Charles G. Kulwin, Ravi H. Gandhi, Neal B. Patel and Troy D. Payner
Michael S. Turner, Ha Son Nguyen, Troy D. Payner and Aaron A. Cohen-Gadol
Posterior fossa cysts are usually divided into Dandy-Walker malformations, arachnoid cysts, and isolated and/or trapped fourth ventricles. Shunt placement is a mainstay treatment for decompression of these fluid collections when their expansion becomes symptomatic. Although several techniques to drain symptomatic posterior fossa cysts have been described, each method carries its own advantages and disadvantages. This article describes an alternative technique.
In 10 patients, the authors used an alternative technique involving stereotactic and endoscopic methods to place a catheter in symptomatic posterior fossa cysts across the tentorium. Discussion of these cases is included, along with a review of various approaches to shunt placement in this region and recommendations regarding the proposed technique.
No patient suffered intracranial hemorrhage related to the procedure and catheter implantation. All 3 patients who underwent placement of a new transtentorial cystoperitoneal shunt and a new ventriculoperitoneal shunt did not suffer any postoperative complication; a decrease in the size of their posterior fossa cysts was evident on CT scans obtained during the 1st postoperative day. Follow-up CT scans demonstrated either stable findings or further interval decrease in the size of their cysts. In 1 patient, the postoperative head CT demonstrated that the transtentorial catheter terminated posterior to the right parietal occipital region without entering the retrocerebellar cyst. This patient underwent a repeat operation for proximal shunt revision, resulting in an acceptable catheter implantation. The patient in Case 8 suffered from a shunt infection and subsequently underwent hardware removal and aqueductoplasty with stent placement. The patient in Case 9 demonstrated a slight increase in fourth ventricle size and was returned to the operating room. Exploration revealed a kink in the tubing connecting the distal limb of the Y connector to the valve. The Y connector was replaced with a T connector, and 1 week later, CT scans exhibited interval decompression of the ventricles. This patient later presented with cranial wound breakdown and an exposed shunt. His shunt hardware was removed and he was treated with antibiotics. He later underwent reimplantation of a lateral ventricular and transtentorial shunt and suffered no other complications during a 3-year follow-up period.
The introduction of endoscopic and stereotactic techniques has expanded the available treatment possibilities for posterior fossa cysts.
Todd J. Wannemuehler, Kolin E. Rubel, Benjamin K. Hendricks, Jonathan Y. Ting, Troy D. Payner, Mitesh V. Shah and Aaron A. Cohen-Gadol
Craniopharyngiomas have historically been resected via transcranial microsurgery (TCM). In the last 2 decades, the extended endoscopic endonasal (transtuberculum) approach to these tumors has become more widely accepted, yet there remains controversy over which approach leads to better outcomes. The purpose of this study is to determine whether differences in outcomes were identified between TCM and extended endoscopic endonasal approaches (EEEAs) in adult patients undergoing primary resection of suprasellar craniopharyngiomas at a single institution.
A retrospective review of all patients who underwent resection of their histopathologically confirmed craniopharyngiomas at the authors' institution between 2005 and 2015 was performed. Pediatric patients, revision cases, and patients with tumors greater than 2 standard deviations above the mean volume were excluded. The patients were divided into 2 groups: those undergoing primary TCM and those undergoing a primary EEEA. Preoperative patient demographics, presenting symptoms, and preoperative tumor volumes were determined. Extent of resection, tumor histological subtype, postoperative complications, and additional outcome data were obtained. Statistical significance between variables was determined utilizing Student t-tests, chi-square tests, and Fisher exact tests when applicable.
After exclusions, 21 patients satisfied the aforementioned inclusion criteria; 12 underwent TCM for resection while 9 benefitted from the EEEA. There were no significant differences in patient demographics, presenting symptoms, tumor subtype, or preoperative tumor volumes; no tumors had significant lateral or prechiasmatic extension. The extent of resection was similar between these 2 groups, as was the necessity for additional surgery or adjuvant therapy. CSF leakage was encountered only in the EEEA group (2 patients). Importantly, the rate of postoperative visual improvement was significantly higher in the EEEA group than in the TCM group (88.9% vs 25.0%; p = 0.0075). Postoperative visual deterioration only occurred in the TCM group (3 patients). Recurrence was uncommon, with similar rates between the groups. Other complication rates, overall complication risk, and additional outcome measures were similar between these groups as well.
