US and color Doppler imaging of ocular and orbital disease in the pediatric age group

Imaging the pediatric retina: An overview

Recent decade has seen a shift in the causes of childhood blinding diseases from anterior segment to retinal disease in both developed and developing countries. The common retinal disorders are retinopathy of prematurity and vitreoretinal infections in neonates, congenital anomalies in infants, and vascular retinopathies including type 1 diabetes, tumors, and inherited retinal diseases in children (up to 12 years). Retinal imaging helps in diagnosis, management, follow up and prognostication in all these disorders. These imaging modalities include fundus photography, fluorescein angiography, ultrasonography, retinal vascular and structural studies, and electrodiagnosis. Over the decades there has been tremendous advances both in design (compact, multifunctional, tele-consult capable) and technology (wide- and ultra-wide field and noninvasive retinal angiography). These new advances have application in most of the pediatric retinal diseases though at most times the designs of new devices have remained confined to use in adults. Poor patient cooperation and insufficient attention span in children demand careful crafting of the devices. The newer attempts of hand-held retinal diagnostic devices are welcome additions in this direction. While much has been done, there is still much to do in the coming years. One of the compelling and immediate needs is the pediatric version of optical coherence tomography angiography. These needs and demands would increase many folds in future. A sound policy could be the simultaneous development of adult and pediatric version of all ophthalmic diagnostic devices, coupled with capacity building of trained medical personnel.

Multi-parametric magnetic resonance imaging characterization of orbital lesions: a triple blind study

Background: Multi-parametric MRI used for preoperative assessment of orbital lesions does not routinely include DCE-MRI, since its accuracy in differential diagnosis of orbital mass is still under debate. Aim of this study is to characterize orbital lesions by multi-parametric MRI, analysing the incremental predictive value of DCE-MRI in differential diagnosis of orbital lesions.Methods: In this prospective triple-blind study, 43 consecutive patients with unilateral orbital lesion underwent conventional multimodal MRI and DCE-MRI before biopsy in a tertiary referral centre. Pre-operative MRI examination including conventional unenhanced MRI protocol, DWI with ADC maps, static CE 3D-T1 w and dynamic CE T1 w sequences, was performed within 1 week from surgery (anterior/lateral orbitotomy depending on location of the lesion, to carry out incisional/excisional biopsy).Results: Comparison between conventional T1 w/T2 w, DWI, CE 3D-T1 w and DCE-MRI groups showed a statistically significant difference in scores distribution (p < .001). Statistically significant difference was found between conventional T1 w/T2 w and DWI (p < .005), as well as between DWI and CE 3D-T1 w (p < .001). Conversely, no significant difference was found between CE 3D-T1 w and DCE (p < .005).Conclusions and Relevance: This study confirmed the positive effect of DWI and CE 3D-T1 w on orbital lesions diagnosis when added to conventional T1 w/T2 w sequences, whereas no substantial impact on diagnostic performance was observed with the further addition of DCE-MRI. DCE does not strongly influence diagnostic performance and inter-rater agreement in characterizing orbital lesions; therefore, it should be recommended in selected patients whose assessment of flow dynamics is particularly useful for management.Abbreviations: US = ultrasonography; MRI = magnetic resonance imaging; CT = computed tomography; STIR = Short-TI Inversion Recovery; DWI = diffusion weighted imaging; DCE-MRI = dynamic contrast-enhanced MRI; SE = Spin-Echo; TSE = Turbo Spin-Echo; THRIVE = T1-weighted high resolution Isotropic Volume Examination (dynamic contrast-enhanced ultrafast spoiled gradient echo); ROI = regions of interest; IRR = inter-rater reliability; TIC = time-intensity curve.

Ocular ultrasonography focused on the posterior eye segment: what radiologists should know

Abstract

Ocular B-mode ultrasonography (US) is an important adjuvant for the clinical assessment of a variety of ocular diseases. When ophthalmoscopy is not possible, mainly due to opacification of the transparent media (e.g., mature cataract or vitreous haemorrhage), US can guide the ophthalmologist in diagnosing disease and choosing treatment. The superficial location and cystic structure of the eye make US ideal for imaging of the eye. Moreover, dynamic study helps distinguish between various conditions that would otherwise be difficult to differentiate in some clinical setting, such as vitreous, retinal, and choroidal detachment. US is also good technique for detecting other pathologic conditions such as lens dislocation, vitreous haemorrhage, asteroid hyalosis, optic disc drusen, and tumors (e.g., choroidal melanoma, metastases, hemangioma). An understanding of the basic anatomy of the eye, the US technique, and common entities that affect the ocular globe will allow radiologists to offer this valuable imaging modality to patients and referring clinicians. This article focuses on the US anatomy and pathologic conditions that affect the posterior ocular segment.

Teaching points

• US is specially indicated when ocular fundus cannot be assessed on ophthalmoscopy.

• Multipurpose equipment with high-frequency transducers is optimal for imaging the eye.

• Ultrasound can reliably depict ocular anatomy and pathology as detachments and tumours.

• Dynamic examination is vital for distinguishing certain pathologic conditions as detachments.

