Relationship between structural and functional changes in glaucomatous eyes: a multifocal electroretinogram study.

BACKGROUND: The nasal to temporal amplitudes ratio (N/T) of multifocal electroretinography (mfERG) scans measured within 5° of the macula can be used to detect glaucomatous change. The photopic negative response (PhNR) of mfERG elicited by a circular stimulus centered on the fovea was significantly reduced in eyes with glaucoma. The PhNR to B-wave ratio (PhNR/B) is the optimal measure of the PhNR. However, clinical superiority for evaluating glaucoma patients has not been determined between N/T and PhNR/B yet. METHODS: For morphological assessments, ganglion cell complex (GCC) in six regions and the average were measured by optical coherence tomography (OCT). For functional assessment, Humphrey visual fields (VF) with mean sensitivities (MT) and mfERG scans with parameters of N/T and the multifocal photopic negative response to B-wave ratio (mfPhNR/B) were measured. Sixty-nine eyes of 44 glaucoma patients were included and correlations between mfERG parameters and OCT or VF parameters were evaluated. RESULTS: The mean age of patients was 59.4 years. The mean deviation for all eyes obtained with the VF 30-2 and VF 10-2 was - 7.00 and - 6.31 dB, respectively. Significant correlations between GCC thickness or VF parameter and the N/T were found, especially in the inferior and inforotemporal retinal areas corresponding to superior and superonasal VF sectors (GCC vs N/T; coefficient = - 7.916 and - 7.857, and MT vs N/T; coefficient = - 4.302 and - 4.437, in the inferior and inforotemporal retinal areas, respectively, all p values < 0.05). However, similar associations were not obtained between mfPhNR/B and OCT or VF parameters. The mfPhNR/B only in the inferotemporal sector was significantly correlated with the average thickness of GCC (coefficient = 4.823, P = 0.012). CONCLUSIONS: The N/T was correlated with GCC and VF in more numbers of measurement areas than the mfPhNR/B in the current study, however, a future study modifying the stimuli and amplitudes to obtain the spatial correspondence to OCT and VF measurement will be required to evaluate the value of mfERG.

Evaluating the existence and benefit of major histocompatibility complex-based mate choice in an isolated owl population.

How mate preferences evolve in the first place has been a major conundrum for sexual selection. Some hypotheses explaining this assume fitness benefit derived from subsequent generations. Major histocompatibility complex (MHC)-based mate choice is a representative example of the mate choice that is associated with such trans-generational mechanisms. To provide evidences for fitness benefit of MHC-based mate choice, previous studies assessed the association between own MHC genotype and own fitness components. However, the association between MHC-based mate choice in the parental generation and fitness components in the resultant offspring generation has only rarely been measured in wild populations. Focusing on the isolated population of the monogamous Ryukyu Scops Owl (Otus elegans interpositus) on Minami-daito Island, Japan, we found evidence of MHC-based mate choice. However, we found no evidence of MHC-based mate choice increasing own reproductive success or offspring survival. This is a rare case study that directly examines the existence of the trans-generational indirect benefit of MHC-based mate choice for genetic compatibility from trans-generational data in a wild bird population. By investigating the fitness benefits of mate choice, this study serves to facilitate our understanding of the evolution of MHC-based mate choice.

The long-term outcome of trabeculotomy: comparison with filtering surgery in Japan.

BACKGROUND: To investigate the long-term outcome of trabeculotomy and to compare it with that of trabeculectomy. METHODS: We retrospectively reviewed the medical records of patients who had undergone standalone trabeculotomy. Inclusion criteria included a follow-up period of at least 6 years, availability of reliable static visual field results, etc. Age- and preoperative intraocular pressure -matched trabeculectomy cases served as controls. A Kaplan-Meier analysis was employed as a measure of surgical success. Additional clinical factors were also analyzed. RESULTS: Twenty-five eyes of 25 trabeculotomy patients and 20 eyes of 20 trabeculectomy patients with a mean postoperative follow-up period of 8.0 years were selected. The Kaplan-Meier analysis estimated that the success probability defined as intraocular pressure < 16 mmHg was 44.0 ± 9.9% and 75.0 ± 9.7% at 6 years for trabeculotomy and trabeculectomy, respectively. The final mean deviation significantly progressed in trabeculotomy cases in Central 30-2 programs of the Humphrey Field Analyzer (P = 0.025). Patient characteristics and postoperative clinical data were analyzed by Mann-Whitney's U test and Wilcoxon signed-rank test. CONCLUSIONS: While trabeculotomy was inferior to trabeculectomy in terms of intraocular pressure control and visual field stability in our series, surgical indications should always be determined on an individual basis, pending further research.

