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TJPRC: Journal of Ophthalmic Surgery and Ocular Pharmacology (TJPRC: JOSOP) Vol. 1, Issue 1, Dec 2016, 1-14 © TJPRC Pvt. Ltd.
ROLE OF ULTRASOUND IN EVALUATING OCULAR AND ORBITAL DISEASES
ZAIN IRFAN KHATIB 1 & SEETHALAKSHMI D K 2
1 M. S. Ophthalmology, Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India
2 Assistant Professor, Department of Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India
ABSTRACT
Purpose
The aim of the present study is to establish the role of B-scan Ultrasonography in: assessing the posterior
segment of eye in presence of opaque media and evaluating specific posterior segment ocular abnormalities even in the
presence of clear media, as and when indicated. For orbital leiosns, in evaluating the orbital tissue to assist in the
diagnosis of proptosis and assessing orbital tumour location, configuration, extent and relationship to adjacent structures.
Materials and Methods
A prospective cross sectional study was conducted between January 2014 to November 2015 on 71 eyes of 62
patients presenting to outpatient department of KIMS, Hubli. B-scan Ultrasound (with A-scan overlay) was performed
with a 12 Mhz probe.
Results
The overall sensitivity, specificity and accuracy of ultrasonography for diagnosing ocular lesions was 93.1%,
97.14% and 94.62% (P value < 0.0001) compared to 50.0%, 97.14% and 67.74% for clinical examination respectively.
The sensitivity, specificity and accuracy of ultrasonography for diagnosing orbital lesions was 82.60%, 97.14% and
93.55% (P value < 0.0001) respectively
Interpretation and Conclusions
B- scan ultrasonography was the initial imaging modality opted in most of the cases as it was readily available,
simple, cost effective, non ionizing, non invasive and reliable modality. It has a higher spatial and temporal resolution
compared to both CT and MRI for the diagnosis of ocular pathologies. It superseded the accuracy of ophthalmoscopy in
the diagnosis of posterior segment ocular pathologies with significant difference (p-value < 0.0001). However in certain
orbital pathologies; for the evaluation of bony involvement, extension to adjacent structures and intracranial extensions,
further evaluation with higher cross sectional imaging modalities (CT, MRI, Histopathology) were indicated. Sonological
diagnosis correlated very well with the final diagnosis and formed a major basis for management decisions in significant
number of cases.
KEYWORDS: Ultrasonography, B- Scan, Echo, Ocular, Orbital, CT, MRI, Histopathology
Received: Jul 22, 2016; Accepted: Aug 18, 2016; Published: Aug 30, 2016; Paper Id.: TJPRC:JOSOPDEC20161
INTRODUCTION
B - scan (brightness scan) is a real time 2 dimensional ultrasonography of the eye and orbit and is non
hazardous, atraumatic and invaluable in the evaluation of orbito-ocular lesions, especially in the presence of opaque
media when there is a suspicion of an intraocular mass.[1]
Original A
rticle
2 Zain Irfan Khatib & Seethalakshmi D K
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A-scan (amplitude scan) is a one-dimensional ultrasound and when combined with b-scan, it provides quantitative
data on the b-scan echoes (B-scan ultrasound with A-scan overlay).
Vitreoretinal diseases are the most common indication for ultrasonographic imaging of the posterior segment.
Although most conditions of the posterior segment can be viewed directly, in situations where there is media opacity
(e.g., because of vitreous haemorrhage), echography allows for evaluation of the vitreous, retina and choroid that otherwise
would be impossible. Using ultrasound, it is possible to identify, evaluate, and follow numerous posterior segment
conditions.[2]
Because of its ability to evaluate eyes using either clear or opaque media, ultrasonography has been a critical
adjunct in ophthalmology for more than 50 years in case of ocular inflammatory disorders.[3] Ultrasound is the best method
for the exploration of the eyeball. Pre-extraocular lens work up, intraocular foreign body localization, evaluation of
vitreoretinal disorders, and diagnosis and follow up of ocular tumours, are best achieved by ultrasound.
