Can cavum septum pellucidum width and length measurements also be reliable indicators of corpus callosum measurements in normal fetuses?

OBJECTIVE: To examine the association between cavum septum pellucidum (CSP) and corpus callosum (CC) length and width measurements in mid-trimester sonographic screening in normal fetuses. METHODS: This prospective cohort study examined 152 pregnant women who underwent mid-trimester sonographic fetal anomaly screening. CSP and CC lengths and their anterior, middle, and posterior width measurements were examined sonographically. The association between length and width measurements of both structures, gestational week and CSP ratio (length/width) were evaluated. RESULTS: The mean CSP length was 7.96 ± 1.09 mm, and the mean middle width was 3.43 ± 0.82 mm. The mean CC length was 20 ± 3.76 mm, and the mean middle width was 3.43 ± 0.82 mm. There was a positive correlation between CSP and CC lengths (r = 0.691, p < 0.001). There was also a significant correlation between CSP and CC anterior, middle and posterior widths (anterior (r = 0.366, p < 0.001), middle (r = 0.305, p < 0.001), and posterior (r = 0.233, p = 0.004)). All CSP and CC measurements were correlated with gestational age, biparietal diameter (BPD), and head circumference (HC) (p < 0.001, for all). The CSP ratio was not related to CC dimensions (p > 0.05, for all) and also decreased with the increase in BPD and HC dimensions (r = -0.186, p = 0.022, and r = -0.174, p = 0.032; respectively). CONCLUSION: In normal fetuses, the length and width of the CC and CSP structures developed in relation to each other, as well as to the gestational week, BPD, and HC dimensions. In addition, while the CSP ratio was not found to be associated with CC dimensions, it decreased due to the increase in BPD and HC sizes.

White and Gray Matter Abnormalities in Australian Footballers With a History of Sports-Related Concussion: An MRI Study.

Sports-related concussion (SRC) is a form of mild traumatic brain injury that has been linked to long-term neurological abnormalities. Australian rules football is a collision sport with wide national participation and is growing in popularity worldwide. However, the chronic neurological consequences of SRC in Australian footballers remain poorly understood. This study investigated the presence of brain abnormalities in Australian footballers with a history of sports-related concussion (HoC) using multimodal MRI. Male Australian footballers with HoC (n = 26), as well as noncollision sport athletes with no HoC (n = 27), were recruited to the study. None of the footballers had sustained a concussion in the preceding 6 months, and all players were asymptomatic. Data were acquired using a 3T MRI scanner. White matter integrity was assessed using diffusion tensor imaging. Cortical thickness, subcortical volumes, and cavum septum pellucidum (CSP) were analyzed using structural MRI. Australian footballers had evidence of widespread microstructural white matter damage and cortical thinning. No significant differences were found regarding subcortical volumes or CSP. These novel findings provide evidence of persisting white and gray matter abnormalities in Australian footballers with HoC, and raise concerns related to the long-term neurological health of these athletes.

What Are the Double Lines of the Fetal Cavum Septi Pellucidi on Ultrasound?

OBJECTIVE: To demonstrate the significance of the double line appearance of the septi pellucidi laminae (SPL) on fetal ultrasound. METHOD: A total of 522 uncomplicated singleton pregnancies (15 to 39 weeks' gestational age) with fetal ultrasounds were enrolled. The presence of a single versus double line SP as well as measurement of the cavum septi pellucidi (CSP) was determined retrospectively. Ultrasound settings from the CSP images were recorded. Thickness of the SPL was measured in 20 ultrasound and 14 MRI cases; histology was reviewed from one neonate. Maternal BMI and gestational age were also recorded. RESULTS: The presence of double line SPL is a normal sonographic finding, seen in 47% (188/403) of normal fetuses. Thickness of the SPL in 10 cases with double line averaged 1.4 mm and in 10 cases with single line averaged 0.8 mm; MRI measurements were within 0.1 mm of the corresponding ultrasound measurements. Double line cavum was more often seen with mid-dynamic contrast range settings (5, 6) rather than high range settings (7-10) (P value <.05). The double line was only visualized on ultrasound when the angle of insonation was at or near perpendicular to the laminae; it was never visualized on coronal ultrasound imaging or MRI imaging. CONCLUSION: A double line septum pellucidum lamina is a normal finding seen in almost 50% of uncomplicated singleton pregnancies. It may be attributed to borders of cell layers within each lamina that form separate specular reflections on both sides; this can be accentuated by ultrasound settings and beam angulation.

