Pregnancy and the eye. Changes in morphology of the cornea and the anterior chamber of the eye in pregnant woman.

OBJECTIVES: The main goal of the study was to determine whether uncomplicated pregnancy and natural labor exert influence on the cornea and the anterior chamber of the eye. MATERIAL AND METHODS: The study included 114 eyes of 57 women in age of 21-35 years old. Only patients in the physiological pregnancy and giving natural birth were recruited into study. Prospective observative examination was performed. Patients were diagnosed twice: in 36 HBD and 6 weeks after labor. Using the Scheimpflug camera (Pentacam system) the following parameters were assessed: central corneal thickness (CCT), keratometric parameters: flat (K1) and steep (K2), astigmatism value and axis, anterior chamber depth (ACD), anterior chamber volume (ACV) and anterior chamber angle (ACA). The statistical analysis was carried out in the StatSoft Statistica 13 program. RESULTS: CCT value is greater in the third trimester than in 6th week after the labour. ACD and ACA values are higher in 36 HBD than in the post-partum period but the difference is not statistically important (p > 0.05). K1, K2, cylindrical refraction error, axis of cylindrical refraction error do not change. CONCLUSIONS: Authors claim that it is the result from an increase in water retention in the corneal stroma as a response to hormonal changes. The plasticity of the anterior chamber seen before delivery can be a natural adaptive mechanism of the female body, which counteracts the excessive increase in intraocular pressure in the second stage of delivery.

Changes in the parameters of the anterior segment of the eye in pregnant women - literature review.

The physiology of pregnancy is a curious issue for specialists from different branches of medicine and science. In this systematic review, the attention was focused on changes in eyes during pregnancy and confinement. To summarise and systematize actual knowledge in eyes' changes during pregnancy, publications from years 2011-2017 were analysed. Stud-ies about parameters of corneal endothelial cells, corneal biomechanical parameters, keratometric variables, intraocular pressure and biometry of the anterior chamber were compared. The conducted studies demonstrated the unambiguous character of changes only in case of intraocular pressure, which decreased during the II and III trimesters of pregnancy. Inconsistent study methods and low number of examined patients did not enable to draw explicit conclusions in context of other parameters of the anterior segment of the eye in pregnant women. It is indicated to perform further studies on a representative and homogeneous group of female patients.

The etiology, diagnostics, and treatment of the spasm of the near reflex - a narrative review.

Physiological adaptation of the eye to the visual perception of near objects consists of the "near triad": convergence, accommodation, and pupil miosis. Normally, these tend to revert when one stops fixating on a near object. Spasm of the near reflex (SNR) is a pathological phenomenon, which manifests itself by the persistence of the above-mentioned adjustments, which prevents the eye from returning to its relaxed state. In this narrative review, we aim to summarize the etiology, diagnostics, treatment, and prevention of SNR. The literature review was performed by searching online databases. The clinical presentation of SNR is diverse; it presents as isolated accommodative spasm more frequently than impairment of all three components of the near triad. Patients usually present with fluctuations in visual acuity, blurred vision, diplopia, and asthenopia. The etiology is not fully understood. Potential causes include neuroanatomic, organic, and psychogenic disorders. The diagnosis is clinical, based on the constellation of symptoms and assessment of the near triad. The diagnostic golden standard is a cycloplegic examination of refraction, preferably using cyclopentolate hydrochloride (1%, 0.5%, or 0.1% solution). The first-line treatment requires the administration of a cycloplegic drug in combination with plus lenses, flipper lenses, optical fogging, or miotics. For secondary cases, causal treatment should be implemented. Prevention of SNR should be based on eliminating modifiable risk factors. We propose including screening for SNR symptoms in every ophthalmic examination, especially among patients with psychogenic or neural disorders, after brain trauma, or young adults spending much time in front of computer screens.

Visual Snow: A Review on Pathophysiology and Treatment.