Ultrasound is also of great help in the assessment of the orbit, outside the globe.[4] MRI and CT of the retro
orbital structures have several advantages over ultrasound, including high resolution images with thin sections,
magnification techniques, and the capability for image reconstruction in multiple planes. These modalities demonstrate
lesions in the posterior and apical part of the orbit, and adjacent sinuses and intracranial structures. For these reasons, MRI
and CT are now the imaging modalities of choice in investigating orbital diseases. Their disadvantages include, the
delivery of radiation dose to the eye with CT; subtle lesions of the optic nerve are missed; and the examination may be
time consuming. Ultrasound has the advantage of rapidity and accessibility and, with its ability to identify the orbital walls,
optic nerve, extra ocular muscles and orbital masses, it is a useful first line investigation in proptosis.[5]
OBJECTIVES OF THE STUDY
• The aim of the present study is to establish the role of B-scan Ultrasonography in:
• Assessing the posterior segment of eye in presence of opaque media.
• Evaluating specific posterior segment ocular abnormalities even in the presence of clear media, as and when
indicated.
• Evaluating the orbital tissue to assist in the diagnosis of proptosis.
• Assessing orbital tumour location, configuration, extent and relationship to adjacent structures.
MATERIALS AND METHODS
Source of Data
Data was collected from all patients presenting with proptosis, symptoms suggestive of orbital lesions, and
posterior segment ocular lesions to the ophthalmology OPD, Karnataka Institute of Medical Sciences, Hubli between
January 2014 and November 2015.
Method of Collection of Data
A prospective correlational study was conducted over a period of two years (January 2014 to Novemeber 2015) on
71 eyes of 62 patients with symptoms related to eye and orbit. The patients were evaluated with high resolution
Ultrasonography using a 12 MHz probe. The ultrasonographic diagnoses were correlated with the clinical and laboratory
Role of Ultrasound in Evaluating Ocular and Orbital Diseases 3
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findings. Correlation with advanced imaging modalities (CT / MRI) and surgery with histopathology were done as
necessary.
Inclusion Criteria
• Patients clinically suspected to have orbital lesions, and all patients presenting with proptosis
• Patients presenting with opaque media, to rule out posterior segment ocular abnormalities.
• Patients presenting with clear media, in whom ultrasound was indicated.
Exclusion Criteria: Patients with open globe injuries were excluded from the study.
Technique of Sonographic Study
With the patient in supine position, Ultrasound was performed with closed eyelid after application of coupling gel
utilizing contact method. Linear high frequency probe (12MHz) of Appasamy Associates ultrasound system was used for
the study.
Longitudinal, transverse and axial scans were performed, both in static and with dynamic movements of eye after
instructing the patients.
Ultrasonographic diagnosis was made based on various acoustic characteristics studied in conjunction with
clinical data. Higher imaging modalities (CT/ MRI) were employed where necessary and findings were correlated with
ultrasonographic diagnosis. Surgery with histopathological correlation was done as applicable. Final diagnosis were made
based on these findings and compared with the ultrasonographic diagnosis.
RESULTS
We included a total of 62 patients in our study group (Table 1: Distribution).
Table 1: Distribution of Patients
No of Patients No of Eyes Ocular pathologies 42 48 Orbital pathologies 20 23
Total 62 71
Table 2: Distribution of Ocular Pathologies
Pathologies Number of Cases Rhegmatogenous Retinal Detachment 15 Proliferative Vitreoretinopathy 8 Vitreous Haemorrhage 7 Tractional Retinal Detachment 4 Posterior Vitreous Detachment 3 Lens dislocated in vitreous 3 Choroidal Detachment 2 Intraocular Foreign body (Posterior segment) 2 Posterior staphyloma 2 Endophthalmitis 2 Exudative Retinal Detachment 1 Globe size abnormality - Nanophthalmos 1 Asteroid Hyalosis 1 Choroidal melanoma 1
4 Zain Irfan Khatib & Seethalakshmi D K
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Table 3: Distribution of Orbital Pathologies
Pathologies No of Patients No of Eyes Thyroid Orbitopathy 3 6 Orbital Lymphoma 2 2 Cavernous Hemangioma 2 2 Dermoid Cyst 2 2 Maxillary sinus carcinoma 1 1 Schwannoma 1 1 Optic nerve meningioma 1 1 Ethmoidal sinus mucocoele 1 1 Langerhan cell Histiocytosis 1 1 Microphthalmos with orbital cyst 1 1 Orbital Myocysticercosis 1 1 Orbital Pseudotumour 1 1 Epidermal nevus syndrome 1 1 Subperiosteal abscess 1 1 Retrobulbar optic nerve thickening and calcification 1 1
Out of all the ocular pathologies in our study group (Table 2), the maximum detected were Rhegmatogenous
retinal detachments (29%) followed by Proliferative vitreoretinopathy (15%) and Vitreous haemorrhage (13%).
