Complication-Effectiveness Analysis for Unruptured Intracranial Aneurysm Surgery

Aneurysm surgery

Neurosurgery 78:648–659, 2016

The aim of intervention for unruptured intracranial aneurysms (UIAs) is safe, effective treatment.

OBJECTIVE: To analyze a prospective database for variables influencing the risk of surgery to produce a risk model adjusting this risk for effectively treated aneurysms.

METHODS: First, we identified variables to create a model from multiple logistic regression for complications of surgery leading to a 12-month modified Rankin Scale score .1. Second, we established the long-term cumulative incidence of freedom from retreatment or rupture (treated aneurysm) from Kaplan-Meier analysis. Third, we combined these analyses to establish a model of risk of surgery per effective treatment.

RESULTS: One thousand twelve patients with 1440 UIA underwent 1080 craniotomies. We found that 10.1% (95% confidence interval [CI], 8.4-12.0) of craniotomies resulted in a complication leading to a modified Rankin Scale score .1 at 12 months. Logistic regression found age (odds ratio, 1.04; 95% CI, 1.02-1.06), size (odds ratio, 1.12; 95% CI, 1.09-1.15), and posterior circulation location (odds ratio, 2.95; 95% CI, 1.82-4.78) to be significant. Cumulative 10-year risk of retreatment or rupture was 3.0% (95% CI, 1.3-7.0). The complication-effectiveness model was derived by dividing the complication risk by the 10-year cumulative freedom from retreatment or rupture proportion. Risk per effective treatment ranged from 1% for a 5-mm anterior circulation UIA in a 20-year-old patient to 70% for a giant posterior circulation UIA in a 70-year-old patient.

CONCLUSION: Complication-effectiveness analyses increase the information available with regard to outcome for the management of UIAs.

Surgical Clipping of Very Small Unruptured Intracranial Aneurysms

very small aneurysms

Neurosurgery 78:47–52, 2016

Treatment of very small unruptured intracranial aneurysms (VSUIAs, defined as ≤3 mm) can be indicated in selected circumstances. The feasibility and outcomes of endovascular therapy for VSUIAs have been recently published; however, the efficacy and complication rate of surgical clipping has not been reported in any large series to date.

OBJECTIVE: We conducted a multicenter study to examine surgical outcomes for VSUIAs.

METHODS: All consecutive patients undergoing surgery for a VSUIA in 4 neurosurgical centers between October 2001 and December 2012 were retrospectively analyzed.

RESULTS: In the study, 183 patients (128 women, mean age 51.3 years) were treated with 190 procedures for a total of 228 aneurysms. Most were anterior circulation aneurysms (n = 215). The majority were directly clipped (n = 222, 97.4%), with coagulation or wrapping in the remainder. After 1 reoperation for incomplete clipping, postoperative imaging of 225 aneurysms confirmed complete occlusion in 221 (98.2%), 1 neck remnant (0.44%), and 3 partial occlusions (1.3%). Mortality was 0%. Early postoperative neurological deficit developed in 12 patients (6.6%); posterior circulation location was a significant risk factor for early neurological deficit (P < .001). Middle cerebral artery aneurysms had the lowest rate of postoperative deficits at 1.5% (P = .023). After the initial 30-day perioperative period, all deficits related to treatment of posterior circulation aneurysms recovered; overall neurological morbidity decreased to 2.7% with no mortality.

CONCLUSION: VSUIA clipping is highly effective and is associated with a low morbidity rate. For VSUIAs selected for treatment, our data support surgical clipping as the modality of choice.

KEY WORDS:

High-dose proton-based radiation therapy in the management of spine chordomas

spine_chordoma

J Neurosurg Spine 23:788–797, 2015

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.

Methods 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.

Results 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.

Conclusions 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.

Application of intraoperative motor evoked potential monitoring during giant internal carotid artery aneurysm surgery using prolonged temporary occlusion

Application of intraoperative motor evoked potential monitoring during giant internal carotid artery aneurysm surgery using prolonged temporary occlusion

Acta Neurochir (2015) 157:1833–1840

Clipping and bypass surgery are common therapeutic options for the management of giant internal carotid artery (ICA) aneurysms. However, potential ischemic risks may be exaggerated by prolonged temporary occlusion (PTO) during the surgery. Monitoring motor-evoked potentials (MEPs) is a sensitive technique for detecting potential ischemia intraoperatively. This preliminary study was designed to evaluate the effectiveness of applying MEP monitoring during giant ICA aneurysm surgery using PTO.

Methods From July 2009 to July 2012, 11 patients with giant ICA aneurysms who could not pass the preoperative hemodynamic evaluations were enrolled in this study. MEP monitoring was utilized intraoperatively in all cases. Clipping was performed if there were no significant MEP changes under PTO. A variant extracranial-to-intracranial (EC-IC) bypass was performed if there was reproducible loss of MEP signals after PTO or unclippable anatomic features.

