A 52-year-old woman with type 2 diabetes (HbA1c 9.2%) presents with acute onset blurred vision in the right eye over 3 days. On slit-lamp examination, she has fine vacuoles in the anterior and posterior cortex of the lens with a characteristic 'sunflower' appearance on retroillumination. Visual acuity is 6/12. What is the most appropriate next step in management?

Explanation

## Clinical Diagnosis This patient has an **acute diabetic cataract** (also called **true diabetic cataract** or **osmotic cataract**). The 'sunflower' appearance and acute onset with poor glycaemic control are pathognomonic. ## Pathophysiology of Diabetic Cataract **Key Point:** Acute diabetic cataracts are caused by osmotic stress from hyperglycaemia. Excess glucose enters the lens via GLUT1 transporter, is converted to sorbitol by aldose reductase, and accumulates intracellularly (sorbitol cannot exit the lens). Water follows osmotically, causing lens fibre swelling, disruption, and cortical vacuole formation. **High-Yield:** Unlike mature cataracts, acute diabetic cataracts are **potentially reversible** if glycaemic control is restored early. The lens changes are functional (osmotic swelling) rather than structural (protein denaturation). ## Natural History & Management | Feature | Acute Diabetic Cataract | Mature Cataract | |---------|------------------------|------------------| | Onset | Acute (days to weeks) | Insidious (months to years) | | Reversibility | **Reversible with glycaemic control** | Irreversible | | Pathology | Osmotic swelling (sorbitol accumulation) | Protein denaturation & cross-linking | | Management | Glycaemic control first | Surgery | | Prognosis | Vision may improve | Requires surgery | **Clinical Pearl:** In a young patient with poor glycaemic control and acute cataract, **always optimize diabetes management first**. Many of these cataracts regress partially or completely with tight glycaemic control over weeks to months. Surgery should be deferred unless vision loss is severe and glycaemic control fails to improve the cataract. ## Why Optimize Glycaemic Control? 1. **Reversibility potential**: Acute osmotic cataracts can improve with glucose normalization 2. **Avoid unnecessary surgery**: Patient is only 52 years old; preserving native lens is preferable 3. **Reduce surgical risk**: Poor glycaemic control increases post-operative infection and delayed healing 4. **Evidence-based**: Standard management of acute diabetic cataract is metabolic control, not surgery **Mnemonic:** **ACUTE** Diabetic Cataract: - **A**cute onset (days–weeks) - **C**ontrol glucose first - **U**nderstand osmotic mechanism - **T**reatment is metabolic, not surgical - **E**xpect potential reversal