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Kirika Kanai, Yuro Igawa, Midori Tachibana, Yuji Yoshikawa, Takeshi Katsumoto, Masayuki Shibuya, Tatsukata Kawagoe, Jun Makita, Kei Shinoda Departments of Ophthalmology, Saitama Medical University, Faculty of Medicine, Saitama, 350-0495, JapanCorrespondence: Kei Shinoda, Departments of Ophthalmology, Saitama Medical University, Faculty of Medicine, 38 Moro-Hongo Moroyama-machi, Iruma-gun, Saitama, 350-0495, Japan, Tel +81-49-276-1250, Fax +81-49-295-8002, Email shinok@saitama-med.ac.jpPurpose: To determine the physiological status of the retina by electroretinography (ERG) using skin electrodes and the RETevalTM system in eyes that had undergone pars plana vitrectomy (PPV) with silicone oil (SO) tamponade. The vitrectomy was performed for a retinal detachment and proliferative diabetic retinopathy (PDR).Design: Retrospective case series.Methods: ERGs were recorded with the RETevalTM system (LKC Technologies Inc. Gaithersburg, MD; Welch Allyn, Inc. Skaneateles Falls, NY) from eight eyes with PDR before and after the SO removal. The amplitudes and implicit times of the a- and b-waves of the ERGs before the SO removal were compared to that after the SO removal.Results: ERGs were recordable in four eyes before and after the SO removal and the a- and b-amplitudes improved in three eyes and worsened in one eye after the SO removal. In the remaining four eyes, ERGs were non-recordable both before and after the SO removal.Conclusion: These results indicate that ERGs picked up by skin electrodes can be used to assess the physiology of the retina in eyes with a SO tamponade. The flat ERGs in the SO-filled eye indicated the presence of diffuse retinal damage which was confirmed by the flat ERGs after the SO removal.Plain Language Summary: There has been an increasing number of reports on evaluating the retinal function using electroretinography (ERG) with skin electrodes. The main advantage of this system is the ability to record ERGs with a skin electrode that does not touch the cornea and ocular surface. This reduces the risk of infection especially in the postoperative period and in clinical situations where infection is suspected. In addition, there have been only a few reports evaluating the function of the retina by ERG in SO-filled eyes.We recorded ERGs with the RETeval (LKC Technologies Inc. Gaithersburg, MD; Welch Allyn Inc. Skaneateles Falls, NY) device, a relatively new ERG recording system that uses skin electrodes and is less invasive. We recorded ERGs from eight SO-filled eyes with proliferative diabetic retinopathy (PDR). In 4 SO filled eyes, the amplitudes increased in three eyes after the SO removal. In the other four eyes, ERGs were non-recordable before and after the SO removal. These results suggest that the RETeval system that uses skin electrodes can be used to assess the retinal function in PDR eyes with a SO tamponade. We suggest that the absence of ERGs in the SO filled eyes was not due to the electrical non-conductive effects of SO but may indicate the presence of diffuse retinal damage which was confirmed after the SO removal.Keywords: electroretinogram, pars plana vitrectomy, proliferative diabetic retinopathy, silicone oil, skin electrode