The 5-year incidence of bleb-related infection and its risk factors after filtering surgeries with adjunctive mitomycin C: collaborative bleb-related infection incidence and treatment study 2.

PURPOSE: To report the 5-year incidence of bleb-related infection after mitomycin C-augmented glaucoma filtering surgery and to investigate the risk factors for infections. DESIGN: Prospective, observational cohort study. PARTICIPANTS: A total of 1098 eyes of 1098 glaucoma patients who had undergone mitomycin C-augmented trabeculectomy or trabeculectomy combined with phacoemulsification and intraocular lens implantation performed at 34 clinical centers. METHODS: Patients were followed up at 6-month intervals for 5 years, with special attention given to bleb-related infections. The follow-up data were analyzed via Kaplan-Meier survival analysis and the Cox proportional hazards model. MAIN OUTCOME MEASURES: Incidence of bleb-related infection over 5 years and risk factors for infections. RESULTS: Of the 1098 eyes, a bleb-related infection developed in 21 eyes. Kaplan-Meier survival analysis revealed that the incidence of bleb-related infection was 2.2±0.5% (cumulative incidence ± standard error) at the 5-year follow-up for all cases, whereas it was 7.9±3.1% and 1.7±0.4% for cases with and without a history of bleb leakage, respectively (P = 0.000, log-rank test). When only eyes with a well-functioning bleb were counted, it was 3.9±1.0%. No differences were found between the trabeculectomy cases and the combined surgery cases (P = 0.398, log-rank test) or between cases with a fornix-based flap and those with a limbal-based flap (P = 0.651, log-rank test). The Cox model revealed that a history of bleb leakage and younger age were risk factors for infections. CONCLUSIONS: The 5-year cumulative incidence of bleb-related infection was 2.2±0.5% in eyes treated with mitomycin C-augmented trabeculectomy or trabeculectomy combined with phacoemulsification and intraocular lens implantation in our prospective, multicenter study. Bleb leakage and younger age were the main risk factors for infections.

Case of recurrence of spiradenoma in palpebral conjunctiva.

BACKGROUND: To report a rare case of a recurrence of spiradenoma that developed in the upper eyelid. CASE PRESENTATION: A 49-year-old woman who had a second recurrence of a tumor in the right palpebral conjunctiva underwent local resection of the lesion with adjunctive cryotherapy to the surgical site. The tumor consisted of smooth, round to oval nodular lesions approximately 1-3 mm in size with enlarged blood vessels. Histopathologically, the solid and well-circumscribed nodule was located beneath the conjunctival epithelium. It was composed of cells with slightly basophilic-to-clear cytoplasm and round-to-oval nuclei arranged in a trabecular pattern. Periodic acid-Schiff stain was positive in the cytoplasm, and the staining disappeared after digesting by diastase. Many cells in mitosis were observed throughout the tumor but no necrotic cells. Immunohistochemistry showed that the Ki-67 labeling index was 12%. From these findings, we diagnosed this tumor as a recurrence of the spiradenoma. There has been no recurrence and no signs of malignancy in the 6 months after the surgical excision. CONCLUSION: Our findings indicate that a spiradenoma should be completely excised surgically because of malignant transformation after repeated recurrences.

Dosimetric impact of gold markers implanted closely to lung tumors: a Monte Carlo simulation.

