Tumors of the Eye and Orbit Flashcards
Tumors of the Eye and Orbit
What is the most common and next most common primary intraocular malignancy in adults?
most common is melanoma followed by lymphoma
Tumors of the Eye and Orbit
What is the most common and next most common tumor malignancy in children?
most common is retinoblastoma followed by medulloepithelioma
Tumors of the Eye and Orbit
What are the two most common primary tumors that metastasize to the intraocular areas?
breast
lung
Tumors of the Eye and Orbit
Radiation Tolerance
Loss of eyelashes may occur at doses as low as ___ using standard fractionation?
20 Gy
Tumors of the Eye and Orbit
Radiation Tolerance
Xerophthalima may occur at doses as low as ___ ?
24 to 26 Gy
Tumors of the Eye and Orbit
Radiation Tolerance
Acute conjunctivitis is common with doses ≥____
30 Gy
Tumors of the Eye and Orbit
Radiation Tolerance
Early dry eye syndrome (9 to 10 months) is usually caused by doses >____.
57 Gy
Tumors of the Eye and Orbit
Radiation Tolerance
Late dry eye syndrome (4 to 11 years) is usually caused by doses >____.
30 to 45 Gy
Moderate-dose orbital RT (30 to 45 Gy) can cause dry eye syndrome 4 to 11 years after treatment, whereas higher doses (>57 Gy) can produce it in 9 to 10 months.
Tumors of the Eye and Orbit
Radiation Tolerance
If possible, treating with the eyes closed reduces the risk of RT-induced conjuctivitis.
TRUE or FALSE?
False. *** Conjunctivitis can be reduced by treating with an open eye with megavoltage equipment if the clinical situation permits.
Tumors of the Eye and Orbit
Radiation Tolerance
I. For the cornea, what are the doses associated with
punctate epithelial erosions,
corneal edema, and
perforation, respectively?
II. These radiation doses are mainly responsible for most acute corneal toxicities.
TRUE or FALSE?
30 to 50
40 to 50
60 Gy
False.
***
Although RT can directly injure the cornea, most acute corneal toxicity results
from loss of the tear film with secondary keratitis sicca.
Tumors of the Eye and Orbit
Radiation Tolerance
The iris is relatively radioresistant, and thus, acute iritis is rare.
However,
persistent iritis, with symptoms such as pain, red eye, and blurred vision, has
been observed after hypofractionated RT doses of __ to __Gy and after doses
≥__ Gy given with conventional fractionation.
30 to 40 (hf)
70 (cf)
Tumors of the Eye and Orbit
Radiation Tolerance
I. The estimated risk of cataract for 1-Gy exposure to the lens during childhood is 50%.
II. In adults, after 2.5 to 6.5 Gy, there is a 33% of progressive cataract with latent period of 4 years, whereas after 6.51 to 11.5 Gy, there is a 66% risk with a latent period of 8 years.
Which is TRUE?
I.
***
Hall estimated 50% risk of cataract for 1-Gy exposure to the lens during childhood.
In adults, higher doses are associated with radiation-induced cataract:
After 2.5 to 6.5 Gy, there is a 33% of progressive cataract with latent period of 8 years, whereas after 6.51 to 11.5 Gy, there is a 66% risk with a latent period of 4 years.
Tumors of the Eye and Orbit
Radiation Tolerance
What is the he threshold dose for retinal damage?
30 to 35 Gy
Tumors of the Eye and Orbit
Radiation Tolerance
In a review by investigators from the Mayo
Clinic, the risk of RION was almost zero with conventionally fractionated doses
≤50 Gy and still rare with maximum dose <55 Gy.
Fraction size was of primary importance: In cases where >60 Gy was
received, fraction size was more important than total dose in producing RION.
TRUE or FALSE?
True.
***
The 15-year actuarial risk was 11% when fraction size was <1.9 Gy compared
with 47% when fraction size was >1.9 Gy.
Tumors of the Eye and Orbit
What are the RT fractionations used in the treatment of pterygium?
from benign disease chapter
3 Gy x 10 to 6 Gy x 10
30 Gy/3fractions (Nakamatsu et al.)
25 Gy × 1
low fractionation (2 Gy in 10 fractions) to high fractionation dose (5 Gy in 7 fractions) beta radiotherapy (Viena et al.)
Tumors of the Eye and Orbit
Choroidal hemangiomas are benign vascular tumors of the choroid, characterized as either circumscribed or
diffuse.
Which is usually diagnosed in young patients wither because of fundus examination prompted by a facial hemangiomaassociated with Sturg-Weber syndrome?
diffuse
Tumors of the Eye and Orbit
I. The clinical course of both form of choroidal
hemangioma is highly variable, with visual impairment ranging from none to total blindness.
II. Neither variety of choroidal hemangioma metastasizes or
transforms to malignancy.
Which is/are TRUE?
Both.
***
Therefore, the primary indication for treatment is to
prevent loss of visual acuity.