All orbital pathologies in our study (Table 3) were unilateral, except for 3 patients with Thyroid eye disease, all of
which were bilateral (6 eyes). In all the orbital cases, a detailed orbital B-scan ultrasound with A-scan overlay was
performed with the transverse, longitudinal and axial probe positions depending on the site of the suspected lesion.
ultrasound findings were correlated with clinical history, examination, and other investigation modalities like CT, MRI and
histopathology to come to a final diagnosis.
Among patients with ocular pathologies, the maximum percentage of patients were in the 26 - 40 years and 41 -
60 years age groups (30% each). There was a gender inequality with 27 males as compared to 15 females. Among the
individual pathologies, patients with VH were maximum in the 41 to 60 years age group and with a 85% male
predominance. In comparision, RRD and PVR patients were predominantly seen in the 26 to 40 years age group and with
an almost equal gender distribution. Most TRD patients were also seen in the 41 to 60 years age group with a male
predominance similar to VH. This was due to the fact that most of the patients with VH also had TRD and versa due to a
common entity being Diabetic retinopathy and its related complications which included both VH and TRD. IOFB was seen
in 2 cases, both being in middle aged males due to occupation related risks.
Most of the patients with orbital pathologies were in the 11 to 25 years age group (30%) followed by >60 years
age group (25%). There was almost equal gender distribution with 11 patients being males (55%) and 9 females (45%).
Out of the 20 patients, 17 had unilateral pathologies, with 5 being right sided, and 12 being left sided. Bilateral orbits were
involved in 3 patients.
For orbital lesions, Purnell first described ultrasound B scan patterns that have been reclassified into four general
diagnostic patterns:
• ACOUSTICALLY “CYSTIC” TUMOURS:
• Rounded regular outline
• Good acoustic transmission
Role of Ultrasound in Evaluating Ocular and Orbital Diseases 5
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• Sharp definition
• Good demarcation
• Rounded anterior border
• Posterior extent of tumour and outline well demonstrated
• ACOUSTICALLY “SOLID” TUMOURS:
• Rounded regular outline
• Poor acoustic transmission / high acoustic absorption
• Multiple internal echoes (echogenic interfaces)
• Sharply defined anterior border
• Relatively well demarcated
• Acoustic homogeneity
• ACOUSTICALLY “ANGIOMATOUS” TUMOURS:
• Irregular outline
• Good sound transmission
• Non encapsulated
• Diffuse with numerous finger like projections into retrobulbar fat pattern
• Acoustically well demarcated
• Definite acoustic hollowness
• Posterior extent well outlined
• Pulsatile flow on Doppler interrogation
• ACOUSTICALLY “INFILTRATIVE” TUMOURS:
• Highly irregular outline
• Very poor sound transmission
• Non encapsulated
• Poorly demarcated
• Scalloped / lobulated outline
• Acoustic solidity and homogeneity
• Posterior extent not delineable
• Localized flow in these lesions in all areas of orbit
6 Zain Irfan Khatib & Seethalakshmi D K
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Table 4: Acoustic Classification of Orbital Masses
Pathologies Acoustically
Cystic Acoustically
Solid Acoustically Angiomatous
Acoustically Infiltrative
Atypical Pattern
Orbital Lymphoma
⃝ Cavernous Hemangioma ⃝ Dermoid Cyst
⃝
Maxillary sinus carcinoma
⃝ Schwannoma
⃝
Optic nerve meningioma
⃝ Ethmoidal sinus mucocoele ⃝ Langerhan cell Histiocytosis ⃝ Microphthalmos with orbital cyst ⃝ Orbital Myocysticercosis
⃝
Subperiosteal abscess ⃝ We divided the orbital masses were divided into four categories based on the various acoustic charecteristics as
described earlier (Table 4).
In our study, the masses which predominantly followed the acoustically cystic pattern were Cavernous
hemangioma, Ethmoidal sinus mucocoele, Langerhan cell histiocytosis, Microphthalmos with orbital cyst, and
subperiosteal abscess.
