Imaging of congenital toxoplasmosis macular scars with optical coherence tomography

Posterior Segment Optical Coherence Tomography in Uncooperative Paediatric Patients Using Exo-Illumination and Microscope-Integrated Optical Coherence Tomography

BACKGROUND AND OBJECTIVE

To describe a non-invasive technique for the acquisition of retinal optical coherence tomography (OCT) scans in paediatric patients undergoing examination under general anaesthesia (EUA) using microscope-integrated OCT (MIOCT).

STUDY DESIGN

Prospective observational study Methods and Material: The study included 10 paediatric patients undergoing EUA for posterior segment pathology. These patients underwent OCT using MIOCT. No sclerotomy was made during imaging. The fundus was externally illuminated with a 25 gauge endoilluminator probe placed at the limbus and directed towards the posterior pole to aid in image acquisition by MIOCT (exo-illumination). Imaging for all patients was done by two trained vitreoretinal surgeons independently. Acquisition time was recorded for each surgeon. Interobserver variability in acquisition time and image quality was assessed to estimate the reliability of the novel imaging technique.

RESULTS

In nine cases (90%), MIOCT successfully imaged the posterior segment pathology while in one case (10%) of X-linked retinoschisis, it failed to detect an inner retinal break located anteriorly at the equator. The mean acquisition time for surgeons one and two was 211.75 ± 26.00 and 212.58 ± 23.47 seconds, respectively. There was no significant difference in total image acquisition time between the two surgeons (P = 1.0) and the findings of both surgeons were comparable for structural morphology. 4x4 mm-sized scans provided the best delineation in macular pathology, while a 16x16 mm scan size was best suited for localising the area of interest and post-equatorial pathology.

CONCLUSION

Using this technique acquisition of posterior segment OCT scans can be achieved non-invasively, using exo-illumination and MIOCT in paediatric patients undergoing EUA.

Foveal reorganization after treatment of acute foveal toxoplasmic retinochoroiditis

Purpose

To report a patient with impaired vision due to foveal involvement of toxoplasmic retinochoroiditis, who was successfully treated with intravitreal clindamycin and dexamethasone and oral therapy with azithromycin, trimethoprim-sulfamethoxazole, and prednisolone and led to successful visual and anatomic recovery.

Case presentation

A 32-year-old man presented with three-day history of gradually decreasing visual acuity, redness, pain and photophobia of the right eye. Anterior chamber cellular reaction, vitritis and a white retinochoroiditis patch with adjacent retinal vasculitis in the fovea was suggestive of the toxoplasmic retinochoroiditis. He was treated with intravitreal clindamycin and dexamethasone injection followed by six-week regimen of azithromycin, trimethoprim-sulfamethoxazole, and prednisolone. In serial optical coherence tomography imaging, retinitis patch changed to cavitary foveal destruction. Fovea reorganized gradually, and visual acuity concurrently improved from counting finger 3 m to 20/25.

Conclusion

In foveal toxoplasmic retinochoroiditis lesions, timely treatment is associated with retinal reorganization and visual improvement.

Optical Coherence Tomographic Finding in a Case of Congenital Macular Coloboma at King Abdulaziz University Hospital, Jeddah

Macular coloboma is a rare eye condition that affects around 0.5-0.7/10,000 of live births. Macular coloboma appears as a well-demarcated atrophic lesions that could affect one eye or both eyes on fundus examination. This is a case of a 33-year-old male patient who presented to the outpatient clinic with a history of poor vision in the left eye since childhood. He had a history of strabismus surgery for sensory exotropia (XT) in the left eye. Anterior segment examination of both eyes was normal while the fundus examination of both eyes revealed bilateral chorioretinal lesions in the macula which was larger in the left eye (OS) than the right eye (OD), representing bilateral chorioretinal coloboma. Congenital coloboma is a rare eye condition that leads to non-progressive decrease in visual acuity. Optical coherence tomography (OCT) is the modality of choice in diagnosing and describing macular coloboma.

