High Incidence of Pelvic Deep Vein Thrombosis Detected by Magnetic Resonance Venograpy Post-Caesarean Section.
Bibliographic record
Abstract
Abstract Background Venous thromboembolism (VTE) is the leading cause of maternal mortality in the developed world. The post-partum period is the highest risk period for pregnancy associated VTE and delivery by Caesarean section further increases this risk. The true incidence of deep vein thrombosis (DVT) post- Caesarean section is unknown but felt to be low. The limited number of screening studies conducted to date have not included systematic pelvic vein imaging. Objectives To determine the incidence of DVT post-Caesarean section using Magnetic Resonance Venograpy (MRV) and bilateral compression ultrasounds. Methods Prospective cohort study of moderate to high risk women (one or more VTE risk factors) post-Caesarean section. On the day of post-partum discharge we conducted systematic bilateral proximal leg vein compression ultrasound imaging to detect proximal leg DVT and pelvic vein imaging with magnetic resonance venography (MRV). MRVs were independently and blindly interpreted by two radiologists with disagreements resolved by consensus. MRVs were interpreted as demonstrating definite, probable, possible or no thrombosis. Two rater Kappa scores were calculated from initial interpretations (prior to consensus review). Incidence of DVT and 95% confidence interval were calculated. Results Fifteen patients were recruited. At discharge, there were no proximal DVTs on bilateral leg compression ultrasounds. MRV results are shown in Table I. Conclusions The incidence of pelvic vein DVT post- Caesarean section is much higher than anticipated (46%). The clinical significance of this finding remains to be determined. However, diagnoses such as septic pelvic vein thrombophlebitis, which depend on demonstrating the presence pelvic vein thrombosis in the setting of post-partum fever may be falsely overdiagnosed. Pelvic vein thrombosis may be a common (and normal) finding post-Caesarean section. MRV may also prove to be a useful surrogate outcome measure in post-partum VTE prophylaxis studies. Table I: Pelvic Vein Imaging Results Post-C-Section MRV Consensus Result n/N (%) 95% CI Two Rater Kappa 95% CI= 95% Confidence Interval Definite Thrombosis 7/15 (46%) 21–73% 0.5 Definite or Probable Thrombosis 8/15 (53%) 27–79% 0.6 Definite, Probable or Possible Thrombosis 10/15 (66%) 38–88% 1.0 No Thrombosis 5/15 (33%) 12–62% 1.0
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.004 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| 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) | 0.003 | 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 source (direct Gemma or distilled Codex), 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".