Results Five patients underwent clipping alone and six underwent bypass. There were no significant differences in baseline clinical data between the two groups. The overall percentage of patients with good outcomes (Glasgow Outcome Score≥4) improved from 72.7 % (8/11) postoperatively to 90.9 % (10/11) after 26.0±9.5 months of follow-up. There were no significant differences between the clipping and bypass groups regarding short- and long-term outcomes (p=0.545 and p=1.000).

Conclusions MEP monitoring is useful for evaluating the safety of PTO, surgical strategy, and outcomes of giant ICA aneurysm surgery. Direct clipping during safe PTO under intraoperative MEP monitoring is applicable for giant ICA aneurysms. Its use achieved favorable outcomes by indicating the need for bypass surgery.

Adenosine-induced transient asystole during intracranial aneurysm surgery

Adenosine-induced transient asystole

Acta Neurochir (2015) 157:1879–1886

Several flow-arrest techniques have been introduced for the treatment of complex aneurysms that cannot be treated with conventional clipping or endovascular coil embolization. Adenosine-induced transient asystole is an alternative method of flow arrest. However, given the limited number of studies that have reported on this topic, there is no consensus regarding the dose, regimen, efficacy, and potential risks of adenosine.

Method A total of 22 aneurysms in 22 different patients that underwent adenosine-induced transient asystole during aneurismal neck clipping within the past 4 years were retrospectively reviewed. Adenosine was administrated intravenously in a test-incremental manner (starting with 6–12 mg and then giving additional doses as needed) in 11 patients and in an estimated manner (pre-calculated as 0.3–0.4 mg/kg) in 11 patients.

Results Overall, the study consisted of 18 unruptured saccular aneurysms, three ruptured saccular aneurysms, and a ruptured pseudoaneurysm. Adenosine-induced transient asystole was used in cases of temporary clipping inability, wide necked aneurysm, deep-seated aneurysm, or a thin aneurysm wall. The number of administrations, dose (mg/kg in ideal body weight) and duration of asystole were 1–4 (mean, 2.3) times, 0.08–1.27 (mean, 0.36) mg/kg and 0–30 (mean 13) seconds in the test-incremental manner and 1–2 (mean, 1.09) times, 0.24–0.42 (mean, 0.34) mg/kg and 13–41 (mean, 24) seconds in the estimated manner, respectively. There was a linear relationship between the dose and the duration of asystole. Twenty out of 22 aneurysms were clipped successfully with adenosine-induced transient asystole. However, in the other two cases, additional suction decompression was required for the final clipping. Adenosine-related cardiologic complications occurred in two cases of self-limited atrial fibrillation during restoration of the cardiac rhythm.

Conclusions In our experience, adenosine-induced transient asystole was safe and helpful for satisfactory clipping of a complicated aneurysm. An estimated dose injection of adenosine was more convenient than the test-incremental method and did not result in serious cardiologic problems.

Intracranial meningioma surgery in the elderly (over 65 years): prognostic factors and outcome

Tuberculum Sellae Meningiomas

Acta Neurochir 157 (9): 1549-1557

Meningiomas are more prevalent in elderly individuals; however, the surgical outcome and prognostic factors in this age group are unclear. This retrospective study aimed to identify the prognostic factors of elderly patients with intracranial meningiomas who underwent surgical resection.

Methods

Eighty-six patients (aged ≥65) diagnosed with an intracranial meningioma were surgically treated at our department. The clinical, radiological, and follow-up data were retrospectively reviewed. Univariate and multivariate logistic analyses were performed to identify relationships between factors [age, sex, neurological condition, concomitant disease, American Society of Anesthesiology (ASA) classification, preoperative Karnofsky Performance Scale (KPS) score, tumor location and size, peritumoral edema, and Simpson resection grade] and outcome.

Results

One patient (1.2 %) died within 30 days of surgery. The morbidity rate was 37.2 %. Postoperative morbidities occurred more frequently in the patients with preoperative neurological deficits than in those without (p = 0.049). Univariate analysis identified significant relationships between a low KPS score (≤70) at discharge and preoperative neurological deficits, low preoperative KPS score (≤70), and critical tumor location (p < 0.001, p < 0.001, and p = 0.04, respectively). In the multivariate logistic analysis, only the preoperative KPS score remained significant for the KPS score at discharge (p = 0.005); there was no significant association with the most recent KPS score.

Conclusion

The outcome of intracranial meningioma resection in elderly individuals is favorable if the preoperative KPS score is >70 and no neurological deficits are present. Treatment decisions should be patient-specific, and additional factors should be considered when operations are performed in patients with a low preoperative KPS score or neurological deficits.

