UNASSIGNED: This work aims to report the challenging diagnosis, treatment, and follow-up of a patient with persistent fetal vasculature (PFV) and retinoblastoma (RB).
UNASSIGNED: A 22-month-old boy presented with unilateral RB stage VB in the right eye and PFV in both eyes. The patient was treated with transpupillary laser ablation and systemic chemotherapy.
UNASSIGNED: Treatment resulted in complete tumor regression. Two years after the last systemic chemotherapy treatment, magnetic resonance imaging (MRI) showed increased signal intensity with progressive optic nerve enhancement, where intraneural malignancy could not be excluded. Enucleation of the right eye was performed. Histopathologic review showed no residual active malignancy in the enucleated globe.
UNASSIGNED: This case demonstrates the importance of a thorough clinical examination to establish the correct diagnosis and to rule out RB before any surgery. This case also highlights the importance of regular follow-ups after tumor regression with full a ophthalmologic examination, B-scan, and periodic MRI.

OBJECTIVE: To investigate the distribution of pseudoretinoblastoma (PSRB) cases based on gender, age, and laterality.
METHODS: The clinical records of 607 patients (851 eyes) who were referred for diagnosis of retinoblastoma or simulating conditions between October 1998 and May 2021 were retrospectively evaluated. Patients were stratified by age as follows: ≤1 year, >1-3 years, >3-5 years, and >5 years.
RESULTS: Of 190/607 PSRB patients, 129 (67.9%) were males and 61 (32.1%) females (p = 0.001). The 3 most common diagnoses in males were Coats disease (20.2%), persistent fetal vasculature (PFV, 14.0%), and chorioretinal coloboma (6.2%). In females, the 3 most common diagnoses included PFV (21.3%), retinal dysplasia, congenital glaucoma, and combined hamartoma (each 6.6%). PFV was the most common diagnosis in ≤1 year old patient group (26.6%). Coats disease and PFV were the most common diagnoses in >1-3 years old patient group (each 16.7%). Coats disease was the most common diagnosis in >3-5 years old (30.8%) and >5 years old patient groups (13.1%). PSRBs were unilateral in 121/190 (63.7%) patients. Coats disease usually presented unilaterally (p < 0.001) while PFV, optic nerve head drusen, and retinopathy of prematurity as bilateral diseases (p = 0.019, p = 0.001, and p = 0.001 respectively).
CONCLUSIONS: PSRB diagnoses show differences depending on gender, age, and laterality. In our study, the most common PSRB lesions were Coats disease in males and PFV in females. PFV was the most frequent diagnosis in ≤3 years and Coats disease in >3 years of age groups. Coats disease and PFV were the most common unilateral and bilateral PSRB diagnoses respectively.

OBJECTIVE: To study the different types and frequency of pseudoretinoblastoma (pseudoRB) lesions who present to a retinoblastoma centre due to concern that the condition may be retinoblastoma.
METHODS: A retrospective chart review of 341 patients presenting sporadically to the Royal London Hospital from January 2009 to December 2018.
RESULTS: 220 patients (65%) were confirmed to have retinoblastoma, while 121 (35%) had pseudoRB. There were 23 differential diagnoses in total. The top 3 differential diagnoses were Coats\' disease (34%), Persistent Foetal Vasculature (PFV) (17%) and Combined Hamartoma of Retina and Retinal Pigment Epithelium (CHR-RPE) (13%). PseudoRBs differed with age at presentation. Under the age of 1 (n = 42), the most likely pseudoRB conditions were PFV (36%), Coats\' disease (17%) and CHR-RPE (12%). These conditions were also the most common simulating conditions between the ages of 1 and 2 (n = 21), but Coats\' disease was the most common in this age group (52%), followed by CHR-RPE (19%) and PFV (14%). Between the ages of 2 and 5 (n = 32), Coats\' disease remained the most common (44%) pseudoRB lesion followed by CHR-RPE (13%), or PFV, Retinal Astrocytic Hamartoma (RAH), familial exudative vitreoretinopathy (FEVR) (all 6.3%). Over the age of 5 (n = 26), pseudoRBs were most likely to be Coats\' disease (35%), RAH (12%), Uveitis, CHR-RPE, FEVR (all 7.7%).
CONCLUSIONS: 35% of suspected retinoblastoma cases are pseudoRB conditions. Overall, Coats\' disease is the most common pseudoRB condition, followed by PFV. Hamartomas (CHR-RPE & RAH) are more prevalent in this cohort, reflecting improvements in diagnostic accuracy from referring ophthalmologists.

