Crystalline Lens Research Articles

Patterns of Crystallin Gene Expression in Differentiation State Specific Regions of the Embryonic Chicken Lens.

PurposeTransition from lens epithelial cells to lens fiber cell is accompanied by numerous changes in gene expression critical for lens transparency. We identify expression patterns of highly prevalent genes including ubiquitous and enzyme crystallins in the embryonic day 13 chicken lens.MethodsEmbryonic day 13 chicken lenses were dissected into central epithelial cell (EC), equatorial epithelial cell (EQ), cortical fiber cell (FP), and nuclear fiber cell (FC) compartments. Total RNA was prepared, subjected to high-throughput unidirectional mRNA sequencing, analyzed, mapped to the chicken genome, and functionally grouped.ResultsA total of 77,097 gene-specific transcripts covering 17,450 genes were expressed, of which 10,345 differed between two or more lens subregions. Ubiquitous crystallin gene expression increased from EC to EQ and was similar in FP and FC. Highly expressed crystallin genes fell into three coordinately expressed groups with R2 ≥ 0.93: CRYAA, CRYBB2, CRYAB, and CRYBA2; CRYBB1, CRYBA4, CRYGN, ASL1, and ASL; and CRYBB3 and CRYBA1. The highly expressed transcription factors YBX1, YBX3, PNRC1, and BASP1 were coordinately expressed with the second group of crystallins (r2 > 0.88).ConclusionsAlthough it is well known that lens crystallin gene expression changes during the epithelial to fiber cell transition, these data identify for the first time three distinct patterns of expression for specific subsets of crystallin genes, each highly correlated with expression of specific transcription factors. The results provide a quantitative basis for designing functional experiments pinpointing the mechanisms governing the landscape of crystallin expression during fiber cell differentiation to attain lens transparency.

Association of alkaptonuria and low dose nitisinone therapy with cataract formation in a large cohort of patients.

Homogentisic acid (HGA) lowering, disease modifying off‐label nitisinone therapy has been used in the United Kingdom National Alkaptonuria Centre (NAC) since 2012. This study evaluated the serendipitous observation of cataract in a large cohort of patients with the very rare disease alkaptonuria (AKU), over a 5‐year period. Patients with AKU who attended the NAC since 2012. Standard physical examination and ocular assessment, including photographs of the crystalline lens were taken before commencement of nitisinone 2 mg daily and annually over 5 years. Photographs were randomised and graded by two independent observers using the WHO cataract classification. AKU patients who did not receive nitisinone were included as a control group. HGA was measured on acidified 24 h urine (u‐HGA24) and HGA and tyrosine in fasting acidified serum samples (sHGA, sTYR) at each visit. Patients without suitable lens images were excluded. Cataract (mean grade 1) was noted at baseline in 47 out of 62 (76%) with a mean (SD) age of 44 (14) years. In nitisinone‐treated patients, there were significant increases in the mean grade of nuclear (0.18, p < 0.01) and cortical (0.38, p < 0.01) lens opacities over the mean duration of 4.93 years of the study. Worsening of the nuclear cataract and cortical lens opacities by at least 1 grade was noted in 14 out of 46 (30%) and 11 out of 46 (24%) patients, respectively. There is an increased prevalence and progression of cataract in AKU and a possible association of nitisinone with cataract progression.

The Effect of Cataract on Color Vision Measurement with the Low-Vision Cambridge Colour Test: Providing an Adjustment Factor for Clinical Trials.