Pineal cyst resection in the absence of ventriculomegaly or Parinaud’s syndrome

Pineal cyst resection in the absence of ventriculomegaly or Parinaud’s syndrome

J Neurosurg 123:352–356, 2015

Surgical indications for patients with pineal cysts are controversial. While the majority of patients harboring a pineal cyst require no treatment, surgery is a well-accepted option for a subset of those patients with secondary hydrocephalus or Parinaud’s syndrome. The majority of pineal cysts are identified incidentally during workup for other potential conditions, which may or may not be related to the presence of the cyst. In the absence of clear obstruction of CSF pathways, the treatment of presumed symptomatic pineal cysts is debatable. To clarify the role of surgery in these borderline cases, the authors reviewed their experience with resection of pineal cysts in the absence of ventriculomegaly or Parinaud’s syndrome.

Methods The authors retrospectively reviewed medical records and imaging of all patients surgically treated between 2001 and 2014 with a pineal cyst in the absence of ventriculomegaly and Parinaud’s syndrome. The presenting symptoms, preoperative cyst size, preoperative radiographic aqueductal compression, extent of resection, and radiographic and clinical follow-up were documented.

Results Eighteen patients (14 female and 4 male; mean age 24 years, range 4–47 years) underwent cyst resection in the absence of ventriculomegaly or Parinaud’s syndrome. Presenting symptoms included headache (17 patients), visual disturbances (10 patients), gait instability (5 patients), dizziness (5 patients), episodic loss of consciousness (2 patients), and hypersomnolence (1 patient). The mean preoperative cyst diameter was 1.5 cm (range 0.9–2.2 cm). All patients had a complete resection. At a mean clinical follow-up of 19.1 months (range postoperative to 71 months), 17 (94%) patients had resolution or improvement of their presenting symptoms.

Conclusions: The authors’ results suggest that ventriculomegaly and Parinaud’s syndrome are not absolute requisites for a pineal cyst to be symptomatic. Analogous to colloid cysts of the third ventricle, intermittent occlusion of cerebrospinal fluid pathways may cause small pineal cysts to become intermittently symptomatic. A select cohort of patients with pineal cysts may benefit from surgery despite a lack of hydrocephalus or other obvious compressive pathology.

Influence of cumulative surgical experience on the outcome of poor-grade patients with ruptured intracranial aneurysm

ICA aneurysm

Acta Neurochir (2015) 157:1–7

The expansion of endovascular techniques for intracranial aneurysms has led to a global decrease in vascular neurosurgery activity. This situation might impact neurosurgeons’ level of expertise, even though they all might have to deal with this surgically challenging pathology. In that context, we wanted to assess the impact of cumulative surgical experience on the outcome of patients with poor-grade subarachnoid haemorrhage (SAH) and intracerebral haemorrhage (ICH) treated by microsurgery.

Methods Sixty-seven patients who underwent surgery for a ruptured aneurysm with SAH and ICH, and a WFNS scale of IV/V, were included. Surgeries were performed by five surgeons, whose experience was judged by the total number of aneurysm surgeries performed. The outcome was assessed by three indicators: intraoperative rupture (IOR), early mortality, and the modified Rankin Scale at last follow-up. The time of IOR was reported on an IOR score. The correlation between surgical experience and outcome was assessed by linear regression. Nonlinear regression was used to assess the correlation of the data with a learning curve model.

Results The analysis showed an influence of surgical experience on intraoperative rupture, with no effect on long-term outcome. No influence was found on early mortality. Increased surgical experience seems to reduce IOR during aneurysm dissection and clip repositioning. Intraoperative rupture data fit Wright’s learning curve model.

Conclusion This study suggests a direct impact of cumulative experience on the course of ruptured aneurysm surgery and pleads for the use of training and simulation programmes dedicated to neurovascular surgery.

Radical resection of nongerminomatous pineal region tumors via the occipital transtentorial approach based on arachnoidal consideration

Occipital transtentorial

Acta Neurochir (2014) 156:2253–2262

The role of radical resection for nongerminomatous pineal region tumors is still controversial. The purpose of this study was to present the surgical results in a large series and evaluate the feasibility of radical surgical strategy.

Methods We retrospectively reviewed the records of 143 patients with nongerminomatous pineal region tumors surgically treated via an occipital transtentorial approach between 2000 and 2011. The tumor was small (<2 cm) in 14.7 % of patients, medium (2–4 cm) in 52.4 %, and large (>4 cm) in 32.9 %.