Electronic supplementary material

The online version of this article (doi:10.1007/s13244-016-0471-z) contains supplementary material, which is available to authorized users.

Ocular ultrasound as an easy applicable tool for detection of Terson's syndrome after aneurysmal subarachnoid hemorrhage

Introduction

Intraocular hemorrhage in patients suffering from aneurysmal subarachnoid hemorrhage is known as Terson's syndrome and is an underestimated but common pathology. We therefore designed a prospective single-blinded study to evaluate the validity of ocular ultrasound compared to the gold standard indirect funduscopy in the diagnosis of Terson's syndrome.

Material and Methods

Fifty-two patients (104 eyes in total) suffering from aneurysmal subarachnoid hemorrhage were enrolled in this study. Two investigators independently performed a single-blinded ocular ultrasound using a standard intensive care ultrasound system to detect an intraocular hemorrhage. Indirect funduscopy following iatrogenic mydriasis served as the gold standard for confirmation or exclusion of an intraocular hemorrhage. Statistical analyses were performed to evaluate the sensitivity and specificity, positive and negative predictive values of the method as well as the learning curve of ocular ultrasound.

Results

Indirect funduscopy detected Terson's syndrome in 11 of 52 (21.2%) respectively in 21 of 104 (20.2%) eyes in patients suffering from subarachnoid hemorrhage. Sensitivity and specificity increased with the number of ocular ultrasound examinations for both investigators, reaching 81.8% and 100% respectively. Positive and negative predictive values were different for both investigators (63.6% vs. 100% positive and 100% vs. 95.7% negative) but were both correlated to the amount of intraocular hemorrhage. A low Glasgow Coma scale (p = 0.015) and high Hunt & Hess grade (p = 0.003) was associated with a higher rate of Terson's syndrome.

Conclusions

Ocular ultrasound using standard ultrasound equipment has been confirmed as a reliable, easy-to-handle bedside screening tool for detecting Terson's syndrome. Nevertheless funduscopy remains the gold standard to detect Terson's syndrome.

Retrobulbar magnetic resonance angiography using binomial off-resonant rectangular (BORR) pulse

PURPOSE

Applying a newly developed binomial off-resonant rectangular (BORR) pulse method for high resolution three-dimensional MR angiography (MRA) on retrobulbar ocular vessels, which has not been possible with routine MRA due to background fatty tissues.

METHODS

BORR pulse was implemented in a gradient echo sequence by replacing the original excitation pulse, and were optimized for robust orbital fat suppression. Several other MRA methods, with or without fat suppression, were also compared, including time-of-flight, contrast enhanced MRA, and hybrid of opposite-contrast MRA. Nine healthy subjects participated with written informed consents. To reduce eye motion, the subjects were instructed to casually stare at a projected cross during each MRA scan. Major vessels were evaluated by three independent radiologists using a 4-point scale.

RESULTS

The BORR method yielded the best MRA results for retrobulbar vessels without contrast enhancement, significantly superior than other MRA methods. BORR results had significantly higher visibility scores than all other methods for small vessels.

CONCLUSION

We have successfully revealed orbital vessels in retrobulbar space for the first time using MRA, by using the BORR pulse method. With a clear depiction of the vasculature without the need for contrast enhancement, our method has the potential to provide important diagnostic information for ocular vascular diseases.

Colour Doppler ultrasound imaging findings in paediatric periocular and orbital haemangiomas

PURPOSE

To evaluate the combined grey-scale ultrasonography (US) and colour Doppler imaging (CDI) as the first and primary imaging modalities in diagnosing paediatric orbital haemangiomas.

METHODS

The charts of 20 consecutive children with a periorbital mass echographically diagnosed as a haemangioma between January 2004 and June 2009 in the Tel-Aviv Sourasky Medical Center were reviewed. Data on demographic details, clinical findings, US and CDI characteristics, treatment and outcome were retrieved.

RESULTS

Twelve (60%) haemangiomas were located on the upper eyelid, five in the lower eyelid (25%) and three in the medial cantus (15%). The tumour resolved completely in 10 children (50%) and in 10 children (50%) partial resolution was documented. Seven (35%) patients underwent treatment (intralesional or oral steroids or propranolol). Grey-scale US depicted a solid-tissue mass with low internal echogenicity. Mean haemangioma volume was 1.33 cm(3) . Colour Doppler imaging demonstrated intralesional flow with a mean peak systolic velocity of 15.2 cm per second and a mean resistance index of 0.51. All US and CDI examinations were carried out on alert children and no sedation or general anaesthesia was needed. During mean follow-up time of 23 months, no child required any additional imaging or diagnostic procedures to confirm the diagnosis.

CONCLUSION

Combined US and CDI are suggested as the first imaging modalities in cases with a suspected diagnosis of periocular and orbital capillary haemangioma.

US and MRI of pediatric ocular masses with histopathological correlation

We review our experience with unusual ocular pathologies, some mimicking retinoblastoma, that were referred to our institution during the past two decades. After presenting the imaging anatomy of the normal eye, we discuss pertinent clinical and pathological features, and illustrate the US and MRI appearance of retinoblastoma, medulloepithelioma, uveal melanoma, persistent fetal vasculature, Coats disease, corneal dermoid, retinal dysplasia and toxocara granuloma. Features useful in discriminating among these entities are emphasized.

