Percutaneous endoscopic recanalization of the catheter: a new technique of proximal shunt revision

OBJECTIVE

Proximal ventricular catheter obstruction by the choroid plexus is a frequent occurrence in children with shunted hydrocephalus. In some cases, the flow is obstructed owing to membranous occlusion by a small amount of tissue. It has been shown that only a few of the multiple catheter openings need be patent to maintain adequate shunt function. Recent advances in technology have improved our ability to perform intraluminal endoscopic catheter dissection and minimize the morbidity associated with shunt maintenance.

METHODS

Percutaneous endoscopic shunt recanalization was performed in 20 cases (18 children) under institutional review board study protocol. The mean age was 32 months, and all children had signs and symptoms of shunt malfunction, confirmed by computed tomography and magnetic resonance imaging and verified by shunt taps. Under aseptic conditions in the operating room, the Rickham reservoir was entered with a 16-gauge intravenous catheter, and the obstruction was visualized with a fiber endoscope (0.5-0.8 mm). Intraluminal dissection using electrocautery was performed with endoscopic guidance to visualize the catheter and flushing of the valve.

RESULTS

At a mean follow-up time of 20 months (range, 15-29 mo), the children are doing well, with computed tomographic and magnetic resonance imaging confirmation of adequate ventricular decompression in the 17 successful cases (85%). There were three failures in the study, necessitating a standard open shunt revision.

CONCLUSION

The percutaneous endoscopic shunt recanalization procedure can be used successfully to treat proximal shunt malfunction.

Coagulopathy with the use of hetastarch in the treatment of vasospasm

The use of colloid agents to achieve hypervolemia in the prevention and treatment of postsubarachnoid hemorrhage (post-SAH) vasospasm is included in the standard of care at many institutions. Risk profiles are necessary to ensure appropriate use of these agents. In a series of 85 patients with recent aneurysmal SAH, 26 developed clinical symptoms of vasospasm. Fourteen of the 26 were treated with hetastarch for volume expansion while the other 12 received plasma protein fraction (PPF). Clinically significant bleeding pathologies were noted in six patients who received hetastarch as a continuous intravenous infusion. Hetastarch increased partial thromboplastin time from a mean of 23.9 seconds to a mean of 33.1 seconds (p < 0.001) in all patients who received infusions of this agent, while no effect was noted in the 12 patients who received PPF infusions. No other coagulation parameters were altered. This study shows an increase in coagulopathy with the use of hetastarch as compared with the use of PPF for the treatment of postaneurysmal vasospasm.

Symptomatic lumbar stenosis following fusion using sublaminar hooks. Case report

A case of postfusion lumbar stenosis caused by the presence of sublaminar hooks is described. The patient was a 52-year-old man who 11 years previously had undergone lumbar fusion with Harrington rod instrumentation for a traumatic L-2 vertebral body fracture. Postoperatively, he developed progressive low-back pain, neurogenic claudication, and significant lower-extremity weakness and atrophy. Upon radiological examination, he was found to have high-grade lumbar stenosis at the level of the caudal sublaminar hooks. The instrumentation was removed and the area of radiological stenosis decompressed. Clinically, both the patient's pain and motor deficits resolved and, on postoperative imaging, the stenosis was relieved. Thus, despite other areas of persisting pathology, it is concluded that the stenosis occurring at the level of the caudal sublaminar hooks contributed to the patient's symptoms. Although not a common cause of postfusion stenosis, the presence of instrumentation in the proximity of neural elements must be considered as an etiology for neurological dysfunction.

Atlantooccipital subluxation in a neonate with Down's syndrome. Case report and review of the literature

Atlantooccipital subluxation (AOS) occurs in up to 63% of patients with Down's syndrome. However, presenting symptoms and the age at which preoperative screening becomes necessary have not been clearly delineated. Recently, a 16-day-old female with Down's syndrome and AOS presented to our institution. Following patent ductus arteriosus ligation, her neurological examination revealed trace movement, few spontaneous respirations, and left lower extremity clonus. Cervical spine radiographs revealed significant AOS. She was reduced and underwent a fusion from the occiput to C2. She gradually regained full strength and sensation. This case is the youngest example of AOS related to Down's syndrome described. It emphasizes the need for preoperative screening of all patients with Down's syndrome.