We are developing an innovative dynamic tumor tracking irradiation technique using gold markers implanted around a tumor as a surrogate signal, a real-time marker detection system, and a gimbaled X-ray head in the Vero4DRT. The gold markers implanted in a normal organ will produce uncertainty in the dose calculation during treatment planning because the photon mass attenuation coefficient of a gold marker is much larger than that of normal tissue. The purpose of this study was to simulate the dose variation near the gold markers in a lung irradiated by a photon beam using the Monte Carlo method. First, the single-beam and the opposing-beam geometries were simulated using both water and lung phantoms. Subsequently, the relative dose profiles were calculated using a stereotactic body radiotherapy (SBRT) treatment plan for a lung cancer patient having gold markers along the anterior-posterior (AP) and right-left (RL) directions. For the single beam, the dose at the gold marker-phantom interface laterally along the perpendicular to the beam axis increased by a factor of 1.35 in the water phantom and 1.58 in the lung phantom, respectively. Furthermore, the entrance dose at the interface along the beam axis increased by a factor of 1.63 in the water phantom and 1.91 in the lung phantom, while the exit dose increased by a factor of 1.00 in the water phantom and 1.12 in the lung phantom, respectively. On the other hand, both dose escalations and dose de-escalations were canceled by each beam for opposing portal beams with the same beam weight. For SBRT patient data, the dose at the gold marker edge located in the tumor increased by a factor of 1.30 in both AP and RL directions. In clinical cases, dose escalations were observed at the small area where the distance between a gold marker and the lung tumor was ≤ 5 mm, and it would be clinically negligible in multibeam treatments, although further investigation may be required.

Development of a dose verification system for Vero4DRT using Monte Carlo method.

Vero4DRT is an innovative image-guided radiotherapy system employing a C-band X-ray head with gimbal mechanics. The purposes of this study were to propose specific MC models of the linac head and multileaf collimator (MLC) for the Vero4DRT and to verify their accuracy. For a 6 MV photon beam delivered by the Vero4DRT, a simulation code was implemented using EGSnrc. The linac head model and the MLC model were simulated based on its specification. Next, the percent depth dose (PDD) and beam profiles at depths of 15, 100, and 200 mm were simulated under source-to-surface distance of 900 and 1000 mm. Field size was set to 150 × 150 mm2 at a depth of 100 mm. Each of the simulated dosimetric metrics was then compared with the corresponding measurements by a 0.125 cc ionization chamber. After that, intra- and interleaf leakage, tongue-and-groove, and rounded-leaf profiles were simulated for the static MLC model. Meanwhile, film measurements were performed using EDR2 films under similar conditions to simulation. The measurement for the rounded-leaf profile was performed using the water phantom and the ionization chamber. The leaf physical density and abutting leaf gap were adjusted to obtain good agreement between the simulated intra- and interleaf leakage profiles and measurements. For the MLC model in step-and-shoot cases, a pyramid and a prostate IMRT field were simulated, while film measurements were performed using EDR2. For the linac head, exclusive of MLC, the difference in PDD was < 1.0% after the buildup region. The simulated beam profiles agreed to within 1.3% at each depth. The MLC model has been shown to reproduce dose measurements within 2.5% for static tests. The MLC is made of tungsten alloy with a purity of 95%. The leaf gap of 0.015 cm and the MLC physical density of 18.0 g/ cm3, which provided the best agreement between the simulated and measured leaf leakage, were assigned to our MC model. As a result, the simulated step-and-shoot IMRT dose distributions agreed with the film measurements to within 3.3%, with exception of the penumbra region. We have developed specific MC models of the linac head and the MLC in the Vero4DRT system. The results have demonstrated that our MC models have high accuracy. 

Possible Shifts in the Genetic Diversity of Red-crowned Cranes (Grus japonensis) in Hokkaido, Japan: Indications of Continental Gene Flow.

