# Villalta post-thrombotic syndrome scale Villalta Status: LIVE Price: $0.005 USDC `GET /api/calc/villalta` HTML: https://magentlab.com/docs/villalta Markdown: https://magentlab.com/docs/villalta.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum five caller-assigned Villalta symptoms and six signs (each integer 0-3) and return the Kahn 2009 PTS band. Venous ulcer is a separate boolean and is not added as 15 points. ## When to use When an agent has already assigned Kahn 2009 0-3 integers for the eleven items and a venous-ulcer flag and needs the published total and PTS band, not a limb exam, CEAP, VCSS, or Ginsberg PTS. ## When not to use - Not a medical device and not a PTS diagnosis, anticoagulation, or compression order. magent does not examine the limb. - Each of the eleven items is a caller-assigned integer 0-3 (0 none, 1 mild, 2 moderate, 3 severe). Venous ulcer is a separate boolean and is not added as 15 points to the numeric score. - Kahn 2009 ISTH SSC bands: none 0-4 without ulcer; mild 5-9; moderate 10-14; severe if score ≥15 or ulcer is present even when the sum is <15. - Not CEAP, not VCSS, and not Ginsberg PTS. ## Formula ``` Villalta = pain + cramps + heaviness + pruritus + paresthesia + pretibial_edema + skin_induration + hyperpigmentation + venous_ectasia + redness + pain_on_calf_compression; each caller-assigned 0-3; max 33; ulcer is a separate boolean and is not added to the score; PTS if score ≥5 or ulcer; none 0-4 (no ulcer); mild 5-9; moderate 10-14; severe if score ≥15 or ulcer ``` ## Citation [Measurement properties of the Villalta scale to define and classify the severity of the post-thrombotic syndrome](https://doi.org/10.1111/j.1538-7836.2009.03339.x) Kahn SR J Thromb Haemost. 2009;7(5):884-888 DOI: [10.1111/j.1538-7836.2009.03339.x](https://doi.org/10.1111/j.1538-7836.2009.03339.x) ## Worked example ### All items 0, no ulcer Given: `cramps=0, heaviness=0, hyperpigmentation=0, pain=0, pain_on_calf_compression=0, paresthesia=0, pretibial_edema=0, pruritus=0, redness=0, skin_induration=0, ulcer=false, venous_ectasia=0` 1. Five symptoms 0 + six signs 0; ulcer false is not added to the score 2. Score = 0 (max 33); pts = false; pts_band none ### All items 0, ulcer present Given: `cramps=0, heaviness=0, hyperpigmentation=0, pain=0, pain_on_calf_compression=0, paresthesia=0, pretibial_edema=0, pruritus=0, redness=0, skin_induration=0, ulcer=true, venous_ectasia=0` 1. Score remains 0; ulcer does not add 15 2. pts = true; pts_band severe because ulcer is present ## Also searched as - Villalta scale - Villalta PTS - post-thrombotic syndrome - Kahn Villalta - Villalta score - ISTH Villalta - venous PTS scale - postthrombotic syndrome Villalta ## Parameters - `pain` (integer, required): Caller-assigned Kahn 2009 Villalta symptom pain (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `cramps` (integer, required): Caller-assigned Kahn 2009 Villalta symptom cramps (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `heaviness` (integer, required): Caller-assigned Kahn 2009 Villalta symptom heaviness (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `pruritus` (integer, required): Caller-assigned Kahn 2009 Villalta symptom pruritus (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `paresthesia` (integer, required): Caller-assigned Kahn 2009 Villalta symptom paresthesia (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `pretibial_edema` (integer, required): Caller-assigned Kahn 2009 Villalta sign pretibial edema (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `skin_induration` (integer, required): Caller-assigned Kahn 2009 Villalta sign skin induration (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `hyperpigmentation` (integer, required): Caller-assigned Kahn 2009 Villalta sign hyperpigmentation (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `venous_ectasia` (integer, required): Caller-assigned Kahn 2009 Villalta sign venous ectasia (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `redness` (integer, required): Caller-assigned Kahn 2009 Villalta sign redness (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `pain_on_calf_compression` (integer, required): Caller-assigned Kahn 2009 Villalta sign pain on calf compression (integer 0-3: 0 none, 1 mild, 2 moderate, 3 severe). magent does not examine the limb. - `ulcer` (boolean, required): Caller-assigned venous ulcer (true or false). Presence classifies PTS as