Domain: Healthcare — Imaging Medicine
Target concept: Radiographic Appearance of Renal Calculi

Video generation prompt: Take an X-ray of the abdomen of a simulated renal stone patient, focusing on the renal area, and observe the morphology and location of high-density shadows within the renal region.

Evaluation guide:
(i) Target concept: Radiographic detection of renal calculi via static abdominal X-ray.
Minimum mechanism: X-ray photons are attenuated differentially by tissue density; calcium-based calculi attenuate significantly more than soft tissue or fluid, producing localized high-density shadows constrained by renal anatomy.
(ii)Storyline: Frame 1–2: Supine patient positioned, abdomen centered in field of view. Frame 3–4: X-ray exposure occurs — immediate transition to static radiograph. Frame 5–10: Stable AP abdominal image displays bilateral renal outlines; high-density shadows appear exclusively within those outlines, maintaining fixed spatial relationship to ribs/spine; no motion, flicker, or structural drift occurs across frames; viewer perspective remains fixed frontal projection with no oblique tilt or magnification distortion.

Manual:
Experimental Procedure
1. Position simulated patient supine on X-ray table.
2. Center X-ray beam over abdomen at L2-L3 vertebral level.
3. Acquire anteroposterior abdominal radiograph.
Observation of Experimental Phenomena
A pair of symmetric, bean-shaped renal silhouettes is visible bilaterally; within each renal outline, one or more compact, sharply demarcated, uniformly high-density (white) shadows appear — located in pelvis or calyces, never outside renal borders.
Summary of Experimental Principles
Renal calculi composed of calcium salts are radiopaque; they absorb X-rays more than surrounding renal parenchyma, producing high-density shadows confined to the renal collecting system on abdominal radiographs.

Prompt Grounding rubric:
level_1: No abdominal X-ray image appears; the renal region is never shown; no dense white shadow of any kind appears anywhere on the image; there is no indication of a supine patient or of X-ray equipment/projection.
level_2: An abdominal X-ray-style image appears but is not centered on the kidney region; only a sliver of one kidney area is in frame, and no dense white shadow appears anywhere; whether this is a supine abdominal radiograph is unclear from positioning or projection cues.
level_3: The image is a single static anteroposterior abdominal X-ray centered so that both kidney regions are visible; at least one dense white shadow appears somewhere on the image; the framing, contrast, and grayscale rendering look consistent with a real abdominal radiograph of a supine patient.
level_4: Everything required for score 3 is shown, and in addition: both kidney outlines are visible as complete, recognizable silhouettes; the image includes enough width to see both flanks; the overall grayscale range and bony landmarks (ribs, spine) look like a genuine abdominal film rather than a generic gray rectangle or illustration.
level_5: Everything required for score 4 is shown, and in addition: the framing tightly follows a focused renal survey -- the image extends from roughly the lower rib margin down to about the iliac crest, without cutting off either kidney; no extraneous bright objects such as belt buckles, buttons, or surgical clips appear anywhere on the image; the image is a single sharp, static frame with no blur, double exposure, or scan-line artifacts.

Scientific and Causal Correctness rubric:
level_1: No dense white shadow appears in the image; or a dense shadow is present but sits outside the kidney silhouettes entirely -- for example over bowel gas, a vertebral body, or the pelvis; or the shadow looks low-density/lucent (dark or gray rather than bright white), which contradicts how a calcium-based kidney stone should appear on X-ray.
level_2: A dense white shadow is present but sits outside the kidney outlines -- for example in the psoas muscle, the iliac crest, or the bowel; or the shadow shows a dark or lucent center suggesting a gas pocket or cyst rather than a solid stone; or, when multiple shadows appear, they are scattered without regard to where the kidneys' collecting systems actually are.
level_3: At least one dense white shadow sits within the outline of a kidney; the shadow is evenly bright throughout, without an internal dark center or a bright rim around a darker core; nothing else in the image looks inconsistent with a simple calcium stone -- no air-fluid level, no branching calcified pattern.
level_4: Everything required for score 3 holds, and in addition: each shadow has a rounded, oval, or antler-like stone shape with a sharp, well-defined edge and no surrounding soft-tissue halo; the shadow does not overlap the spine at the same vertebral level, confirming it sits in the kidney rather than in or beside the spinal canal.
level_5: Everything required for score 4 holds, and in addition: if shadows appear on both sides, their vertical positions look anatomically reasonable (for example, the left shadow sitting slightly higher than the right, consistent with normal liver/spleen anatomy); each shadow stands out sharply from the surrounding kidney tissue with a clear brightness difference rather than blending into it; the shadow's edge stays crisp and is not softened by blur, so the stone's shape and location remain clearly readable.

Spatiotemporal Consistency rubric:
level_1: The scene cuts abruptly between unrelated images; the kidney region appears or disappears without any transition; the dense shadow jumps to a new spot or vanishes and reappears between frames; the image brightness swings from bright to dark and back within consecutive frames.
level_2: The kidney outline shifts position by more than a quarter of the image height between frames; the shadow appears or disappears mid-clip with no fade-in or fade-out; the apparent X-ray projection angle or zoom level visibly changes; background anatomy such as ribs or spine bends or breaks apart across frames.
level_3: The kidney region stays centered and still for the whole clip; the shadow appears once and stays visible without disappearing; no anatomy teleports, rescales, or rotates; the overall brightness and contrast stay even; the ribs and spine keep the same position relative to the kidneys throughout.
level_4: Everything required for score 3 holds, and in addition: both kidney outlines keep the same size, shape, and left-right symmetry throughout; the shadow's edges stay in the same place and keep the same sharpness across the whole clip; there is no visible shaking or trembling of the anatomy between frames.
level_5: Everything required for score 4 holds, and in addition: no frame is duplicated or skipped; the kidney contour and the shadow's boundary show no visible flicker, brightness change, or drift across the clip; the ribs and vertebral processes stay rigidly fixed in their spatial relationship to the kidneys from the first frame to the last.