Cavum septum pellucidum nomogram during the second trimester of pregnancy.

This study aimed to determine cavum septum pellucidum (CSP) nomogram values between 15-28 weeks of gestation. Routine biometric measurements and CSP width were measured by transabdominal ultrasonography in 6042 structurally normal foetuses between 15-28 weeks of gestation. Distribution of CSP width by the week of pregnancy and percentile values were calculated. The mean week of gestation (GW) was 21 ± 1.7, and the mean biparietal diameter (BPD) was 50.2 ± 5.8 mm. The CSP width range was 1.6-7.7 mm at 15-28 weeks, and the mean CSP width was 4.1 ± 0.8 mm. CSP width was found to have a significant correlation between a gestational week (CSP = GW X 0.2705-1.6121; R = 0.62; p < .01) and BPD (CSP = BPD X 0.0859-0.273; R = 0.651; p 0.01). CSP width was found to differ significantly according to gestational weeks, and percentile distributions were calculated. Between 15 and 28 weeks of gestation, the 95th percentile values of CSP width were found to be 3.7-7 mm. Our study was determined that CSP width increased linearly between 15-28 weeks of gestation. For this reason, we think that it would be more appropriate to use CSP width percentile values in the examination of the foetus. Impact statementWhat is already known on this subject? The cavum septum pellucidum can be easily identified and evaluated by ultrasonography after 18 weeks of pregnancy. CSP can be associated with severe brain anomalies if it is not visualised or deformed. Moreover; large CSP may be associated with chromosomal abnormalities.What do the results of this study add? Our study showed that CSP width increased linearly between 15-28 weeks of gestation. CSP width was found to differ significantly according to gestational weeks, and between 15 and 28 weeks of gestation, the 95th percentile values of CSP width were found to be 3.7-7 mm.What are the implications of these findings for clinical practice and/or further research? We reported that it would be more appropriate to use CSP percentile values according to the gestational week in the definition of abnormal CSP.

Surgical management of symptomatic cavum septum pellucidum cysts: systematic review of the literature.

Cavum septum pellucidum (CSP) and cavum vergae (CV) cysts are commonly found incidentally. They are usually asymptomatic but may present with symptoms related to obstructive hydrocephalus. There is no consensus about the management of symptomatic CSP and CV cysts. We present, to the best of our knowledge, the first systematic review of the different treatment options for symptomatic CSP and CV cysts. We conducted a literature review using PubMed database, searching for cases of symptomatic CSP and CV cysts managed surgically, and published until April 2019. Preoperative characteristics, surgical procedure, and postoperative outcome were analyzed using SPSS® software (Statistical Package for Social Sciences, IBM®). We found 54 cases of symptomatic CSP and CV cysts managed surgically (34 males, 20 females, 1.7/1 male to female ratio). Mean age was 24.3 ± 20.1 years. The most common presentation was headaches (34 patients, 62%), followed by psychiatric symptoms (27 patients, 49.1%). Preoperative radiological hydrocephalus was present in 30 patients (54.5%). The most common surgical procedure was endoscopic fenestration (39 patients, 70.9%), followed by shunting (10 patients, 18.2%), open surgery (3 patients, 5.5%), and stereotactic fenestration (1 patient, 1.8%). Complete resolution of symptoms was achieved in 36 patients (65.5%) and partial resolution in 7 patients (12.7%), and symptoms were unchanged in 2 patients. The present review suggests that surgical treatment could provide resolution of the symptoms in most of the cases, regardless of the procedure performed. Although mean follow-up was short among the studies, recurrence rate was low.