Koki Sakata, Takeshi Katsumoto, Tomoyuki Kumagai, Kei Shinoda Department of Ophthalmology, Saitama Medical University, Saitama, JapanCorrespondence: Kei Shinoda, Department of Ophthalmology, Saitama Medical University, 38 Morohongo, Moroyama, Saitama, 350-0495, Japan, Tel +81-4-9276-1250, Fax +81-4-9295-8002, Email shinok@saitama-med.ac.jpPurpose: To determine whether 0.025% povidone-iodine (0.025% PI) in the irrigation solution during vitrectomy for endophthalmitis is safe.Methods: Two cases of bleb-associated endophthalmitis were treated with vitrectomy using 0.025% PI in the irrigation solution. The RETevel electroretinographic (ERG) system with skin electrodes was used to assess the physiology of the retina pre- and postoperatively.Case: Case 1 was a 46-year-old man who had atopic keratoconjunctivitis and underwent trabeculectomy with the creation of a bleb after there was a rise in the intraocular pressure. One month postoperatively, a mild filtering bleb-associated endophthalmitis developed, and the eye was treated with intravitreal and subconjunctival injections of vancomycin (VCM) and ceftazidime (CAZ). After three days, the fundus was not visible and B-mode echography showed an area of high brightness in the retina. Vitrectomy with irrigation with VCM and CAZ, and 0.025% PI was performed successfully. Pre- and postoperative ERGs showed an improvement in both the a- and b-wave amplitudes and the b/a ratio was stable at 2.0. Case 2 was a 63-year-old man who had undergone trabeculectomy for glaucoma. Five years later, the eye developed blebitis which was treated with topical and subconjunctival injections of VCM and CAZ. Three days later, vitreous opacities appeared and a high brightness area was seen in the B-mode echographic images. Vitrectomy with VCM and CAZ, and 0.025% PI irrigation was successfully performed. Comparisons of the pre- and postoperative ERGs found that the a- and b- wave amplitudes of the ERGs increased and the b/a ratio was stable at approximately 1.5.Conclusion: Vitrectomy with 0.025% PI irrigation is safe and ERG recordings with skin electrodes can be used to evaluate the pre- and postoperative retinal physiology safely.Plain Language Summary: We report our findings in two cases of bleb-related endophthalmitis that underwent pars plana vitrectomy (PPV) with irrigation with 0.025% povidone-iodine (PI)-Balanced Salt Solution (BSS) PLUS (Alcon Laboratories, Fort Worth, TX). The retinal function was evaluated by full-field electroretinograms (ERGs) recorded with skin electrodes before and after the vitrectomy.At present, there is no consensus on whether patients with bleb-related endophthalmitis should be treated with PPV or treated solely by intravitreal antibiotics. It was recently reported that vitrectomy using an irrigation solution containing 0.025% PI followed by postoperative antibiotics was effective and safe for the treatment of endogenous endophthalmitis and postoperative endophthalmitis. However, iodine is known to be retinotoxic depending on its concentration.Electroretinography is a useful method to evaluate the safety of medications because it represents the physiology of the entire retina. However, conventional recording procedures with contact lens electrodes cannot be used in eyes with bleb associated endophthalmitis. Therefore, we performed ERG using skin electrodes which were introduced relatively recently. As a result, electroretinographic response showed that retinal function was not altered after surgery in these two cases.Keywords: blebitis, electroretinography, bleb-related endophthalmitis, povidone iodine irrigation, vitrectomy

Yuki Komi,1 Takeshi Katsumoto,1 Yuji Yoshikawa,1 Masayuki Shibuya,1 Takuhei Shoji,1,2 Jun Makita,1 Kei Shinoda1 1Department of Ophthalmology, Saitama Medical University, Iruma, Saitama, Japan; 2Koedo Eye Institute, Kawagoe, Saitama, JapanCorrespondence: Kei Shinoda, Department of Ophthalmology, Saitama Medical University, 38 Morohongo, Moroyama, Saitama, 350-0495, Japan, Tel +81-4-9276-1250, Fax +81-4-9295-8002, Email shinok@saitama-med.ac.jpRationale: Development and spontaneous closure of a macular hole (MH) in a vitrectomized eye is relatively rare. We report our findings in a case in which vitrectomy was performed successfully to treat a vitreous hemorrhage (VH), but a MH developed eight months later. The MH spontaneously closed 2 weeks later, but then reopened. A second vitrectomy was performed with insertion of the internal limiting membrane flap into the MH which led to the successful closure of the MH. The purpose of this article is to present an explanation of how MH developed in this eye without vitreous traction.Patient: A 64-year-old woman visited an eye clinic with vision reduction in her right eye of 3 days duration. A VH was detected in the right eye and pars plana vitrectomy (PPV) was performed. A retinal tear was detected which was the origin of the VH. The vision was restored to a decimal visual acuity of 1.2. Eight months later, the patient noticed that her vision was distorted and was referred to our hospital.Diagnosis: Optical coherence tomographic (OCT) images showed a thin epiretinal membrane on the macula, cystoid changes in the macular area, and a full-thickness MH.Interventions: The MH closed spontaneously in two weeks, however a lamellar MH with an epiretinal proliferation (EP) developed 11 months later. Two months later, OCT showed cyst-like changes in the retina and a full-thickness MH. A second PPV was performed with the insertion of the ILM flap and EP into the MH to close the MH. Her visual acuity improved, and distorted vision was not present.Lessons: Clinicians should be aware that a MH can develop in a vitrectomized eye without vitreous traction but can close spontaneously. We conclude that careful follow-up examinations are necessary even in vitrectomized eyes.Plain Language Summary: We report our findings in a case in which a macular hole (MH) developed 8 months after vitrectomy and spontaneously closed but then reopened. Finally, the MH was closed after a second vitrectomy. Optical coherence tomographic images showed changes in the macular microstructure, eg, the presence of a thin epiretinal membrane on the retina, cystoid changes in the retina, and a full-thickness MH. We discuss the mechanism of MH development and surgical treatment.Keywords: epiretinal proliferation, full-thickness macular hole, lamellar macular hole, optical coherence tomography, spontaneous closure, vitrectomy

