Intramedullary placement of ventricular shunts: a review of using bone as a distal cerebrospinal absorption site in treating hydrocephalus

Successful Implantation of a Ventricular Shunt With Termination in the Iliac Bone in the Adult Patient With Obstructive Hydrocephalus

BACKGROUND AND IMPORTANCE

With the exception of the 3 classic shunt placement options (ventriculoperitoneal, ventriculopleural, and ventriculoatrial), surgically feasible alternative sites for distal catheter placement remain limited and often require the assistance of an access surgeon. Tubbs et al suggested the possibility of intraosseous cerebrospinal fluid diversion in the ilium, noting that ilium infusion in cadaveric specimens was possible without the development of body edema or fluid overflow. Since this publication, limited case reports have been published on the success of ventriculo-ilium (VI) shunt placement. Here, we describe the technique used for successful VI shunt placement in 2 adult patients.

CLINICAL PRESENTATION

Here, we describe 2 patients with differing etiologies of hydrocephalus (obstructive and nonobstructive) and complex medical and surgical problems precluding traditional distal shunt termini. Both patients underwent successful placement of a VI shunt with distal catheter placement into the right iliac crest using a small right-angle connector and small cranial fixation plate to prevent backout of the catheter.

DISCUSSION AND CONCLUSION

We report the first demonstration of successful placement of a VI shunt in 2 adult patients with evidence of shunt functionality and improved neurological outcome. We propose that the placement of a VI shunt is an easy and viable option when more traditional shunt methods are not available for use.

Intra-osseous cerebrospinal fluid shunts-Overview of past and present clinical and experimental evidence

In the history of hydrocephalus treatment, a variety of diversion sites have been explored to ensure an adequate alternative when the peritoneum was not a feasible option. An interesting choice was the elimination of excessive cerebrospinal fluid (CSF) in the skeletal system. The purpose of this review was to evaluate all shunting systems that have been implemented in bone structures and to determine their therapeutic potential. All articles pertaining to bone derivations were selected from PubMed, Medline, EBSCO and Scopus, using relevant search terms. The search revealed 6 types of osseous shunts that have been used throughout history: vertebral, diploic, ventriculomastoid, ventriculoiliac, ventriculosternal and ventriculohumeral. Some of them are purely of historical significance, but data from more recent clinical and experimental studies have rendered this type of receptacle a potential site for diverting CSF. Having knowledge of all the alternatives used in cases of refractory hydrocephalus is vital for choosing the appropriate surgical intervention.

Ventriculo-humeral shunt: a cadaveric feasibility study with application to treating hydrocephalus

PURPOSE

Intraosseous vascular access is often used when vascular access is difficult. However, the use of this space for a receptacle for cerebrospinal fluid (CSF) diversion has been scantly considered.

MATERIALS AND METHODS

Six upper limbs of fresh frozen cadavers were used for this study. In the supine position, a small hole was drilled through the outer cortex of the proximal humerus and into the medullary cavity. A 16-gauge needle was placed into the hole in the humerus and 150 cc of saline infused. Next, the adjacent axillary vein and tributaries were dissected to observe dilation or the presence of the blue-colored saline. For part two of the study, shunt tubing was passed subcutaneously from a supraclavicular incision to the hole made in the humerus. Range of motion of the shoulder was then performed.

RESULTS

On all sides, all 150 cc of fluid was easily infused into the humerus. No specimen was found to have leakage from the drill hole site or into the extravascular soft tissues. With dissection of the axillary vein and its tributaries, all sides were found to have engorgement of these vessels. No tension was placed on the distal shunt tubing with full range of motion of the shoulder.

CONCLUSION

Based on our study, the humerus is another option available to the neurosurgeon for CSF diversion.

From the heart to the bladder-particularities of ventricular shunt topography and the current status of cerebrospinal fluid diversion sites

Hydrocephalus represents the pathological elevation of cerebrospinal fluid (CSF) levels as a consequence of various embryological or acquired defects. Although the classic method of treatment is by means of diverting the CSF from the ventricular system towards the peritoneum, there are other sites of diversion that have proven their efficiency through time, in the context of complications related to the more common option of intraperitoneal insertion. The aim of the review is to assess and organize a database of all the types of shunt locations from the oldest shunt attempts until present, using Pubmed and Medline and to underline the particularities related to technique, indications, complications and associated epidemiological background. Current literature reveals up to 36 sites of diversion of CSF with a diverse topography varying from cephalic regions such as venous sinuses or mastoid bone, thoracic elements such as the heart or the pleura and abdominopelvic segments such as the peritoneum or the urinary bladder. Several atypical locations were studied such as the fallopian and intestinal shunts. Although ventriculoperitoneal and ventriculoatrial shunts are the most commonly used shunts today, there are some systems such as the ventriculosinusal and ventriculolymphatic shunts that prove to be equally as efficient. The successful treatment of hydrocephalus requires a complete comprehension of the indications and therapeutic options and a reliable evaluation of the risks and possible complications. The profile of cerebral ventricular shunts is highly dynamic and the spectrum of cerebrospinal fluid diversion offers multiple solutions in the benefit of the patient.