Bilateral subependymal pseudocysts as a pitfall in diagnosis of absence of the cavum septum pellucidum.

Absent cavum septum pellucidum in the fetus is a common condition that may be associated with a variety of associated abnormalities. Herein, we present a case to emphasize a new pitfall in the differential diagnosis of the absence of the cavum septum pellucidum (CSP). Prenatal ultrasound views were concerning for partially absent CSP in the third trimester and subependymal pseudocysts (SEC) after a normal CSP visualization in the second trimester. The postnatal MRI demonstrated a normal corpus callosum, normal gyration, normal opthalmic nerves, and isolated SEC blocking the views of cavum septum pellucidum.

The Prevalence of Cavum Septum Pellucidum in Mental Disorders Revealed by MRI: A Meta-Analysis.

OBJECTIVE: The prevalence of cavum septum pellucidum (CSP) in mental disorders, particularly schizophrenia spectrum disorders and mood disorders, remains uncertain. The authors used a meta-analytical approach to determine the prevalence of CSP in mental disorders and to compare these with the prevalence of CSP in psychiatrically healthy comparison subjects. METHODS: PubMed and Embase were systematically searched for relevant articles published as of January 9, 2018. After a quality assessment of individual studies using the Newcastle-Ottawa Scale, a random-effects model within Stata statistical software was used to synthesize 25 eligible studies that included 2,392 patients with mental disorders and 1,445 psychiatrically healthy comparison subjects. RESULTS: The prevalence of CSP of any size and large CSP was found to be significantly higher in individuals with mental disorders compared with healthy comparison subjects, and the prevalence of CSP in schizophrenia spectrum and mood disorders did not differ between the groups. CONCLUSIONS: The meta-regression with predefined covariance indicated that imaging parameters were not associated with the heterogeneity among original studies; however, the mean age of enrolled subjects was identified as a possible source of heterogeneity. No publication bias was found.

Utility of indirect sonographic signs (including cavum septum pellucidum ratio) in midgestational screening for partial agenesis of corpus callosum.

PURPOSE: This study was undertaken to evaluate the performance of indirect sonographic signs in detecting partial agenesis of the corpus callosum (pACC) at midgestation, focusing on the cavum septum pellucidum (CSP) ratio. METHODS: A retrospective case-controlled study of singleton pregnancies was conducted, examining fetuses diagnosed with isolated pACC and normal controls. At midgestational age, fetal head volumes were imaged with 3D US and stored for the evaluation of indirect sonographic findings in axial planes. RESULTS: Fifteen normal and 15 abnormal fetuses (with pACC) were analyzed. Based on a CSP ratio < 1.5, detection of pACC increased from 66.7% (10/15) to 80% (12/15). All indirect signs proved highly suspicious for pACC (risk ratios > 1). CONCLUSION: Use of indirect sonographic signs to screen for pACC at midgestation is challenging. However, a low CSP ratio may improve the detection rate, serving as a new indirect sign.

Transitory cystic cavities in the developing mammalian brain - normal or anomalous?

Transitory cavities associated with the ventricular system represent probably one of the most unique features in the developing mammalian brain. In rodents, the cavities exist transiently in the developing brain and do not appear to be associated with any pathological events. Among the various cavities, the pyramidal-shaped cavum septum pellucidum (CSP) located beneath the corpus callosum and between the lateral ventricles is most well defined. In addition to the CSP are the bilateral subependymal cysts that are consistently associated with the third and fourth ventricles as well as the aqueduct. The cavities/cysts contain a large number of amoeboid microglia expressing surface receptors and hydrolytic enzymes common to tissue macrophages. The significance of these cavities in the developing brain remains a conjecture. Firstly, the cavity walls are free of an apparent epithelial lining; hence, it is speculated that the cavities that appear to communicate with the widened neighboring interstitial tissue spaces may have resulted from physical traction due to the rapid growth of the perinatal brain. Secondly, the cavities contain prominent clusters of amoeboid microglia that may be involved in clearing the debris of degenerating axons and cells resulting from the early brain tissue remodeling. With the increase in brain tissue compactness following the beginning of myelination in the second postnatal week, all cavities are obliterated; concomitantly, the number of amoeboid microglia in them diminishes and all this might signal further maturation of the brain.

