Differential Diagnosis for Blurr or Dark Blobs after Retinal Photocoagulation

Single Most Likely Diagnosis

• Postoperative Vitreous Hemorrhage: This is a common complication following retinal photocoagulation, especially if the treatment was extensive or if the patient has underlying conditions like diabetic retinopathy. The hemorrhage can cause sudden vision loss, blurriness, or the perception of dark blobs due to blood obstructing the visual pathway.

Other Likely Diagnoses

• Cystoid Macular Edema (CME): This condition can occur after retinal photocoagulation as a result of inflammation and can cause blurred vision and metamorphopsia. CME is a known complication of many retinal treatments and surgeries.
• Retinal Detachment: Although less common, retinal detachment can occur as a complication of retinal photocoagulation, especially if the treatment inadvertently creates a retinal break. Symptoms can include sudden onset of floaters, flashes of light, and a curtain or shadow descending over the field of vision.
• Intraocular Inflammation (Uveitis): Postoperative inflammation can cause symptoms such as blurred vision, pain, redness, and sensitivity to light. While not as directly related to the symptom of dark blobs, significant inflammation can impair vision.

Do Not Miss Diagnoses

• Endophthalmitis: This is a severe, vision-threatening infection within the eye that can occur after any intraocular procedure, including retinal photocoagulation. Symptoms include severe eye pain, redness, decreased vision, and possibly a hypopyon (accumulation of pus in the anterior chamber). Although rare, endophthalmitis is an emergency that requires immediate treatment.
• Suprachoroidal Hemorrhage: A rare but potentially devastating complication that can occur during or after ocular surgery, including retinal photocoagulation. It presents with severe eye pain, decreased vision, and possibly a tense globe.

Rare Diagnoses

• Choroidal Neovascularization (CNV): While more commonly associated with age-related macular degeneration, CNV can theoretically occur as a rare complication of retinal photocoagulation, especially if the treatment inadvertently damages the retinal pigment epithelium or Bruch's membrane, leading to the growth of new, fragile blood vessels under the retina.
• Retinal Pigment Epithelial Tear: This can occur after retinal photocoagulation, especially in areas with pre-existing retinal pigment epithelium (RPE) pathology. Symptoms might include sudden changes in vision, but it's less directly associated with the symptom of dark blobs compared to other diagnoses.