Wataru Inami, Masayuki Shibuya, Tomoyuki Kumagai, Jun Makita, Kei Shinoda Department of Ophthalmology, Saitama Medical University Faculty of Medicine, Saitama, JapanCorrespondence: Kei Shinoda, Department of Ophthalmology, Saitama Medical University Faculty of Medicine, Saitama, Japan, Tel +81-49-276-1250, Email shinodak@med.teikyo-u.ac.jpAbstract: Although intraocular lymphoma (IOL) mainly has have vitreous opacity and subretinal infiltration, its clinical symptoms are diverse. We report a case of IOL that mainly showed exudative retinal detachment in which analysis of IgH gene rearrangement (AIGHR) of the collected subretinal fluid sample was useful for diagnosis. A 77-year-old woman developed decreased left visual acuity for 1 month. She had been treated for dermatomyositis, diabetes mellitus, and right parotid tumor for 3 years. Visual acuity was 0.1 OD and counting fingers OS. Slit-lamp examination showed grade 4 (Emery-Little classification) nuclear cataract in both eyes and keratoprecipitates and tan vitreous opacity in the left eye. Fundoscopy details were unclear except for a vaguely observable optic nerve head due to yellow-brown vitreous opacity, which we judged as an old vitreous hemorrhage. Phacovitrectomy was performed and almost total retinal detachment was found, except for a part of the superior periphery. Since no retinal break was found and a wide range of thin membrane-like tissue was found on the surface of the retina, the surgeon suspected primary IOL and performed unplanned biopsy. The peripheral vitreous was collected as a sample, and then the subretinal fluid was collected through an intentional break to prevent mixing with other fluids. The subretinal strand was gently removed and collected. Cytology showed class III, the IL10/IL6 ratio was low, and AIGHR was positive. Postoperatively, fundus autofluorescence showed no abnormality, no leakage was observed on fluorescein and indocyanine green angiography, and the location of typical infiltration lesions under the retina was unclear. There were no positive findings on systemic examinations and a diagnosis of primary IOL was made. The main symptoms of this case were vitreous opacity and exudative retinal detachment, and AIGHR using subretinal fluid was useful for diagnosis.Keywords: primary intraocular lymphoma, exudative retinal detachment, IgH gene rearrangement, pars plana vitrectomy

Brown adipose tissue (BAT) acts in mammals as a natural defense system against hypothermia, and its activation to a state of increased energy expenditure is believed to protect against the development of obesity. Even though the existence of BAT in adult humans has been widely appreciated, its cellular origin and molecular identity remain elusive largely because of high cellular heterogeneity within various adipose tissue depots. To understand the nature of adult human brown adipocytes at single cell resolution, we isolated clonally derived adipocytes from stromal vascular fractions of adult human BAT from two individuals and globally analyzed their molecular signatures. We used RNA sequencing followed by unbiased genome-wide expression analyses and found that a population of uncoupling protein 1 (UCP1)-positive human adipocytes possessed molecular signatures resembling those of a recruitable form of thermogenic adipocytes (that is, beige adipocytes). In addition, we identified molecular markers that were highly enriched in UCP1-positive human adipocytes, a set that included potassium channel K3 (KCNK3) and mitochondrial tumor suppressor 1 (MTUS1). Further, we functionally characterized these two markers using a loss-of-function approach and found that KCNK3 and MTUS1 were required for beige adipocyte differentiation and thermogenic function. The results of this study present new opportunities for human BAT research, such as facilitating cell-based disease modeling and unbiased screens for thermogenic regulators.

Brown adipose tissue (BAT) dissipates chemical energy in the form of heat as a defence against hypothermia and obesity. Current evidence indicates that brown adipocytes arise from Myf5 + dermotomal precursors through the action of PR domain containing prot

Brown adipose tissue (BAT) dissipates chemical energy and generates heat to protect animals from cold and obesity. Rodents possess two types of UCP-1 positive brown adipocytes arising from distinct developmental lineages: "classical" brown adipocytes devel