variants and a high de novo occurrence (84.6%). We identified the second DNFA34 pedigree worldwide with a novel NLRP3 variant supported by in vitro analysis. Significant improvement of hearing status against the natural course, showing response to anakinra, was identified in three probands, one of whom used to have severe SNHL. Hearing threshold worse than 60 dB at the start of anakinra and cochlear enhancement on brain MRI seemed to be related with poor audiologic prognosis and responsiveness to anakinra therapy despite stabilized systemic symptoms and inflammatory markers. CONCLUSION: We propose a constellation of biomarkers comprising NLRP3 genotypes, hearing status at diagnosis, and cochlear radiological findings as prognostic factors of hearing status after anakinra treatment and possibly as sensitive parameters for treatment dosage adjustment.

Estimation of the reproduction number of influenza A(H1N1)pdm09 in South Korea using heterogeneous models.

BACKGROUND: The reproduction number is one of the most crucial parameters in determining disease dynamics, providing a summary measure of the transmission potential. However, estimating this value is particularly challenging owing to the characteristics of epidemic data, including non-reproducibility and incompleteness. METHODS: In this study, we propose mathematical models with different population structures; each of these models can produce data on the number of cases of the influenza A(H1N1)pdm09 epidemic in South Korea. These structured models incorporating the heterogeneity of age and region are used to estimate the reproduction numbers at various terminal times. Subsequently, the age- and region-specific reproduction numbers are also computed to analyze the differences illustrated in the incidence data. RESULTS: Incorporation of the age-structure or region-structure allows for robust estimation of parameters, while the basic SIR model provides estimated values beyond the reasonable range with severe fluctuation. The estimated duration of infectious period using age-structured model is around 3.8 and the reproduction number was estimated to be 1.6. The estimated duration of infectious period using region-structured model is around 2.1 and the reproduction number was estimated to be 1.4. The estimated age- and region-specific reproduction numbers are consistent with cumulative incidence for corresponding groups. CONCLUSIONS: Numerical results reveal that the introduction of heterogeneity into the population to represent the general characteristics of dynamics is essential for the robust estimation of parameters.

Renal Syndromic Hearing Loss Is Common in Childhood-onset Chronic Kidney Disease.

BACKGROUND: Hearing loss (HL) in children may adversely affect their development. HL is more prevalent in patients with chronic kidney disease (CKD) than in the general population. This study evaluated the prevalence of HL and its underlying diseases in patients with childhood-onset in CKD. METHODS: In this retrospective study of a tertiary referral center, childhood-onset CKD patients (stage 2-5, age at onset of renal symptom < 18 years) were recruited. We referred to the "renal" syndromic HL as cases with genetic or syndromic diseases, or extra-renal anomalies in addition to HL and CKD. RESULTS: A total of 421 patients (male:female = 279:142) were reviewed according to the causes of CKD: congenital anomalies of the kidney and urinary tract (CAKUT; n = 184, 43.7%), glomerulopathies (GP; n = 105, 24.9%), cystic kidney diseases (CYST; n = 39, 9.3%), perinatal problems (PP; n = 29, 6.9%), and others (n = 64, 15.2%). HL was detected in 82 (19.5%) patients, including 51 (12.1%) patients with sensorineural hearing loss (SNHL), 30 (7.1%) with conductive hearing loss (CHL), and 1 patient with mixed HL. The prevalence of HL in each group was as follows: 16.8% in the CAKUT group, 28.6% in the GP group, 12.8% in the CYST group, 24.1% in the PP group, and 14.1% in the others group. HL was more common in higher CKD stages, especially CHL in end-stage renal disease. SNHL was more prevalent in CKD from GP. Of the 82 patients with HL, 50% had renal syndromic HL: 58.8% of SNHL and one-third of CHL were renal syndromic HL. CONCLUSION: One-fifth of the childhood-onset CKD had HL. Collectively, renal syndromic HL comprised half of the HL in this study. To improve the quality of life in patients with childhood-onset CKD, we suggest that HL should be considered, requiring surveillance, and if necessary, early intervention.

Fault Detection of Bearing Systems through EEMD and Optimization Algorithm.