Red-crowned cranes (Grus japonensis) consist of two distinct groups: the continental population and the island population. The island population, localized in Hokkaido, Japan, exhibits very low genetic diversity due to its rapid recovery from the brink of extinction. Our previous research in 2018 highlighted a possible mating between a male from the continental population, with the Gj5 haplotype, and a female from the island population, with the Gj2 haplotype, at Hitominuma Sawmp shore in northern Hokkaido. The present study attempted to unravel the distribution of their offspring by examining the major histocompatibility complex (MHC) of this mixed breeding pair compared with samples collected from cranes in northern and southeastern Hokkaido between 2008 and 2022. The analysis identified 55 MHC types, including 10 known types in a dataset of 89 crane samples, based on amino acid sequences. A total of 58 MHC types were recognized, based on nucleotide sequences, as there were many cases in which the same amino acid sequence had different nucleotide sequences. The five DNA types of MHC in the Hitominuma Swamp male were predominantly identified in eight cranes from northern Hokkaido and one chick from southeastern Hokkaido. In addition, population genetic analysis, based on insertion/deletion (InDel) polymorphisms, indicates distinct population differentiation between the northern and southeastern regions of Hokkaido. These results suggest that genetic contributions from the continental red-crowned crane population have already been integrated into the Hokkaido populations, with a more pronounced influence in northern Hokkaido.

Intraocular penetration of intravenous micafungin in inflamed human eyes.

Eight eyes of 7 patients with fungal disease received intravenous injections of 150 to 300 mg micafungin, and samples of blood, cornea, retina-choroid, aqueous humor, and vitreous humor were collected. The micafungin levels in all collected samples exceeded the MICs; however, the levels in the vitreous and aqueous humors were lower. Our findings suggest that intravenous micafungin should be given in combination with intravitreal antifungal agents after vitrectomy in severe cases of intraocular fungal diseases.

Case of endogenous endophthalmitis caused by Klebsiella pneumoniae with magA and rmpA genes in an immunocompetent patient.

We report a case of endogenous endophthalmitis caused by Klebsiella pneumoniae in an immunocompetent patient. A 73-year-old man with acute epididymitis who had no history of diabetes mellitus developed endogenous endophthalmitis. The patient underwent anterior vitrectomy and intracapsular cataract extraction with intravitreal injections of both vancomycin and ceftazidime. After the surgery, he was treated with topical and intravenous antibiotics; however, the left eye perforated and was enucleated. Culture from vitreous biopsy specimens grew as K. pneumoniae, which was positive for both magA and rmpA. K. pneumoniae should be considered as a pathogen that can cause severe endogenous endophthalmitis in patients with urinary tract infection. The severity of the disease may be related to the virulence genes.

Effect of audio instruction on tracking errors using a four-dimensional image-guided radiotherapy system.

The Vero4DRT (MHI-TM2000) is capable of performing X-ray image-based tracking (X-ray Tracking) that directly tracks the target or fiducial markers under continuous kV X-ray imaging. Previously, we have shown that irregular respiratory patterns increased X-ray Tracking errors. Thus, we assumed that audio instruction, which generally improves the periodicity of respiration, should reduce tracking errors. The purpose of this study was to assess the effect of audio instruction on X-ray Tracking errors. Anterior-posterior abdominal skin-surface displacements obtained from ten lung cancer patients under free breathing and simple audio instruction were used as an alternative to tumor motion in the superior-inferior direction. First, a sequential predictive model based on the Levinson-Durbin algorithm was created to estimate the future three-dimensional (3D) target position under continuous kV X-ray imaging while moving a steel ball target of 9.5 mm in diameter. After creating the predictive model, the future 3D target position was sequentially calculated from the current and past 3D target positions based on the predictive model every 70 ms under continuous kV X-ray imaging. Simultaneously, the system controller of the Vero4DRT calculated the corresponding pan and tilt rotational angles of the gimbaled X-ray head, which then adjusted its orientation to the target. The calculated and current rotational angles of the gimbaled X-ray head were recorded every 5 ms. The target position measured by the laser displacement gauge was synchronously recorded every 10 msec. Total tracking system errors (ET) were compared between free breathing and audio instruction. Audio instruction significantly improved breathing regularity (p < 0.01). The mean ± standard deviation of the 95th percentile of ET (E95T ) was 1.7 ± 0.5 mm (range: 1.1-2.6mm) under free breathing (E95T,FB) and 1.9 ± 0.5 mm (range: 1.2-2.7 mm) under audio instruction (E95T,AI). E95T,AI was larger than E95T,FB for five patients; no significant difference was found between E95T,FB and E95T,AI (p = 0.21). Correlation analysis revealed that the rapid respiratory velocity significantly increased E95T. Although audio instruction improved breathing regularity, it also increased the respiratory velocity, which did not necessarily reduce tracking errors.