Acoustically solid masses were Maxillary sinus carcinoma and Schwannoma.
Acoustically infiltrative masses were orbital lymphoma and Optic nerve meningioma.
There were no masses fitting the angiomatous group in our study. 2 masses which did not fit any of these 4
patterns were Dermoid cyst and orbital myocysticercosis. Dermoid cyst showed well defined anterior and posterior
borders, but unlike other cystic lesions, had very high internal echoes due to its tissue heterogeneity. Myocysticercosis of
the inferior rectus muscle showed a large cyst like enlargement of the muscle with well defined borders, but in the internal
structure its showed a central high reflective echo due to the scolex. Hence these 2 lesions were grouped separately as an
atypical pattern.
Table 5: Ocular Pathologies: Ophthalmoscopic Vs Ultrasound Diagnosis
No of
Patients Ophthalmoscopic
diagnosis Diagnosis missed on
Ophthalmoscopy Ultrsonographic
Diagnosis Diagnosis
Missed on USG RRD 15 9 6 15 0 TRD 4 2 2 4 0 ERD 1 0 1 1 0 CD 2 1 1 2 0 PVD 3 0 3 3 0 PVR 8 5 3 8 0 Post Staph 2 0 2 2 0 IOFB 2 0 2 2 0 Lens in vitreous 3 3 0 3 0 Endoph 2 0 2 2 0 Asteroid 1 1 0 1 0 Nanoph 2 0 2 2 0 VH 7 2 5 7 0 Ch Mel 1 1 0 1 0 Retinal Breaks 5 5 0 1 4
Total 58 29 29 54 4
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Out of the 58 pathologies studied, almost all of them were diagnosed on ultrasound (54 out of 58). Only four cases
of retinal tears were missed on ultrasound that were diagnosed clinically (Table 5). Thus, the sensitivity of ultrasound to
diagnose posterior segment ocular pathologies was 93.1% as compared to 50% sensitivity of ophthalmoscopic diagnosis.
Table 6: Orbital Pathologies: Ultrasound Vs Other Investigation Modalities
Pathologies Number of
Cases
Lesions Picked up by
USG
Lesions Missed on
USG
Diagnosis Made with Other Relevant
Investigations (CT, MRI, Histopath)
Thyroid Orbitopathy 6 4 2 6 Orbital Lymphoma 2 2 0 2 Cavernous Hemangioma 2 2 0 2 Dermoid Cyst 2 2 0 0 Maxillary sinus carcinoma 1 1 0 1 Schwannoma 1 1 0 1 Optic nerve meningioma 1 1 0 1 Ethmoidal sinus mucocoele 1 1 0 1 Langerhan cell Histiocytosis 1 1 0 1 Microphthalmos with orbital cyst 1 1 0 1 Orbital Myocysticercosis 1 1 0 0 Orbital Pseudotumour 1 0 1 1 Epidermal nevus syndrome 1 0 1 1 Subperiosteal abscess 1 1 0 1 Retrobulbar optic nerve thickening and calcification
1 1 0 1
Total 23 19 4 23
Out of the 23 orbital pathologies studied, 19 of them could be picked up on B-scan ultrasound with A-scan
overlay (Table 6). The other 4 lesions that were not picked up on ultrasound included 2 eyes of thyroid related proptosis, 1
case of orbital pseudotumour, and 1 case of eyelid nevus (as part of epidermal nevus syndrome). These lesions were
diagnosed with other investigations like CT, MRI and histopathology. Out of the 19 cases that were detected on ultrasound,
3 of them were diagnosed based on the ultrasound and clinical findings without needing any other investigations. These
included 2 cases of dermoid cyst, and 1 case of orbital myocysticercosis. For the remaining 16 cases, ultrasound findings
were correlated with CT, MRI and/or histopathology findings to make a final diagnosis. Based on these findings, the
sensitivity of ultrasound to pick up orbital lesions was 82.6%.
