Ultrasound-guided placement of ventricular catheters in first-time pediatric VP shunt surgery.

PURPOSE: Ventriculo-peritoneal (VP) shunts are effective for treatment of hydrocephalus in all age groups; however, they are associated with complications, a common one being ventricular catheter (VC) obstruction. VC position is likely to influence VC survival; however, most VCs are positioned freehand without guidance. This paper describes the accuracy of ultrasound guidance for VC placement and the impact of tip location on VC occlusion rate. METHODS: This is a retrospective cohort study of hydrocephalic children with first-time VP shunt and ultrasound-guided VC placement. Data recorded were age, sex, cause of hydrocephalus, side (left or right) and location (frontal or occipital) of VC, and exact postoperative position within the ventricle on first postoperative imaging: middle of ventricle (optimal position), near or touching the medial or lateral ventricle wall, within the third ventricle, and at the contralateral side. RESULTS: Of the 128 screened patients, 85 had a first postoperative imaging that clearly defined the VC position and were included. The follow-up was at least 12 months. Seventy-three percent of VCs were placed on the right and 71% via a frontal burhole. Eighty-three of 85 VC tips (95%) were in the intended ventricle, 61% at optimal position. Nine of 85 VCs (10%) obstructed within the first 12 months. Seven of nine (78%) obstructed VCs were located in a nonoptimal position (p = 0.016). Two of nine (22%) obstructed VCs entered through a frontal and seven of nine (78%) through an occipital burrhole (p = 0.016). CONCLUSION: Ultrasound-guided VC placement is as precise as frameless navigated placement. The optimal VC position was associated to a significant lower VC obstruction rate. The frontal position was superior to the occipital. Intraoperative US guidance is fast with almost no extra time and no extra cost. US-guided VC placement should become standard of care in VP shunt surgery.

Enlargement of an incidental internal carotid artery aneurysm embedded in pituitary adenoma associated with medical shrinkage of the tumor: Case report.

BACKGROUND: Currently, transsphenoidal surgery (TSS) is the preferred method for surgical treatment of intrasellar pituitary adenomas. However, it carries some risk of intraoperative arterial injuries, which is mainly attributed to direct iatrogenic rupture of the internal carotid artery (ICA). There is anecdotal evidence suggesting that intracranial aneurysms are coincidentally found significantly more frequently in the setting of pituitary adenomas than when the incidence is compared to other intracranial neoplasms. The exact cause of this discrepancy remains unclear, but it certainly raises concerns about the potential existence of an ICA aneurysm, which might be encountered during TSS and in some cases may cause hemorrhagic complications. CASE DESCRIPTION: We present a case of a patient who was found to have a growth hormone (GH)-secreting pituitary adenoma and a coexisting cavernous ICA aneurysm which was embedded within the tumor. The patient underwent medical treatment of the adenoma. However, shrinkage of the tumor was associated with enlargement of the observed aneurysm, warranting endovascular intervention. CONCLUSIONS: This case report is an illustration for physicians to be conscientious about the potential danger posed by the coexistence of an intratumoral aneurysm in the setting of a pituitary adenoma. Special attention should be given to recognition of an intrinsic flow void signal on the presurgical imaging of the tumor, and if observed, magnetic resonance angiography (MRA) should be performed for preoperative planning. If MRA is not performed routinely, detailed review of high-resolution magnetic resonance imaging is recommended to detect any flow artifacts suggestive of an aneurysm.