This study proposes a fault detection and diagnosis method for bearing systems using ensemble empirical mode decomposition (EEMD) based feature extraction, in conjunction with particle swarm optimization (PSO), principal component analysis (PCA), and Isomap. First, a mathematical model is assumed to generate vibration signals from damaged bearing components, such as the inner-race, outer-race, and rolling elements. The process of decomposing vibration signals into intrinsic mode functions (IMFs) and extracting statistical features is introduced to develop a damage-sensitive parameter vector. Finally, PCA and Isomap algorithm are used to classify and visualize this parameter vector, to separate damage characteristics from healthy bearing components. Moreover, the PSO-based optimization algorithm improves the classification performance by selecting proper weightings for the parameter vector, to maximize the visualization effect of separating and grouping of parameter vectors in three-dimensional space.

Genotyping of 22 blood group antigen polymorphisms and establishing a national recipient registry in the Korean population.

It is often difficult for standard blood banks in Korea to supply adequate amounts of blood for patients with rare phenotype. Moreover, the definition of a blood in need is ambiguous, and much remains to be learned. In this study, we determined the prevalence of various red blood cell (RBC) antigens from a donor viewpoint and estimated the demand for specific antigen-negative blood from a patient viewpoint. Our data will aid the establishment of a Rare Blood Program in Korea (KRBP). RBC genotyping of 419 blood donors was performed using a Lifecodes RBC/RBC-R typing kit (Immucor, Norcross, GA). A national recipient registry website has been established. Each hospital-based blood bank voluntarily enters data on antibodies detected and identified and the outcomes of specific antigen testing. We calculated the availabilities of specific antigen-negative blood components based on these registry data and predicted the prevalence of RBC antigens via RBC genotyping. The prevalences of various RBC antigens in the D-negative population were determined for the first time, and the Cartwright, Scianna, Dombrock, Colton, Landsteiner-Wiener, Cromer, and Knops blood group systems were identified. The availabilities of specific antigen-negative units differed when calculations were based on serotyping or genotyping, especially in the D-negative group. Data on the prevalences of various blood antigens are essential for estimating the availabilities of blood components that are appropriate for use by patients expressing relevant antibodies. Then, blood banks would be able to efficiently supply safe blood products.

Reconstruction of Head and Neck Capillary Malformations With Free Perforator Flaps for Aesthetic Purposes.

BACKGROUND: Capillary malformations (CMs) are composed of dilated capillaries and venules in the dermis layer. They appear as pink- or purple-colored lesions on the involved skin and usually follow a dermatomal distribution. Generally, laser treatment is considered the treatment of choice; however, in some patients, a surgical approach should be considered. This article presents the authors' experiences with free perforator flap transfer to the head and neck after resection of CMs for aesthetic purposes. PATIENTS AND METHODS: A total of 5 patients with CMs on their head and neck underwent operations for aesthetic purposes. After lesion debulking, defect sizes were measured and precise flaps were designed. A primary flap-thinning procedure was needed in obese patients before flap inset. The donor site was closed primarily in 4 cases. RESULTS: Thoracodorsal artery perforator free flaps were performed in all patients. The average size of harvested flaps was 146.8 cm. All flaps survived without recurrence of CM on the skin paddle of the transferred flap. Aesthetic restoration and high patient satisfaction were achieved after the surgery. CONCLUSIONS: The authors used free flaps to improve aesthetic outcomes, which have been used for reconstruction after trauma and malignancy. Free perforator flap transfer should be considered a valuable option for head and neck CMs.

Stereotactic body radiotherapy for oligometastases confined to the para-aortic region: clinical outcomes and the significance of radiotherapy field and dose.

We retrospectively reviewed 88 patients with oligometases in the para-aortic region from any controlled primary tumor site who were treated with stereotactic body radiotherapy (SBRT). The 5-year local control, disease-free survival, and overall survival rates were 83%, 31%, and 41%, respectively. A 90% tumor-control probability was predicted at a biological effective dose of 90 Gy. Severe gastrointestinal toxicities (grade ≥3) were observed in 2 of 88 patients (1%). The results of this study are limited by the retrospective nature of the study but could serve as the background and rationale for future prospective trials on SBRT-based treatment for oligometastses.

Low Hepatic Toxicity in Primary and Metastatic Liver Cancers after Stereotactic Ablative Radiotherapy Using 3 Fractions.

