Acute choke zone effects: Lessons from radioactive and fluorescent microspheres in a pig model muscle flap
Bibliographic record
Abstract
BACKGROUND: Choke vessels dilate and contract to regulate blood flow between adjacent arterial angiosomes. In skin flap surgery, when arterial inflow to an angiosome is ligated, choke vessels allow blood supply from an adjacent angiosome. In muscle flap surgery, the vascular anatomy is analogous to skin flaps; however, while it is established that the choke vessels will fully dilate irreversibly after two to three days, no study has yet analyzed the acute changes in each vascular region immediately following ligation of one pedicle. OBJECTIVE: To establish whether the choke vessels open or close immediately following ligation of a pedicle, and how this change affects blood flow in the adjacent proximal and distal vascular regions. METHODS: Radioactive and fluorescent microspheres in a pig model were used to study the regional intramuscular blood flow in each anatomical zone of a rectus abdominis flap. Blood flow measurements for each zone were calculated relative to the entire muscle at preligation, ligation and various times (15 min to 90 min) postligation. RESULTS: There was no statistically significant difference in blood flow across choke zones as a result of ligation. This signifies that the choke vessels do not significantly dilate to produce a statistically significant measureable change in blood flow. CONCLUSIONS: Given these results and previous literature findings, the anatomical presence of choke vessels in a muscle is the strongest determining factor for acute flap viability in surgery.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".