Analysis of Crop Consumption Using Scatological Samples from the Red-Crowned Crane Grus japonensis in Eastern Hokkaido, Japan.

Total DNA extracts from the intestinal contents of 60 flying red-crowned cranes (juveniles, subadults and adults) found dead in 2006-2021, and the feces of 25 chicks collected in June and July of 2016-2018, were used for PCR reactions with primers specific for 16 crops, followed by high-throughput sequencing. The most predominant crop detected was corn in adult and subadult cranes (61.7%). Other grains (barley, wheat, soybean) (5.0-8.3%) and vegetables (tomatoes, Chinese cabbage, etc.) (1.7-6.7%) were also detected in flying cranes. Surprisingly, some of the detected crops were not grown in the Kushiro and Nemuro regions. There was no significant difference in crop intake status in winter and that in other seasons for most of the crops. Corn (28.0%), soybeans (8.0%), wheat and beet (4.0%) were detected in crane chicks in summer, though the detection rates were generally lower than those in flying cranes. Alfalfa, which is not grown in eastern Hokkaido but is used in some cattle feed, was detected in some cranes. Rice, buckwheat, adzuki beans, common beans, potatoes and carrots were not detected at any life stage, indicating the preferences of red-crowned cranes. The results suggest that red-crowned cranes in Hokkaido are dependent on dairy farmers for their feed supply.

Positional accuracy of novel x-ray-image-based dynamic tumor-tracking irradiation using a gimbaled MV x-ray head of a Vero4DRT (MHI-TM2000).

PURPOSE: To verify the positional accuracy of a novel x-ray-image-based dynamic tumor-tracking (DTT) irradiation technique using the gimbaled MV x-ray head of a Vero4DRT (MHI-TM2000). METHODS: Verification of the x-ray-image-based DTT was performed using three components: a three-dimensional moving phantom with a steel ball target, a laser displacement gauge, and an orthogonal kV x-ray imaging subsystem with a gimbaled MV x-ray head and the system controller of the Vero4DRT. The moving phantom was driven based on seven periodic patterns [peak-to-peak amplitude (A): 20-40 mm, breathing period (T): 2-5 s] and 15 patients' aperiodic respiratory patterns (A: 6.5-22.9 mm, T: 1.9-5.8 s). The target position was detected in real time with the orthogonal kV x-ray imaging subsystem using the stereo vision technique. Subsequently, the Vero4DRT predicted the next position of the target, and then the gimbaled MV x-ray head tracked the corresponding orientation of the target. The displacements of the target were measured synchronously using the laser displacement gauge. The difference between the target positions predicted by the Vero4DRT and those measured by the laser displacement gauge was computed as the prediction error (E(P)), and the difference between the target positions tracked by the gimbaled MV x-ray head and predicted target positions was computed as the mechanical error (E(M)). Total tracking system error (E(T)) was defined as the difference between the tracked and measured target positions. RESULTS: The root mean squares (RMSs) of E(P), E(M), and E(T) were up to 0.8, 0.3, and 0.7 mm, respectively, for the periodic patterns. Regarding the aperiodic patterns, the median RMSs of E(P), E(M), and E(T) were 1.2 (range, 0.9-1.8) mm, 0.1 (range, 0.1-0.5) mm, and 1.2 (range, 0.9-1.8) mm, respectively. From the results of principal component analysis, tracking efficiency, defined as the ratio of twice the RMS of E(T) to A, was improved for patients with high respiratory function (R = 0.91; p < 0.01). CONCLUSIONS: The present study demonstrated that the Vero4DRT is capable of high-accuracy x-ray-image-based DTT. E(T) was caused primarily by E(P), and E(M) was negligible. Furthermore, principal component analysis showed that tracking efficiency could be improved with this system, especially for patients with high respiratory function.

