Foramen ovale changes in growth-restricted fetuses.

OBJECTIVE: In animal experiments hypoxemia induces an increased shunting through the fetal foramen ovale (FO). Based on the hypothesis that the FO is expanded to permit more flow, the aim of this study was to determine the size of the FO in growth-restricted human fetuses. METHODS: Thirty-one women with singleton pregnancies complicated with growth-restriction (< 5th percentile) were examined at 24-39 weeks of gestation. The diameter between the FO valve and the atrial septum was determined during maximum excursion in a horizontal transverse section of the fetal heart, and the transverse diameter of the right atrium (RA) was noted. The pulsatility index (PI) was determined in the umbilical artery (UA) and absent or reversed end-diastolic flow velocity was noted. The measurements were compared with a reference population using Z-scores. RESULTS: In comparison with normally grown fetuses, the growth-restricted fetuses had a normal RA size (P = 0.08) but a smaller FO (P = 0.002), particularly when expressed as a relative size by the ratio FO/RA (P < 0.0001). This effect on the FO and FO/RA was seen mainly at < 32 weeks of gestation (P = 0.003 and P < 0.0001, respectively), and was not significant later in pregnancy. There was a tendency towards a negative relationship between relative size of the FO (FO/RA) and progressive placental compromise (overall P < 0.0001). CONCLUSIONS: Growth-restricted fetuses maintain a normally grown heart (expressed by the RA diameter) but a reduced FO diameter. The effect is seen before 32 weeks and tends to be more marked in fetuses with pronounced hemodynamic compromise of the placenta. This supports the theory that FO shunting is impaired in severely premature fetuses with placental compromise.

[Cavernous dural fistulas: Importance of trans-ocular Doppler ultrasound in evaluating venous patency and therapeutic choices]. / Fistules durales caverneuses: intéret de l'écho-Doppler transoculaire dans l'évaluation de la perméabilité veineuse et le choix thérapeutique.

Transcranial Duplex scan is a relatively recent diagnostic tool with many unexplored clinical potentials. The authors insist on the role of transocular exploration, as a non-invasive substitute to angiography and discuss two patients with cavernous meningeal arteriovenous fistula, a benign but relatively uncommon disease. In the first patient, in whom symptoms recurred, Duplex scan was able to rule out thrombophlebitis and to show increased flow in the fistula, thus leading to proper treatment. In the second patient, the identification of a periorbital thrombophlebitis innocented the fistula and prompted anti-coagulation. We conclude that besides its diagnostic capabilities, Duplex scan may be helpful in selecting proper treatment and follow-up in specific neurovascular conditions.

[A rare cause of diplopia: a sinus cavernous dural fistula. A case report]. / Une cause rare de diplopie: la fistule durale du sinus caverneux. A propos d'un cas.

Dural fistulas of the cavernous sinus represent a relatively unknown etiology for diplopia. The authors report on a case where combination of MR and transcranial Doppler (especially transocular) helped in diagnostic and therapeutic approach. They propose a new algorithm for the management of diplopia.

[Capillarovenous angioma of the maxillary sinus. Apropos of a case with review of the literature]. / Angiome capillaro-veineux du sinus maxillaire. A propos d'un cas avec revue de la littérature.

We report the case of a 30-year-old woman who presented with swelling of the left cheek, related to a capillarovenous angioma (previously known as cavernous osseous hemangioma), located in the left maxillary sinus. The different imaging modalities, histologic appearance and evolution criteria are reported and discussed.

["Mirror" intracavernous aneurysms. Therapeutic dilemma apropos of a case with review of the literature]. / Anévrismes intra-caverneux "en miroir". Dilemme thérapeutique à propos d'un cas avec revue de la littérature.

"Mirror" cavernous aneurysms are exceptional; only 66 such cases having been published until mid-1996. We report on a 68-year-old woman who presented for left exophthalmos, diplopia and neuralgia. MR and angiography demonstrated a giant symptomatic aneurysm on the left side and an incidental small one on the right side. The patient was treated in two sessions: first, she had selective embolization of her right aneurysm; two weeks later, her left carotid artery was sacrificed with detachable balloons, after a well-tolerated occlusion test. This original and successful approach permitted to achieve a reasonable goal when considering the patient's age, operative morbidity, risk of future complications and final result. A review of the pathophysiology, clinical manifestations and therapeutic indications is presented and discussed.