OBJECTIVE: Visual snow (VS) is a rare clinical entity in neuro-ophthalmology. It is described as the presence of flickering dots affecting the whole visual field, often compared by patients to snow or pixelated television static. Importantly, it can be an alarming symptom for many patients, lowering their quality of life. Our purpose is to increase awareness of this disease, because many healthcare professionals have difficulty identifying symptoms as the nature of the condition is subjective. In this review, we aimed to describe the updates in the etiology and treatment of visual snow. We searched for articles in English, presenting original data and published after December 2019. Different studies show inconsistent data. Neuroimaging studies found, among other things, hypermetabolism of the lingual gyrus, increased gray matter in different brain areas, and altered connectivity in visual pathways. However, these findings were not present in all patients. According to the literature, among the most effective drugs is lamotrigine. Unfortunately, it also carries a risk of worsening the symptoms. It is crucial to remember that VS can be worsened or induced by alcohol, recreational drugs, and certain medication. In terms of treatment, nonpharmacological approaches such as color filters and repetitive Transcranial Magnetic Stimulation were also used. INTERPRETATION: Further studies are needed to understand the nature of VS fully. Even though the pathophysiology and effective treatment of the condition remains unknown, expanding the knowledge about visual snow can impact the comfort of patients.

Diagnostic and prognostic values of conjunctival and oral biopsies analyzed by direct immunofluorescence in patients with mucous membrane pemphigoid.

Introduction: Mucous membrane pemphigoid (MMP) is diagnosed on the basis of a characteristic clinical picture (a predilection for mucosal involvement and scarring in the affected tissues) and a positive direct immunofluorescence (DIF) result. Methods: In this study, we compare the diagnostic and prognostic values of conjunctival and oral biopsies analyzed by DIF in patients with MMP. Sixteen patients with MMP and mucosal involvement as a predominant symptom were classified into three groups based on the clinical picture. Oral and conjunctival DIF were performed on all patients. Results: Our study showed that patients with simultaneous oral and conjunctival involvement had a positive oral DIF in 83% and a positive ocular DIF in 100% of the examined cases, respectively. Patients with isolated ocular MMP had a positive oral DIF in 50% and a positive ocular DIF in 66% of the examined cases, respectively. Patients with only oral involvement with MMP had a positive oral DIF in 100% and a positive ocular DIF in 50% of the examined cases, respectively. Discussion: Oral biopsy should be performed first and is usually sufficient for the diagnosis, even in patients with exclusively ocular MMP, whereas in patients without clinical ocular involvement, ocular DIF is positive in half of the cases and may be a predictive factor for ocular lesions in the future.

[IThe use of Pentacam for keratoconus diagnosis and progress evaluation]. / Zastosowanie aparatu Pentacam w diagnostyce i ocenie progresji stozka rogówki.

The authors present possibilities of Pentacam examination for keratoconus diagnosis and progress evalutaion. They describe meaning of data comming from Pentacam 3D model measurements; indexes for corneal surface disturbances, analysis of anterior and posterior corneal surface, sense of connection data from keratometric and pachymetric measurements for keratoconus detection.

Post-mortem Iris Decomposition and its Dynamics in Morgue Conditions.

With increasing interest in employing iris biometrics as a forensic tool for identification by investigation authorities, there is a need for a thorough examination and understanding of postmortem decomposition processes that take place within the human eyeball, especially the iris. This can prove useful for fast and accurate matching of antemortem with postmortem data acquired at crime scenes or mass casualties, as well as for ensuring correct dispatching of bodies from the incident scene to a mortuary or funeral homes. Following these needs of forensic community, this paper offers an analysis of the coarse effects of eyeball decay done from a perspective of automatic iris recognition. We analyze postmortem iris images acquired for a subject with a very long postmortem observation time horizon (34 days), in both visible light and near-infrared light (860 nm), as the latter wavelength is used in commercial iris recognition systems. Conclusions and suggestions are provided that may aid forensic examiners in successfully utilizing iris patterns in postmortem identification of deceased subjects. Initial guidelines regarding the imaging process, types of illumination, and resolution are also given, together with expectations with respect to the iris features decomposition rates. Visible iris features possible for human, expert-based matching persists even up to 407 h postmortem, and near-infrared illumination is suggested for better mitigation of corneal opacity while imaging cadaver eyes (Post-mortem iris decomposition and its dynamics in morgue conditions. ArXiv pre-print, 2019).