Optimization of the x-ray monitoring angle for creating a correlation model between internal and external respiratory signals.

PURPOSE: To perform dynamic tumor tracking irradiation with the Vero4DRT (MHI-TM2000), a correlation model [four dimensional (4D) model] between the displacement of infrared markers on the abdominal wall and the three-dimensional position of a tumor indicated by a minimum of three implanted gold markers is required. However, the gold markers cannot be detected successfully on fluoroscopic images under the following situations: (1) overlapping of the gold markers; and (2) a low intensity ratio of the gold marker to its surroundings. In the present study, the authors proposed a method to readily determine the optimal x-ray monitoring angle for creating a 4D model utilizing computed tomography (CT) images. METHODS: The Vero4DRT mounting two orthogonal kV x-ray imaging subsystems can separately rotate the gantry along an O-shaped guide-lane and the O-ring along its vertical axis. The optimal x-ray monitoring angle was determined on CT images by minimizing the root-sum-square of water equivalent path lengths (WEPLs) on the orthogonal lines passing all of the gold markers while rotating the O-ring and the gantry. The x-ray monitoring angles at which the distances between the gold markers were within 5 mm at the isocenter level were excluded to prevent false detection of the gold markers in consideration of respiratory motions. First, the relationship between the WEPLs (unit: mm) and the intensity ratios of the gold markers was examined to assess the validity of our proposed method. Second, our proposed method was applied to the 4D-CT images at the end-expiration phase for 11 lung cancer patients who had four to five gold markers. To prove the necessity of the x-ray monitoring angle optimization, the intensity ratios of the least visible markers (minimum intensity ratios) that were estimated from the WEPLs were compared under the following conditions: the optimal x-ray monitoring angle and the angles used for setup verification. Additionally, the intra- and interfractional variations in the intensity ratio were examined from the optimal x-ray monitoring angle. RESULTS: A negative strong correlation was observed between the WEPL (x) and the intensity ratio (y) (y = 6.57 exp[-0.0125x] + 1, R = -0.88 [95% confidence interval: -0.85 to -0.90], p < 0.01). Our proposed method effectively avoided having the x-ray beam pass through high-density structures, although there were large interpatient variations in the optimal x-ray monitoring angle because of the geometric arrangement between the gold markers and the anatomical structures. The minimum intensity ratios that were estimated from the WEPLs at the optimal x-ray monitoring angle ranged from 1.43 to 2.48, which was an average of 1.27 times (range, 1.02-1.66) higher than the angles used for setup verification. The maximum intra- and interfractional decreases in the intensity ratio were 0.23 and 0.17, respectively. CONCLUSIONS: The authors demonstrated that the optimal x-ray monitoring angle for creating a 4D model can improve the visibility of gold markers.

Assessment of macular function of glaucomatous eyes by multifocal electroretinograms.

PURPOSE: To determine whether significant correlations existed between the morphological and functional parameters of the macular region of eyes with open-angle glaucoma (OAG). METHODS: Forty eyes of 40 OAG patients were studied. The morphological parameters were obtained by optical coherence tomography (OCT), and the functional parameters were acquired by automated Humphrey Field Analyzer (HFA) and multifocal electroretinograms (mfERGs). All of the tests were performed within 6 months of each other. The retinal thickness was determined by OCT in the nine Early Treatment of Diabetic Retinopathy Study (ETDRS) sectors of the macula, the fovea, and the four quadrants of the inner and an outer ring. The amplitudes of the second-order kernel responses of the mfERGs in the central 5° including the amplitude ratio of the nasal to temporal hemispheres (N/T amplitude ratio) were analyzed. The total mean deviation of the HFA corresponding to each OCT region was measured. The correlation between the different parameters was determined by coefficients of correlation and linear regression analyses. RESULTS: The N/T amplitude ratio of the second-order kernel responses of the mfERGs was significantly correlated with the retinal thickness in the inferior quadrant (r = -0.44; P = 0.004). There was a significant correlation between the N/T amplitude ratio and the threshold in the superior quadrant measured by the HFA Central 10-2 program (r = -0.40; P = 0.011) and also between the N/T amplitude ratio and the total deviation in the superior quadrant (r = -0.40; P = 0.010). There were significant correlations between the inferior retinal thickness and the average threshold and the TD in superior (r = 0.70, P < 0.001; r = 0.692, P < 0.001, respectively), nasal (r = 0.53, P < 0.001; r = 0.53, P < 0.001, respectively), and temporal (r = 0.46, P = 0.003; r = 0.44, P = 0.004, respectively) quadrants. CONCLUSIONS: Functional glaucomatous changes determined by mfERGs and perimetry are significantly correlated with the morphological changes determined by OCT.