[Modern imaging in cerebral vein angioma]. / L'imagerie moderne dans les angiomes veineux cérébraux.

Cerebral venous angiomas are vascular malformations of the brain which, before the advent of modern imaging, and in particular MRI, were thought to be rare. They have a specific angiographic aspect called "caput Meduse" as it corresponds to the description of a large draining vein to which converge numerous radial veins located in the white matter. These true vascular malformations have characteristic histological features making it possible to differentiate them from other vascular malformations, notably cavernomas. These lesions are less scanty than classically believed, being the most frequent malformations encountered in post-mortem examination series. The circumstances in which cerebral venous angiomas are discovered vary considerably, and haemorrhage can be the revealing sign. Some authors regard these malformations as "abnormalities" of white matter veins and not as pathological entities, since they derive from a change in development during embryogenesis, but this theory is not supported by any anatomical evidence. The same authors attribute the bleeding to an associated cavernoma. Whereas CT enables venous angiomas and possible associated cavernomas to be detected, only repeated MRI explorations performed after the finding of venous angioma and hemorrhage can permit, by analysis of signal changes, to confirm or invalidate the non-pathological theory of the venous malformation and its tendency to bleed. Apart from hemorrhages, since gadolinium is used MRI is the most reliable and least invasive means to diagnose angiomas and to detect associated occult angiographic malformations. For this reason, nowadays only hemorrhages require an angiography in search of an arteriovenous malformation demanding prompt treatment. Moreover, MRI makes it possible to detect angiographically occult malformations.

[Pericardial hydatid cysts. Value of magnetic resonance imaging. Apropos of a clinical case]. / Kystes hydatiques péricardiques. Intérêt de l'imagerie par résonance magnétique. A propos d'un cas clinique.

Cardiac hydatic cysts are rare and represent 0.5 to 2% of all hydatic cysts in humans [1, 2]. They are usually found in the left or right ventricle, and exceptionally in the interventricular septum. An exclusively pericardia hydatic cyst is excessively rare. The case reported here emphasizes: That this hydatid cyst of the pericardium remained asymptomatic until rupture. The role of echocardiography as a diagnostic tool. The superiority of MRI to CT Scan in the establishment of a precise preoperative diagnosis.

Intracranial extension of an idiopathic orbital inflammatory pseudotumor.

Idiopathic orbital inflammatory pseudotumor (IOIP) with endocranial extension is very unusual. The authors used CT and MR to diagnose IOIP and demonstrate the presence of intracranial extension of orbital and lacrimal gland lesions. While providing additional evidence of IOIP having intracranial extension, this case report emphasizes the need to include IOIP as a possible differential diagnosis when radiologic explorations reveal lesions extending from the orbit to intracranial structures.

Imaging in the exploration of lumbosacral plexus avulsion. Two cases.

In all cases of post-traumatic sensorimotor deficit in the lower limbs unexplained by another pathology, it is not unreasonable to suspect a nerve root avulsion. Whenever available, MRI seems to be the choice examination as it is not invasive and provides a three-dimensional exploration. On the basis of two new cases and a review of the literature, the authors discuss the value of various imaging methods in this pathology.

MRI anatomy of the acoustic-facial bundle in vivo.

In this study performed on 5 healthy volunteers the authors used oblique axial, coronal and sagittal MRI sections suitable to be anatomical configuration of the acoustic-facial bundle and were able to individualize the nerves forming this bundle throughout their course, with the sole exception of the intermediate nerve (VII2). They also analysed the relations of these nerves between themselves and with the other elements of the cerebellopontine angle. In addition, a proton-density sequence (SE, 6,000/30 ms) made it possible to differentiate in vivo between the grey matter and the white matter sufficiently to individualize the principal nuclei and tracts of the brain stem, and in particular the main vestibulo-cochlear central pathways.