An Analysis of Outcome of Endoscopic Fenestration of Cavum Septum Pellucidum Cyst - More Grey than Black and White?

BACKGROUND: Cavum septum pellucidum (CSP) and cavum vergae are actually fluid-filled, generally communicating midline cavities located between the third ventricle and corpus callosum. There have been various reports of their association with many behavioral and psychiatric disorders. Infrequently, they have been associated with an obstructive hydrocephalus-like picture. Although the structure and management of CSP has long been known, it has been an enigma as far as functional significance and management indications are concerned. The authors of this article try to analyze the significance of a persistent cavum and involvement of the same entity in varied presentations ranging from an incidental imaging finding to acute hydrocephalus, and propose a possible implication on the present surgical intervention paradigm. PURPOSE: To assess the surgical outcome of fenestration of a CSP cyst. METHODS: Retrospective analysis of 3 patients who underwent endoscopic fenestration for CSP with obstructive hydrocephalus between 2012 and 2014 was done, and data were analyzed for symptomatic clinical improvement in particular behavior. RESULTS: Pre- and postoperative brain MRI showed a significant decrease in the size of the cyst as well as the ventricles. There were no recurrences during follow-up. All of the patients improved. CONCLUSIONS: (1) Endoscopic fenestration of symptomatic CSP cysts is a safe treatment option. (2) Neurocognitive assessment is essential in the evaluation and outcome assessment of CSP.

Cavum septi pellucidi cysts: a survey about clinical indications and surgical management strategies.

INTRODUCTION: Cavum septi pellucidi (CSP) cysts have a very low incidence (0.04%). Symptomatic patients usually present aspecific symptoms. For this reason, the management of these patients is still debated. MATERIALS AND METHODS: We selected the case of a ten year old patient, with a clinical history of frontal morning headaches and difficulty in concentration. Brain MRI documented a septum pellucidum cyst and a moderate biventricular dilation. We submitted the case, and a questionnaire concerning indications to surgery and management options to an international group of 54 pediatric neurosurgeons, analyzing the results and comparing them with the current literature. RESULTS: The majority of the participants (50%) indicated as appropriate at the early stage only a clinical observation. In case of persistence of clinical symptoms, 58% opted for intracranial pressure (ICP) monitoring, which, if raised, was considered by 91% as an adequate indication to proceed with surgical treatment. A total of 98% of the participants indicated endoscopic fenestration of the cyst as the preferred surgical strategy. CONCLUSIONS: The management of symptomatic patients with CSP cyst is controversial. Our results suggest that in most of the patients with aspecific symptoms, clinical observation and eventually ICP monitoring are adequate to identify patients for surgery.

The anterior complex: A visual mnemonic to aid in identification of normal structures.

The anterior complex of the fetal brain is a group of structures that are important to evaluate during the routine anatomic survey to exclude several serious brain malformations. These structures include the cavum septum pellucidum, anterior horns, interhemispheric fissure, callosal sulcus, and corpus callosum. The relationship between these structures is easily remembered with the presented visual cartoon. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:477-479, 2017.

Symptomatic Cavum Vergae Cyst in a Geriatric Patient: A Report of a Rare Case and Conservative Management Approach.

