✓ Two cases of intravascular infusion of Pantopaque occurring during myelography are reported. Cerebrospinal fluid-venous fistula is described as the mechanism of escape of Pantopaque from the subarachnoid space into a venous plexus and as a possible explanation of postspinal intracranial hypotension.
Paul M. Lin and Joseph Clarke
Kenneth Tuerk, Norman E. Chase, Irvin I. Kricheff, Joseph P. Lin and Joseph Ransohoff
✓ Twenty patients with posterior communicating artery aneurysms were treated with common carotid ligation. Postligation visualization was accomplished in 16 cases by ipsilateral brachial angiography. Two other aneurysms were visualized by contralateral brachial and contralaterial carotid angiography. The size of the aneurysm was measured before and after ligation. The relationship of postoperative reduction in size to preoperative angiographic characteristics was studied. Reduction in the size of the aneurysm occurred most often when preoperative angiography showed that the sac was long and its neck narrow, and when there was stasis of contrast material in the aneurysm.
Ajax E. George, Joseph P. Lin and Robert A. Morantz
✓ The angiographic demonstration of a rare case of persistent trigeminal artery aneurysm is reported. The incidence of persistent trigeminal artery in the authors' series is 0.6%. Approximately 14% of patients with a persistent trigeminal artery also have an intracranial aneurysm. The embryology involved and related cases are reviewed.
James D. Lin, Lee A. Tan, Chao Wei, Jamal N. Shillingford, Joseph L. Laratta, Joseph M. Lombardi, Yongjung J. Kim, Ronald A. Lehman Jr. and Lawrence G. Lenke
The S2-alar-iliac (S2AI) screw is an increasingly popular method for spinopelvic fixation. The technique of freehand S2AI screw placement has been recently described. The purpose of this study was to demonstrate, through a CT imaging study of patients with spinal deformity, that screw trajectories based on the posterior superior iliac spine (PSIS) and sacral laminar slope result in reliable freehand S2AI trajectories that traverse safely above the sciatic notch.
Fifty consecutive patients (age ≥ 18 years) who underwent primary spinal deformity surgery were included in the study. Simulated S2AI screw trajectories were analyzed with 3D visualization software. The cephalocaudal coordinate for the starting point was 15 mm cephalad to the PSIS. The mediolateral coordinate for the starting point was in line with the lateral border of the dorsal foramina. The cephalocaudal screw trajectory was perpendicular to the sacral laminar slope. Screw trajectories, lengths, and distance above the sciatic notch were measured.
The mean sagittal screw angle (cephalocaudal angulation) was 44.0° ± 8.4° and the mean transverse angle (mediolateral angulation) was 37.3° ± 4.3°. The mean starting point was 5.9 ± 5.8 mm distal to the caudal border of the S1 foramen. The mean screw length was 99.9 ± 18.6 mm. Screw trajectories were on average 8.5 ± 4.3 mm above the sciatic notch. A total of 97 of 100 screws were placed above the sciatic notch. In patients with transitional lumbosacral anatomy, the starting point on the lumbarized/sacralized side was 3.4 mm higher than on the contralateral unaffected side.
The PSIS and sacral laminar slope are two important anatomical landmarks for freehand S2AI screw placement.
Ronny L. Rotondo, Wendy Folkert, Norbert J. Liebsch, Yen-Lin E. Chen, Frank X. Pedlow, Joseph H. Schwab, Andrew E. Rosenberg, G. Petur Nielsen, Jackie Szymonifka, Al E. Ferreira, Francis J. Hornicek and Thomas F. Delaney
Spinal chordomas can have high local recurrence rates after surgery with or without conventional dose radiation therapy (RT). Treatment outcomes and prognostic factors after high-dose proton-based RT with or without surgery were assessed.
The authors conducted a retrospective review of 126 treated patients (127 lesions) categorized according to disease status (primary vs recurrent), resection (en bloc vs intralesional), margin status, and RT timing.