From the archives of the AFIP: Pediatric orbit tumors and tumorlike lesions: neuroepithelial lesions of the ocular globe and optic nerve

Tumors and tumorlike lesions of the globe and optic nerve in children represent a different histologic spectrum than in adults; the imaging appearances of these lesions reflect their pathologic features. Retinoblastoma is a tumor of infancy and the most common intraocular tumor in children. There are heritable and nonheritable forms. The most common clinical finding is leukocoria. The differential diagnoses of this sign include several nonneoplastic lesions: Persistent hyperplastic primary vitreous is a congenital persistence of an embryonic structure causing a retrolental mass. The primitive vasculature may produce a septum in the posterior chamber. Coats disease is a vascular malformation of the retina that produces a lipoproteinaceous subretinal exudate. The vascular malformation enhances with intravenous contrast material, and the fat-containing subretinal exudate does not. Larval endophthalmitis is a granulomatous reaction to the dead or dying larvae of Toxocara canis or T. cati. The most important feature that allows differentiation of retinoblastoma from these so-called pseudoretinoblastomas is the presence of calcification in the former. Medulloepithelioma has two histologic forms; the teratoid type may contain calcifications, but it usually arises anteriorly from the ciliary body rather than posteriorly from the retina. Optic nerve glioma is the most common tumor of the optic nerve in children and is frequently associated with neurofibromatosis type 1. These gliomas are usually pilocytic astrocytomas and cause fusiform enlargement of the nerve.

Intraorbital and periorbital tumors in children--value of ultrasound and color Doppler imaging in the differential diagnosis

PURPOSE

To evaluate the role of ultrasonography (US) and color Doppler imaging (CDI) in the diagnosis of orbital tumors in children.

DESIGN

Retrospective nonrandomized interventional case series.

METHODS

This study included 42 children with intraorbital and periorbital tumors who were evaluated in our clinic. All children underwent a complete clinical evaluation as well as orbital US and CDI. The children then underwent operation or were followed up, based on the clinical diagnosis and the findings on the imaging modalities.

RESULTS

The mean age of the patients at diagnosis was 22.5 months (range 2 weeks-14 years old). Eighteen patients (12 female and 6 male) were diagnosed with hemangioma based on the findings in US and CDI; 16 patients (9 female and 7 male) were diagnosed with dermoid, 5 patients (4 female and 1 male) with lymphangioma, 2 patients with rhabdomyosarcoma, and 1 patient with a subperiostal abscess. Twenty-two patients underwent operation, and the diagnosis was confirmed on pathology. Twenty patients did not undergo operation and continued to be followed up in the clinic (mean follow-up period 38.2 months). The disease course in all patients who did not undergo operation was consistent with the working diagnosis.

CONCLUSION

Both US and CDI are useful modalities in the diagnosis of intraorbital and periorbital tumors in the pediatric age group.

Imaging of orbital disorders in pediatric patients

The spectrum of orbital lesions occurring in childhood is wide, including a variety of both benign and malignant disorders. Although physical examination and fundoscopy may aid in establishing the diagnosis of retro-ocular lesions, imaging remains a critical step in the evaluation of the pediatric orbit. Ultrasonography, CT, and MR imaging are the primary modalities for the evaluation of the diseased orbit, and careful observation of the characteristic radiological features usually leads to correct diagnosis; however, some of the lesions look very similar and are difficult to differentiate from each other. The purpose of this article is to review the common and unusual entities that may involve the pediatric orbit, to describe the radiological features, and to evaluate the efficacy of US, CT, and MRI in the diagnosis and management of these conditions.

Orbital vascular lesions. Role of imaging

Vascular lesions represent an important subgroup of orbital abnormalities; however, there is much controversy regarding their pathophysiology and nomenclature. Attempts at resolution of some of the issues have resulted in changes of names of some of the lesions (e.g., lymphangioma to venolymphatic malformation). Imaging plays an important role in delineation and characterization of these lesions. A radiologist informed about the pathophysiology and attentive to the internal architecture of the lesions shown on images, particularly MR images, often can predict the histologic diagnosis. Imaging information helps clarify some of the controversies surrounding these lesions.

Ultrasonographic diagnosis of persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous in two dogs

Ultrasonography was performed on a Basset hound and a Doberman clinically suspected of persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous. In both dogs, hyperechoic lenses with a triangular-shaped echodense structure retrolentally were visible, and a very thin hyperechoic strand was seen penetrating the anechoic vitreous from this retrolental tissue to the area of the optic nerve. Using color Doppler imaging, blood flow was evident in parts of the retina in both dogs. With power Doppler imaging there was blood flow in the lens and hyperechoic strand of the Basset hound on the first examination; whereas, on re-examination 5 months later, this was not found. Other abnormalities, such as retinal detachment, endophthalmitis, vitreous hemorrhage, microphthalmia, and posterior neoplasia could be excluded.