Cavum vergae (CV) cysts constitute a small proportion of intracranial cysts, and although generally asymptomatic, there are occasional cases where they might exhibit clinical manifestations. We present a clinical case of a 79-year-old female patient who had a clinical manifestation of headache on the occipital side of the head with irradiation to the shoulder girdle as well as numbness, dizziness, visual impairment, sleep disturbances, and tingling in the hands for three months. Vertigo and rightward staggering had been experienced for two weeks. On physical examination, it was discovered that there was smoothed physiological lordosis, restricted and painful movements, and paravertebral muscle rigidity in the cervical region. The patient had bilaterally reduced biceps and triceps reflexes, painful Erb's points, and hypesthesia over the C5 and C6 dermatomes on the right side. The patient had decreased coordination and displayed staggered movement to the right. A CT scan discovered dilated subarachnoid spaces of the convexity and a CV cyst. The patient was prescribed conservative therapy consisting of etoricoxib oral at a dosage of 2 × 60 mg for seven days, tolperisone hydrochloride orally at a dosage of 2 × 150 mg for seven days, pregabalin 75 mg, one pill in the evening for seven days, ozoid (a gel containing ozone) for external application, and vinpocetine 2 × 10 mg orally for two months. Following the conservative treatment, the patient exhibited improvement in her symptoms and no longer had challenges carrying out her daily tasks. Furthermore, six months after the therapy, the patient did not experience any symptoms. Long-term follow-up will be conducted in cases of symptom recurrence or cyst enlargement.

Genesis of Mental Disorders: Could It Be Cavum Septum Pellucidum (CSP) et Vergae? A Case Report of CSP in Schizophrenia with Catatonia.

In our case report, a 29-year-old male patient with a known history of schizophrenia presented with altered mental status and catatonia and was found to have an enlarged (21mm) cavum septum pellucidum (CSP) on magnetic resonance imaging (MRI). He was subsequently treated with escitalopram, olanzapine, methylphenidate, lorazepam, and eight electroconvulsive therapy (ECT) treatments during his hospital course, after which his catatonia improved. We compared this to other cases in which a large CSP was identified and discussed the possibility of increased susceptibility to psychosis, specifically catatonia, which might be associated with this developmental anomaly.

Sonographic appearance of the cavum septum pellucidum et vergae in normal fetuses in the second and third trimesters of pregnancy.

BACKGROUND: To characterize the cavum septum pellucidum et vergae (CSPV) in normal fetuses in the second to third trimester. METHODS: The cavum septum pellucidum (CSP) and CSPV were investigated in 322 uncomplicated singleton pregnancies from 25 to 39 weeks' gestation. Visualization rate, width, and morphology of both CSP and cavum vergae (CV) were assessed by ultrasound and MRI. RESULTS: The CSP and CSPV visualization rates were 100% and 7.8% (25/322), respectively. The mean widths were 6.3 ± 1.2 mm (3.4-10 mm) and 6.7 ± 1.0 mm (5.1-9 mm), respectively, with no significant correlation between width and gestational age (r = -0.108, p > 0.05 and r = -0.182, p > 0.05, respectively). In CSPV fetuses, the CV to CSP ratio was 1.004 ± 0.018 (0.967-1.033). All CSPVs were rectangular in the transverse plane and extended posteriorly beyond the midpoint of the brain. CONCLUSIONS: Common features of CSPVs include (1) a rectangular morphology, (2) communication between the two cavities, (3) a CV width within the normal range for CSP, and (4) a CV-CSP ratio of 1. These findings may help distinguish normal from abnormal CSPV.

A method framework of automatic localization and quantitative segmentation for the cavum septum pellucidum complex and the cerebellar vermis in fetal brain ultrasound images.