PurposeTo quantify the effect of cataract on color vision as measured by the low-vision Cambridge Colour Test (lvCCT; Cambridge Research Systems) and to understand whether different types and severities of cataract have different effects on color vision.DesignCohort study.ParticipantsPatients aged 18 to 95 undergoing routine cataract surgery at the Oxford Eye Hospital.MethodsThe lvCCT was performed to measure color sensitivity in both eyes both before and after surgery. The crystalline lens was examined and graded according to the Lens Opacities Classification System III to determine the type and severity of cataract. Measures of repeatability were performed for the data to explore test–retest bias using Bland–Altman analysis. The Wilcoxon signed-rank test was performed to assess the effect of cataract on color vision by comparing control and surgical test measurements. Three multiple linear regressions were performed to relate cataract grading or severity to color vision measurements.Main Outcome MeasuresColor discrimination along each of the protan, deutan, and tritan confusion lines.ResultsThe Wilcoxon signed-rank test showed a statistically significant difference in both the protan (P = 0.024) and tritan (P = 0.020) axes on comparison of control and surgical test measurements. As severity of cataract increased, color vision sensitivity was affected more greatly, and nuclear sclerotic cataract showed the most profound effect on color vision sensitivity in the lvCCT; however, the linear regression models showed that these observations did not reach statistical significance.ConclusionsCataract surgery has a statistically significant effect on color vision in both the protan and tritan axes. The effects of specific subtypes of cataract and different severities could not be elucidated because of the high prevalence of patients with mixed cataract. The lvCCT color sensitivity measurements are used regularly as outcome measures in clinical gene therapy trials involving vitreoretinal surgery, and vitrectomy accelerates cataract formation. Therefore, it is important to quantify the effect of cataract on color vision measurements so that it may be taken into account when used as an outcome measure in clinical trials. We were unable to derive a precise correction factor for cataract on color vision measurements.

Intraocular Temperature Distribution in Eyes Undergoing Different Types of Surgical Procedures during Vitreous Surgery.

Vitreous temperature has been reported to vary during intraocular surgery. We measured the temperature at three intraocular sites, just posterior to the crystalline lens (BL), mid-vitreous (MV), and just anterior to the optic disc (OD), and investigated temperature changes before and after different types of surgical procedures in 78 eyes. The mean temperature at the beginning was 30.1 ± 1.70 °C in the anterior chamber, 32.4 ± 1.41 °C at the BL, 33.8 ± 0.95 °C at the MV, and 34.7 ± 0.95 °C at the OD. It was lowest at the BL, and highest at the OD. The mean temperature after cataract surgery was slightly lower especially at an anterior location. Thus, the temperature gradient became slightly flatter. The mean temperature after core vitrectomy was even lower at all sites and a gradient of the temperature was not present. The mean temperature after membrane peeling was significantly higher than that after core vitrectomy, and there was no gradient. The mean temperature after fluid/air exchange was lower at the BL and higher at the MV and at the OD. Thus, a gradient of higher temperatures at the OD appeared. The intraocular temperature distribution is different depending on the surgical procedure which can then change the temperature gradient. The temperature changes at the different intraocular sites and the gradients should be further investigated because they may affect the physiology of the retina and the recovery process.

Angle closure secondary to lens remnants in a patient with presumed aphakia: case report

BackgroundEyes with a short axial length or anterior chamber depth often develop narrowed anterior chamber angles in association with an enlarging crystalline lens. We report a case of a patient who presented in angle closure, with a distant history of prior intervention for congenital cataracts and was presumed to be aphakic.Case presentationA 78-year-old male presented with acute onset unilateral eye pain and blurred vision. He was found to have increased intraocular pressure, anteriorly bowed iris, and angle closure. Despite prior documentation of aphakia after treatment for congenital cataracts, detailed workup revealed residual crystalline lens material pushing the peripheral iris anteriorly. Further history confirmed that the patient underwent a procedure in the 1940’s to remove lens material centrally but was not truly aphakic. The patient was treated with anterior chamber paracentesis and intraocular pressure lowering drops. His intraocular pressure remains controlled with medical therapy alone.ConclusionsPatients that appear to be aphakic centrally may still present with angle closure secondary to residual peripheral lens material. This case highlights the importance of keeping this etiology on the differential in a patient with presumed aphakia.

Erratum in: Age-Dependence of the Peripheral Defocus of the Isolated Human Crystalline Lens.

Erratum in: Age-Dependence of the Peripheral Defocus of the Isolated Human Crystalline Lens.

Feasibility of cavitation nucleation in the crystalline lens

Presbyopia is the age-related stiffening of the crystalline lens, reducing near vision. We propose ultrasonic cavitation to interact with the lens structure and restore its flexibility. Here, we present early results on the feasibility of the technique. First, the cavitation threshold was determined: the focus of a 4-elements transducer was placed in the lens nucleus in a porcine eye, and signals emitted in the focal area were acquired using an imaging array and reconstructed using frequency-domain passive cavitation imaging (PCI) with Richardson-Lucy deconvolution. Inharmonic emissions inside the lens were calculated, and we evidenced two distinct populations: low and high amount of signal inside the lens, when cavitation was absent or present, respectively. Peak negative pressure of 23 MPa for 20 μs pulses at 1.1 MHz provided a clear chance of nucleating cavitation with our system. Exposures were performed after 10 s of cavitation using a PRF of 250 Hz. Cavitation clouds were clearly visible in B-mode images for both 6-months old and 3-years old porcine eyes. The absence of cataract was confirmed on transparency images, and histology revealed no damages to the lens structure. These preliminary results are encouraging towards the application of cavitation in the crystalline lens.