Results Gross total tumor removal was achieved in 91.6 % of patients, subtotal in 7.0 %, and partial in 1.4 %. Histological diagnosis was nongerminomatous germ cell tumor in 41.3 %, pineal parenchymal tumor in 14.7 %, glial tumors in 28.7 %, and miscellaneous in 15.4 %. The overall complication and mortality rate was 18.2 % and 0.7 %, respectively. Permanent morbidity occurred in 5.6 % of patients, including hemianopsia in 3.5 % and Parinaud syndrome in 2.1 %. Hydrocephalus was resolved in 82.1 % without surgery for the CSF diversion. Sixty-eight patients with malignant tumors underwent radiotherapy; 35 also received adjuvant chemotherapy. One hundred thirty patients were successfully followed up with a mean duration of 43 months. Finally, 86.9 % of the patients achieved a favorable functional outcome (mRS≤ 2), 3.1 % had an mRS score of 3, 1.5 % had an mRS score of 4, and 8.5 % had died (mRS=6).

Conclusions Radical surgery was recommended as the optimal treatment for nongerminomatous pineal region tumors. Favorable results could be achieved by experienced neurosurgeons. Hydrocephalus could be cured by radical tumor removal in the majority of cases. The occipital transtentorial approach was indicated for most pineal region tumors, but surgeon’s preference and experience should also be considered. New understanding of the arachnoid membranes of this region may be helpful for tumor resection.

Management of lumbar spinal stenosis: a survey among Dutch spine surgeons

lumbar stenosis

Acta Neurochir (2014) 156:2139–2145

Various surgical and non-surgical treatments for lumbar spinal stenosis (LSS) are widely adopted in clinical practice, but high quality randomised controlled trials to support these are often lacking, especially in terms of their relative benefit and risk compared with other treatment options. Therefore, an evaluation of agreement among clinicians regarding the indications and the choice for particular treatments seems appropriate.

Methods One hundred and six Dutch neurosurgeons and orthopaedic spine surgeons completed a questionnaire, which evaluated treatment options for LSS and expectations regarding the effectiveness of surgical and non-surgical treatments.

Results Responders accounted for 6,971 decompression operations and 831 spinal fusion procedures for LSS annually. Typical neurogenic claudication, severe pain/disability, and a pronounced constriction of the spinal canal were considered the most important indications for surgical treatment by the majority of responders. Non-surgical treatment was generally regarded as ineffective and believed to be less effective than surgical treatment. Interlaminar decompression was the preferred technique by 68 % of neurosurgeons and 52 % orthopaedic surgeons for the treatment of LSS. Concomitant fusion was applied in 12% of all surgery for LSS. Most surgeons considered spondylolisthesis as an indication and spinal instability as a definite indication for additional fusion.

Conclusions The current survey demonstrates a wide variety of preferred treatments of symptomatic LSS by Dutch spine surgeons. To minimise variety, national and international protocols based on high-quality randomised controlled trials and systematic reviews are necessary to give surgeons more tools to support everyday decision-making.

Practical surgical indicators to identify candidates for radical resection of insulo-opercular gliomas

Surgical indicators insular gliomas

J Neurosurg 121:1124–1132, 2014

Maximum resection of gliomas with minimum surgical complications usually leads to optimum outcomes for patients. Radical resection of insulo-opercular gliomas is still challenging, and selection of ideal patients can reduce risk and obtain better outcomes.

Methods. This retrospective study included 83 consecutively treated patients with newly diagnosed gliomas located at the insulo-opercular region and extending to the sylvian fissure around the primary motor and somatosensory cortices. The authors selected 4 characteristics as surgical indicators: clear tumor boundaries, negative enhancement, intact lenticulostriate arteries, and intact superior extremity of the central insular sulcus.

Results. Univariate analysis showed that tumors with clear boundaries were associated with higher rates of gross-total resection than were tumors with ambiguous boundaries (75.7% vs 19.6%). Tumors with negative enhancement compared with enhanced tumors were associated with lower frequency of tumor progression (32.0% vs 81.8%, respectively) and lower rates of surgical complications (14.0% vs 45.5%, respectively). Tumors with intact lenticulostriate arteries were associated with higher rates of gross-total resection than were tumors with involved lenticulostriate arteries (67.3% vs 11.8%, respectively). Tumors with intact superior extremity of the central insular sulcus were associated with higher rates of gross-total resection (57.4% vs 20.7%, respectively) and lower rates of surgical complications (18.5% vs 41.4%, respectively) than were tumors with involved anatomical structures. Multivariate analysis showed that clear tumor boundaries were independently associated with gross-total resection (p < 0.001). Negative enhancement was found to be independently associated with surgical complications (p = 0.005), overall survival times (p < 0.001), and progression-free survival times (p = 0.004). Independent associations were also found between intact lenticulostriate arteries and gross-total resection (p < 0.001), between intact lenticulostriate arteries and progression-free survival times (p = 0.026), and between intact superior extremity of the central insular sulcus and gross-total resection (p = 0.043). Among patients in whom all 4 indicators were present, prognosis was good (5- year survival rate 93.3%), resection rate was maximal (gross-total resection 100%), and surgical complication rate was minimal (6.7%). Also among these patients, overall rates of survival (p = 0.003) and progression-free survival (p = 0.005) were significantly higher than among patients in whom fewer indicators were present.