Table 7: Ultrasound Diagnosis for Ocular Vs Orbital Pathologies
Parameter Ultrasound Diagnosis
Ocular Orbital SENSITIVITY 93.1% 82.6% SPECIFICITY 97.14% 97.14% PPV 98.18% 90.47% NPV 89.47% 94.44% ACCURACY 94.62% 93.54% p - VALUE < 0.0001 < 0.0001
Statistical Methods: Descriptive statistical analysis has been carried out in the present study. Results on
continuous measurements are presented on Mean+/- SD (Min-Max) and results on categorical measurements are presented
in Number (%). Significance is assessed at 5% level of significance. Fisher Exact test has been used to find the significance
of association of Sonological diagnosis with final diagnosis. Diagnostic statistics such as sensitivity, Specificity, PPV, NPV
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and Accuracy has been used to find the correlation of CT scan with final diagnosis. Overall ultrasonography has a
reasonably high sensitivity and specificity with a high diagnostic accuracy in the diagnosis of both ocular and orbital
lesions (Table 7)
DISCUSSIONS
In our study, we evaluated a total 72 eyes of 61 patients with ocular and orbital diseases over a period of two
years. Out of these, 48 eyes of 42 patients had ocular pathologies, while 23 eyes of 20 patients had orbital pathologies.
Our study group included a wide range of patients with ocular and orbital pathologies with age ranging between 1
month and 70 years, with most of the patients being in the 5th and 6th decade. There was a gender slight inequality in our
study with a male to female ratio of 1.45:1. Out of 62 patients, 9 had bilateral involvement, 22 had right side and 31 had
left side involvement.
The most common indication for sonographic examination was 'presence of opaque media' (37%), followed by
'for evaluation of posterior segment pathology in presence of clear media' (32%). 'Proptosis' was the third most common
indication for ultrasound evaluation (27%), while ‘mass in orbit’ constituted just 4% of the indications for ultrasound
evaluation.
Out of the 48 eyes with ocular pathologies that we studied, there were a total of 58 posterior segment lesions that
were evaluated using clinical methods and ultrasound. Out of these, only 29 lesions were correctly diagnosed clinically
with ophthalmoscopic examination, while the other 29 lesions were missed. In contrast, ultrasound was able to correctly
diagnose 54 out of the 58 lesions, with 4 retinal tears being missed on ultrasound that were diagnosed on ophthalmoscopy.
The overall sensitivity, specificity, PPV, NPV and accuracy of ultrasound for the diagnosis of ocular
pathologies were 93.1 %, 97.14 %, 98.18 %, 89.47 % and 94.62 % (p- value < 0.0001) respectively compared to 50.0 %,
97.14 %, 96.67 %, 53.97 % and 67.74 % for ophthalmoscopic examination.
There were a total of 20 patients with orbital diseases that were included in the study group. Most of the lesions
were unilateral, except for three cases of thyroid orbitopathy which included both eyes, so a total of 23 eyes from the 20
patients were evaluated.
Most of the lesions that lesions could be picked up on B-scan ultrasound because most orbital masses are less
heterogenous than surrounding orbital tissue, thus having smaller echoes as compared to orbital tissue. Based on their
acoustic characteristics they were classified as acoustically cystic, solid, angiomatous or infiltrative.
Also, in our study we found that ultrasound B-scan was very effective in picking up early subtle thickening of
extraocular muscles in cases of Thyroid eye disease, which could be missed on CT scan and MRI. By using the
measurement guide, the exact thickness of the muscle belly could be measured on transverse and longitudinal scans, and
correlated with the normal values.
Out of the 23 lesions that were evaluated, 17 of them were picked up on ultrasound evaluation, and diagnosis
was made after correlating with other investigations like CT scan MRI and histopathology (FNAC, incision or excision
biopsy).
Three lesions (1 case of orbital myocysticercosis and 2 cases of dermoid cyst), were directly diagnosed based on
ultrasound findings without needing any further investigations.
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Four lesions (1 case of orbital pseudotumour, 1 case of eyelid nevus, and 1 case of thyroid eye disease with
bilateral involvement) were missed on ultrasound evaluation but subsequently diagnosed with the other investigation
modalities mentioned above.
The overall sensitivity, specificity, PPV, NPV and accuracy of ultrasound for the diagnosis of orbital
pathologies were 82.60 %, 97.14 %, 90.47%, 94.44 % and 93.55 % respectively with a p- value < 0.0001.