This study evaluated the incidence of hepatic toxicity after stereotactic ablative radiotherapy (SABR) using 3 fractions to the liver, and identified the predictors for hepatic toxicity. We retrospectively reviewed 78 patients with primary and metastatic liver cancers, who underwent SABR using 3 fractions between 2003 and 2011. To examine the incidence of hepatic toxicity, we defined newly developed hepatic toxicity≥grade 2 according to the National Cancer Institute Common Terminology Criteria for Adverse Events v4.0 within 3 months after the end of SABR as a significant adverse event. To identify the predictors for hepatic toxicity, we analyzed several clinical and dosimetric parameters (rV5Gy-rV35Gy: normal liver volume receiving

Clinical result of stereotactic radiosurgery for spinal metastasis from hepatocellular carcinoma: comparison with conventional radiation therapy.

We investigated the clinical outcome following stereotactic radiosurgery (SRS) for spinal metastasis from hepatocellular carcinoma (HCC) and compared it with that of conventional radiation therapy (cRT). Thirty-nine metastatic spine tumors from 27 HCC patients were treated with SRS from 2002 to 2011. Their medical records and radiological data were retrospectively analyzed. Median tumor volume was 49.7 cc, and a mean marginal dose of 28.7 Gy was delivered to the tumor mass. We analyzed overall survival (OS), local progression-free survival, and the rate of pain control following SRS. Factors relating to clinical outcomes were also investigated. Clinical results following cRT were obtained from 32 patients. The cRT protocol consisted of 30 Gy in 10 fractions or 39 Gy in 13 fractions. OS and local progression-free survival were compared between SRS and cRT. OS was a median of 7 months following SRS. Significant prognostic factors relating to OS included Child-Pugh class and Karnofsky performance scale. Tumor recurrence was noted in nine lesions during follow-up. The median local progression-free survival was 7 months. Previous irradiation was a significant prognostic factor for local recurrence (P = 0.043). The overall pain control rate was 85 % and no factors were found to be significantly correlated with the pain control rate. The median OS was 3 months in the cRT group and 7 months in the SRS group (P = 0.035). The median local progression-free survival was 2.0 months in the cRT group, and 7.0 months in the SRS group, which were significantly different (P = 0.033). SRS showed better local control than cRT in the treatment of HCC spinal metastasis.

Is late seroma a phenomenon related to textured implants? A report of rare complications and a literature review.

BACKGROUND: Late seroma is an infrequent complication that manifests as fluid collection in the periprosthetic space at least 1 year after breast enlargement surgery. Interest in late seroma has grown with the potential connection between breast implants and anaplastic large cell lymphoma (ALCL), which presents with clinical symptoms similar to those of late seroma. This report presents a case of late seroma experienced by a patient with a history of multiple implant ruptures and a review of the relevant literature. METHODS: Details are reported for a patient who presented with sudden swelling of an augmented breast that was initially suspected to be symptomatic of ALCL. A literature search of PubMed regarding this phenomenon also was conducted. RESULTS: The literature review identified 14 articles on late seroma involving 60 patients, including the reported case. Analyses included epidemiology, etiology, and management strategy. Although a detailed statistical analysis was not performed, 55 cases (92 %) of late seroma occurred that involved patients with textured implants. No evidence-based guideline for the management of late seroma has been established, although the patients were managed successfully in all cases using various strategies. CONCLUSIONS: The reported case and data from the literature provide evidence of a relationship between textured implant use and late seroma. Based on their review, the authors offer "sequential treatment steps," from conservative treatment to surgical management, which will be helpful for successful management of future late seroma cases. However, further study is needed to clarify the relationship, if any, between a particular type of textured implant and the development of late seroma. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Clinical diagnoses of patients showing caloric inversion.