Conclusions. The authors propose 4 simple indicators that can be used to identify ideal candidates for radical resection of insulo-opercular gliomas, improve the outcomes, and promote maximum resection without introducing neurological complications. The indicators are clear tumor boundaries, negative enhancement, intact lenticulostriate arteries, and intact superior extremity of the central insular sulcus.

Effect of neoadjuvant temozolomide upon volume reduction and resection of diffuse low-grade glioma

Effect of neoadjuvant temozolomide upon volume reduction and resection of diffuse low-grade glioma

J Neurooncol (2014) 120:155–161

Maximal safe resection is associated with prolonged survival in patients with low-grade glioma (LGG). It has been suggested that neoadjuvant temozolomide may provide sufficient tumor shrinkage to facilitate aggressive surgical debulking. We examined the impact of temozolomide upon volume reduction and resectability of LGG.

We retrospectively identified 20 adult patients with biopsy proven, deemed not totally resectable LGGs, treated initially with temozolomide. Volumetric 3D (calculated from serial FLAIR images) and 2D tumor measurements were obtained prior to treatment and at 3 months post-treatment. The anticipated extent of resection (EOR) at the 2 time points was measured based on anatomical limitations, calculated as: [(total tumor volume – unresectable tumor volume)/total tumor volume] x 100. Eloquent cortex, deep structures and corpus callosum were considered unresectable.

Mean tumor volume was 68.4 cm3 pre-treatment and 49.5 cm3 at 3 months post-treatment. The mean change from baseline to 3 months after treatment was -32.5 % (p\0.001). Mean 2D pre-treatment area was 28.6 and 23.3 cm2 at 3 months post-treatment. The 2D change was also significant, with mean change of -17 % (p\0.001). 5 % had partial response; 40 % minor response; 45 % stable disease; and 10 % progressive disease by RANO criteria. Mean pretreatment anticipated EOR was 67.2 and 71.5 %at 3 months post-treatment. The mean change from baseline was 4.3 % (p = 0.10).

Our findings demonstrate significant volumetric and 2D reduction of LGG with temozolomide. Although this tumor shrinkage might facilitate radical surgical resection in some cases, our data failed to show statistically significant improvement in anticipated EOR.

Outcomes After Surgery and Radiotherapy for Spinal Myxopapillary Ependymoma

Spinal Myxopapillary Ependymoma

Neurosurgery 75:205–214, 2014

The role of radiotherapy after surgery for myxopapillary ependymoma (MPE) is unclear.

OBJECTIVE: To review long-term outcomes after surgery, with or without radiation, for spinal MPE.

METHODS: Fifty-one patients with spinal MPE treated from 1968 to 2007 were included. Associations between clinical variables and overall survival (OS), progressionfree survival (PFS), and local control (LC) were tested with Cox regression analysis.

RESULTS: The median age at diagnosis was 35 years (range, 8-63 years). Twenty patients (39%) had surgery alone, 30 (59%) had surgery plus radiotherapy (RT), and 1 (2%) had RT only. At a median follow-up of 11 years (range, 0.2-37 years), 10-year OS, PFS, and LC for the entire group were 93%, 63%, and 67%, respectively. Nineteen patients (37%) had disease recurrence, and the recurrence was mostly local (79%). Twenty-eight of 50 patients who had surgery (56%) had gross total resection; 10-year LC was 56% after surgery vs 92% after surgery and RT (log-rank P = .14); the median time of LC was 10.5 years for patients receiving gross total resection plus RT, and 4.75 years for gross total resection only (P = .03). Among 16 patients with subtotal resection and follow-up data, 10-year LC was 0% after surgery vs 65% for surgery plus RT (log-rank P = .008). On multivariate analyses adjusting for resection type, age older that 35 years at diagnosis and receipt of adjuvant radiation were associated with improved PFS (hazard ratio [HR]: 0.14, P = .003 and HR: 0.45, P = .009) and LC (HR: 0.22, P = .02 and HR: 0.45, P = .009).

CONCLUSION: Postoperative radiotherapy after resection of MPE was associated with improved PFS and LC.