OCULAR PATHOLOGIES
Retinal Detachment: In our study, we had a total of 28 cases of retinal detachments, out of which there were 15
cases of pure RRD, 8 cases of RRD with PVR, 4 cases of TRD, and 1 case of ERD. Ultrasound was 100% sensitive in
diagnosing all types of retinal detachments, and was the most common imaging modality to pick up retinal detachment in
presence of opaque media. Even in the presence of clear media, it was useful to confirm the diagnosis and differentiate
between the different types of retinal detachments.
• Pure RRD: These cases typically were attached to the optic nerve head, and had a concave configuration, unless
it was a bullous RD. There were 3 cases of bullous RD associated with giant retinal tears where the configuration
of RD was convex and mobile on kinetic echography (Figure 1).
• RRD with PVR: These cases of RD typically were fixed with no movement and showed a classical funnel shaped
appearance (open or closed funnel), sometimes associated with intraretinal cysts (Figure 4).
• TRD: These cases were associated mostly with VH, and showed a typical “tented up” appearance and showed
PVD attached to multiple points on the retina causing traction
• ERD: The single case of ERD in our study was a case of Sturge Weber syndrome having a typical convex RD,
with shifting fluid along with choroidoscleral thickening suggestive of ERD.
Vitreous Haemorrhage: We had 7 cases of VH in our study, and all were diagnosed with ultrasound, adjusting
the gain as per need. It showed multiple high reflective echoes in vitreous cavity mostly in posterior inferior part of
vitreous, and commonly associated with TRD.
Posterior Vitreous Detachment: All 3 cases of PVD in our study were diagnosed on ultrasound. PVD showed a
low to medium reflective membranous echoes in the vitreous cavity with freely undulating after movements on kinetic
echography.
Choroidal Detachment: We had 2 cases of choroidal detachment, 1 case was due to post op hypotony and other
due to uveal effusion associated with Sturge Weber syndrome. CD showed a high reflective membranous echo with convex
configuration and which does not extend posteriorly beyond vortex vein attachment.
Intraocular Foreign Body: 2 cases of IOFB, both seen in young males in 3rd decade were easily picked up on
ultrasound. Both cases were diagnosed clinically but diagnosis was confirmed by ultrasound which showed a characteristic
very high reflective echo with posterior orbital shadowing.
Endophthalmitis: We has 2 cases, both showed the same findings of multiple low to moderate reflective echoes
filling the entire vitreous cavity along with choroido-scleral thickening.
Lens in Vitreous: In our study, we had 3 cases of blunt trauma associated with complete displacement of lens the
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vitreous cavity. On ultrasound it appeared as a large IOFB with two high spikes on A-scan corresponding to the anterior
and posterior lens capsule.
Posterior Staphyloma: Both cases of posterior staphyloma in our study were missed on clinical examination but
diagnosed on ultrasound as a dome shaped excavation in the posterior coats of the eye, with an increased axial length.
Asteroid Hyalosis: We had a single case of Asteroid Hyalosis in a diabetic patient, which typically showed the
vitreous cavity filled with multiple highly reflective echoes, with a clear thin zone between the lesion and the retina.
Choroidal melanoma: We had 1 case of choroidal melanoma of a lady presenting in the 5th decade, with a
subclinical lesion in the periphery showing the typical ‘collar stud’ appearance with internal homogeneity.
Nanophthalmos: This patient was a middle aged man having high hypermetropia with one eye significant optic
disc cupping and the other eye having pseudopapillitis on ophthalmoscopic examination. On performing ultrasound, there
was reduced axial length of both eyes (18mm), thus making a diagnosis of bilateral nanophthalmos with high
hypermetropia and unilateral glaucoma.
Orbital Pathologies
Thyroid Orbitopathy: In our study, we had 3 cases of thyroid orbitopathy, all 3 cases having bilateral proptosis,
so a total of 6 eyes were studied. In 2 patients, B-scan ultrasound was able to pick up extraocular muscle thickening which
correlated with the CT scan findings. In the other case, we were not able to pick up the cause of proptosis on ultrasound,
but CT scan showed generalized thickening of orbital soft tissue.
Orbital Lymphoma: We had to patients diagnosed to have orbital Lymphoma, both were elderly males
presenting with a gradual onset painless proptosis. In one case, ultrasound findings showed the presence of a large mass of
low reflective echoes whose posterior extent could not be visualized, and compressing the globe from all sides. The other
case on ultrasound showed a large mass in the infero-medial orbit with well defined anterior border and posterior extent
visualized, with internal structure showing heterogenous medium reflective echoes (Figure 2B). CT scan and
histopathology for both cases later confirmed the diagnosis as Lymphoma.