Based on this study, most outcome variables appear to be similar between TCM and EEEA routes for similarly sized tumors in adults. The multidisciplinary EEEA to craniopharyngioma resection represents a safe and compelling alternative to TCM. The authors' data demonstrate that postoperative visual improvement is statistically more likely in the EEEA despite the increased risk of CSF leakage. These results add to the growing evidence that the EEEA may be considered the approach of choice for resection of select confined primary craniopharyngiomas without significant lateral extension in centers with experienced surgeons. Further prospective, multiinstitutional collaboration is needed to power studies capable of fully evaluating indications and appropriate approaches for craniopharyngiomas.
Bradley N. Bohnstedt, Mary Ziemba-Davis, Rishabh Sethia, Troy D. Payner, Andrew DeNardo, John Scott and Aaron A. Cohen-Gadol
The deep and difficult-to-reach location of basilar apex aneurysms, along with their location near critical adjacent perforating arteries, has rendered the perception that microsurgical treatment of these aneurysms is risky. As a result, these aneurysms are considered more suitable for treatment by endovascular intervention. The authors attempt to compare the immediate and long-term outcomes of microsurgery versus endovascular therapy for this aneurysm subtype.
A prospectively maintained database of 208 consecutive patients treated for basilar apex aneurysms between 2000 and 2012 was reviewed. In this group, 161 patients underwent endovascular treatment and 47 were managed microsurgically. The corresponding records were analyzed for presenting characteristics, postoperative complications, discharge status, and Glasgow Outcome Scale (GOS) scores up to 1 year after treatment and compared using chi-square and Student t-tests.
Among these 208 aneurysms, 116 (56%) were ruptured, including 92 (57%) and 24 (51%) of the endovascularly and microsurgically managed aneurysms, respectively. The average Hunt and Hess grade was 2.4 (2.4 in the endovascular group and 2.2 in the microsurgical group; p = 0.472). Postoperative complications of cranial nerve deficits and hemiparesis were more common in patients treated microsurgically than endovascularly (55.3% vs 16.2%, p < 0.05; and 27.7% vs 10.6%, p < 0.05, respectively). However, aneurysm remnants and need for retreatment were more common in the endovascular than the microsurgical group (41.3% vs 2.3%, p < 0.05; and 10.6% vs 0.0%, p < 0.05, respectively). Stent placement significantly reduced the need for retreatment. Rehemorrhage rates and average GOS score at discharge and 1 year after treatment were not statistically different between the two treatment groups.
Patients with basilar apex aneurysms were significantly more likely to be treated via endovascular management, but compared with those treated microsurgically, they had higher rates of recurrence and need for retreatment. The current study did not detect an overall difference in outcomes at discharge and 1 year after either treatment modality. Therefore, in a select group of patients, microsurgical treatment continues to play an important role.
Daniel H. Fulkerson, Jason M. Voorhies, Troy D. Payner, Thomas J. Leipzig, Terry G. Horner, Kathleen Redelman and Aaron A. Cohen-Gadol
Pediatric intracranial aneurysms are rare lesions that differ from their adult counterparts. Aneurysms involving the middle cerebral artery (MCA) are particularly challenging to treat in children, as they are often fusiform and cannot undergo direct clipping alone. The authors recently treated a patient with a heavily calcified, dysplastic, left-sided MCA aneurysm. The present study was performed to evaluate the authors' previous operative and follow-up experience with these difficult lesions.
The authors performed a review of a prospectively maintained database of all aneurysms treated at Methodist Hospital in Indianapolis, Indiana, from January 1990 through November 2010. Relevant operative notes, clinical charts, and radiological reports were reviewed for all patients 18 years of age or younger.
A total of 2949 patients with aneurysms were treated over the study period, including 28 children (0.95%). Seven children harbored MCA aneurysms. Five of these 7 aneurysms (71.4%) were fusiform. Two patients were treated with direct clipping, 2 underwent parent vessel occlusion without bypass, and 3 underwent aneurysm trapping with extracranial-intracranial vessel bypass. Long-term follow-up data were available in 6 cases. All 6 patients had a 1-year follow-up Glasgow Outcome Scale score of 5. Long-term radiological follow-up was available in 4 patients. One patient required a reoperation for a recurrent aneurysm 4 years after the initial surgery.
