Re: Non‐visualization of the cavum septi pellucidi is not synonymous with agenesis of the corpus callosum. G. Malinger, D. Lev, M. Oren and T. Lerman‐Sagie. <i>Ultrasound Obstet Gynecol</i> 2012; 40: 165–170.
Bibliographic record
Abstract
The cavum septi pellucidi (CSP) et Vergae is the hypoechoic fluid-containing rectangular space between the as yet unfused laminae of the septum pellucidum on standard axial views of the head until septal fusion occurs, typically in the third trimester, forming the single septum pellucidum. The utility and importance of CSP identification at prenatal ultrasound as a marker for normal development of midline structures including the corpus callosum has been affirmed by several investigators1. Failure to demonstrate the normal CSP at the mid-trimester anatomy scan should trigger detailed assessment of the brain and other anatomy and consideration of counseling and further investigations. What remains as a clinical problem is the significance of alterations in the appearance of the CSP, including unexpectedly large or small size and alteration in the appearance of its contents. In this issue of the Journal, Malinger and colleagues have reviewed the unusual occurrence of failure to see fluid in the CSP, in fetuses evaluated from 22 to 35 gestational weeks. It is reassuring that in most cases the finding was isolated and followed by normal outcome. Nonetheless, a few cases had problems, reaffirming the approach that any deviation from normal appearance should lead to further assessment. The embryology of the corpus callosum (CC) and CSP is complex2, 3. An issue that Malinger et al. raise is the range of normal sonographic appearances of the septa, CSP and fornices around the time of their initial formation in early pregnancy. Embryological reviews suggest that even up to 17–20 weeks the septal walls may be quite thick and leave little space for fluid2, 4. In contrast, at ultrasound, the CSP is described as a clear box with thin walls (septa) that become visible in some fetuses as early as 15 weeks and in all normal fetuses by 16–18 weeks5. Clarification of the normal early developmental sonographic appearance of this region is especially relevant today, with the increased emphasis on early anatomical assessment using very high-resolution transvaginal probes and multiple views (coronal and sagittal). Until clarification is achieved, caution should be exercised regarding counseling related to suspected CSP/CC variations prior to 18 gestational weeks. It is important to remember that as new and ever more sophisticated transducers and image processing are introduced, ‘new’ unexpected findings will be observed. These should be reported and managed with caution until their significance is established. A. Toi*, * University of Toronto, Princess Margaret Hospital, 610 University Avenue, Room 4-833, Toronto, Canada, M5G 2M9
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 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 | 0.012 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| 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".