Pierce eggplant with a fork; place on a baking sheet, and bake at 350 for 45 minutes or until tender.
Let cool; peel and finely chop.
Place a small nonstick skillet over medium-high heat until hot.
Add onion and garlic, and saut 3 minutes or until tender.
Combine eggplant, onion mixture, cheese, and next 9 ingredients (cheese through egg whites) in a large bowl; stir well. Crumble lamb over eggplant mixture, and stir just until ingredients are blended.
Pack meat mixture into an 8 x 4-inch loaf pan coated with cooking spray.
Bake at 350 for 1 hour and 10 minutes or until meat loaf registers 16
Let meat loaf stand in pan 10 minutes.
Remove meat loaf from pan; cut loaf into 12 slices.
Serve leftover meat loaf slices in pita bread halves with cucumber slices and plain low-fat yogurt.