Ameliorative effect of pioglitazone on glucose induced glycation of α-crystallin: Management of complications associated with diabetic retinopathy

The glycation and aggregation of lens proteins significantly contribute to the onset of diabetic cataracts as well as the retinopathy. The glycation exerts numerous alterations in the tertiary structural of proteins. Moreover, the covalent crosslinking of lens crystallins also contribute to the cataract formation. In this article, the effect of pioglitazone on glucose induced glycation and aggregation α-crystallin was examined. A remarkable inhibition of early glycation products (~80%) and advanced glycation products (~75%) was recorded by the treatment of pioglitazone. There was >75% recovery in biochemical marker (carbonyl content). The presence of 150 μM of pioglitazone reduced the free lysine modifications to 35%. Treatment of pioglitazone also protected the secondary structural alterations induced by glycation and inhibited the formation of protein aggregates. The interaction studies showed that pioglitazone interacted with α-crystallin via moderate binding affinity. The interaction between pioglitazone interacted and α-crystallin was energetically and entropically favourable. The complex of pioglitazone with studied protein stable in which RMSF, Rg, SASA, RMSD, and the secondary structural components was not affected. The findings show antiglycation activity of pioglitazone along with its mechanism of action highlighting the ability of drug to be possibly developed novel as glycation inhibitor.

Etiology of white pupillary reflex in pediatric age group.

Background: Leukocoria means white pupil. Normal pupil appears black in children and adults. The typical red reflex is due to retro-illumination of choroidal vessels reflected via the retina, vitreous humor, crystalline lens, aqueous humor, pupil, and cornea. If there is interference in these structures, it would result in a changed red reflex, or leukocoria. Immediate family members are highly likely to detect the first indicator and the pediatrician or general ophthalmologist is usually the first to be visited.The aim of the study was to find out the prevalence of common causes of white pupillary reflex in children, to undertake early diagnosis and treatment, and to reduce morbidity and death. This study aimed to see how common it is for children to have a white pupillary reflex when they visit a pediatric ophthalmologist.Objective: Determine the incidence of conditions that cause a white pupillary reflex in children who visited Hayatabad Medical Complex Hospital in Peshawar.Materials and methods: This study was carried out in the Ophthalmology unit of HMC Hospital Peshawar, from January 2021 to December 2021. 168 patients were enrolled in the study. We included all patients of up to 10 years and both genders with the above findings. Workup for leukocoria was done to find the exact cause that included fundoscopy, B-Scan, MRI, and CT scans. Examination under anesthesia (EUA) was carried out for uncooperative children for detailed fundus examination. Patient data was recorded and a proforma was made to collect all the necessary information. Family history was taken in detail during this study.Results: The most common cause of aberrant pupillary reflex in children aged 1 to 10 years was cataract, 79.76 percent of patients having it. Retinoblastoma (12.5%), Coats disease (3.5%), retinal detachment (2.9%) and persistent hyperplastic vitreous (PHPV) (1.1%) were other notable causes found.Conclusion: Leukocoria is a critical clinical finding, and if parents or primary care physicians notice it, the patient requires a complete follow-up examination by a pediatric ophthalmologist to determine the etiology.

Measurement of Longitudinal Chromatic Aberration in the Last Crystalline Lens Surface Using Hartmann Test and Purkinje Images.

Research has shown that longitudinal chromatic aberration (LCA) of the human eye is generated across all of the eye’s optical surfaces. However, it may not be necessary to measure the LCA from the first surface of the cornea to the retina, as it is known that most of the changes that can modify the path of light occur from the first surface of the cornea to the last surface of the crystalline lens. This investigation presents the study of an objective technique that allows the measurement of longitudinal chromatic aberration (LCA) on the last crystalline lens surface by developing a pulse width wavefront system using a Hartmann test, Purkinje image, and Zernike polynomial. A blue pulse (440–480 nm) and a red pulse (580–640 nm) were used to generate a pattern of spots in the human eye. This pattern generated on the posterior surface of the crystalline lens of the human eye allows the reconstruction of the wavefront via a modal method with Zernike polynomials. Once the wavefront is reconstructed, Zernike coefficients can be used to quantify the LCA. The methodology and objective measurements of the magnitude of the longitudinal chromatic aberration of five test subjects are explained in this article.