Ocular coloboma-a comprehensive review for the clinician

Typical ocular coloboma is caused by defective closure of the embryonal fissure. The occurrence of coloboma can be sporadic, hereditary (known or unknown gene defects) or associated with chromosomal abnormalities. Ocular colobomata are more often associated with systemic abnormalities when caused by chromosomal abnormalities. The ocular manifestations vary widely. At one extreme, the eye is hardly recognisable and non-functional—having been compressed by an orbital cyst, while at the other, one finds minimalistic involvement that hardly affects the structure and function of the eye. In the fundus, the variability involves the size of the coloboma (anteroposterior and transverse extent) and the involvement of the optic disc and fovea. The visual acuity is affected when coloboma involves disc and fovea, or is complicated by occurrence of retinal detachment, choroidal neovascular membrane, cataract, amblyopia due to uncorrected refractive errors, etc. While the basic birth anomaly cannot be corrected, most of the complications listed above are correctable to a great extent. Current day surgical management of coloboma-related retinal detachments has evolved to yield consistently good results. Cataract surgery in these eyes can pose a challenge due to a combination of microphthalmos and relatively hard lenses, resulting in increased risk of intra-operative complications. Prophylactic laser retinopexy to the border of choroidal coloboma appears to be an attractive option for reducing risk of coloboma-related retinal detachment. However, a majority of the eyes have the optic disc within the choroidal coloboma, thus making it difficult to safely administer a complete treatment.

Ocular Findings in Infants with Congenital Toxoplasmosis after a Toxoplasmosis Outbreak

PURPOSE

We investigated the prevalence of ocular abnormalities in infants vertically exposed to Toxoplasma gondii infection during an outbreak in Santa Maria City, Brazil.

DESIGN

Consecutive case series.

PARTICIPANTS

A total of 187 infants were included.

METHODS

The infants were recruited from January 2018 to November 2019. All mothers were screened for syphilis and human immunodeficiency virus before delivery. Toxoplasmosis infection was confirmed in all mothers and infants based on the presence of serum anti-T. gondii immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies. All infants underwent an ophthalmologic examination; ocular abnormalities were documented using a wide-field digital imaging system. Neonatal cranial sonography or head computed tomography was performed in 181 infants, and the cerebrospinal fluid (CSF) was screened for anti-T. gondii IgG and IgM antibodies in 159 infants. Peripheral blood samples from 9 infants and their mothers were analyzed for the presence of T. gondii DNA by real-time polymerase chain reaction.

MAIN OUTCOME MEASURES

Ocular abnormalities associated with congenital toxoplasmosis.

RESULTS

A total of 187 infants were examined. Twenty-nine infants (15.5%) had congenital toxoplasmosis, of whom 19 (10.2%) had ocular abnormalities, including retinochoroiditis in 29 of 38 eyes (76.3%), optic nerve abnormalities in 5 eyes (13.2%), microphthalmia in 1 eye (2.6%), and cataract in 2 eyes (5.3%). Bilateral retinal choroidal lesions were found in 10 of 19 infants (52.6%). Nine eyes of 6 infants had active lesions, with retinal choroidal cellular infiltrates at the first examination. Thirteen (7.2%) of 181 infants screened presented with cerebral calcifications. Eighty-three percent of the screened infants were positive for anti-T. gondii IgG and negative for IgM antibodies in the CSF. Congenital toxoplasmosis was higher in mothers infected during the third pregnancy trimester, and maternal treatment during pregnancy was not associated with a lower rate of congenital toxoplasmosis.

CONCLUSIONS

High prevalence rates of clinical manifestations were observed in infants with congenital toxoplasmosis after a waterborne toxoplasmosis outbreak, the largest yet described. Cerebral calcifications were higher in infants with ocular abnormalities, and maternal infection during the third pregnancy trimester was associated with a higher rate of congenital toxoplasmosis independent of maternal treatment.

Multimodal Imaging in Ocular Toxoplasmosis

Multimodal imaging relies on combination of multiple imaging modalities to precisely delineate pathological changes in the posterior segment of the eye associated with a wide range of conditions. This combined application of fundus photography, optical coherence tomography, fundus reflectance/autofluorescence and fundus angiography (with fluorescein, indocyanine green and/or optical coherence tomography) is of great utility for assessment of patients with ocular toxoplasmosis. Multimodal imaging is helpful to characterize the typical pattern of toxoplasmic retinochoroiditis, with primary focal inflammatory involvement of the neurosensory retina, and secondary changes at the level of underlying choroid, retinal blood vessels, vitreous and even optic disc. It may also be valuable to document and follow local complications, including macular edema, vascular occlusions, and choroidal neovascularization, among others.