Background: Early detection of central nervous system (CNS) anomalies in human embryos through prenatal screening is crucial for timely intervention and improved patient outcomes. Fetal brain mid-sagittal ultrasound images (FBMUIs) play a pivotal role as a diagnostic tool for detecting structural abnormalities. However, the automatic localization and quantitative segmentation of complex anatomical structures such as the corpus callosum-cavum septum pellucidum complex (CCC) and cerebellar vermis (CV) in FBMUIs present significant challenges. Methods: To address this issue, we propose an integrated framework that combines anatomical knowledge with computer vision techniques. Our framework comprises four steps: (I) generation of average templates for CCC and CV local images using a variational autoencoder (VAE); (II) localizing the CCC by using the "Initial Localization-Accurate Localization-Result Detection" strategy, followed by segmenting it based on morphological characteristics using the "Initial Contour Fitting-Contour Iteration" strategy; (III) applying a similar strategy as CCC localization and CV segmentation; and (IV) leveraging spatial and morphological characteristics to achieve accurate localization and segmentation. Results: Our CCC and CV localization and segmentation methods were validated by using 140 FBMUIs from various perspectives. The accuracy and effectiveness of our approach were demonstrated through data statistics and comparative analysis. Currently, clinical trials are being conducted on our method at Shengjing Hospital of China Medical University. Conclusions: Our proposed integrated framework presents a novel solution for the automatic localization and quantitative segmentation of the CCC and CV in FBMUIs. It shows promise for early diagnosis of CNS anomalies in human embryos, offering significant clinical implications.

Examining for Cavum Septum Pellucidum and Ventricular Enlargement in Retired Elite-Level Rugby League Players.

Objective: A cavum septum pellucidum (CSP) has been reported as a visible brain anomaly in normal individuals as well in some former combat and collision sport athletes. The appearance of CSP with fenestrations and ventricular enlargement are considered associated features of the neuropathological diagnosis of chronic traumatic encephalopathy. The current study examined CSP anatomic features and lateral ventricle size in retired elite rugby league players and controls. Methods: Forty-one retired rugby league players and 41 healthy community controls, similar in age and education, underwent structural MRI scans. CSP grade, CSP length, corpus callosum septal length, and Evans' ratio (for lateral ventricle size) were rated by two of the current study authors. All participants also self-reported concussion exposure histories, depressive symptoms, daytime sleepiness, and impulsivity. They completed a neuropsychological test battery assessing premorbid intellectual functioning, attention, processing speed, language, visuospatial skills, memory, and aspects of executive functioning. Results: The two raters had high agreement for CSP grade (Cohen's κ = 0.80), CSP length [intraclass correlation (ICC) = 0.99], corpus callosum septal length (ICC = 0.73), the CSP/septal ratio (ICC = 0.99), and the Evans' ratio (ICC = 0.75). Twenty-five retired players (61.0%) had an abnormal CSP compared to 17 controls [41.5%; χ ( 1 ,   82 ) 2 = 3.12, p = 0.08, odds ratio = 2.21]. The CSP/septal ratio was larger for retired players than for the controls. The Evans' ratio did not differ between the two groups. In the retired rugby league players (n = 41), those with normal (n = 16) and abnormal (n = 25) CSP grades did not differ across age, age of first exposure to collision sport, years of sport exposure, concussion history, or 23 clinical and cognitive variables. Conclusion: This study revealed a difference in the size of the CSP between retired professional rugby league players and controls. There was no significant difference in the size of the ventricles between the two groups. There were no significant differences between those with vs. without an abnormal CSP on age of first exposure to rugby league, years of exposure to repetitive neurotrauma, number of lifetime concussions, depression, impulsivity, perceived cognitive decline, or on any neuropsychological test.

Unusual vascular anatomical variant leads to spontaneous hemorrhage in a cavum septum pellucidum in an adolescent: A case report and literature review.

Background: Hemorrhagic lesions of the septum pellucidum are rare and usually occur in neonates. They can be due to a number of etiologies. Here, we report a rare case of adolescent nontraumatic septum pellucidum hemorrhage with a review of literature. Case Description: A 16-year-old girl presented with a 1-month history of gradual visual deterioration in the left eye, intermittent headache, and vomiting. Brain imaging showed hematoma located between the leaflets of the septum pellucidum with obstructive hydrocephalus. Transcallosal resection of interventricular mass was done. The patient was discharged with improved neurological symptoms; however, the left eye vision did not recover. Imaging demonstrated a unique anatomical variant in deep vascular structures. Conclusion: Cavum septum pellucidum hemorrhage is rare in adults. Many theories were constructed to explain its etiology. Bleeding due a vascular anatomical variant was not previously encountered. Understanding the embryological origin and anatomical details are important for proper clinical assessment and management of these patients.