Surgical treatment of pathological loss of lumbar lordosis (flatback)

Flatback

J Neurosurg Spine 21:160–170, 2014

Increased sagittal vertical axis (SVA) correlates strongly with pain and disability for adults with spinal deformity. A subset of patients with sagittal spinopelvic malalignment (SSM) have flatback deformity (pelvic incidence–lumbar lordosis [PI-LL] mismatch > 10°) but remain sagittally compensated with normal SVA. Few data exist for SSM patients with flatback deformity and normal SVA. The authors’ objective was to compare baseline disability and treatment outcomes for patients with compensated (SVA < 5 cm and PI-LL mismatch > 10°) and decompensated (SVA > 5 cm) SSM.

Methods. The study was a multicenter, prospective analysis of adults with spinal deformity who consecutively underwent surgical treatment for SSM. Inclusion criteria included age older than 18 years, presence of adult spinal deformity with SSM, plan for surgical treatment, and minimum 1-year follow-up data. Patients with SSM were divided into 2 groups: those with compensated SSM (SVA < 5 cm and PI-LL mismatch > 10°) and those with decompensated SSM (SVA ≥ 5 cm). Baseline and 1-year follow-up radiographic and health-related quality of life (HRQOL) outcomes included Oswestry Disability Index, Short Form–36 scores, and Scoliosis Research Society–22 scores. Percentages of patients achieving minimal clinically important difference (MCID) were also assessed.

Results. A total of 125 patients (27 compensated and 98 decompensated) met inclusion criteria. Compared with patients in the compensated group, patients in the decompensated group were older (62.9 vs 55.1 years; p = 0.004) and had less scoliosis (43° vs 54°; p = 0.002), greater SVA (12.0 cm vs 1.7 cm; p < 0.001), greater PI-LL mismatch (26° vs 20°; p = 0.013), and poorer HRQOL scores (Oswestry Disability Index, Short Form-36 physical component score, Scoliosis Research Society-22 total; p ≤ 0.016). Although these baseline HRQOL differences between the groups reached statistical significance, only the mean difference in Short Form–36 physical component score reached threshold for MCID. Compared with baseline assessment, at 1 year after surgery improvement was noted for patients in both groups for mean SVA (compensated –1.1 cm, decompensated +4.8 cm; p ≤ 0.009), mean PI-LL mismatch (compensated 6°, decompensated 5°; p < 0.001), and all HRQOL measures assessed (p ≤ 0.005). No significant differences were found between the compensated and decompensated groups in the magnitude of HRQOL score improvement or in the percentages of patients achieving MCID for each of the outcome measures assessed.

Conclusions. Decompensated SSM patients with elevated SVA experience significant disability; however, the amount of disability in compensated SSM patients with flatback deformity caused by PI-LL mismatch but normal SVA is underappreciated. Surgical correction of SSM demonstrated similar radiographic and HRQOL score improvements for patients in both groups. Evaluation of SSM should extend beyond measuring SVA. Among patients with concordant pain and disability, PI-LL mismatch must be evaluated for SSM patients and can be considered a primary indication for surgery.

Complications of occipitocervical fusion: a 316 cases retrospective analysis

Occipito-cervical fusion

Eur Spine J (2014) 23:1720–1724

Disorders in occipitocervical region are difficult to treat. Complications often occur after fusion surgery and may be life-threatening in severe cases. This study is to investigate the causes and treatment strategies for the postoperative complications of occipitocervical fusion.

Methods Between May 1985 and May 2011, 316 patients with various occipitocervical diseases underwent occipitocervical surgery, with or without internal fixation. Two physicians were assigned for patients follow-up. Their medical records and radiographs were reviewed and the postoperative complications, including those at the occipitocervical region and donor site, were analyzed.

Results Three hundred cases were followed up from 24 months to 26 years with an average of 9 years and 8 months, and the follow-up rate was 94.9 %. There were 16 cases with complications after surgery in the uninstrumented fusion group; the incidence was 33.3 %. These included 11 patients (22.9 %) with complications in occipitocervical region and five patients (11.9 %) with donor-site complications. 45 complications presented in the instrumented fusion group, the incidence was 17.9 %. These included 30 patients (11.9 %) with complications in occipitocervical region and 15 patients (5.9 %) with donorsite complications. Perioperative complications included vertebral artery injury, spinal cord injury, nerve root injury, suffocation, cerebrospinal fluid leakage, and infection. Mid- to long-term complications included bone-graft displacement or absorption, aggravated vertebral dislocation, improper screw placement, spinous process fracture, and internal fixation breakage. Donor-site complications were hematoma, pain and infection.

Conclusion The surgery of occipitocervical fusion carries a relative high risk for complications, especially if no instrumentation is used. The key points in reducing complications are the surgeon’s familiarity with the anatomy of occipitocervical region and the appropriate internal fixation.