OBJECTIVES: When air irrigation is used for caloric stimulation in patients with a perforated ear, warm irrigation may elicit a nystagmus that initially beats in the opposite direction of what is expected for warm irrigations, which is referred to as "caloric inversion". This study aimed to investigate the disease group in which caloric inversion appeared in patients who underwent caloric testing and to classify the patterns of caloric inversion. METHODS: We conducted a retrospective review of bithermal caloric test results that were collected in our dizziness clinic between 2005 and 2022. Caloric inversion was defined when nystagmus induced by caloric stimulation appeared in the opposite direction to that expected. The incidence of caloric inversion among all patients who underwent bithermal caloric tests was calculated. To confirm the clinical diagnoses of the patients with caloric inversion, their clinical records were reviewed. RESULTS: Out of 9923 patients who underwent bithermal caloric tests, 29 patients (0.29%) showed a caloric inversion. The most common clinical diagnosis was chronic otitis media (21 of 29, 72%). Of the 21 patients with chronic otitis media, 20 patients showed a caloric inversion by warm air irrigation and one patient showed caloric inversion by cold air stimulation. Patients with clinical diagnoses other than chronic otitis media such as sudden sensorineural hearing loss, benign paroxysmal vertigo of childhood and recurrent vestibulopathy showed caloric inversion by warm air irrigation. Caloric inversion by warm water irrigation was observed in patients with lateral semicircular canal cupulopathy and recurrent vestibulopathy. Two patients (one with Meniere's disease and one with age-related dizziness) showed caloric inversion by cold water irrigation. CONCLUSION: Caloric inversion can be observed in various diseases other than chronic otitis media with tympanic membrane perforation. Special care should be taken in the interpretation of caloric test results. LEVEL OF EVIDENCE: Level 4.

Severe intestinal toxicity after stereotactic ablative radiotherapy for abdominopelvic malignancies.

PURPOSE: The purpose of this study is to identify the predictors for severe intestinal toxicity (IT) in patients with abdominopelvic malignancies treated with three fractions of stereotactic ablative radiotherapy (SABR). METHODS: From 2001 to 2011, 202 patients with abdominopelvic malignancies were treated with curative-intent SABR. Among these, we retrospectively reviewed the clinical records of 55 patients with the presence of the intestine that received a dose ≥20 % of the prescribed dose. The total dose ranged from 33 to 60 Gy in three fractionations (median dose, 45 Gy). We analyzed the clinical and dosimetric parameters for severe IT ≥ grade 3 according to the National Cancer Institute Common Toxicity Criteria v4.0: V(20-35) (volume of the intestine that received xGy) and D(max) (maximum point dose). RESULTS: Severe IT was found in six patients (the median time, 3 months). V(25) was the best dosimetric predictor for severe IT (P = 0.004). With V(25) ≤ 20 ml, severe IT decreased from 50 to 4 %. SABR duration was the best clinical predictor. Severe IT decreased in patients who received SABR at 4-8 days than on three consecutive days (0 vs. 18 %, P = 0.037). CONCLUSIONS: Following three fractions of SABR, V(25) is a valuable predictor of severe IT. And SABR would be conducted with a treatment interval of at least 48 h if possible.

Feasibility and efficacy of stereotactic ablative radiotherapy for Barcelona Clinic Liver Cancer-C stage hepatocellular carcinoma.

The purpose of this study was to assess the feasibility and efficacy of stereotactic ablative radiotherapy (SABR) for liver tumor in patients with Barcelona Clinic Liver Cancer (BCLC)-C stage hepatocellular carcinoma (HCC). We retrospectively reviewed the medical records of 35 patients between 2003 and 2011. Vascular invasion was diagnosed in 32 patients, extrahepatic metastases in 11 and both in 8. Thirty-two patients were categorized under Child-Pugh (CP) class A and 3 patients with CP class B. The median SABR dose was 45 Gy (range, 30-60 Gy) in 3-5 fractions. The median survival time was 14 months. The 1- and 3-yr overall survival (OS) rate was 52% and 21%, respectively. On univariate analysis, CP class A and biologically equivalent dose ≥ 80 Gy(10) were significant determinants of better OS. Severe toxicity above grade 3, requiring prompt therapeutic intervention, was observed in 5 patients. In conclusion, SABR for BCLC-C stage HCC showed 1-yr OS rate of 52% but treatment related toxicity was moderate. We suggest that patients with CP class A are the best candidate and at least SABR dose of 80 Gy(10) is required for BCLC-C stage.

Fault detection of roller-bearings using signal processing and optimization algorithms.

