Ultrasound imaging of extensive peripheral macrocysts in chronic total combined rhegmatogenous-traction retinal detachment.

Purpose: To report a case of a 42-year-old male with proliferative diabetic retinopathy (PDR) complicated by tractional retinal detachments (TRD) bilaterally with a rare finding on B-scan ultrasonography. Observations: On B-scan ultrasound, a total combined rhegmatogenous-TRD was observed, accompanied by extensive retinal macrocysts that appeared nearly confluent for 360°. Conclusions and Importance: Retinal macrocysts are rare but important clinical entities that help drive management, as their presence typically suggests a chronic retinal detachment.

Case report

A 42-year-old male with a past ocular history of proliferative diabetic retinopathy complicated by tractional retinal detachments bilaterally presented to clinic years since his last exam. The patient had undergone prior successful TRD repair in the right eye with stable 20/20 vision, while his left eye was deemed inoperable with longstanding light perception vision. Dilated fundoscopy in the left eye revealed a total combined rhegmatogenous-TRD accompanied by extensive peripheral macrocysts, with view limited by a dense cataract. B-scan ultrasonography of the left eye demonstrated a total retinal detachment (RD) with peripheral near-confluent anechoic hypodensities, confirming retinal macrocysts (Fig. 1A,B). Due to the severity and chronicity of the RD, observation with monocular precautions was recommended for the left eye.

Fig. 1

10 MHz B-scan ultrasonography probe of the left eye revealing chronic combined RRD-TRD (red arrows) with extensive peripheral macrocysts (blue arrows) at transverse 3 o'clock view (A). Transverse 6 o'clock view demonstrating highly reflective detached membrane as represented by steeply rising red spikes from baseline of superimposed A-scan (B).

Discussion

Uncontrolled proliferative diabetic retinopathy (PDR) can progress to serious ocular complications such as TRD or in this case, a combined rhegmatogenous-traction retinal detachment. Retinal detachments, when chronic in nature, typically present asymptomatically. Over time, the retinal layers can become hypoperfused and altered in metabolic activity, leading to permanent atrophy of the retinal pigment epithelium and its associated demarcation lines. Pathologic changes in response to RD include retinal neovascularization and cyst formation. Intraretinal cysts, when described as greater than 8–10 papillary disc diameters, are classified as macrocysts. Typically associated with chronic RD, macrocysts are a result of degenerative cystic changes and localized bifurcation of the outer plexiform layer of the detached retina.,

Intraretinal macrocysts are rare entities reported in 1–3% of RDs and often do not cause ocular symptoms or affect visual acuity. When visualized on fundus exam, they can be useful in determining appropriate management, as they often suggest a long-standing retinal detachment., On B-scan ultrasonography, macrocysts are described as near-confluent anechoic hypodensities with well-defined borders that can present as single or multiple entities in various shapes and sizes. Our patient's ultrasound revealed a combined rhegmatogenous-TRD accompanied by a rare pattern of extensive peripheral macrocysts that appeared nearly confluent for 360°. Similar echogenic findings can be seen in other retinal conditions such as juvenile retinoschisis syndrome, however said entities differ in that they typically present as complex cystic masses with a fluid-fluid level on B-scan.

Management of retinal macrocysts involves observation or repairing the co-existing RD, as successful RD repair usually leads to spontaneous resolution. If repair is indicated, retinal macrocysts can often be left uninterrupted and remain stable after surgery. In rare cases where macrocysts may interfere with retinal reattachment, surgical or laser-assisted drainage can usually lead to complete resolution. Due to our patient's long-standing severe RD with extremely low visual potential, surgery was not recommended. The patient was comfortable with his left eye and will continue observation with monocular precautions.

Conclusion

Retinal macrocysts, when detected on fundus exam or ultrasonography, are rare but important clinical entities that help drive appropriate management, as their presence typically suggests a chronic RD.

Funding

No funding or grant support.

Authorship

All authors attest that they meet the current ICMJE criteria for Authorship.

Patient consent

Consent to publish this case report has been obtained from the patient in writing.

Declaration of competing interest

The following authors have no financial disclosures: WL, SC.