Anaplastic astrocytomas: survival and prognostic factors in a surgical series

AA

Acta Neurochir (2014) 156:1053–1061

To study patient characteristics, prognostic factors and overall survival (OS) in a consecutive, surgical series of WHO grade III anaplastic astrocytomas (AA).

Methods Patients were identified from a prospective tumor database at Oslo University Hospital, Norway, and patients undergoing surgery for an AA from 2005–2012 were included. Patients’ medical charts were retrospectively reviewed for data collection.

Results A total of 99 adult patients with histologically verified AA were included. Median age was 52 years (20–81). Biopsy was conducted in 33 % and resection in 67 %. Adjuvant treatment with radiation therapy + temozolomide or radiation therapy only was given in 63 % and 26 %, respectively. The thirty-day mortality rate was 3 %. Median OS was 19 months (95 % CI 11–27 months). Age≥65 years, KPS<70, biopsy as opposed to resection, and no adjuvant treatment were confirmed negative prognostic factors in multivariate analysis. For patients undergoing resection, presence of postoperative contrast-enhanced tumor, not volume of residual tumor, had significant impact on OS in adjusted analysis.

Conclusions Median OS following surgery was 19 months, though much variable outcome was observed among subgroups of AA (95 % CI 11–27 months). Age ≥65 years, KPS<70, biopsy as opposed to resection, and no adjuvant treatment were confirmed negative prognostic factors for OS.

The behavior of residual tumors and facial nerve outcomes after incomplete excision of vestibular schwannomas

 incomplete excision of vestibular schwannomas

J Neurosurg 120:1278–1287, 2014

The authors evaluated the behavior of residual tumors and facial nerve outcomes after incomplete excision of vestibular schwannomas (VSs).

Methods. The case records of all patients who underwent surgical treatment of VSs were analyzed. All patients in whom an incomplete excision had been performed were analyzed. Incomplete excision was defined as near-total resection (NTR), subtotal resection (STR), and partial resection (PR). Tumors in the NTR and STR categories were followed up with a wait-and-rescan approach, whereas the tumors in the PR category were subjected to a second- stage surgery and were excluded from this series. All patients included in the study underwent baseline MRI at the 3rd and 12th postoperative months, and repeat imaging was subsequently performed every year for 7–10 years postoperatively or as indicated clinically. Preoperative and postoperative facial function was noted.

Results. Of the 2368 patients who underwent surgery for VS, 111 patients who had incomplete excisions of VSs were included in the study. Of these patients, 73 (65.77%) had undergone NTR and 38 (34.23%) had undergone STR. Of the VSs, 62 (55.86%) were cystic and 44 (70.97%) of these cystic VSs underwent NTR. The residual tumor was left behind on the facial nerve alone in 62 patients (55.86%), on the facial nerve and vessels in 2 patients (1.80%), on the facial nerve and brainstem in 15 patients (13.51%), and on the brainstem alone in 25 patients (22.52%). In the 105 patients with normal preoperative facial nerve function, postoperative facial nerve function was House-Brackmann (HB) Grades I and II in 51 patients (48.57%), HB Grade III in 34 patients (32.38%), and HB Grades IV–VI in 20 pa- tients (19.05%). Seven patients (6.3%) showed evidence of tumor regrowth on follow-up MRI. All 7 patients (100%) who showed evidence of tumor regrowth had undergone STR. No patient in the NTR group exhibited regrowth. The Kaplan-Meier plot demonstrated a 5-year tumor regrowth-free survival of 92%, with a mean disease-free interval of 140 months (95% CI 127–151 months). The follow-up period ranged from 12 to 156 months (mean 45.4 months).

Conclusions. The authors’ report and review of the literature show that there is undoubtedly merit for NTR and STR for preservation of the facial nerve. On the basis of this they propose an algorithm for the management of incomplete VS excisions. Patients who undergo incomplete excisions must be subjected to follow-up MRI for a period of at least 7–10 years. When compared with STR, NTR via an enlarged translabyrinthine approach has shown to have a lower rate of regrowth of residual tumor, while having almost the same result in terms of facial nerve function.

 

 

Surgery in lumbar degenerative spondylolisthesis: indications, outcomes and complications. A systematic review

Lumbar spondylolisthesis

Eur Spine J (2014) 23:945–973

This systematic review summarises the literature on patient selection, decision-making, effectiveness and outcomes in the surgical treatment of lumbar degenerative spondylolisthesis (LDS). Introduction In daily practice, decision-making in the treatment of LDS is challenging. There is little consensus on either the precise indications or prognostic factors for any specific therapy (operative or non-operative).