Middle cerebral artery aneurysms in children are often fusiform, giant, and incorporate the origins of proximal artery branches. Direct clipping may not be possible; trapping of the lesion may be required. Children seem to tolerate surgical trapping with or without bypass extremely well. Aggressive therapy of these rare lesions in children is warranted, as even patients presenting with a poor clinical grade may have excellent outcomes. Long-term surveillance imaging is necessary because of the risk of aneurysm recurrence.
Todd D. Vogel, Charles G. Kulwin, Andrew J. DeNardo, Troy D. Payner, Joel C. Boaz and Daniel H. Fulkerson
Aneurysms in children are rare and potentially devastating lesions. The authors report the case of a 16-year-old girl with a complicated medical history related to a chiasmal glioma diagnosed at 18 months of age. She had previously received multiple modalities of radiation treatment, including external beam, proton therapy, and Gamma Knife. She presented with hemorrhage centered in the tumor and extending into the ventricular space. There was no subarachnoid blood. Magnetic resonance imaging demonstrated the hemorrhage and tumor anatomy. Magnetic resonance angiography revealed an aneurysm at the internal carotid artery bifurcation, but the lesion was more clearly delineated on CT angiography. A comparison MR imaging study obtained 6 months earlier, even in retrospect, did not show evidence of an aneurysm. This case illustrates the salient point that the clinician must search for vascular lesions in the patient with spontaneous “tumor bleeding,” especially if that patient has risk factors for aneurysm formation. The authors also suggest that a CT angiogram is better at radiographically demonstrating an intratumoral aneurysm than an MR angiogram in this scenario.
Nicolas W. Villelli, David M. Lewis, Thomas J. Leipzig, Andrew J. DeNardo, Troy D. Payner and Charles G. Kulwin
Intraoperative angiography can be a valuable tool in the surgical management of vascular disorders in the CNS. This is typically accomplished via femoral artery puncture; however, this can be technically difficult in patients in the prone position. The authors describe the feasibility of intraoperative angiography via the popliteal artery in the prone patient.
Three patients underwent intraoperative spinal angiography in the prone position via vascular access through the popliteal artery. Standard angiography techniques were used, along with ultrasound and a micropuncture needle for initial vascular access. Two patients underwent intraoperative angiography to confirm the obliteration of dural arteriovenous fistulas. The third patient required unexpected intraoperative angiography when a tumor was concerning for a vascular malformation in the cervical spine.
All 3 patients tolerated the procedure without complication. The popliteal artery was easily accessed without any adaptation to typical patient positioning for these prone-position cases. This proved particularly beneficial when angiography was not part of the preoperative plan.
Intraoperative angiography via the popliteal artery is feasible and well tolerated. It presents significant benefit when obtaining imaging studies in patients in a prone position, with the added benefit of easy access, familiar anatomy, and low concern for catheter thrombosis or kinking.
Troy D. Payner, Terry G. Horner, Thomas J. Leipzig, John A. Scott, Richard L. Gilmor and Andrew J. DeNardo
The benefit of using intraoperative angiography (IA) during aneurysm surgery is still uncertain.
Object. In this prospective study, the authors evaluate the radiographically demonstrated success of surgical treatment in 151 consecutive patients harboring 173 aneurysms who selectively underwent IA examination. The authors also assess the frequency with which IA led to repositioning of the aneurysm clip.
Methods. Intraoperative angiography was used selectively in this series, based on the surgeon's concern about the potential for residual aneurysm, distal branch occlusion, or parent vessel stenosis. Specific variables were analyzed to determine their impact on the incidence of clip repositioning and the accuracy of IA was evaluated by direct comparison with postoperative angiography (PA) in 90% of the cases in which IA was used.
Conclusions. The selective use of IA led to successful treatment as shown by PA, with a low incidence of unexpected residual aneurysm (3.2%), distal branch occlusion (1.9%), and parent vessel stenosis (0%). Intraoperative angiography led to immediate repositioning of the aneurysm clip in 27% of the cases. Anterior cerebral artery aneurysms required clip repositioning less often and superior hypophyseal artery aneurysms required repositioning more often than aneurysms in other locations. Large and giant aneurysms required clip repositioning more often than small aneurysms; however, they were also more likely to display false success on IA as determined by PA. Aneurysms arising along the internal carotid artery were more likely to display successful clipping on IA, as determined by PA, than were aneurysms in other locations.
The results of this series support the selective use of IA in the treatment of complex aneurysms, particularly large and giant aneurysms as well as superior hypophyseal artery aneurysms. As measured by PA, IA will improve the outcome of these patients.