This study presents a fault detection of roller bearings through signal processing and optimization techniques. After the occurrence of scratch-type defects on the inner race of bearings, variations of kurtosis values are investigated in terms of two different data processing techniques: minimum entropy deconvolution (MED), and the Teager-Kaiser Energy Operator (TKEO). MED and the TKEO are employed to qualitatively enhance the discrimination of defect-induced repeating peaks on bearing vibration data with measurement noise. Given the perspective of the execution sequence of MED and the TKEO, the study found that the kurtosis sensitivity towards a defect on bearings could be highly improved. Also, the vibration signal from both healthy and damaged bearings is decomposed into multiple intrinsic mode functions (IMFs), through empirical mode decomposition (EMD). The weight vectors of IMFs become design variables for a genetic algorithm (GA). The weights of each IMF can be optimized through the genetic algorithm, to enhance the sensitivity of kurtosis on damaged bearing signals. Experimental results show that the EMD-GA approach successfully improved the resolution of detectability between a roller bearing with defect, and an intact system.

The Light Cupula Phenomenon: A Scoping Review.

Direction-changing positional nystagmus (DCPN), which refers to the change in the direction of nystagmus with different head positions, is a well-known characteristic of horizontal semicircular canal BPPV. The supine head roll test is commonly used to diagnose horizontal canal BPPV. However, persistent geotropic DCPN observed during this test cannot be explained by the conventional explanations of canalolithiasis or cupulolithiasis. To account for this unique nystagmus, the concept of a "light cupula" has been recently introduced. In this review, we provide an overview of the historical background, clinical features and diagnostic methods, proposed mechanisms, and treatment strategies associated with the light cupula phenomenon based on the available literature to date.

Spontaneous Nystagmus in Patients With Posterior Semicircular Canal Benign Paroxysmal Positional Vertigo.

OBJECTIVE: This study aimed to investigate the incidence of spontaneous nystagmus (SN) in posterior semicircular canal (PSCC) benign paroxysmal positional vertigo (BPPV) and its effect on treatment outcomes. STUDY DESIGN: Retrospective case series. SETTING: Tertiary referral center. METHODS: This study included 50 patients with idiopathic unilateral PSCC BPPV between July 2021 and May 2022. The presence of SN was investigated, and the results of the bithermal caloric test and video head impulse test (vHIT) were compared. RESULTS: SN was observed in 13 (26%) of the 50 patients presenting PSCC BPPV. The direction of SN was mainly unidirectional and horizontal in 12 of the 13 patients with a slow-phase velocity ranging from 2 to 4°/s. One patient presented an upbeating torsional SN at the initial evaluation. The mean vHIT gain of the PSCC on the affected side was significantly lower in patients with SN than those without SN (p = .004, Mann-Whitney U test). The proportion of patients who recovered within 2 sessions of the repositioning maneuver was significantly higher in those without SN than that in those with SN (p < .001, Fisher's exact test). CONCLUSION: This study demonstrated that the treatment outcomes of PSCC BPPV were significantly worse in patients with SN than those without SN. Examining the presence of SN in patients with PSCC BPPV may be helpful in counseling the patients on prognosis, and it is expected that more sessions of canalith repositioning maneuver may be required to treat PSCC BPPV in patients with SN than those without SN.

Cerebellopontine angle tumor presenting as acute audiovestibular syndrome.

BACKGROUND: Acute audiovestibular deficits may be a harbinger of vestibular schwannoma (VS). OBJECTIVE: To investigate clinical and laboratory features of 25 consecutive patients with VS presenting with acute audiovestibular deficits. METHODS: A symptomatic combination of acute audiovestibular deficits was investigated. Audiometric and vestibular function tests, and internal auditory canal magnetic resonance imaging (IAC MRI) results were evaluated. RESULTS: Varying combinations of symptoms may develop in VS patients with acute audiovestibular deficits, of whom sudden hearing loss (HL) without acute vertigo or acute facial nerve palsy (FNP) was most common. The most common audiometric configuration was high-tone hearing loss, and no patient showed low-tone hearing loss. IAC MRI demonstrated that the tumor had an intracanalicular portion and attachment to the bony IAC wall in all patients and widened the IAC wall in some patients. CONCLUSION: Different symptomatic combinations of acute audiovestibular deficits may develop in patients with VS. Awareness about the possibility of VS as a cause of sudden HL, acute vertigo, and acute FNP, as well as subsequent IAC MRI scanning is vital to earlier diagnosis of VS in these patients.