Effects of trabeculectomy on posture-induced intraocular pressure changes over time.

INTRODUCTION: To determine whether trabeculectomy affects postural-induced changes in intraocular pressure (IOP), and whether it is maintained. METHODS: Thirty-six eyes of 36 patients with open-angle glaucoma who were scheduled for their initial trabeculectomy with adjunctive mitomycin C were prospectively examined. The IOP was measured in the sitting and the lateral decubitus position with an ICare rebound tonometer before, and 1, 3, and 12 months after trabeculectomy. RESULTS: Twenty-nine eyes of 29 patients completed this study. The mean baseline IOP measured with the ICare tonometer was 17.4 ± 4.9 mmHg in the sitting position and 21.3 ± 5.6 mmHg in the lateral decubitus position (p < 0.001). This postural IOP difference, +3.9 mmHg, was reduced to +1.3 ± 1.7 mmHg at 1 month and to +0.8 ± 1.5 mmHg at 3 months after the trabeculectomy (p < 0.001 and p = 0.004 respectively). This decrease in the degree of posture-dependent IOP change was maintained at +1.7 ± 2.2 mmHg at 1 year postoperatively (p < 0.001). In three cases, the postural IOP changes returned to the baseline level, and all three had a failed bleb. CONCLUSIONS: Our results indicate that trabeculectomy not only reduces the IOP but also reduces the degree of posture-induced changes in the IOP. Our findings also speculate that measuring the postural IOP changes after trabeculectomy might provide a clue on the functioning of a filtering bleb.

Randomized crossover study of latanoprost and travoprost in eyes with open-angle glaucoma.

INTRODUCTION: To compare the intraocular pressure (IOP)-lowering effects of 0.005% latanoprost to that of 0.004% travoprost in eyes with open-angle glaucoma (OAG). METHODS: Forty-two patients with OAG who received either latanoprost or travoprost every evening for 12 weeks, and then switched to the other medication for another 12 weeks. The IOP measurements were made with a Goldmann applanation tonometer (GAT) at the baseline, and at 1, 3, 4, and 6 months after the treatment. The IOP at the untreated baseline and at the end of each treatment period was measured at 10:00, 12:00, and 16:00 hours. The central corneal thickness (CCT) was measured at each visit using an ultrasonic pachymeter. RESULTS: The mean baseline IOP was 13.9 ± 2.5 mmHg, and the CCT was 536.7 ± 30.5 µm. Latanoprost reduced the IOP by 2.5 ± 1.7 mmHg and travoprost by 2.6 ± 1.5 mmHg from the baseline (p = 0.6807). The CCT decreased significantly to 531.9 ± 30.3 at 3 months (p = 0.0160) and to 529.4 ± 30.5 µm at 6 months (p = 0.0002) after the therapy. The decrease was significantly greater in eyes after travoprost (p = 0.0049). CONCLUSIONS: Travoprost has similar effect as latanoprost in reducing the IOP in glaucoma patients with relatively low IOPs. The use of prostaglandin analogs can decrease the CCT, and this change should be considered when the IOPs obtained by GAT are analyzed.