Does pregnancy influence eye parameters? Assessment of choroidal thickness using EDI-OCT before and after labour depending on the way of delivery method.

OBJECTIVES: The aim of this study is to assess the choroidal thickness (CT) with use of EDI-OCT in patients before and after delivery depending on the mode of delivery. MATERIAL AND METHODS: The study involved 146 eyes of 73 patients aged 20-34 years, after natural labour (66 eyes) and C-section (80 eyes). Main inclusion criteria: Informed consent to participate in the study, age 18-35 years, single pregnancy, spherical refraction error -4.00 to +4.00 D, no eye pathologies, no surgery and ophthalmic procedures-including refractive surgery, childbirth after 36 weeks of pregnancy, BCVA = 1.0. Patients were examined twice: in 36 WG and on 6th week after the birth. All examinations were carried out between 8:00 am and 10:00 am in order to avoid daily cycle fluctuations. CT measurements were made manually by two independent researchers at: subfoveal and 500 µm, 1000 µm, 1500 µm, 3000 µm temporally and nasally. The student's t-test was made. RESULTS: In C-section group CT differences before and after delivery were statistically significant in 7/9 of the analysed areas. Mean subfoveal choroidal thickness was 370.86 µm vs 388.71 µm in 36 WG and in 6th week postpartum respectively (p = 0.0003). In women after natural labour, differences were statistically significant in 3/9 of the analysed areas. Mean subfoveal choroidal thickness was 303.27 µm vs 308,34 µm in 36 WG and in 6th week postpartum respectively (p = 0.4800). CONCLUSIONS: The thickness of the choroid was lower in women in 36 WG in comparison to 6th week after birth. Changes in the thickness of the choroid are particularly noticeable in women after caesarean section.

[Louis Braille (1809-1852)--inventor of raised dots system]. / Louis Braille (1809-1852)--twórca pisma dla niewidomych.

Louis Braille was born on January 4th 1809 in Coupvray, France. An injury to his eye at the age of three, resulted in total loss of vision. In 1819 he entered the Institute for Blind Youth in Paris. There he would live, study, and later teach. When he was fifteen, he developed system of reading and writing by means of raised dots, which is known today as Braille. The basis of the Braille system is known as a Braille cell. The cell is comprised of six dots numbered in a specific order. Each dot or combination of dots represents a letter of the alphabet. This Braille system has established itself internationally and formed the basic Braille for all languages.

[Pentacam--the new way for anterior eye segment imaging and mapping]. / Pentacam--nowe mozliwosci obrazowania przedniego odcinka galki ocznej.

Accurate preoperative measurements are required for refractive and cataract surgery. Pentacam is a new imaging system for anterior eye segment study. The authors present technique and the range of measurements; topography of both anterior and posterior corneal surface from limbus to limbus, densitometry, anterior chamber angle, volume and depth, lens densitometry and 3D-virtual model of the anterior eye segment are taken. All those structures are shown thanks to rotating Scheimpflug camera, which generates three-dimension images. Any eye movements are detected by a second camera and corrected for, in the process. All results are written down on PC and are available for the prospective studies.

[The visual acuity impairment as the only sign of cerebral aneurysms--case report]. / Obnizenie ostrosci wzroku jako jedyny objaw tetniaków tetnic mózgowych--opis przypadku.

Cerebral aneurysms are the most common reason of subarachnoid haemorrhage at the age of 50-60. Though the results of such haemorrhage are severe (high morbidity and mortality), it is quite often, the first noticeable sign of the problem. Previous symptoms i. e. headache, ophthalmic disturbances, temporary neurological symptoms are often passed over. The authors present the case of a young woman with cerebral aneurysms, in which the visual acuity impairment was the only symptom of the disease.