Dermoid Cyst: 2 cases of dermoid cyst were diagnosed in our study, both were females in their 2nd decade
presenting with a mass in their superolateral orbits. A para-ocular scan was done for both cases directly over the lesion.
They showed a characteristic pattern on ultrasound, having well defined anterior and posterior borders and high internal
echoes due to the heterogeneous internal structure. The diagnosis was made based on ultrasound findings, and no
additional investigation was needed.
Cavernous Hemangioma: There were 2 cases diagnosed, one patient being in the 2nd decade while other was an
older patient in 7th decade. Both patients presented with an axial proptosis, slow growing and painless. On ultrasound, both
showed an intraconal mass with sharp anterior border, medium reflective internal echoes, and ill defined posterior border
due to tissue shadowing effect. CT, MRI and histopathology confirmed the final diagnosis.
Orbital Myocysticercosis: A young female patient presented with sudden onset proptosis with pain since 15
days. Ultrasound showed a large well defined mass in the inferior quadrant with well defined anterior and posterior
borders, and a large central echo probably suggestive of a scolex (Figure 3). A course of Albendazole and oral steroids was
given for 1 month, and the lesion completely resolved.
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Microphthalmos with Orbital Cyst: A 9 year old female presented with loss of vision since birth along with
proptosis in right eye. On examination, features suggestive of microphthalmos were present, and on ultrasound, a large
echolucent cavity with well defined borders in the inferomedial quadrant was seen. There was also reduced axial length of
18mm, which confirmed the diagnosis of microphthalmos with orbital cyst.
Ethmoidal Sinus Mucocoele: A 54 year old male presented with left eye proptosis of 10 days without visual loss.
On ultrasound, an illdefined hypoechoic lesion was seen in the medial orbital cavity extending into the retrobulbar space,
posterior extent could not be made out. CT scan of paranasal sinuses confirmed the diagnosis and an endonasal ethmoidal
exploration was planned.
Maxillary Sinus Carcinoma: A 12 year old boy presented with proptosis in left eye since 2 months associated
with pain and recent onset decrease of vision. A large hypoechoic lesion about 16mm in thickness, anterior border well
defined, posterior border ill defined, involving medial, inferior and retro-orbital spaces, obliterating the optic nerve shadow
(Figure 2A). CT scan and endonasal biopsy confirmed it to be a carcinoma arising from the maxillary sinus.
Optic Nerve Sheath Glioma: A 62 year old male presented with 6 months history of right eye proptosis with pain
and decreased vision since 1 month. Fundus showed optociliary shunt vessels and optic atrophyin the involved eye.
Ultrasound showed an ill defined, moderate echogenic lesion in the intraconal space obliterating the optic nerve shadow.
CT scan and MRI confirmed the diagnosis to be optic nerve sheath meningioma, and an excisional biopsy was planned.
Langerhan Cell Histiocytosis (Eosinophilic Granuloma): A 3 year old female child presented wit left eye
gradual proptosis since 1 year. Ultrasound showed a well defined echolucent mass in the superotemporal orbit with sharp
borders. A differential diagnosis was given based on these findings. Complete blood counts showing eosinophilia and
FNAC confirmed the diagnosis and surgical excision was planned.
Schwannoma: A 45 year old male presented with 2 years history of left eye gradual painless proptosis with no
visual loss, fundus showing optic disc edema. On ultrasound, a large hypoechoic mass was seen in retrobulbar and superior
orbital cavity, measuring horizontally 16 mm, while vertical extent could not be estimated superiorly. Lesions was having
slight irregular internal pattern, and optic nerve shadow was obliterated. CT scan and histopathology confirmed it to be a
schwannoma arising from one of the branches of ophthalmic nerve in the superior orbit.
Epidermal Nevus Syndrome (Nevus of Eyelid): A four year old female presented with a painless mass in the
upper eyelid since birth. On examination, the mass was pigmented, illdefined, and causing mechanical ptosis. An
ultrasound direct para-ocualar scan was performed, but did not reveal any significant findings. A histopathologocal FNAC
revealed it to be a benign eyelid nevus as part of epidermal nevus syndrome.