Methods We searched for LDS trials published between 01.01.1990 and 16.11.2011 in Medline, Embase, Cochrane Library and Cinahl. Two independent reviewers selected studies according to the inclusion criteria. Data were then extracted by two of the authors. Quality assessment was performed using the Downs and Black list for the clinical trials/studies and AMSTAR for the reviews. Results Data synthesis: 21 papers met the inclusion criteria (2 studies comprising both a RCT and a concurrent observational analysis, 1 RCT, 6 prospective studies, 8 retrospective studies, 3 reviews, 1 review guideline). The quality of the clinical studies was on average ‘‘fair’’ [mean score 15.6 points (range 10–19) out of 24 points (Downs and Black)]. The quality of the reviews ranged from 1 to 7 out of 11 points with an average of 5 points (AMSTAR). The study outcomes could not be subject to meta-analysis due to heterogeneity of study design and variable measure used.

Conclusions Despite there being many articles describing and/or comparing different surgical options for LDS, there was insufficient evidence to draw conclusions concerning clear indications for specific types of surgical treatment, predictors of outcome or complication rates. There remains a need to establish a decision-making tool to facilitate daily clinical practice and to assure appropriate treatment for patients with LDS.

Spinal juvenile (Type III) extradural-intradural arteriovenous malformations

Spinal extradural-intradural AVMs

 J Neurosurg Spine 20:452–458, 2014

Owing to their rarity, demographics, natural history, and treatment, results for spinal juvenile (Type III) extradural-intradural arteriovenous malformations (AVMs) are frequently only provided in case report format.

Methods. A pooled analysis was performed utilizing the PubMed database through April 2013. Individualized patient data were extracted to elucidate demographics, hemorrhage risk, and treatment result information.

Results. Twenty-nine studies describing 51 patients were included. The mean age at presentation was 15.0 ± 10.5 years with a slight male predilection (63%, 1.7:1 sex ratio). Presentation modality included progressive deficits in 35%, hemorrhage in 31%, acute deficits not attributed to hemorrhage in 22%, and asymptomatic/incidental in 12% of patients. The annual hemorrhage rate was 2.1%; statistically significant risk factors for hemorrhage included presentation age (HR 0.39 [95% CI 0.18–0.87]) and associated aneurysms (HR 8.74 [95% CI 1.76–43.31]). Seventy-seven percent of patients underwent treatment; after a mean follow-up of 2.6 ± 3.2 years, 73% were improved, 10% were the same, and 17% were worse neurologically. Of 25 cases with described angiographic results, 8 lesions were obliterated (32%). Of these 25 patients, 8 had AVMs with associated aneurysms, and the aneurysm was obliterated in all 8 patients. Over the course of 57.9 patient-years of follow-up, including 55.3 patient-years for partially treated AVMs, no hemorrhages were described, reflecting a trend toward protection from hemorrhage after treatment (p = 0.12, likelihood ratio test).

Conclusions. Spinal juvenile (Type III) extradural-intradural AVMs commonly present symptomatically. Associated arterial aneurysms increase their hemorrhage risk, and protection from hemorrhage may be achieved from partial obliteration of these lesions, particularly if targeted toward associated aneurysms.

Temporal Lobe Arteriovenous Malformations: Surgical Outcomes With a Focus on Visual Field Defects and Epilepsy

Temporal lobe AVM

Neurosurgery 73:854–862, 2013

Temporal lobe arteriovenous malformations (AVMs) represent a subgroup of intracranial AVMs with particular characteristics and management issues.

OBJECTIVE: To characterize the surgical outcomes of temporal lobe AVMs with emphasis on visual field deficits (VFDs) and seizures.

METHODS: Between 1992 and 2008, 29 patients were operated on for temporal lobe AVMs. Patient data were retrospectively collected and analyzed.

RESULTS: Twelve of 29 patients (41.4%) presented with seizures and 4 (13.7%) presented with VFDs. Postoperatively, 6 patients (24%) showed new VFDs and 2 improved, with a rate of preservation of full visual fields of 84%. Larger AVMs (.3 cm) were significantly associated with postoperative VFD (P = .008). Epilepsy outcomes assessed by the Engel scale were as follows: 9 patients (75%) were in class I (seizure free), 1 patient (8.3%) was in class III, and 2 patients (16.6%) were in class IV (no change or worsening). Postoperative modified Rankin Scale outcomes were excellent (grade 0-1) in 18 patients, good (grade 2) in 7, and poor (grade 3-4) in 4. Older age at diagnosis correlated with a worse functional outcome (Spearman r = 0.369; P = .049). AVMs were totally removed in 27 of 29 patients (93.1%). Complete surgical excision was confirmed with angiography. Two patients needed reoperation for AVM remnant. Three patients had persistent hemiparesis (10.3% permanent morbidity). There was no mortality.

CONCLUSION: Seizure control is usually underappreciated in the surgical management of AVMs. However, in temporal lobe AVMs, good outcomes with low morbidity and good visual field preservation can be accomplished.