Tumors of the Eye and Orbit
What is the usual treatment for circumscribed lesions (eye chapter) and for CH that are not near the central visual structures such as macula and papilla (benign disease chapter)
photodynamic therapy (eye chapter)
```
PDT
and/or
Photocoagulation
and/or
transpupillary thermotherapy
benign diseases chapter
~~~
Tumors of the Eye and Orbit
Dose range for EBRT (photon) that can result in flattening of the hemangioma, resorption of subretinal fluid, and reattachment of the retina within 6 to 12 months.
18 to 30 in 10-18fx
In very advanced cases with retinal detachment, a higher dose of
36 Gy in fractions of 1.8 Gy appear to be efficacious
Tumors of the Eye and Orbit
Brachytherapy can be considered for CH particularly for circumscribed CH.
TRUE or FALSE?
True.
This treatment usually
achieves resolution of subretinal fluid and reattachment of the retina with
preservation of pretreatment visual acuity
Tumors of the Eye and Orbit
Brachytherapy dose for CH varies with isotope, but in a study using 125-I, what is the dose to the apex of the lesion that caused tumor regression in 100% of cases treated?
48 Gy
Tumors of the Eye and Orbit
At the Institut Curie series, what dose was used for CH that resulted in retinal reattachment occurred in all
cases, and a completely flat scar was obtained in 91.5%?
20 CGyE.
Tumors of the Eye and Orbit
(from benign disease chapter)
As reported by Schilling, what is the 3DCRT dose for circumscribed CH?
for diffuse CH?
Retinal reattachment occurred in 64% of the cases with improved vision in 50% and stable vision in 50%.
18 to 20 Gy for circumscribed CH
30 Gy for diffuse CH given in 1.8- to 2-Gy daily fractions.
Tumors of the Eye and Orbit
(from benign disease chapter)
Fractionated proton radiotherapy doses range from _________.
In the study by Zografos et al., all 54 cases experienced retinal reattachment and visual acuity was improved in 70%.
Levy-Gabriel et al. demonstrated a 100% rate of retinal reattachment and substantial improvement in visual acuity using proton beam therapy.
16.4 to 30 Gy in four fractions.
Tumors of the Eye and Orbit
Capillary hemangiomas are benign endothelial cell neoplasms that rarely occur on the eyelids or skin of the orbit.
I. Retinal capillary hemangiomas may represent component of the Beckwith-Wiedemman syndrome, and lesions of the face that occupy the distribution of the trigeminal nerve can be a component of Sturge-Weber syndrome.
II. The natural history of these lesions is usually spontaneous regression over 3 to 4 years, making conservative management the treatment of choice.
III. Lesions that are large enough to obstruct vision and amblyopia may occur.
Treatment options then include corticosteroids, interferon alfa-2a, laser therapy, embolization, immunomodulators, surgery, and systemic propranolol.
IV. RT has been historically used in the management of capillary hemangiomas with original studies showing that doses in the 16 to 20 Gy range provide effective local control.
Which is FALSE?
I. von Hippel-Lindau syndrome (VHL) - not Beckwith-Wiedemann
:P
oo na. pero…
ganyan magpatest board examiners.
Tumors of the Eye and Orbit
What are the characteristic imaging features in orbital pseudotumor?
extraocular muscle enlargement,
optic nerve thickening,
and inflammation of retrobulbar adipose tissue.
(additional from benign disease chapter: enhances with contrast)
Tumors of the Eye and Orbit
(from benign disease chapter)
Orbital pseudotumor presents as a chronic inflammation of the orbital soft tissues.
TRUE or FALSE?
False.
symptoms present acutely.
Tumors of the Eye and Orbit
RT dose for orbital pseudotumor as reported by Mathiesen.
(both from this chapter and benign disease chapter)
20 Gy/10 fx
additional info from benign disease chapter:
Prabhu et al. reported on 26 orbits affected with OP in 20 patients treated with radiation therapy (25.2 to 30.6 Gy) between 2002 and 2011.
The majority (85%) demonstrated a response to RT, and 70% of the patients initially on steroids were completely off steroids by the last follow-up visit.
Long-term complications occurred in seven patients, the majority of which were cataracts.
Tumors of the Eye and Orbit
RT dose. TO/GO
20 Gy/10fx
Tumors of the Eye and Orbit
Most common improvement in symptoms after RT for TO/GO
motility impairment (Mourits) (Prummel)
Tumors of the Eye and Orbit
(from benign disease chapter)
Graves ophthalmopathy (GO), also referred to as Graves orbitopathy or thyroid eye disease, is an autoimmune disorder affecting the musculature of the orbits. The presence of activated \_\_ lymphocytes leads to an inflammatory reaction secondary to the release of cytokines.
T
Tumors of the Eye and Orbit
(from benign disease chapter)
What are the parameters of SPECS, a scoring system for TO/GO.
Soft tissue involvement,
Proptosis,
Extraocular movements,
Corneal involvement, and
Sight (visual acuity)
Tumors of the Eye and Orbit
(from benign disease chapter)
What are the most commonly involved muscles in GO/TO?
inferior and medial rectus muscles.
Tumors of the Eye and Orbit
Metastases to the uvea is more common than primary ocular cancers.
Within the uvea, what is the most common site of metastasis?
choroid (88%)
followed by iris (9%) and ciliary body (2%).
(Shields and colleagues)