A 52-year-old man presents with sudden onset floaters and flashing lights in the right eye for 2 days. Examination reveals a superior temporal retinal detachment with macula still attached. B-scan ultrasonography confirms rhegmatogenous retinal detachment. What is the drug of choice for pneumatic retinopexy in this case?

Explanation

## Pneumatic Retinopexy: Gas Selection **Key Point:** Sulfur hexafluoride (SF₆) is the drug of choice for pneumatic retinopexy in uncomplicated rhegmatogenous retinal detachment with superior or superior temporal breaks and macula-on status. ### Rationale for SF₆ in This Case 1. **Break Location**: Superior temporal break — ideal for SF₆ because the gas bubble naturally rises and tamponades superior breaks by gravity. 2. **Macula-On Status**: Requires rapid visual rehabilitation; SF₆ expands to ~2× original volume and lasts 1–2 weeks, allowing faster visual recovery than longer-acting gases. 3. **Simplicity**: Requires only head positioning (face-down or specific gaze direction) without need for vitrectomy. ### Gas Expansion & Duration Comparison | Gas | Expansion Factor | Duration | Best Use | |-----|------------------|----------|----------| | **SF₆** | ~2× | 1–2 weeks | Superior breaks, macula-on, simple cases | | **C₂F₆** | ~4× | 6–8 weeks | Inferior breaks, multiple breaks | | **C₃F₈** | ~4× | 8–12 weeks | Complex detachments, inferior breaks, PVR | | **Silicone oil** | Permanent | Indefinite | Severe PVR, inferior breaks, multiple surgeries | **High-Yield:** SF₆ is the **smallest and fastest-resorbing** gas; it is ideal for macula-on detachments because patients regain vision within 2–3 weeks. Longer-acting gases (C₃F₈) are reserved for more complex or inferior detachments where prolonged tamponade is needed. **Clinical Pearl:** Patients must maintain strict head positioning (face-down or specific gaze) for 10–14 days to keep the gas bubble against the retinal break. This is a critical patient counseling point — non-compliance leads to failure. **Warning:** SF₆ is contraindicated if the patient requires air travel within 2 weeks (gas expansion at altitude can cause catastrophic intraocular pressure rise). Always ask about planned travel before selecting SF₆. ## Why Other Gases Are Not First-Line Here **Perfluoropropane (C₃F₈)** is longer-acting and used for inferior breaks or complex detachments with proliferative vitreoretinopathy (PVR), not for simple superior macula-on cases. **Perfluoroethane (C₂F₆)** is intermediate in duration and used when SF₆ would be too short but C₃F₈ unnecessarily long — not indicated for this straightforward case. **Silicone oil** is reserved for severe PVR, inferior breaks, or when multiple surgeries are anticipated; it is not a gas and requires formal vitrectomy.