Management of Aneurysms and Vascular Malformations During Pregnancy and Puerperium

Neurosurgical Procedures During Pregnancy

To determine recommendations for proper management of aneurysms and vascular malformations, we reviewed the literature of women during pregnancy and puerperium who were candidates for neurosurgical intervention.

In a single institutional retrospective study by Nossek et al., the records of 34 pregnant or early postpartum women who were candidates for neurosurgery were analyzed. Of those 34 women, 5 had vascular malformations categorized as cavernous malformation (CM) ( n = 3), moyamoya disease ( n = 1), and arteriovenous malformation (AVM) ( n = 1) . Of the three patients with CM, one underwent a craniotomy and two were conservatively managed. One of the conservatively managed women developed diplopia. All three women delivered healthy babies at term with no obstetric complications. The woman with moyamoya disease presented hemorrhagically, and suffered a spontaneous abortion at 22 weeks. The woman with the AVM presented with an intracranial hemorrhage due to rupture and underwent endovascular embolization. She delivered at 36 weeks of gestation with no obstetric complications.

In the same study by Nossek et al., of the 16 women who underwent neurosurgery during pregnancy, 7 had no neurosurgical or obstetric complications, 5 had neurosurgical complications but all resolved, and 4 patients had preterm delivery with 3 out of 5 babies with Apgar scores less than 7 but had a favorable outcome. From the total series of 34, 12 patients delayed their surgery. Of the five patients who delayed their surgery until later in pregnancy, four developed neurosurgical complications. Of the seven patients who delayed their surgery until after delivery, four patients experienced complications: three with neurosurgical complications and one with obstetrical complications. This case series highlights the risks of delaying treatment in neurosurgical patients and the favorable outcomes when treatment was implemented in a timely fashion.

In a study by Cohen-Gadol et al., 19 of 34 patients who were candidates for neurosurgery underwent neurosurgical intervention during pregnancy. Twelve patients presented with vascular malformations including aneurysm ( n = 5), AVM ( n = 5), dAVF ( n = 1), CM ( n = 1). Of these 12 patients, clinical presentation included subarachnoid hemorrhage ( n = 5), intracerebral hemorrhage ( n = 3), and intraventricular hemorrhage ( n = 1). Six patients underwent immediate surgery for aneurysm clipping ( n = 3), AVM resection ( n = 2), and CM resection ( n = 1) after the patient rebled 1 week after initial presentation. Of the six other patients with cerebrovascular lesions, two patients (PICA aneurysm and AVM) underwent a Cesarean section and were conservatively managed, one patient received an urgent Cesarean section then aneurysm repair, one patient with dAVF underwent a therapeutic abortion followed by radiosurgery, one patient with an AVM was conservatively managed with radiosurgery delayed until after delivery, and one patient with an AVM underwent embolization complicated by a thalamic stroke. There was no fetal or maternal mortality or permanent morbidity associated with surgery. Overall, this study demonstrates the relative safety of neurosurgical intervention during pregnancy.

Radiation Exposure

The risks associated with radiation in diagnostic procedures should be considered when developing a neurosurgical treatment plan. The International Commission on Radiological Protection issued guidelines and summary recommendations for the use of medical radiation during pregnancy. The consequences of radiation differ among the stages of pregnancy, with the fetus most vulnerable to the effects of radiation during organogenesis weeks 3–8 of gestation and the early fetal period with central nervous system development weeks 8–25 of gestation . Radiation absorbed by the fetus above the threshold of 100–200 mGy places the fetus at risk for death, nervous system abnormalities, growth retardation or malformation, and childhood cancer .

The most commonly used diagnostic imaging modalities in neurosurgery, including head CTs, plain X-rays, and cerebral angiograms expose the fetus to far less than 50 mGy of radiation if the abdomen is shielded . During cerebral angiography, shielding the abdomen with lead results in exposure to the fetus of less than 1 mGy . Therefore, according to the International Commission of Radiological Protection, the risk to the fetus of death, nervous system abnormalities, and growth retardation or malformation would be negligible since the neurosurgical diagnostic modalities have levels of fetal radiation absorption below the 100–200 mGy threshold .