Total Retinal Detachment Following Traditional Couching

A 65-year-old patient with no notable history, from low socioeconomic status, presented to the ophthalmology clinic for visual impairment of the left eye three months after a traditional couching. Visual acuity was limited to light perception. Slit-lamp examination showed cells and flare in the anterior segment and the vitreous. Fundus examination showed a complete retinal detachment including the fovea with proliferative vitreoretinopathy stage B and two large peripheric retinal tears inferiorly contiguous to the crystalline lens. Surgical treatment was based on pars plana vitrectomy with phacofragmentation of the crystalline lens, pneumatic retinopexy and endophotocoagulation of the retinal tears. Clinical evolution was marked by the improvement of the visual acuity to 20/200 two months after surgery.

Experiences of Treatment With Contact Lenses in Aphakic Children With Unilateral Congenital Cataract: A Retrospective Study.

Congenital cataract is a condition compromising the eye's crystalline lens in infants and is usually diagnosed at birth. It can lead to irreversible vision loss if not promptly detected and treated, especially in unilateral cases. Nowadays, children with congenital cataracts can undergo surgical removal of their opacified crystalline lenses, and visual rehabilitation is mandatory to prevent deep amblyopia. Contact lenses, predominantly of rigid gas-permeable (GP) type, are gaining more popularity for this matter. In this retrospective cohort study, unilateral aphakic children younger than 6 years referred to the Contact Lens Clinic at Farabi Eye Hospital from November 2011 to September 2019 were included. Seventy-six unilateral aphakic children with congenital cataracts (57.9% boys and 42.1% girls) rehabilitated with GP were studied. The mean age of diagnosis and referral to the contact lens clinic were 20.0±19.8 and 32.0±24.4 weeks, respectively, while the mean follow-up time was 12.44±26.28 months. The mean visual acuity for children capable of cooperating at the last follow-up was 0.98±0.62 log MAR. Among the participants, eight children (9.7%) were diagnosed as glaucoma suspects. The mean initial base curve and power of GP lenses were 7.86±0.39 mm and 23.29±5.52 diopters, respectively. Only 21 parents (27.6%) reported nonadherence to the scheduled part-time patch program. The results of this study showed GP-based optical treatment after early diagnosis, surgical removal of congenital cataracts, and a long-term close follow-up to be well tolerated by children and their parents, with acceptable parents' compliance and can thus be introduced as a safe and effective method to achieve desirable visual outcomes.

Intraocular scatter compensation with spatial light amplitude modulation for improved vision in simulated cataractous eyes.

Cataract is one of the common causes of visual impairment due to opacification of the crystalline lens. Increased intraocular scattering affects the vision of cataract patients by reducing the quality of the retinal image. In this study, an amplitude modulation-based scatter compensation (AM-SC) method is developed to minimize the impact of straylight on the retinal image. The performance of the AM-SC method was quantified by numerical simulations of point spread function and retinal images in the presence of different amounts of straylight. The approach was also experimentally realized in a single-pass system with a digital micro-mirror device used as a spatial amplitude modulator. We showed that the AM-SC method allows to enhance contrast sensitivity in the human eyes in vivo with induced scattering.

Axial Elongation During Short-Term Accommodation in Myopic and Nonmyopic Children.

PurposeAxial length increases during accommodation in adults and children; however, refractive error group differences are conflicting and have not been explored in pediatric populations. This study aimed to evaluate differences in accommodation-induced axial elongation between myopic and nonmyopic children.MethodsA range of ocular biometric measurements were captured during brief accommodation tasks (0, 3, 6, and 9 D) using a Badal optometer mounted to a noncontact optical biometer (Zeiss IOLMaster 700). Reliable measurements were captured for 15 myopic and 15 age- and sex-matched nonmyopic children. The average central corneal thickness (CCT), anterior chamber depth (ACD), crystalline lens thickness (LT), anterior segment length (ASL), vitreous chamber depth (VCD), and axial length (AL) were determined for each accommodation stimulus. Raw measurements of AL and VCD were corrected for the estimated error associated with LT increases during accommodation.ResultsAll biometric parameters, except CCT, changed significantly during accommodation (all P < 0.001). Myopic children exhibited significantly greater accommodation-induced axial elongation than nonmyopic children (P = 0.002) at the 3, 6, and 9 D accommodation stimuli, with a mean difference of 7, 10, and 16 µm, respectively (all pairwise comparisons, P ≤ 0.03). The changes in all other biometric parameters were not different between the refractive error groups (P ≥ 0.23).ConclusionsAccommodation-induced axial elongation was greater in myopic than nonmyopic children. This finding could support a potential mechanism linking near work, axial elongation, and myopia development in children or may reflect greater susceptibility to accommodation-induced axial elongation in children with established myopia.

