Absent septum pellucidum
Updates to Article Attributes
An absent septum pellucidum may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions.
Epidemiology
The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population.
Pathology
An absent septum pellucidum may be developmental or acquired secondary to another pathological process 1,2.
Cavum septum pellucidum is always visualizedvisualised between 18 and 37 weeks and within a biparietal diameter of 44 to 88 mm. Failure to detect the cavum septum pellucidum within this time interval requires further investigation; however the absence of cavum septum pellucidum on the ultrasound exam prior to 18 weeks, or later than 37 weeks, is considered a normal finding
Developmental
Acquired
- aqueductal stenosis causing congenital hydrocephalus
- Chiari II malformation causing congenital hydrocephalus
- hydranencephaly
- porencephaly
Radiographic features
Besides the non-visualisation of the septum pellucidum the following characteristics may be seen 3:
- boxing/squaring off of the frontal horns
- inferior pointing frontal horns
- abnormally inferiorly positioned fornix (coronal views)
-<p>An <strong>absent septum pellucidum</strong> may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions.</p><h4>Epidemiology</h4><p>The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population. </p><h4>Pathology</h4><p>An absent septum pellucidum may be developmental or acquired secondary to another pathological process <sup>1,2</sup>. </p><p><a title="Cavum septum pellucidum (CSP)" href="/articles/cavum-septum-pellucidum-1">Cavum septum pellucidum</a> is always visualized between 18 and 37 weeks and within a biparietal diameter of 44 to 88 mm. Failure to detect the cavum septum pellucidum within this time interval requires further investigation; however the absence of cavum septum pellucidum on the ultrasound exam prior to 18 weeks, or later than 37 weeks, is considered a normal finding </p><h5>Developmental</h5><ul>- +<p>An <strong>absent septum pellucidum</strong> may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions.</p><h4>Epidemiology</h4><p>The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population. </p><h4>Pathology</h4><p>An absent septum pellucidum may be developmental or acquired secondary to another pathological process <sup>1,2</sup>. </p><p><a href="/articles/cavum-septi-pellucidi">Cavum septum pellucidum</a> is always visualised between 18 and 37 weeks and within a biparietal diameter of 44 to 88 mm. Failure to detect the cavum septum pellucidum within this time interval requires further investigation; however the absence of cavum septum pellucidum on the ultrasound exam prior to 18 weeks, or later than 37 weeks, is considered a normal finding</p><h5>Developmental</h5><ul>