Cavum septum pellucidum and vergae cyst: A symptomatic case with intracranial hypertension and multiple nerve involvement.

Background: Cavum septum pellucidum (CSP) and cavum vergae (CV) are normal anatomical variations present in some children, adolescents, and adults. When the cavity is larger than normal, it is called a cyst. Symptomatic cases of CSP and CV cyst are rare, and the clinical presentation is varied. A case with multiple nerve involvement is described. Case Description: A healthy 17-year-old female presented a sudden headache, right cervicobrachialgia, right ptosis, visual changes, and left facial paralysis over 10 days. Head magnetic resonance imaging revealed CSP and CV cyst. Inflammation, infection, and vascular disorders were ruled out. We decided to perform a right transfrontal endoscopic intraventricular septostomy and a right Monro foraminoplasty, which were successful. One month after surgery, the patient had no more signs or symptoms. She has remained asymptomatic for the past year. Conclusion: Multiple nerve involvement was directly related to CSP and CV cyst. The cyst bilaterally occluded the foramen of Monro causing intracranial hypertension. It was possible to obtain complete resolution of the clinical features through neuroendoscopic fenestration and foraminoplasty.

Utility of Measuring Fetal Cavum Septum Pellucidum (CSP) Width During Routine Obstetrical Ultrasound for Improving Diagnosis of 22q11.2 Deletion Syndrome: A Case-Control Study.

Objective: To evaluate the utility of measuring fetal cavum septum pellucidum (CSP) width during routine, mid-pregnancy ultrasound for improving diagnosis of 22q11.2 deletion syndrome amongst fetuses with and without conotruncal anomalies. Patients and Methods: This was a retrospective case-control study (2005-2016). Fetuses and newborns with 22q11.2 deletion and/or conotruncal cardiac anomalies were identified using a regional, clinical database. A control group was assembled in a 2:1 ratio to create three groups for comparison: i) 22q11.2 deletion syndrome; ii) isolated conotruncal anomalies; and iii) controls. Eligibility was restricted to those with stored ultrasound images between 18-22 weeks' gestation and a minimum biparietal diameter of 40 mm. Post-processing measurement of CSP width was performed in a standardized fashion by two blinded and independent study personnel. Descriptive and inferential statistics, regression modeling, and receiver operator curves (ROC) were used to compare outcomes between groups and evaluate sensitivity/specificity of CSP width as a marker of 22q11.2 deletion syndrome. Results: Twenty-nine cases of 22q11.2 deletion and 64 cases of isolated conotruncal anomalies were matched to 186 healthy controls. Cases with 22q11.2 deletion syndrome had significantly larger CSP widths (5.36 mm; SD=1.2) compared to those with isolated conotruncal anomalies (3.75 mm; SD=1.11) and healthy controls (2.93 mm; SD=0.57; p<0.0001). There was no difference in CSP width amongst those with 22q11.2 deletion irrespective of the presence/absence of a conotruncal anomaly (p=0.362), or by type of conotruncal anomaly (p=0.211). Using a CSP width cutoff >4.3 mm, fetuses with 22q11.2 deletion can be accurately identified with good sensitivity (89.7%) and specificity (84%). Conclusion: Fetuses with 22q11.2 deletion syndrome have dilated CSPs when compared to those with isolated conotruncal anomalies or controls. Because CSP dilation can be evaluated during routine mid-pregnancy ultrasound using standard images of the fetal head, measurement could easily be incorporated to enhance prenatal diagnosis of this phenotypically diverse condition.