## **Core Concept**
Pathological myopia, also known as malignant or progressive myopia, is a severe form of myopia that can lead to significant visual impairment. It is characterized by an elongated eyeball and thinning of the sclera, retina, and choroid. Complications arise due to the structural changes and stretching of the ocular tissues.

## **Why the Correct Answer is Right**
The most common complication of pathological myopia is **retinal detachment**. This occurs due to the thinning and stretching of the retina, which can lead to tears and subsequent detachment from the retinal pigment epithelium. The risk is higher in pathological myopia due to the extensive retinal thinning and scleral ectasia. Retinal detachment is a serious condition that can lead to severe vision loss if not promptly treated.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Cataract formation, while possible in myopic eyes, is not the most direct or common complication specifically attributed to pathological myopia compared to retinal detachment.
- **Option B:** Glaucoma can be associated with myopia, but it is not as directly related to the structural complications of pathological myopia as retinal detachment.
- **Option C:** (Assuming this is not the correct answer) Other complications like maculopathy or choroidal neovascularization can occur but are not as commonly associated with pathological myopia as retinal detachment.

## **Clinical Pearl / High-Yield Fact**
A key clinical pearl is that patients with pathological myopia are at a significantly increased risk of retinal detachment. Regular ophthalmological follow-ups are crucial for early detection and prevention of complications. A classic sign to look out for is the "myopic crescent" or "temporal crescent," which can indicate areas of retinal thinning.

## **Correct Answer:** D. Retinal detachment.