Mate choice for body size leads to size assortative mating in the Ryukyu Scops Owl Otus elegans.

Understanding evolutionary phenomena that involve size assortative mating requires elucidating the generating mechanisms on which assortment is based. Although various mechanisms have been suggested, their relative importance may differ across taxonomic groups. Males selecting for large, fecund females combined with the dominance of large males in the competition for females has been suggested as a major mechanism in specific groups. However, raptors do not appear to conform to this, because the selection for smallness among males (assumed in a theory of reversed sexual size dimorphism) and the selection for largeness among males (assumed in the theory of size assortative mating) are in opposite directions. We studied the assortative mating during a long-term study of the Ryukyu Scops Owls Otus elegans interpositus. Significant assortative mating was found for culmen length (from the base to the tip of the bill) and wing length (from the bend of the wing to the tip of the longest primary). Statistical control of the spatial and temporal accessibility of potential mates did not affect the assortment. Males with short wings had slightly higher fitness components than those with long wings, and females settling early tended to have small wings. Considering that early-settling females can preferentially choose their mates, these results suggest that smaller females have an advantage when choosing smaller males with good reproductive performance. Improved flying and hunting ability of smaller individuals may be the background of choosing smaller individuals. We propose that, not passive process like similarity between individuals and their potential mates, but active mate choice for small individuals is an explanation for the assortative mating in this owl.

Conventional Gel Electrophoresis-Resolvable Insertion/Deletion Markers for Individual Identification and Analysis of Population Genetics in Red-Crowned Cranes in Eastern Hokkaido, Japan.

Red-crowned crane Grus japonensis is an endangered species in two separate populations: the mainland population in the Eurasian continent and the island population in eastern Hokkaido, Japan. We found 11 insertion/deletion (InDel) markers in the genome of the red-crowned crane and designed primer sets across these InDels that can be analyzed with conventional agarose gel electrophoresis. Sixty-six samples of whole blood and skeletal muscle obtained from red-crowned cranes, including 12 families in eastern Hokkaido from 1994 to 2021, showed different patterns in gel images of 11 InDel PCR reactions except for two pairs. The combined non-exclusion probability of the 11 markers indicates that individuals can be determined with a probability of 99.9%. In 39 non-relative chicks, the expected heterozygosity (He) was 0.316, suggesting low genetic diversity. This might not be caused by high levels of inbreeding since the average FIS was not significantly different from zero (0.095, p = 0.075). The results suggest that the 11 InDel primer sets can be used for fairly accurate individual identification as well as genetic population analyses in red-crowned cranes in the island population.

Positioning accuracy of a new image-guided radiotherapy system.

PURPOSE: To evaluate the accuracy of the patient-positioning function of a newly developed image-guided radiotherapy system, the MHI-TM2000 (Mitsubishi Heavy Industries, Ltd., Japan). METHODS: The isocenter positions prescribed by the lasers, MV treatment beam, and image guidance systems (kV X-ray image and kV-CBCT) were calculated using a cube phantom with a 10-mm-diameter steel ball fixed to the center of the phantom. Then, their location discrepancies were estimated. In addition, to verify the scale and orientation of the coordinate axes of the kV X-ray imaging system, positional measurements were repeated with the phantom placed at 50 mm off-isocenter along the vertical, longitudinal, and lateral directions, respectively. Further, image fusions of an anthropomorphic phantom image and the corresponding image translated by a pre-determined amount were performed. RESULTS: The isocenter alignment among the coordinate systems was coincident within 0.5 mm in translation for the vertical, longitudinal, and lateral axes, respectively. The geometrical errors at 50 mm off-isocenter for kV X-ray images and CBCT were within 0.2 mm and 1.0 mm, respectively. The image fusion errors were within 1.0 mm in translation and 1.0 degrees in rotation, respectively. No significant difference in the image fusion accuracy was observed between the chest and pelvis phantoms. CONCLUSIONS: The isocenter alignment among the coordinate systems was performed with high accuracy. Furthermore, the automatic image fusion function achieved sufficient patient positioning accuracy and precision for image-guided radiotherapy.