DISEASES OF THE ORBIT Flashcards
IDIOPATHIC STENOSIS
the most common cause of NLDO
Wegener disease
granulomatosis with polyangiitis
sump syndrome
surgical opening in the lacrimal bone is too small and too high
the lower end of the nasolacrimal duct in the region of the valve of Hasner
this is the last portion of the lacrimal drainage system to canalize which is soon after birth
Leukocoria or cats eye reflex
this is seen in retinoblastoma and is the most common presentation
also known as white pupillary reflex
Probing
the definitive management for NLDO
dacryocystitis
infection of the lacrimal sac
epiphora
excessive tearing/watering of the eye
Flucloxacillin or co-amoxiclav
the treatment for acute dacryocystitis
mucocele
this is usually evident as a painless swelling at the inner canthus of the eye in patients with chronic dacryocystitis
Dacryocystorhinostomy
the treatment for chronic dacryocystitis
Retinoblastoma
the most common primary intraocular malignancy of childhood
Flexner Wintersteiner Rosettes
formation of these help in the differentiation of retinoblastoma
RB1
the tumor suppressor gene in which mutations predisposing to retinoblastoma occurs
germline mutations
these mutations are autosomal dominant
group A
small intraretinal tumors whose sizes are less than 3 mm and they are away from foveola and disc
group b
tumors are larger than 3 mm and they are macular to juxtapapillary location or with subretinal fluid
group c
tumor with focal subretinal or vitreous seeding within 3mm of the tumor
group D
tumor with diffuse subretinal or vitreous seeding more than 3 mm from the tumor
group e
extensive retinoblastoma occupying more than 50% of the globe with or without neovascular glaucoma, hemorrhage, an extension of the tumor to the optic nerve or anterior chamber
intraretinal tumor
a homogenous dome-shaped white lesion that can become irregular with white flecks of calcification
endophytic
into the vitreous space
exophytic
into the subretinal space
red reflex testing
simple screening test for leukocoria
chronic Toxocara endophthalmitis
may cause a cyclitic membrane and a white pupil
vitreoretinal dysplasia
caused by faulty differentiation of the retina and vitreous that results in a detached dysplastic retina forming a retrolental mass with leukocoria
Norrie disease
x linked where males are blind at birth or early infancy and there are mutations in the NDP gene that causes this
Incontinentia pigmenti
x linked that is lethal in utero for boys and there are mutations found in the NEMO gene for this
Walker warburg syndrome
autosomal recessive where there is an absence of cortical gyri
Retinoma or Retinocytoma
this is manifesting as a whitish dome-shaped lesion and can later become or transform into retinoblastoma
preseptal cellulitis
infection of the subcutaneous tissues anterior to the orbital septum
S aureus and S pyogenes
organisms usually responsible for preseptal cellulitis
bacterial orbital cellulitis
serious infection of the soft tissues behind the orbital septum which can be sight and life threatening
ethmoid sinus
this is typically the main originating cause of bacterial cellulitis
optic nerve compression
if there is a RAOD and color vision impairment and VA is reduced
SUBCUTANEOUS EMPHYSEMA
there is a crackling sensation on palpation due to air in the subcutaneous tissues
differential intraocular pressure test
increased IOP as a restricted muscle presses on the globe