Changes in DNA methylation hallmark alterations in chromatin accessibility and gene expression for eye lens differentiation

BackgroundMethylation at cytosines (mCG) is a well-known regulator of gene expression, but its requirements for cellular differentiation have yet to be fully elucidated. A well-studied cellular differentiation model system is the eye lens, consisting of a single anterior layer of epithelial cells that migrate laterally and differentiate into a core of fiber cells. Here, we explore the genome-wide relationships between mCG methylation, chromatin accessibility and gene expression during differentiation of eye lens epithelial cells into fiber cells.ResultsWhole genome bisulfite sequencing identified 7621 genomic loci exhibiting significant differences in mCG levels between lens epithelial and fiber cells. Changes in mCG levels were inversely correlated with the differentiation state-specific expression of 1285 genes preferentially expressed in either lens fiber or lens epithelial cells (Pearson correlation r = − 0.37, p < 1 × 10–42). mCG levels were inversely correlated with chromatin accessibility determined by assay for transposase-accessible sequencing (ATAC-seq) (Pearson correlation r = − 0.86, p < 1 × 10–300). Many of the genes exhibiting altered regions of DNA methylation, chromatin accessibility and gene expression levels in fiber cells relative to epithelial cells are associated with lens fiber cell structure, homeostasis and transparency. These include lens crystallins (CRYBA4, CRYBB1, CRYGN, CRYBB2), lens beaded filament proteins (BFSP1, BFSP2), transcription factors (HSF4, SOX2, HIF1A), and Notch signaling pathway members (NOTCH1, NOTCH2, HEY1, HES5). Analysis of regions exhibiting cell-type specific alterations in DNA methylation revealed an overrepresentation of consensus sequences of multiple transcription factors known to play key roles in lens cell differentiation including HIF1A, SOX2, and the MAF family of transcription factors.ConclusionsCollectively, these results link DNA methylation with control of chromatin accessibility and gene expression changes required for eye lens differentiation. The results also point to a role for DNA methylation in the regulation of transcription factors previously identified to be important for lens cell differentiation.

Subluxation of the Crystalline Lens in Marfan Syndrome

A 17-year-old patient with Marfan syndrome consulted in the emergency department for sudden onset of bilateral ocular pain, with no history of previous trauma, associated with severe headaches and vomiting [1]. His uncorrected visual acuity was reduced to “counting fingers” in the right eye, slit Lampe examination of the same eye showed major anterior dislocation (Figure 1) of a clear crystalline lens, with visible stretched zonules seen temporally.

Force of lifelong crystalline lens growth: chronic traumatic mechanical insult to the choroid.

To calculate the forces applied to the uvea and retina as a result of lifelong crystalline lens growth. Retrospective study. MRI Research, Inc., Middleburg Heights, Ohio; Institute of Ophthalmology and Visual Science UMDNJ-New Jersey Medical School, Newark, New Jersey; USC Psychology University of Southern California, Los Angeles. Magnetic resonance images were acquired from 15 phakic/pseudophakic eye pairs in patients with cataract (ages 46 to 83 years). Choroidal lengths were measured. The forces required to produce differences between phakic/pseudophakic choroidal lengths were calculated. The length of the choroid is greater in the phakic eye compared with the corresponding pseudophakic eye (n = 15), and this difference increases with age (P = .00006; power = 0.99). The corresponding choroidal strain also increases with age (P = .00003, power = 0.99) as do the forces required to produce such a change in choroidal length (P = .000008, power = 0.99). The authors theorize that lifelong crystalline lens growth applies a chronic, traumatic, mechanical insult to the uvea and retina. This previously unknown, ever-increasing, force appears to stretch the choroidal tissue and may be an intraocular pressure-independent modifiable risk factor for retinal disease. Implications exist for understanding the pathophysiology of retinal diseases in the aging eye that are often comorbid with cataracts, for example, glaucoma, macular degeneration, and diabetic retinopathy.