Intraretinal Cystoid Spaces in Regression of Punctate Inner Choroidopathy Lesions

PURPOSE

To describe and evaluate the intraretinal cystoid spaces (ICSs) in the eyes of punctate inner choroidopathy (PIC) patients.

METHODS

In this observational study, patients diagnosed with PIC were included and reviewed between December 2016 and November 2018. All patients underwent multimodal retinal imaging examinations.

RESULTS

Forty-one eyes of 26 patients diagnosed with PIC were included. ICSs were found in 13 eyes (31.7%) of 11 subjects. Statistical analysis revealed that except for spherical equivalent (P= .020), there were no significant difference between patients with ICSs and those with no ICSs at baseline. There were two types of ICSs according to the multimodal imaging findings. These two types of ICSs appeared with regressive PIC lesion and were stable during the follow-up period.

CONCLUSION

ICSs are commonly observed in PIC and they may be a sign of the restoration stage of the disease rather than a need for further clinical intervention.

NMNAT1-ASSOCIATED CONE-ROD DYSTROPHY: EVIDENCE FOR A SPECTRUM OF FOVEAL MALDEVELOPMENT

PURPOSE

To describe in detail the phenotype of two siblings with biallelic NMNAT1 mutations.

METHODS

A 4-year-old male patient (P1) and his 7-year-old sister (P2), product of a nonconsanguineous union of Egyptian ancestry, underwent a comprehensive ophthalmic examination, retinal imaging with spectral domain optical coherence tomography and near infrared (NIR) fundus autofluorescence (FAF), and full-field electroretinograms (ERG).

RESULTS

Patients had blurred vision and nystagmus at ∼3 years of age. P2 was hyperopic (+6D). Visual acuity in P1 was 20/100 at age 3 and remained at ∼20/125 at age 4; P2 visual acuity was 20/70 at age 4 and declined to ∼20/200 at age 7. ERGs recorded in P1 showed relatively large rod-mediated responses but nearly undetectable cone signals. There was foveal/parafoveal depigmentation. Spectral domain optical coherence tomography showed hypoplastic foveas, a thin outer nuclear layer centrally but normal thickness beyond the vascular arcades. At the foveal center, cone outer segments were absent and the outer nuclear layer was further hyporreflective. The inner retina was mostly within normal limits. There was central depigmentation on near infrared fundus autofluorescence. Biallelic mutations were identified in NMNAT1: One was previously reported (c.769 G>A; pGlu257Lys), and the other one (c.245T>C; pVal82Ala) was novel.

CONCLUSION

NMNAT1 mutations cause a consistent phenotype characterized by early-onset, progressive, cone>rod retinawide dysfunction and predominantly central abnormalities ranging from a hypoplastic to an atrophic fovea, supporting a critical role for NMNAT1 in central retinal development and maintenance. Relatively preserved inner retina and detectable photoreceptors may become therapeutic targets.

Macular Colobomata: Comparison of Clinical and Optical Coherence Tomography Features With Serologic Results

PURPOSE

To assess the correlation between the morphologic features and serology in eyes with macular colobomata (MC).

DESIGN

Retrospective comparative case series.

METHODS

Setting: Institutional.

STUDY POPULATION

Patients presenting with MC to the retina clinic over a period of 2 years (January 2016 to December 2017). Interventional/Observational Procedure: Color fundus and swept-source optical coherence tomography (SSOCT) features were reviewed and assessed in 3 groups based on the serum IgG results: positive for Toxoplasma, positive for cytomegalovirus (CMV), and serology negative.

MAIN OUTCOME MEASURE

Morphologic features on clinical and OCT-based examination.

