Download Neurosonology: a potential diagnostic tool in central retinal vein

INTERNATIONAL JOURNAL OF
CLINICAL NEUROSCIENCES
MENTAL HEALTH
AND
CASE REPORT
Neurosonology: a potential diagnostic tool in central
retinal vein occlusion
Ana Inês Martins1, João Sargento-Freitas1,2,4, Fernando Silva1,2, José Beato-Coelho1, Gustavo C. Santo1, Cláudia
Farinha3, João Figueira3, and Luís Cunha1,4
Special Issue on Controversies in Neurology. From the 10th World Congress on Controversies in Neurology (CONy), Lisbon, Portugal. 17–20 March 2016.
Abstract
Introduction: Central retinal vein occlusion (CRVO) is a common vascular retinal pathology. It produces a subacute monocular severe visual loss, usually painless. Retinal and iris neovascularization can result in vitreous hemorrhages, neovascular
glaucoma and tractional retinal detachment. The diagnosis is clinically-based, through funduscopic exam, and supported by
fluorescein angiography, an invasive technique requiring intravenous contrast administration. The diagnosis becomes harder
in the presence of local complications preventing ocular fundus observation, as hemovitreous, sometimes requiring clarifying
surgical intervention. Neurosonology, a non-invasive and safe technique, has not yet been pointed out as a definite diagnostic
tool in CRVO.
Case Report: An 82-years-old female with known and poorly controlled essential hypertension and type 2 diabetes mellitus,
developed a subacute visual acuity impairment in her left eye, allowing solely hand movements visualization. Ophthalmoscopy reveled a total hemovitreous of the left eye. Ocular echography did not show any other lesions. Differential diagnosis stood
between CRVO and ocular arterial ischemic syndrome. Transorbital colour coded Doppler identified a preserved left ophthalmic artery and a reverberant flow in the central retinal vein, suggesting CRVO. The patient underwent pars plana vitrectomy
associated to endolaser as management of this secondary complication of CRVO.
Discussion: The present clinical case underlines a potential new neurossonologic application, as a diagnostic tool in CRVO,
particularly useful when ocular fundus cannot be properly visualized.
Keywords: Neurosonology, Central retinal vein occlusion, Hemovitreous.
Neurology Department, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
1
Neurosonology Laboratory, Neurology Department, Centro Hospitalar e
Universitário de Coimbra, Coimbra, Portugal
2
Ophthalmology Department, Centro Hospitalar e Universitário de Coimbra,
Coimbra, Portugal
Citation: Martins et al. Neurosonology: a potential diagnostic tool in central
retinal vein occlusion. International Journal of Clinical Neurosciences and
Mental Health 2016; 3(Suppl. 1):S14
DOI: https://doi.org/10.21035/ijcnmh.2016.3(Suppl.1).S14
3
Published: 23 December 2016
Faculdade de Medicina, Universidade de Coimbra, Coimbra, Portugal
4
Correspondence: João Sargento-Freitas
Centro Hospitalar e Universitário de Coimbra, Praceta Mota Pinto, 3000-075 Coimbra,
Portugal
Email: [email protected]
Open Access Publication
Available at http://ijcnmh.arc-publishing.org
© 2016 Martins et al. This is an open access article distributed under the Creative Commons
Attribution License, which permits unrestricted use, distribution, and reproduction in any medium,
provided the original work is properly cited.
2
Neurosonoloy in central retinal vein occlusion
Introduction
Central retinal vein occlusion (CRVO), a potentially disabling disease, is the second most common retinal vascular
disorder after diabetic retinopathy [1]. There is an association with older age, smoking history, hypertension, dyslipidemia and diabetes [2]. It has been suggested that venous occlusion leads to hypoxia and a subsequent ischemic
state, originating macular edema and retinal neovascularization [3]. The latter may lead to vitreous hemorrhages,
neovascular glaucoma and tractional retinal detachment
[4]. Clinically, there is a subacute visual loss, progressive
and usually painless. Diagnosis is based on clinical assessment, made by funduscopic examination and supported by
fluorescein angiography, which is an invasive technique
requiring intravenous contrast administration [5]. However, this diagnostic tool becomes useless in the presence
of local complications preventing an accurate fundus visualization, as hemovitreous, sometimes requiring clarifying
surgical intervention. Neurosonology, a non-invasive and
safe technique, has not yet been established as a diagnostic
tool in CRVO.
Case Report
We present a 82-year-old woman who developed subacute, painless visual acuity impairment of her left eye. She
denied headaches, ocular or cranial trauma.
Her medical history included type 2 diabetes mellitus
with a poor metabolic control, and essential hypertension,
poorly controlled although she had been taking an angiotensin-converting enzyme inhibitor. The patient had never smoked and had residual alcohol consumption.
Physical examination revealed high blood pressure
(175/89 mmHg). Her body mass index was 32.1 kg/m2.
She had severe impairment of visual acuity in her left eye,
allowing solely hand movements visualization. No other
neurologic deficits were identified. Intraocular pressure
values were within normal range. Basic laboratory testing
was normal. Ophthalmoscopy showed a complete hemovitreous of the left eye and an otherwise normal disc, macula
and fundus at her right eye. Differential diagnosis stood
between neovascularization related to hemovitreous due
to CRVO or ocular arterial ischemic syndrome. The patient was then presented for neurosonologic examination.
Carotid and vertebral evaluation did not have hemodynamically significant arterial stenoses, bilaterally. There
were also no hemodynamically significant stenoses in intracranial vessels. Transorbital B-mode (General Electrics
Logiq 7 with a linear 11MHz probe) ultrasound confirmed
the hemoviterous of the left eye without any further
pathological changes. Transorbital colour coded Doppler
(TCCD) identified a preserved flow in the right superior
ophthalmic vein, right central retinal artery and in the
right central retinal vein. Both left superior ophthalmic
vein and left central retinal artery (Figure 1) also present-
Figure 1. Left central retinal vein EcoDoppler: reverberant flow.
ARC Publishing
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Martins et al.
ed with a normal flow. However, left central retinal vein
presented with a reverberant flow (Figure 1). This finding
allowed diagnosis of CRVO with an associated complication—hemovitreous. The patient underwent pars plana
vitrectomy associated to endolaser as management of this
secondary complication of CRVO.
Discussion
CRVO is a common retinal vascular pathology that can affect people of any age but is more common in the elderly.
In the presence of local complications such as hemovitreous, which sometimes can totally prevent fundus visualization, the correct diagnosis and subsequent treatment
may become compromised. Performing a TCCD may aid
to accurately diagnose a CRVO: it usually reveals a low velocity, or even a reverberant flow at central retinal vein.
Moreover, central retinal artery may also show a decreased
blood velocity. However, our patient presented with normal central retinal artery flow velocity, which may be explained by blood bypassing the occluded central retinal
vein through collateral venous channels—these are usually
small in caliber, beyond the resolution of colour Doppler.
The present clinical case underlines a potential new
neurosonologic application, as a diagnostic tool in CRVO,
particularly useful when ocular fundus cannot be properly
visualized.
Abbreviations
CRVO: Central retinal vein occlusion; TCCD: Transorbital colour
coded Doppler (TCCD)
Competing interests
The authors declare no conflict of interest.
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International Journal of Clinical Neurosciences and Mental Health 2016; 3(Suppl. 1):S14