The Blue Light Hazard Versus Blue Light Hype

The blue light hazard is the experimental finding that blue light is highly toxic to the retina (photic retinopathy), in brief abnormally intense exposures, including sungazing or vitreoretinal endoillumination. This term has been misused commercially to suggest, falsely, that ambient environmental light exposure causes phototoxicity to the retina, leading to age-related macular degeneration (AMD). We analyze clinical, epidemiologic, and biophysical data regarding blue-filtering optical chromophores. Perspective. Analysis and integration of data regarding the blue light hazard and blue-blocking filters in ophthalmology and related disciplines. Large epidemiologic studies show that blue-blocking intraocular lenses (IOLs) do not decrease AMD risk or progression. Blue-filtering lenses cannot reduce disability glare because image and glare illumination are decreased in the same proportion. Blue light essential for optimal rod and retinal ganglion photoreception is decreased by progressive age-related crystalline lens yellowing, pupillary miosis, and rod and retinal ganglion photoreceptor degeneration. Healthful daily environmental blue light exposure decreases in older adults, especially women. Blue light is important in dim environments where inadequate illumination increases risk of falls and associated morbidities. The blue light hazard is misused as a marketing stratagem to alarm people into using spectacles and IOLs that restrict blue light. Blue light loss is permanent for pseudophakes with blue-blocking IOLs. Blue light hazard misrepresentation flourishes despite absence of proof that environmental light exposure or cataract surgery causes AMD or that IOL chromophores provide clinical protection. Blue-filtering chromophores suppress blue light critical for good mental and physical health and for optimal scotopic and mesopic vision.

Profil Pasien Katarak di Poliklinik Mata RS PKU Muhammadiyah Rogojampi

Cataracts are the world’s second leading cause of blindness, trailing only uncorrected refractive errors. Based on the 2014-2016 RAAB survey, the blindness prevalence in 15 Indonesian provinces ranged from 1.4% in West Sumatra and 4.4% in East Java. A cataract is a clouding of the intraocular crystalline lens, in which this cloudiness can lead to a decreased vision function, and even it may trigger the emergence of blindness. The blindness caused by cataracts is preventable. This research aims to identify and collect data on the frequency of cataract patient profiles at the Eye Polyclinic of PKU Muhammadiyah Rogojampi Hospital in 2021. The research method utilized in this study was a retrospective descriptive study by applying a cross-sectional approach. The research data were attained from the secondary data, particularly in medical record examinations at PKU Muhammadiyah Rogojampi Hospital. This study was conducted from June to October 2021. The population of this research consisted of all cataract patients at PKU Muhammadiyah Rogojampi Hospital, in which the sample comprised 41 respondents. The data analysis using univariate analysis was denoted in the frequency distribution table. The results demonstrated that out of 41 respondents, 19 patients (46%) were about 60-69 years old, 26 patients (63%) were males, and 12 patients (29%) worked as farmers.

Development of the Radiation Protective Curtain for the Dose Reduction of Caregivers during Computed Tomography Examinations

During computed tomography (CT) examinations, it may be necessary to assist the patient to maintain an appropriate body position. However, there is little protective equipment available for caregivers who approach the gantry. This study aimed to evaluate the effectiveness of novel radiation protective curtains in reducing radiation exposure to caregivers while assisting patients, especially during CT examinations of the head. The absorbed dose in air around the gantry during CT examinations of the head was measured using glass dosimeters. The measurement points from the center of the gantry were 40 to 120 cm in the front, 0 to 100 cm for each side in the right and left, and 60 to 180 cm from the floor. Measurements were performed at each 20-cm interval, and all points were accumulated 10 times. The absorbed dose in air in a CT room was compared with and without the protective curtains. Next, we assumed the height of the caregiver to be 170 cm, and measured the points for the crystalline lens, chest, and abdomen. Also, using the protective glasses and the protective apron, we measured the absorbed dose in air for the caregivers behind the protective curtains. The absorbed exposure dose in air toward the crystalline lenses, chest, and abdomen was reduced more than 90% by using the protective curtains and more than 95% by using the protective apron and protective glasses in addition to them. This study showed the usefulness of protective curtains in reducing the absorbed exposure dose in air to caregivers.