RESULTS

A total of 49 eyes of 27 patients were recruited. The mean age was 24.8 ± 14.9 years (range 7-60 years). While the lesion size, the presence of satellite lesions, choroidal excavation, and choroidal lacunae (large choroidal vessels) on SSOCT differed significantly among the groups, pigmentation, retinal fibrosis, shape, retinal vessel pattern, and choroidal vessel visibility did not vary significantly. The lesions in CMV serology-positive cases were mostly solitary (n = 8/8), large (n = 5/8) and deeply excavated (n = 8/8). The lesions in Toxoplasma serology-positive cases were mostly flat to shallow (n = 18/26), medium-sized (n = 19/26), and either a solitary lesion (n = 17/26) or multiple satellite lesions (n = 9/26). The lesions in serology-negative cases were mostly small to medium (n = 13/15), solitary (n = 15/15), deeply excavated lesions (n = 11/15) with choroidal lacunae (n = 8/15).

CONCLUSIONS

The clinical and SSOCT features such as the lesion size, the presence of satellite lesions, choroidal excavation, and choroidal lacunae can provide a clue toward the etiology of macular colobomata.

Zika and the Eye: Pieces of a Puzzle

Zika virus (ZIKV) is an arbovirus mainly transmitted to humans by mosquitoes from Aedes genus. Other ways of transmission include the perinatal and sexual routes, blood transfusion, and laboratory exposure. Although the first human cases were registered in 1952 in African countries, outbreaks were only reported since 2007, when entire Pacific islands were affected. In March 2015, the first cases of ZIKV acute infection were notified in Brazil and, to date, 48 countries and territories in the Americas have confirmed local mosquito-borne transmission of ZIKV. Until 2015, ZIKV infection was thought to only cause asymptomatic or mild exanthematous febrile infections. However, after explosive ZIKV outbreaks in Polynesia and Latin American countries, it was confirmed that ZIKV could also lead to Guillain-Barré syndrome and congenital birth abnormalities. These abnormalities, which can include neurologic, ophthalmologic, audiologic, and skeletal findings, are now considered congenital Zika syndrome (CZS). Brain abnormalities in CZS include cerebral calcifications, malformations of cortical development, ventriculomegaly, lissencephaly, hypoplasia of the cerebellum and brainstem. The ocular findings, which are present in up to 70% of infants with CZS, include iris coloboma, lens subluxation, cataract, congenital glaucoma, and especially posterior segment findings. Loss of retinal pigment epithelium, the presence of a thin choroid, a perivascular choroidal inflammatory infiltrate, and atrophic changes within the optic nerve were seen in histologic analyses of eyes from deceased fetuses. To date, there is no ZIKV licensed vaccines or antiviral therapies are available for treatment. Preventive measures include individual protection from mosquito bites, control of mosquito populations and the use of barriers measures such as condoms during sexual intercourse or sexual abstinence for couples either at risk or after confirmed infection. A literature review based on studies that analyzed ocular findings in mothers and infants with CZS, with or without microcephaly, was conducted and a theoretical pathophysiologic explanation for ZIKV-ocular abnormalities was formulated.

Ocular abnormalities in congenital Zika syndrome: a case report, and review of the literature

Background

As the number of children with Zika virus-related complications grows, the long-term developmental trajectory and its effects on families are unknown. We present the first known case of congenital Zika syndrome seen at our institution with significant fundus findings.

Case presentation

A 3-day-old Hispanic baby girl presented with severe microcephaly of 24 cm and temperature instability at birth. Her mother had traveled to Honduras early in pregnancy and testing of amniotic fluid was positive for Zika virus via polymerase chain reaction. A dilated fundus examination was significant for bilateral severe colobomatous chorioretinal atrophy of the macula and pigmentary changes. Neonatal magnetic resonance imaging revealed diffuse lissencephaly with decreased brain volume, atrophic corpus callosum and brainstem, periventricular calcifications, and ventriculomegaly of the lateral ventricles.

Conclusions

Our patient, who presented with the first known case of congenital Zika syndrome in Northern Florida, demonstrated profound bilateral colobomatous chorioretinal atrophy of the macula. The ophthalmologic findings along with severe microcephaly emphasize the neurotropism of the Zika virus, and ultimately are indicative of poor developmental and visual prognosis for affected infants. With the increased prevalence of Zika virus, ophthalmologists should be aware of the associated findings and the importance of an eye-screening examination with a dilated fundus examination within 1 month of life of infants in which congenital Zika syndrome is suspected. A multidisciplinary care approach is essential for the care of affected infants and their families.

