Study describes ‘triangle sign’ as key to differentiating total choroidal detachments and suprachoroidal hemorrhages

Researchers described that the “triangle sign” seen on ultrasound is a “distinctive and reliable” ultrasound feature for differentiating total choroidal detachments (CHs) and suprachoroidal hemorrhages (SCHs),¹ Vaidehi D Bhatt, MD, reported. Dr Bhatt, a specialist in ultrasound biomicroscopy (UBM), is from the UBM Institute, Mumbai, India, and was joined in the study by colleagues from the Department of Retina, Rajan Eye Care Pvt. Ltd., Chennai, India, and the University Eye Clinic Maastricht, Maastricht, the Netherlands.

The study’s authors defined the triangle sign as the “hypoechoic/anechoic triangular shape of the vitreous anterior to the optic disc in cases of total CD.”

Dr Bhatt and colleagues explained that CDs are characterised by choroidal separation from the sclera and encompass clinical scenarios that present with both serous and hemorrhagic manifestations.^2,3 Serous detachments result from fluid accumulation in the suprachoroidal space often resulting from hypotony, inflammation, or uveitis,^4-6 while hemorrhagic choroidal detachments occur because of bleeding into the same potential space, which is a more complex clinical picture that must be differentiated from other ocular conditions, they emphasised.^4-6

Two choroidal detachments, a serous choroidal detachment (A, red arrow) and suprachoroidal hemorrhage (B, red arrow), do not exhibit the triangle sign. Image credit: Bhatt VD, Bhatt DC, Bhatt KD, et al.¹

In an instance of total choroidal detachment, there is a hypoechoic/anechoic triangular shape of the vitreous anterior to the optic disc, highlighted here in blue. Image credit: Bhatt VD, Bhatt DC, Bhatt KD, et al.¹

The retrospective study under discussion investigated the diagnostic value of ultrasound B-scan and introduced the triangle sign as a novel indicator, which, they postulated, may be a potential tool to help clinicians differentiate between CDs and SCHs from retinal detachments (RDs) and vitreous hemorrhages (VHs).

B-scan results

The investigators studied consecutive cases of patients with total CD and SCH who were undergoing B-scans. They looked for the triangle sign in the two pathologies, then categorised the cases by subtype and etiology, and described the role of the triangle sign in differentiating the pathologies from RDs and VHs.

The study included 36 eyes with a total CD and SCH. Dr. Bhatt and colleagues reported that of the 31 cases with a total SCH, 58.1% were associated with an intraocular surgery, and 41.9% with post-traumatic events.

“The triangle sign was consistently present in all 36 eyes, with additional findings indicating concurrent VHs (52.8%) or RDs (5.6%). Among the 31 eyes with a total SCH, 58.3% initially had a detectable choroidal membrane seen on B-scans, while 41.7% did not. Despite this, the Triangle sign was consistently visible in all 36 eyes, and monitoring with B-scans revealed a choroidal membrane as the hemorrhage resolved,” the investigators reported.

They concluded that the triangle sign is valuable in that it is a “distinctive and reliable ultrasound feature” for diagnosing total CDs and SCHs. “The Triangle sign presents a promising preliminary finding as a diagnostic indicator for total CDs, offering clear anatomic and imaging distinctions that may help differentiate CDs from other ocular pathologies,” they said.

However, they cited the need for prospective, multicentre studies with control groups and statistical validation to confirm the sign’s reliability and accuracy of this sign and to explore its potential integration into routine clinical practice and standardise its application in diverse clinical settings.

References

1. Bhatt VD, Bhatt DC, Bhatt KD, et al. The “Triangle” Sign: A Novel Ultrasound Marker for Diagnosing Total Choroidal Detachment and Total Suprachoroidal Hemorrhage. Clin Ophthalmol. 2025;19:261-268; https://doi.org/10.2147/OPTH.S495062
   

2. Obuchowska I, Mariak Z. Choroidal detachment—pathogenesis, etiology and clinical features. Klin Oczna. 2005;107:529–532.
   

3. Hawkins WR, Chignell AH. Choroidal detachment. Am J Ophthalmol. 1972;74:994. doi:10.1016/0002-9394(72)91227-5
   

4. Diep MQ, Madigan MC. Choroidal detachments: what do optometrists need to know? Clin Exp Optom. 2019;102:116–125. doi:10.1111/cxo.12807
   

5. Rezende FA, Kickinger MC, Li G, Prado RF, Regis LG. Transconjunctival drainage of serous and hemorrhagic choroidal detachment. Retina. 2012;32:242–249. doi:10.1097/IAE.0b013e31821c4087
   

6. Bellows AR, Chylack LT, Hutchinson BT. Choroidal detachment. Clinical manifestation, therapy and mechanism of formation. Ophthalmology. 1981;88:1107–1115. doi:10.1016/S0161-6420(81)34897-0