Seventy-one sacrococcygeal, 40 lumbar, and 16 thoracic chordomas were analyzed. Mean RT dose was 72.4 GyRBE (relative biological effectiveness). With median follow-up of 41 months, the 5-year overall survival (OS), local control (LC), locoregional control (LRC), and distant control (DC) for the entire cohort were 81%, 62%, 60%, and 77%, respectively. LC for primary chordoma was 68% versus 49% for recurrent lesions (p = 0.058). LC if treated with a component of preoperative RT was 72% versus 54% without this treatment (p = 0.113). Among primary tumors, LC and LRC were higher with preoperative RT, 85% (p = 0.019) and 79% (0.034), respectively, versus 56% and 56% if no preoperative RT was provided. Overall LC was significantly improved with en bloc versus intralesional resection (72% vs 55%, p = 0.016), as was LRC (70% vs 53%, p = 0.035). A trend was noted toward improved LC and LRC for R0/R1 margins and the absence of intralesional procedures.
High-dose proton-based RT in the management of spinal chordomas can be effective treatment. In patients undergoing surgery, those with primary chordomas undergoing preoperative RT, en bloc resection, and postoperative RT boost have the highest rate of local tumor control; among 28 patients with primary chordomas who underwent preoperative RT and en bloc resection, no local recurrences were seen. Intralesional and incomplete resections are associated with higher local failure rates and are to be avoided.
Mohamad Bydon, Joseph A. Lin, Rafael de la Garza-Ramos, Daniel M. Sciubba, Jean Paul Wolinsky, Timothy F. Witham, Ziya L. Gokaslan and Ali Bydon
This study was undertaken to compare surgical outcomes between patients with atlantoaxial versus subaxial cervical synovial cysts (CSCs) and to compare outcomes between patients who underwent decompression alone versus decompression and fusion for the treatment of CSCs.
The authors present a series of 17 cases involving patients treated at their institution and report the surgical outcomes. Due to the rarity of CSCs, a meta-analysis was conducted, and results of the literature search were combined with the case series to enhance the power of the study.
Seventeen patients underwent surgical treatment for CSCs at our institution: 3 patients (17.6%) had atlantoaxial cysts and 14 (82.3%) had subaxial cysts. Of the 17 patients, 16 underwent a decompression and fusion; most patients experienced symptom resolution at last follow-up, and there were no cyst recurrences. A total of 54 articles (including the current series) and 101 patients were included in the meta-analysis. The mean age at presentation was 64 ± 13.9 years, and the most common symptoms were motor and sensory deficits. Forty-one patients (40.6%) presented with atlantoaxial cysts, and 60 (59.4%) with subaxial cysts. There were no significant differences between groups in terms of presenting symptoms, Nurick scores, surgical treatment, or surgical outcomes. Fifty-two patients (51.4%) underwent surgical decompression without fusion, while 49 patients (48.6%) underwent fusion. The preoperative Nurick scores were significantly lower in the fused group (p = 0.001), with an average score of 1.32 compared with 2.75 in the nonfused group. After a mean follow-up of 16.5 months, a difference of means analysis between final and preoperative Nurick scores revealed that patients who received a decompression alone improved on average 1.66 points (95% CI 1.03–2.29) compared with 0.8 points (95% CI 0.23–1.39) in the fused group (p = 0.004). However, there was no statistically significant difference in symptom resolution between the groups, and the rate of cyst recurrence was found to be 0%.
In this study, patients with CSCs had similar outcomes regardless of cyst location and regardless of whether they underwent decompression only or fusion. In the authors' institutional experience, 16 of 17 patients underwent fusion due to underlying spinal instability. While there were no reports of cyst recurrence in their series or in the literature in patients who only received decompression, this is likely due to the limited follow-up time available for the study population. Longer follow-up and prospective and biomechanical studies are needed to corroborate these findings.