The Fate of the Arachnoid Villi in Humans

Villi arachnoidales undergoes in the course of life changes in relation to the skull bones and sinuses. Our aim was to determine the relations of the villi arachnoidales to the skull bone and/or sinuses from the neonatal period to adults. The investigations were performed on collection of 50 disarticulated macerated skull bones from the newborn to 30 years of age and on 20 skulls from individuals in the life period from 30 to 80 years of age. Villi arachnoidales produced imprints on the skull bones in the shape of holes and/or furrows corresponding to different shape of the villi arachnoidales. These imprints appeared very early in the period when the bony sprouts of the large skull bones received a thin covering of compact bone, the future lamina vitrea. At that time villi arachnoidales had no connection with the dural sinuses but with the diploe and with the diploic veins. By agglomeration of the villi in larger and large formations, granula meningea, Pacchionian granulations, the contact to sinuses was realized by means of short channels. The structural changes of villi arachnoidales may produce thrombophlebitis and hydrocephalus externus, especially in children. The fate and the relations of the villi arachnoidales are therefore of great importance for neurologist, neurosurgeon and otorhinolaryngologist

Spontaneous Isolated Dissection of the Abdominal Aorta

Isolated spontaneous dissection of the abdominal aorta is such a rare entity and there are only a few cases reported in literature up to date. A 42-year old male was admitted to the hospital with mild pain in the lower abdomen and back that had began seven days prior to admission together with the sudden onset of the ischemic symptoms of the left leg (ischemic ulcers of the calf, gangrenous toe and pallor foot). Patient denied any trauma, hypertension history was negative, while he was active cigarette smoker. MSCT and digital subtracted angiography have shown a dissection of the abdominal aorta approximately two centimeters below the origin of the inferior mesenteric artery extending in the left common iliac artery, with no sign of the aneurysmatic dilatation of the abdominal aorta. Emergent surgery was performed with aorto- biiliacal bypass graft interposition, amputation of the left toe and necrectomy of the left calf. Postoperative follow up and local vascular condition were satisfied. Even though is rare entity, isolated abdominal aorta dissection accounts for ap proximately 2–4% of all aortic dissection. Nowadays therapeutic regimen includes endovascular, open surgery or conser vative treatment

Low-dose Computed Tomography in a Pregnant Woman with a Ruptured Pseudoaneurysm of the Abdominal Aorta

Imaging the pregnant patient presents a unique challenge to radiologist due to the risk of radiation to the conceptus (embryo/fetus). A rare case of a successfully recognized and treated pseudoaneurysm (PA) of the abdominal aorta is to be presented. The pseudoaneurysm occurred in the third trimester and had a favorable outcome for the mother and the baby. Emergent abdominal ultrasound (US) is the first modality in diagnostic algorithm for the rupture of aortic aneurysm in a pregnant woman. It provides the most rapid diagnostic information, although intestinal gas and abdominal tenderness may limit its accuracy. To confirm the findings, magnetic resonance angiography (MRA) or CT angiography (CTA) can be used. In our case, the diagnosis was established using a color Doppler ultrasonography of the abdomen and was later confirmed by a low dose CT scan of the abdominal aorta. MRA in such cases have some disadvantages. At many health centers, the monitoring of patients with acute ruptures is more difficult in the MR suite than at the CT scanner. MRA angiographic images are also subject to degradation by multiple artifacts, and the visualization of the distal vasculature is suboptimal and inferior to the one done by CTA. Due to fetal movements, a small quantity of fresh blood can be overlooked by MR. MRA is often not available on a 24-hours basis, and the time required for making a diagnosis can preclude the use of MRA in an unstable patient. For this reason, we used a low dose CTA protocol to confirm the diagnosis. Low dose scanning protocols in CT can obtain sufficient diagnostic information while reducing the risk of radiation. A particular focus is put on the outline of new concepts for dose management and optimization. We used new approaches based on tube current modulation. The birth was induced by an urgent Caesarean section followed by a resection of a pseudoaneurysm and a reconstruction of the aorta with an end-to- end vascular prosthesi