Noninvasive measurement of tear film break-up time in eyes with high-water-content contact lenses

　Objective: To evaluate changes in tear dynamics under soft contact lenses (SCLs) by measuring the noninvasive Keratograph break-up time (NIKBUT) in subjects wearing SCLs.　Methods: The study included 24 eyes of 12 subjects (10 women and 2 men; age range, 19-38 years) with experience wearing contact lenses and without ocular surface disease except for a refractive error. An infrared video-topographer was used to measure the NIKBUTs with and without high-water-content contact lens. The subjects were asked to grade their subjective feeling of dehydration on a scale of 0 to 3, with 0 indicating no dehydration and 3 indicating maximal dehydration.　Results: The eyes were divided into two groups: group A comprising 16 eyes that showed a significant decrease (P < 0.05) in the NIKBUTs with SCLs, and group B comprising eight eyes in which the NIKBUTs remained unchanged. The NIKBUTs without SCLs were significantly longer (P < 0.001) in group A than in group B. The subjective feelings of dehydration decreased significantly (P < 0.001) among subjects with SCLs in group B, whereas the subjective feelings remained unchanged among subjects in group A.　Conclusions: The NIKBUTs became relatively shorter with SCLs regardless of the basal NIKBUT of a bare eye. The changes in the NIKBUTs with SCLs could be classified into two groups. These findings offer new insights into the mechanism underlying SCL-induced complications

commerciallyA novel cultivated oral mucosal epithelial cell sheet transplantation (COMET) method using a commercially available regenerative product sheet originating from human ectopic autologous tissue

BACKGROUND: We report the first case of cultivated oral mucosal epithelial cell sheet transplantation (COMET) using a commercial product from a different human tissue. CASE PRESENTATION: An 80-year-old man presented with bilateral blurred vision secondary to corneal limbal stem cell deficiency (LSCD) caused by bilateral ocular cicatricial pemphigoid (OCP). The patient first noted the loss of visual acuity in his left eye at 56 years of age. He was referred to a local hospital and was diagnosed with uveitis. He was administered ten bilateral ocular sub-tenon injections of triamcinolone acetonide. The uveitis progressed to cataracts, requiring bilateral phacoemulsification with intraocular lens implantation. Although the uveitis gradually improved, his visual acuity deteriorated due to the LSCD caused by OCP. At 61 years of age, amniotic membrane transplantation was performed in the left eye. However, its effect was limited, and OCP continued progressing in both eyes. On referral to our hospital, he had only light perception on visual acuity testing. The COMET was performed in the right eye using a commercially available product sheet (Oculal®; Japan Tissue Engineering Co., Ltd., Aichi, Japan). Ten days postoperatively, epithelialization was observed in the cornea and conjunctiva. His visual acuity improved to 20/1000. The patient was discharged on the same day. CONCLUSION: This is the first report on the use of a commercially available ectopic product (Japan Tissue Engineering Co., Ltd., Aichi, Japan) originating from different human tissues (oral mucosa) for COMET. COMET may be a radical treatment for corneal LSCD

Neural coding of syntactic structure in learned vocalizations in the songbird.

鳥類の音声における文法規則の神経コーディングの解明. 京都大学プレスリリース. 2011-7-15.Although vocal signals including human languages are composed of a finite number of acoustic elements, complex and diverse vocal patterns can be created from combinations of these elements, linked together by syntactic rules. To enable such syntactic vocal behaviors, neural systems must extract the sequence patterns from auditory information and establish syntactic rules to generate motor commands for vocal organs. However, the neural basis of syntactic processing of learned vocal signals remains largely unknown. Here we report that the basal ganglia projecting premotor neurons (HVC(X) neurons) in Bengalese finches represent syntactic rules that generate variable song sequences. When vocalizing an alternative transition segment between song elements called syllables, sparse burst spikes of HVC(X) neurons code the identity of a specific syllable type or a specific transition direction among the alternative trajectories. When vocalizing a variable repetition sequence of the same syllable, HVC(X) neurons not only signal the initiation and termination of the repetition sequence but also indicate the progress and state-of-completeness of the repetition. These different types of syntactic information are frequently integrated within the activity of single HVC(X) neurons, suggesting that syntactic attributes of the individual neurons are not programmed as a basic cellular subtype in advance but acquired in the course of vocal learning and maturation. Furthermore, some auditory-vocal mirroring type HVC(X) neurons display transition selectivity in the auditory phase, much as they do in the vocal phase, suggesting that these songbirds may extract syntactic rules from auditory experience and apply them to form their own vocal behaviors

Severe chemical corneal injury from hexavalent chromium exposure: a case report

AbstractEye exposure to hexavalent chromium (Cr(VI)) acid can cause blindness. A 42-year-old man working in a plating operation presented to the emergency department following a workplace incident. He had unintentionally fallen into a tank containing a mixture of 25% Cr(VI) and sulfuric acid (2.0 g/L) at a temperature of approximately 40 °C. The tank dimensions tank were 8 (depth) × 4 (width) × 3 (length) meters. A colleague rescued him from the tank, and he underwent a full body wash at the worksite. Emergency services adequately flushed both eyes with a 0.9% saline solution. He had significant corneal injury; however, no other significant injuries occurred. Upon presentation at the emergency department, the patient underwent a whole-body shower, and both eyes were flushed with 0.9% saline solution. As a treatment for acute chromium poisoning, he received dimercaprol and ascorbic acid. Additionally, he received eye drops for chemical corneal injury. The patient later underwent bilateral corneal transplants for chemical corneal injury but remained nearly blind. We describe a case of severe chemical corneal injury with limbal stem cell deficiency, leading to blindness due to Cr (VI) acid exposure

Relationship between Full-Thickness Macular Hole Onset and Posterior Vitreous Detachment

Purpose: To evaluate the relationship between full-thickness macular hole (FTMH) onset and perifoveal posterior vitreous detachment using OCT data. Design: Retrospective study. Participants: A total of 742 patients with FTMH or impending macular hole (MH) in ≥ 1 eye, as determined by ophthalmoscopy and OCT. Methods: Macular holes were staged using OCT results. Patients with the posterior vitreous membrane clearly detected in the OCT images and vitreoretinal adhesion size ≤ 1500 μm—eyes with MH stages 1–3—were included in the study. The contralateral eyes were also included in the analyses if they showed the focal type of vitreomacular adhesion (VMA) (i.e., vitreoretinal adhesion ≤ 1500 μm). The distance between the posterior vitreous membrane and the surface of the retina was defined as the posterior vitreous separation height (PVSH). Using the OCT images, PVSHs of each eye in 4 directions (nasal, temporal, superior, and inferior) at 1 mm from the center of the MH or fovea were calculated. Main Outcome Measures: The main outcome measures were PVSHs according to the MH stage and VMA, the relationship of the foveal inner tear with PVSH, and the likelihood of a foveal inner tear based on the direction. Results: The PVSH trends in each of the 4 directions were as follows: VMA < MH stage 1 = MH stage 2 < MH stage 3. Initial MH stage 2 (onset of FTMH) was defined as the presence of a gap in only 1 of the 4 directions from the center of the MH. With increased PVSH, the likelihood of a gap increased (P = 0.002), and a temporal gap was more likely to occur than a nasal gap (P = 0.002). Conclusions: At FTMH onset, a foveal inner tear likely appears on the temporal side or the side showing a high PVSH value. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article