Acute persistent visual loss
1. 📌 Definition
- Acute
persistent visual loss = สูญเสียการมองเห็น ≥ 24 ชั่วโมง
- Transient
visual loss (<24 hr) →
ถือเป็น TIA equivalent ต้องประเมินแบบ
stroke
2. 🚨 Clinical importance
- ภาวะฉุกเฉิน → ต้อง diagnose + treat อย่างรวดเร็ว
- delay → เสี่ยง permanent
blindness / stroke
3. 🧩 Approach (core
framework)
🔑 3 คำถามหลัก
1.
Monocular vs Binocular
2.
Painful vs painless
3.
Red eye vs white eye
4. 🔍 Localization (สำคัญที่สุด)
|
Level |
Clues |
|
Media (cornea/lens/vitreous) |
red eye / opacity / ↓ red reflex |
|
Retina |
painless, fundus abnormal |
|
Optic nerve |
RAPD + monocular |
|
Post-chiasm |
binocular / homonymous field
defect |
5. ⚠️ Red flags (ส่ง ER
/ consult ด่วน)
- sudden
painless severe loss →
CRAO
- painful
red eye + N/V → acute
angle-closure glaucoma
- floaters
+ curtain → retinal
detachment
- age
>50 + headache → GCA
- neuro
deficit → stroke
6. 🧠 Etiology (แบ่งเป็นระบบ)
🔴 A. Media causes
(anterior eye)
1. Cornea (abrasion / keratitis)
- pain,
red eye, tearing
- fluorescein
positive
- contact
lens → suspect
infection
2. Acute angle-closure glaucoma
- severe
pain, headache, N/V
- IOP
40–80 mmHg
- fixed
mid-dilated pupil
👉 emergency
3. Vitreous hemorrhage
- painless
floaters ± photopsia
- ↓ red reflex
4. Uveitis / Endophthalmitis
- inflammation
± infection
👉 ต้อง consult ophthalmology ภายใน 24 hr
🟡 B. Retinal causes
1. Central retinal artery occlusion (CRAO)
- sudden,
severe, painless vision loss
- cherry-red
spot
- = retinal
stroke
👉 stroke workup ทันที
2. Central retinal vein occlusion (CRVO)
- subacute
painless blurred vision
- fundus
= “blood and thunder”
3. Retinal detachment
- floaters
+ flashes → curtain
- painless
👉 consult <24 hr
4. Acute maculopathy
- central
scotoma / distortion
- ต้อง OCT (optical coherence tomography)
🔵 C. Optic nerve causes
1. Ischemic optic neuropathy
- sudden
painless loss
- altitudinal
defect
- RAPD
+
👉 ต้อง rule
out GCA
2. Optic neuritis
- young
patient
- pain
with eye movement
- ↓ color vision
- assoc.
multiple sclerosis
3. Papilledema
- bilateral
- ↑ ICP
- transient
obscuration + headache
🟣 D. Post-chiasmal causes
1. Stroke (most common)
- homonymous
hemianopia
- ±
neuro deficit
2. Pituitary apoplexy
- sudden
vision loss + severe headache
👉 emergency MRI
3. Cortical blindness
- bilateral
occipital lesion
- eye
exam normal
⚫ E. Others
- trauma
(globe rupture, hyphema)
- drug-induced
(topiramate →
glaucoma)
- functional
(diagnosis of exclusion)
7. 🩺 Physical exam (must do)
Basic
- visual
acuity (ทุก case)
- visual
field
- pupils
→ RAPD
Key findings
- RAPD → optic nerve lesion
- ↓ red reflex → media / vitreous / retina
- red
eye → anterior segment
8. 🧪 Investigation
Essential
- fundoscopy
- IOP
- fluorescein
stain
Advanced
- OCT → macula
- MRI
brain/orbit → optic
nerve / stroke
- POCOUS
→ retinal detachment
(ED setting)
9. ⚡ Practical ER Algorithm
Step 1: Pain?
- Painful
→ cornea / glaucoma /
optic neuritis
- Painless
→ retina / vascular /
neuro
Step 2: Red eye?
- Yes → anterior segment
- No → retina / optic nerve /
brain
Step 3: Monocular vs binocular
- Monocular
→ eye/optic nerve
- Binocular
→ brain
🔑 Take-home messages
- Acute
vision loss = emergency
- ต้อง localize ก่อน diagnose
- CRAO
= stroke equivalent
- GCA
ห้ามพลาด → steroid ทันที
- retinal
detachment / glaucoma →
urgent consult
- ตรวจ visual acuity + RAPD ทุกคน
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