{
  "imageId": "ceph_001",
  "gender": "male",
  "landmarks": [
    { "id": "S", "label": "Sella", "x": 140.0, "y": 130.0 },
    { "id": "N", "label": "Nasion", "x": 150.0, "y": 100.0 },
    { "id": "A", "label": "Point A", "x": 160.0, "y": 200.0 },
    { "id": "B", "label": "Point B", "x": 170.0, "y": 250.0 },
    { "id": "Gn", "label": "Gnathion", "x": 180.0, "y": 300.0 },
    { "id": "Go", "label": "Gonion", "x": 120.0, "y": 310.0 }
  ],
  "analysisGroups": [
    {
      "name": "Steiner",
      "description": "Steiner analysis is a cephalometric method used to evaluate anteroposterior relationships of the maxilla and mandible to the cranial base.",
      "analyses": [
        {
          "id": "SNA",
          "type": "angle",
          "description": "Measures the anteroposterior position of the maxilla relative to the cranial base.",
          "points": ["S", "N", "A"],
          "vertex": "N",
          "arms": ["S", "A"],
          "value": 82.5,
          "unit": "degrees",
          "norm": {
            "reference": "Steiner 1953",
            "mean": 82.0,
            "std_dev": 2.0,
            "range": [80.0, 84.0],
            "unit": "degrees",
            "interpretation": "normal"
          }
        },
        {
          "id": "SNB",
          "type": "angle",
          "description": "Measures the anteroposterior position of the mandible relative to the cranial base.",
          "points": ["S", "N", "B"],
          "vertex": "N",
          "arms": ["S", "B"],
          "value": 80.0,
          "unit": "degrees",
          "norm": {
            "reference": "Steiner 1953",
            "mean": 80.0,
            "std_dev": 2.0,
            "range": [78.0, 82.0],
            "unit": "degrees",
            "interpretation": "normal"
          }
        }
      ],
      "curves": [
        {
          "id": "mandibular_border",
          "description": "Mandibular lower border traced for mandibular plane angle calculation.",
          "type": "curve",
          "algorithm": "spline",
          "closed": false,
          "points": [
            { "id": "Go" },
            { "x": 130.5, "y": 290.0 },
            { "id": "Gn" }
          ]
        }
      ]
    },
    {
      "name": "McNamara",
      "description": "McNamara analysis focuses on the sagittal relationship of jaws and airway evaluation.",
      "analyses": [
        {
          "id": "Nperp-Pg",
          "type": "length",
          "description": "Distance from Pogonion to a perpendicular from Nasion",
          "points": ["N", "Pg"],
          "value": 4.0,
          "unit": "mm",
          "norm": {
            "reference": "McNamara 1984",
            "mean": 2.0,
            "std_dev": 1.0,
            "range": [1.0, 3.0],
            "unit": "mm",
            "interpretation": "slightly forward"
          }
        }
      ],
      "curves": [
        {
          "id": "palatal_plane",
          "description": "Curve representing the hard palate.",
          "type": "curve",
          "algorithm": "bezier",
          "closed": false,
          "points": [
            { "id": "ANS" },
            { "x": 145.0, "y": 190.0 },
            { "id": "PNS" }
          ]
        }
      ]
    }
  ]
}