Retinoblastoma mimickers, or pseudoretinoblastoma, are conditions that show similarities with the pediatric cancer retinoblastoma. However, false-positive retinoblastoma diagnosis can cause mistreatment, while false-negative diagnosis can cause life-threatening treatment delay. The purpose of this study is to identify the MR imaging features that best differentiate between retinoblastoma and the most common pseudoretinoblastoma diagnoses: Coats\' disease and persistent fetal vasculature (PFV). Here, six expert radiologists performed retrospective assessments (blinded for diagnosis) of MR images of patients with a final diagnosis based on histopathology or clinical follow-up. Associations between 20 predefined imaging features and diagnosis were assessed with exact tests corrected for multiple hypothesis testing. Sixty-six patients were included, of which 33 (50%) were retinoblastoma and 33 (50%) pseudoretinoblastoma patients. A larger eye size, vitreous seeding, and sharp-V-shaped retinal detachment were almost exclusively found in retinoblastoma (p < 0.001-0.022, specificity 93-97%). Features that were almost exclusively found in pseudoretinoblastoma included smaller eye size, ciliary/lens deformations, optic nerve atrophy, a central stalk between optic disc and lens, Y-shaped retinal detachment, and absence of calcifications (p < 0.001-0.022, specificity 91-100%). Additionally, three newly identified imaging features were exclusively present in pseudoretinoblastoma: intraretinal macrocysts (p < 0.001, 38% [9/24] in Coats\' disease and 20% [2/10] in PFV), contrast enhancement outside the solid lesion (p < 0.001, 30% [7/23] in Coats\' disease and 57% [4/7] in PFV), and enhancing subfoveal nodules (38% [9/24] in Coats\' disease). An assessment strategy was proposed for MR imaging differentiation between retinoblastoma and pseudoretinoblastoma, including three newly identified differentiating MR imaging features.

OBJECTIVE: To describe pathological features and determine the types and frequency of pseudoretinoblastoma simulating retinoblastoma in 70 enucleated eyes.
METHODS: Retrospective histopathologic analysis of consecutively enucleated eyes for presumed intraocular retinoblastoma during the past 11 years in the Second People\'s Hospital of Yunnan Province in China.
RESULTS: 9 of the 70 cases were found to be pseudoretinoblastoma on histological analysis. 4 cases were Coat\'s disease, 2 cases were uveitis and the rest 3 cases were respectively identified as vitreous hemorrhage, toxocariasis and retinal dysplasia. Clinical features and pathological features of these cases were described in detail.
CONCLUSIONS: Coat\'s disease accounted for the most common conditions (44.5%) of pseudoretinoblastoma, uveitis (22.2%) accounted for less common conditions, toxocariasis (11.1%), vitreous hemorrhage (11.1%) and retinal dysplasia (11.1%) presented in a sporadic form in our pseudoretinoblastoma series. They have distinctive histopathological features to differentiate from retinoblastoma.