Reterobulbar Optic Nerve Thickening: A 30 year old female presented with 2 years sudden onset decrease of
vision in left eye. Fundus showed a pale optic disc. Bscan ultrasound showed a thickened optic nerve shadow with some
irregular echoes as compared to the right eye. CT scan confirmed the diagnosis showing a thickened and calcified
retrobulbar optic nerve probably due to old inflammation.
Orbital pseudotumour (Idiopathic orbital inflammato ry disease): A 40 year old male presented with 6 months
history of proptosis associated with pain since 3 months. Ultrasound examination did not reveal any significant findings.
CT scan showed an irregular illdefined lesion in the retro-orbital cavity. A course of oral steroids was given for 1 month
and the patients symptoms resolved, thus making the most likely diagnosis as pseudotumour of orbit.
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CONCLUSIONS
Most of the ocular pathologies our study group were in the 4th and 5th decade and there was a gender inequality
with a male to female ratio of 1.8:1. The right and left eyes were almost equally affected (45% and 41% respectively) with
14% bilateral involvement.
Most of orbital pathologies were seen in the 11 to 25 year age group (30%), with a near uniform gender
predilection (M:F: 1:1.2). There was a predilection for involvement of left eye (60%) as compared to right eye (25%) and
15% showed bilateral involvement.
The most common indication for ultrasound evaluation was ‘opaque media’ (37%), followed by ‘posterior
segment evaluation in clear media’ (32%), followed by ‘proptosis’ (27%), and lastly, ‘mass in orbit’ (4%). The most
common ocular pathology in our study was rhegmatogenous retinal detachment, followed by proliferative
vitreoretinopathy. The most common orbital pathology was thyroid orbitopathy, followed by cavernous hemangioma.
orbital lymphoma and dermoid cyst.
The overall sensitivity, specificity, PPV, NPV and accuracy of ultrasound for the diagnosis of ocular
pathologies were 93.1 %, 97.14 %, 98.18 %, 89.47 % and 94.62 % (p- value < 0.0001) respectively compared to 50.0 %,
97.14 %, 96.67 %, 53.97 % and 67.74 % for ophthalmoscopic examination.
The overall sensitivity, specificity, PPV, NPV and accuracy of ultrasound for the diagnosis of extraocular
pathologies were 82.60 %, 97.14 %, 90.47%, 94.44 % and 93.55 % respectively with a p- value < 0.0001.
Ultrasonography is readily available, simple, cost effective, non ionizing, non invasive and a reliable imaging
modality for posterior segment ocular pathologies . It readily establishes the diagnosis in significant number of cases. It has
a higher spatial and temporal resolution compared to both CT and MRI for the diagnosis of ocular pathologies. It
superseded the accuracy of ophthalmoscopic diagnosis with significant difference (p- value < 0.0001).
Even though for most orbital pathologies, it needs additional investigations (CT, MRI, histopathology) for
confirming the diagnosis, ultrasound proves a useful imaging tool and correlates very well with the final diagnosis.
REFERENCES
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Role of Ultrasound in Evaluating Ocular and Orbital Diseases 13
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APPENDICES
Legends for Images
FIGURE 1- A, B, C: Bullous rhegmatogenous retinal detachment due to giant retinal tears
Figure 1- A, B, C: Bullous Rhegmatogenous Retinal Detachment Due to Giant Retinal Tears
Figure 2 A: Lymphoma: Ill-Defined Borders and Irregular Pattern (Acoustically Infiltrative Tumour), B: Maxillary Sinus Tumour: Well Defined Anterior Border, with ill-Defined Posterior
Border Due to Significant Tissue Shadowning (Acoustically Solid Tumour)
14 Zain Irfan Khatib & Seethalakshmi D K
www.tjprc.org [email protected]
Figure 3: Cysticercosis of Inferior Rectus Muscle A- Ultrasound Shows a Cyst Like well Defined Echolucent Lesion in Extraconal Space B- A high Reflective Echo in the Center of the Lesion can be seen,
Suggestive of a Scolex C: MRI Shows Thickening of the Inferior Rectus Muscle
Figure 4 A, B: Proliferative Vitreoretinopathy: A- Retinal Detachment with Multiple Intraretinal Cysts, B- Closed Funnel Retinal Detachment