A Randomized Comparison Between Ultrasound- and Fluoroscopy-Guided Third Occipital Nerve Block
Bibliographic record
Abstract
BACKGROUND: Third occipital nerve block (TONB) is commonly used in the diagnosis and treatment of upper neck pain and cervicogenic headaches. Although fluoroscopy is the current imaging standard for TONB, ultrasound (US) guidance offers a promising, radiation-free alternative. In this randomized, observer-blinded trial, we compared the 2 imaging modalities. Our research hypothesis was that US guidance would result in a shorter performance time. METHODS: Forty patients undergoing TONB were randomized to fluoroscopy or US guidance. A mixture of local anesthetic and radiographic contrast was injected in both groups. The primary outcome was performance time. Secondary outcomes included success rate, pain levels before and after block, area of sensory hypoesthesia, quality of the block (assessed by electrical perceptual threshold), and procedure-related complications. RESULTS: Ultrasound guidance was associated with a significantly shorter performance time (212.8 vs 396.5 seconds; P = 0.000) and fewer needle passes (2 vs 6; P = 0.000). Both imaging modalities, however, resulted in similar success rates (95%-100%). Furthermore, no intergroup differences were found in preblock and postblock pain scores. In both groups, TONB produced hypoesthesia that was most profound in the suboccipital region. In the fluoroscopy group, C2-C3 intra-articular spread of radiographic contrast and vascular breach were noted in 15% and 10% of patients, respectively. In contrast, no adverse events occurred with US guidance. CONCLUSIONS: Fluoroscopy and US guidance provide similar success rates for TONB. However, ultrasonography is associated with improved efficiency (decreased performance time, fewer needle passes).
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 | 0.005 | 0.010 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.004 | 0.002 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.002 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.003 | 0.002 |
| Insufficient payload (model declined to judge) | 0.009 | 0.001 |
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".