severe (Kahn 2009) and does not add 15 to the numeric score. magent does not examine the limb. ## Bulk (POST) POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement. Method: `POST /api/calc/villalta` Max items: 25 Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic) Status: PREVIEW - 1 to 25 items. Each item uses the same keys as the GET query parameters. - POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows. - The first invalid item fails the whole request (index in the 400 JSON). You are not charged. - HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row. - Catalog misses (empty matches, found=false) stay paid 200s inside that slot. - x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items. Example request: ```json { "items": [ { "cramps": "0", "heaviness": "0", "hyperpigmentation": "0", "pain": "0", "pain_on_calf_compression": "0", "paresthesia": "0", "pretibial_edema": "0", "pruritus": "0", "redness": "0", "skin_induration": "0", "ulcer": "false", "venous_ectasia": "0" }, { "cramps": "0", "heaviness": "0", "hyperpigmentation": "0", "pain": "0", "pain_on_calf_compression": "0", "paresthesia": "0", "pretibial_edema": "0", "pruritus": "0", "redness": "0", "skin_induration": "0", "ulcer": "false", "venous_ectasia": "0" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/villalta Example 200: ```json { "count": 2, "path": "/api/calc/villalta", "items": [ { "components": [ { "value": 0, "factor": "pain", "points": 0, "present": true }, { "value": 0, "factor": "cramps", "points": 0, "present": true }, { "value": 0, "factor": "heaviness", "points": 0, "present": true }, { "value": 0, "factor": "pruritus", "points": 0, "present": true }, { "value": 0, "factor": "paresthesia", "points": 0, "present": true }, { "value": 0, "factor": "pretibial_edema", "points": 0, "present": true }, { "value": 0, "factor": "skin_induration", "points": 0, "present": true }, { "value": 0, "factor": "hyperpigmentation", "points": 0, "present": true }, { "value": 0, "factor": "venous_ectasia", "points": 0, "present": true }, { "value": 0, "factor": "redness", "points": 0, "present": true }, { "value": 0, "factor": "pain_on_calf_compression", "points": 0, "present": true } ], "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Kahn SR", "doi": "10.1111/j.1538-7836.2009.03339.x", "id": "kahn-2009", "pmid": "19320818", "source": "J Thromb Haemost. 2009;7(5):884-888", "title": "Measurement properties of the Villalta scale to define and classify the severity of the post-thrombotic syndrome" }, "formula": "villalta", "formula_expression": "Villalta = pain + cramps + heaviness + pruritus + paresthesia + pretibial_edema + skin_induration + hyperpigmentation + venous_ectasia + redness + pain_on_calf_compression; each caller-assigned 0-3; max 33; ulcer is a separate boolean and is not added to the score; PTS if score ≥5 or ulcer; none 0-4 (no ulcer); mild 5-9; moderate 10-14; severe if score ≥15 or ulcer", "max_score": 33, "score": 0, "pts": false, "pts_band": "none", "ulcer": false }, { "components": [ { "value": 0, "factor": "pain", "points": 0, "present": true }, { "value": 0, "factor": "cramps", "points": 0, "present": true }, { "value": 0, "factor": "heaviness", "points": 0, "present": true }, { "value": 0, "factor": "pruritus", "points": 0, "present": true }, { "value": 0, "factor": "paresthesia", "points": 0, "present": true }, { "value": 0, "factor": "pretibial_edema", "points": 0, "present": true }, { "value": 0, "factor": "skin_induration", "points": 0, "present": true }, { "value": 0, "factor": "hyperpigmentation", "points": 0, "present": true }, { "value": 0, "factor": "venous_ectasia", "points": 0, "present": true }, { "value": 0, "factor": "redness", "points": 0, "present": true }, { "value": 0, "factor": "pain_on_calf_compression", "points": 0, "present": true } ], "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Kahn SR", "doi": "10.1111/j.1538-7836.2009.03339.x", "id": "kahn-2009", "pmid": "19320818", "source": "J Thromb Haemost. 