Perinatal inflammatory retinal diseases and intrauterine retinal maldevelopments are mistaken for retinoblastoma as often as in 8-16% of cases.
OBJECTIVE: To analyze the infectious status in children with retinoblastoma and pseudoretinoblastoma at different ages.
METHODS: A total of 47 retinoblastoma suspects aged 4-69 months were enrolled. Pseudoretinoblastoma (inflammatory retinal diseases and intrauterine maldevelopments of the retina) was detected in 14 children (group 1), retinoblastoma - in 33 children (group 2). In each group, two subgroups were identified: \'a\' - children under 12 months of age (1a - 5 patients, 2a - 10 patients) and \'b\'- children over 12 months of age (1b - 9 patients, 2b - 23 patients). Their blood sera were examined for antibodies to herpes simplex virus types 1 and 2, cytomegalovirus, Epstein-Barr virus, toxoplasma, toxocara, chlamydia, and mycoplasma (enzyme-linked immunosorbent assay).
RESULTS: According to serological screening, all patients from group 1a (children under 12 months of age with pseudoretinoblastoma), in contrast to other groups, were infected perinatally with cytomegalovirus infection. All 47 patients were seronegative to toxoplasma. Toxocara infection was identified in children over 12 months of age: in 3 out of 9 patients with pseudoretinoblastoma and in 2 out of 23 patients with retinoblastoma (p>0.05). Markers of Epstein-Barr viral activity were detected only in 3 retinoblastoma children over 12 months of age.
CONCLUSIONS: The results suggest that cytomegalovirus infection plays the leading role in the development of perinatal eye pathology, which, in infants, is clinically similar to retinoblastoma. In children over 12 months of age we found no serological signs that could be regarded as specific of either retinoblastoma, or pseudoretinoblastoma. The only thing worth paying attention to is the activation of Epstein-Barr virus infection in children over 12 months of age with retinoblastoma.
Перинатальные воспалительные заболевания сетчатки и пороки ее внутриутробного развития в 8-16% случаев ошибочно трактуются как ретинобластома. Цель - анализ инфекционного статуса детей с ретинобластомой и \'псевдоретинобластомами\' в зависимости от возраста. Материал и методы. Обследовано 47 детей в возрасте от 4 до 69 мес с подозрением на ретинобластому. \'Псевдоретинобластомы\' (воспалительные заболевания сетчатки, пороки развития) выявлены у 14 детей (1-я группа), ретинобластома - у 33 (2-я группа). В каждой группе выделили 2 подгруппы: \'а\' - дети в возрасте до 12 мес включительно (1а - 5, 2а - 10 пациентов), \'б\' - дети старше 1 года (1б - 9, 2б - 23 пациента). В сыворотках крови определяли антитела к вирусу простого герпеса 1, 2-го типа, цитомегаловирусу, вирусу Эпштейна-Барр, токсоплазме, токсокаре, хламидиям, микоплазме, уреаплазме (иммуноферментный анализ). Результаты. По данным серологического обследования, все дети с \'псевдоретинобластомами\' младше 12 мес перенесли перинатальную цитомегаловирусную инфекцию в отличие от пациентов 1-й группы старше 12 мес и детей с ретинобластомой. Все 47 больных оказались серонегативны к токсоплазме. Инфицированность токсокарой установлена у детей старше 12 мес: у 3 из 9 с псевдоретинобластомами и у 2 из 23 с ретинобластомой (p>0,05). Маркеры активности вируса Эпштейна-Барр выявлены только у 3 детей с ретинобластомой старше 12 мес. Заключение. Полученные результаты позволяют предположить ведущую роль цитомегаловируса в развитии перинатальной патологии глаз, которая клинически у детей грудного возраста сходна с ретинобластомой. У детей старше 1 года не выявлено серологических признаков, специфичных для ретинобластомы и \'псевдоретинобластом\'. Обращает на себя внимание лишь активация вируса Эпштейна-Барр у детей с ретинобластомой старше 1 года.

BACKGROUND: Incontinentia pigmenti is a rare X-linked dominant syndrome caused by mutation in the NEMO/IKKgamma gene, and characterized by a spectrum of cutaneous, ocular, neurologic and dental abnormalities. In the eye, findings include retinal vascular non-perfusion, occasionally with traction retinal detachment, retinal fibrosis, and retinal pigment epithelium defects. These findings can resemble retinoblastoma, especially when vitreoretinal fibrosis produces leukocoria.
METHODS: A 2-month-old girl born full-term presented with leukocoria, suspicious for retinoblastoma. She was found to have an ischemic retrolental fibrovascular retinal detachment. In addition, there was linear cutaneous hyperpigmentation, diagnostic of incontinentia pigmenti.
CONCLUSIONS: Retinoblastoma can be a challenge to diagnose. There are numerous simulating lesions that can present with leukocoria and retinal detachment, including incontinentia pigmenti. Recognition of the cutaneous features of incontinentia pigmenti contributes to early detection of related ophthalmologic, neurologic and dental abnormalities.