Pith Number

pith:HILXOGON

pith:2026:HILXOGON3ZU6SXYTEJ2P7NME6C

not attested not anchored not stored refs pending

Lost in Volume: The CT-SpatialVQA Benchmark for Evaluating Semantic-Spatial Understanding of 3D Medical Vision-Language Models

Asif Hanif, Mashrafi Monon, Mohammad Yaqub, Numan Saeed, Umaima Rahman

3D medical vision-language models struggle with semantic-spatial reasoning in CT volumes, averaging just 34% accuracy on a new benchmark.

arxiv:2605.08787 v2 · 2026-05-09 · cs.CV

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\usepackage{pith}
\pithnumber{HILXOGON3ZU6SXYTEJ2P7NME6C}

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Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Claims

C1strongest claim

We introduce CT-SpatialVQA, a benchmark designed to evaluate semantic-spatial reasoning in 3D CT data. [...] finding severe degradation on semantic-spatial reasoning tasks, averaging 34% accuracy and often below random.

C2weakest assumption

The constructed QA pairs require and test explicit 3D volumetric spatial reasoning rather than being solvable through 2D projections, language correlations, or learned priors alone.

C3one line summary

CT-SpatialVQA benchmark shows 3D medical VLMs achieve only 34% average accuracy on semantic-spatial reasoning tasks in CT volumes, often below random chance.

Formal links

1 machine-checked theorem link

Receipt and verification

First computed	2026-06-23T01:12:07.993098Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

3a177719cdde69e95f132274ffb584f080522d53d2d67b16b6acfaf07195db1f

Aliases

arxiv: 2605.08787 · arxiv_version: 2605.08787v2 · doi: 10.48550/arxiv.2605.08787 · pith_short_12: HILXOGON3ZU6 · pith_short_16: HILXOGON3ZU6SXYT · pith_short_8: HILXOGON

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/HILXOGON3ZU6SXYTEJ2P7NME6C \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 3a177719cdde69e95f132274ffb584f080522d53d2d67b16b6acfaf07195db1f

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "eb884e6bd20c8c8cbabb1b7cc36a15d0b0c39869635f045a703478de6765c51e",
    "cross_cats_sorted": [],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "cs.CV",
    "submitted_at": "2026-05-09T08:16:00Z",
    "title_canon_sha256": "d7f8326f6cd8694a50572ccc9a3db7a73dc1a5484414c75c209e26c33b0ee907"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2605.08787",
    "kind": "arxiv",
    "version": 2
  }
}