The use of handheld spectral domain optical coherence tomography in pediatric ophthalmology practice: Our experience of 975 infants and children

Purpose:

Optical coherence tomography (OCT) is an important imaging tool assessing retinal architecture. In this article, we report a single centers experience of using handheld spectral domain (SD)-OCT in a pediatric population using the Envisu 2300 (Bioptigen Inc., Research Triangle Park, NC, USA).

Methods:

We studied SD-OCT images from 975 patients imaged from January 2011 to December 2014. The variety of cases that underwent an SD-OCT was analyzed. Cases examples from different case scenarios were selected to showcase unique examples of many diseases.

Results:

Three hundred and sixty-eight infants (37.7%) were imaged for retinopathy of prematurity, 362 children (37.1%) underwent the test for evaluation of suboptimal vision or an unexplained vision loss, 126 children (12.9%) for evaluation of nystagmus or night blindness, 54 children (5.5%) for an intraocular tumor or a mass lesion such as retinoblastoma, and 65 children (6.7%) for other diseases of the pediatric retina. The unique findings in the retinal morphology seen with some of these diseases are discussed.

Conclusion:

The handheld SD-OCT is useful in the evaluation of the pediatric retinal diseases. The test is useful in the assessment of vision development in premature children, evaluation of unexplained vision loss and amblyopia, nystagmus and night blindness, and intraocular tumors (including retinoblastoma).

Optical coherence tomographic findings at the fixation point in a case of bilateral congenital macular coloboma

Background

Congenital macular coloboma is a rare ocular disease that consists of atrophic lesions in the macula with well-circumscribed borders. We report the findings of spectral domain optical coherence tomography (SD-OCT) at the fixation point in a case of bilateral macular coloboma.

Case report

The subject is a 4-year-old boy. He visited our hospital at age 1 year and 4 months for the evaluation of strabismus. The fundus examination of both eyes showed round-shaped sharply-demarcated atrophic lesions involving the macula with large choroidal vessels and bared sclera at the base. Immunologic tests including toxoplasmosis, rubella, varicella, herpes virus, and human T-cell leukemia virus were all negative. At age 4 years and 1 month, cycloplegic refraction showed insignificant refractive errors and his best corrected visual acuity was 0.6 bilaterally. The SD-OCT showed a crater-like depression accompanying atrophic neurosensory retina, and the absence of retinal pigment epithelium and choroid. Examination of the fixation behavior by visuscope showed steady fixation with an area 0.5° nasal to the nasal edge of the atrophic lesion bilaterally. The SD-OCT findings at fixation area showed remaining normal retinal structures involving inner segment-outer segment (IS/OS) junction line.

Conclusion

The findings of SD-OCT have been shown to be useful in the diagnosis of macular coloboma. In the fixation point, the structure of retina and choroid were well preserved.

Optical coherence tomography in pediatric ophthalmology: current roles and future directions

The application of existing optical coherence tomography (OCT) technology to the pediatric population is limited in both the design specification of the device and its hardware. However, the potential of OCT in the pediatric population has not been fully realized. The authors review the literature, highlighting the currently available spectral-domain OCT technology and summarizing the reported normal pediatric OCT parameters for retinal nerve fiber layer and macular thickness. They also review the pediatric ophthalmological conditions in which OCT has been used and discuss advancements in OCT design and their potential applications to the pediatric population. The use of OCT in pediatric populations is likely to increase greatly in the coming years, aiding clinical decision-making and providing new insights into pediatric disease pathophysiology.

Evaluation of cystoid change phenotypes in ocular toxoplasmosis using optical coherence tomography

Purpose

To present unique cystoid changes occurring in patients with ocular toxoplasmosis observed in spectral domain optical coherence tomography (OCT).

Methods

Forty-six patients (80 eyes) with a diagnosis of ocular toxoplasmosis, who underwent volume OCT examination between January 2005 and October 2012, were retrospectively collected. Review of clinical examination findings, fundus photographs, fluorescein angiograms (FA) and OCT image sets obtained at initial visits and follow-up. Qualitative and quantitative analyses of cystoid space phenotypes visualized using OCT.