2009;7(5):884-888", "title": "Measurement properties of the Villalta scale to define and classify the severity of the post-thrombotic syndrome" }, "formula": "villalta", "formula_expression": "Villalta = pain + cramps + heaviness + pruritus + paresthesia + pretibial_edema + skin_induration + hyperpigmentation + venous_ectasia + redness + pain_on_calf_compression; each caller-assigned 0-3; max 33; ulcer is a separate boolean and is not added to the score; PTS if score ≥5 or ulcer; none 0-4 (no ulcer); mild 5-9; moderate 10-14; severe if score ≥15 or ulcer", "max_score": 33, "score": 0, "pts": false, "pts_band": "none", "ulcer": false } ] } ``` ## Response fields - `formula` (string): villalta - `formula_expression` (string): Exact expression used - `score` (integer): Sum of the eleven Kahn 2009 items (0-33). Venous ulcer is not added as 15 points. - `max_score` (integer): Always 33 - `pts` (boolean): true when score ≥5 or ulcer is true (Kahn 2009 PTS definition) - `pts_band` (string): Kahn 2009 band: none (0-4 and no ulcer), mild (5-9), moderate (10-14), or severe (score ≥15 or ulcer). Not a treatment order. - `ulcer` (boolean): Caller-assigned venous ulcer used. Presence classifies severe PTS and does not change score. - `components` (array): Per-item caller-assigned points - `citation` (object): Kahn 2009 J Thromb Haemost citation (ISTH SSC supporting review) - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "value": 0, "factor": "pain", "points": 0, "present": true }, { "value": 0, "factor": "cramps", "points": 0, "present": true }, { "value": 0, "factor": "heaviness", "points": 0, "present": true }, { "value": 0, "factor": "pruritus", "points": 0, "present": true }, { "value": 0, "factor": "paresthesia", "points": 0, "present": true }, { "value": 0, "factor": "pretibial_edema", "points": 0, "present": true }, { "value": 0, "factor": "skin_induration", "points": 0, "present": true }, { "value": 0, "factor": "hyperpigmentation", "points": 0, "present": true }, { "value": 0, "factor": "venous_ectasia", "points": 0, "present": true }, { "value": 0, "factor": "redness", "points": 0, "present": true }, { "value": 0, "factor": "pain_on_calf_compression", "points": 0, "present": true } ], "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Kahn SR", "doi": "10.1111/j.1538-7836.2009.03339.x", "id": "kahn-2009", "pmid": "19320818", "source": "J Thromb Haemost. 2009;7(5):884-888", "title": "Measurement properties of the Villalta scale to define and classify the severity of the post-thrombotic syndrome" }, "formula": "villalta", "formula_expression": "Villalta = pain + cramps + heaviness + pruritus + paresthesia + pretibial_edema + skin_induration + hyperpigmentation + venous_ectasia + redness + pain_on_calf_compression; each caller-assigned 0-3; max 33; ulcer is a separate boolean and is not added to the score; PTS if score ≥5 or ulcer; none 0-4 (no ulcer); mild 5-9; moderate 10-14; severe if score ≥15 or ulcer", "max_score": 33, "score": 0, "pts": false, "pts_band": "none", "ulcer": false } ``` ## Errors - HTTP 400 `invalid_villalta`: each Villalta symptom and sign must be an integer 0-3 (Kahn 2009 ISTH; 0 none, 1 mild, 2 moderate, 3 severe). Returned before settlement; you are not charged. - HTTP 400 `invalid_flag`: boolean clinical flags must be true or false Returned before settlement; you are not charged. - HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged. - HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged. - HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged. Shared HTTP 402 and 503: https://magentlab.com/docs/payments ## Related tools - [IMPROVE VTE](https://magentlab.com/docs/improve-vte) — Compute the Spyropoulos 2011 7-factor associative IMPROVE VTE score during hospitalization from age and six caller-assigned flags. ## Payment Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. - GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall). - HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote. - Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering. - Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional. - Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402. - offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront. - offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization. - not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search. Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers). Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments Stdio MCP (one process per host): https://magentlab.com/docs/mcp ## Guarantees - HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON. - exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE. - HTTP 402 is unpaid only. Do not sign a second authorization because of a 503. - Execution is timeout-bounded and concurrency-capped. - Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.