Results

Of the 80 eyes included, 17 eyes (15 patients) demonstrated cystoid changes in the macula on OCT. Six eyes (7.5%) had cystoid macular edema (CME), 2 eyes (2.5%) had huge outer retinal cystoid space (HORC), 12 eyes (15%) had cystoid degeneration and additional 3 eyes (3.75%) had outer retinal tubulation due to age related macular degeneration. In one eye with HORC, the lesion was seen in the photoreceptor outer segment, accompanied by photoreceptor elongation and splitting. Three eyes presented with paravascular cystoid degeneration in the inner retina without other macular OCT abnormality.

Conclusions

In this study, different phenotypes of cystoid spaces seen in eyes with ocular toxoplasmosis using spectral domain OCT (SD-OCT) were demonstrated. CME presented as an uncommon feature, consistently with previous findings. Identification of rare morphological cystoid features (HORC with/without photoreceptor enlongation or splitting) on clinical examination had provided evidence to previous experimental models, which may also expand the clinical spectrum of the disease. Cystoid degeneration in the inner retina next to the retinal vessels in otherwise “normal” looking macula was observed, which may suggest more often clinical evaluation for those patients. Further studies are needed to verify the relevance of cystoid features seen on SD-OCT in assisting with the diagnosis and management of ocular toxoplasmosis.

Congenital hypertrophy of the retinal pigment epithelium: choroidal cavitation demonstrated on spectral-domain OCT

A patient with solitary congenital hypertrophy of the retinal pigment epithelium demonstrated a striking choroidal cavitation on spectral-domain optical coherence tomography (OCT). Although photoreceptor atrophy overlying congenital hypertrophy of the retinal pigment epithelium has been described on time-domain OCT, this patient manifested a previously unrecognized tomographic feature.

Intraoperative OCT of bilateral macular coloboma in a child with Down syndrome

A 3-year-old girl with Down syndrome presented with a macular lesion in both eyes. With intraoperative optical coherence tomography confirmation, the patient was diagnosed as having bilateral macular coloboma. These findings were previously reported in two patients with Down syndrome. The documentation of similar findings in three separate patients suggests that macular coloboma may be a rare ophthalmic pathology associated with Down syndrome. Moreover, optical coherence tomography imaging may be a useful adjunct in diagnosing macular coloboma in the pediatric population.

Evaluation of spectral domain and time domain optical coherence tomography findings in toxoplasmic retinochoroiditis

PURPOSE

To investigate spectral domain optical coherence tomography (SD-OCT) findings and compare them with time domain (TD)-OCT imaging of macula and retinochoroiditis lesions of patients with toxoplasmosis.

DESIGN

Prospective cross-sectional study.

METHODS

Ten eyes of 10 patients with active toxoplasmic retinochoroiditis were included. Morphologic features from the macula and retinochoroiditis lesions were obtained at baseline and at 6-week follow up. Scan acquisition protocols for TD-OCT included raster and radial lines through the retinochoroiditis lesion, fast macular, and a linear scan from the lesion to the fovea, whereas the acquisition protocols for SD-OCT also included horizontal volume scans at the lesion site and at the macula. Thickness measurements obtained by SD-OCT were analyzed.

RESULTS

At baseline, macular serous retinal detachment was observed in five patients; two of them only seen by SD-OCT. Retinochoroidal lesions were 4260 μm distant from the fovea on average (R = 681-7130) and this distance had an indirect correlation to the presence of macular detachment. Epiretinal membrane and vitreo-macular traction were also observed. The posterior hyaloid was not identified in four patients by TD-OCT and only in one by SD-OCT at baseline. Perilesional subretinal fluid was observed in two patients. The median retinal thickness significantly decreased at the retinochoroiditis lesion (P = 0.0004), and all the patients remained with disorganized retinal layers reflectivity at follow up.

CONCLUSION

SD-OCT is a useful tool in the diagnosis of macular changes related with toxoplasmic retinochoroiditis. SD-OCT is superior in evaluating retinal changes associated with ocular toxoplasmosis.