Hyung-Youl Park, Young-Hoon Kim, Sang-Il Kim, Sung-Bin Han and Kee-Yong Ha
Few studies have addressed that dynamic sagittal imbalance can develop distal to the spinal fusion and cause sagittal malalignment, unlike proximal junctional kyphosis (PJK) in the proximal portion. The purpose of this study was to investigate risk factors between the 2 different types of postoperative sagittal imbalance after long fusion to the sacrum for the treatment of degenerative sagittal imbalance (DSI).
Eighty patients who had undergone surgical correction for DSI were included. Radiographic measurements included spinopelvic parameters on whole-spine plain radiographs and degeneration of paravertebral muscles on MRI. Univariate and multivariate analyses for clinical and radiological factors were conducted for respective risk factors. In subgroup analyses, the 2 different types of postoperative sagittal imbalance were directly compared.
Forty patients (50%) developed postoperative sagittal imbalance; of these patients, 22 (55.0%) developed static proximal kyphosis from PJK, and 18 patients (45.0%) developed dynamic sagittal imbalance without PJK. The independent risk factors in proximal kyphosis were greater postoperative pelvic tilt (HR 1.11) and less change in sacral slope (SS) (HR 1.09), whereas there were more fusion levels (HR 3.11), less change in SS (HR 1.28), and less change in thoracic kyphosis (HR 1.26) in dynamic sagittal imbalance. Directly compared with the proximal kyphosis group, dynamic sagittal imbalance was more commonly found in patients who had less correction of sagittal parameters as well as fatty atrophy of the paravertebral muscles. Clinical outcomes in the dynamic sagittal imbalance group were superior to those in the proximal kyphosis group.
Optimal correction of sagittal alignment should be considered in long instrumented fusion for DSI, because insufficient correction might cause one of 2 different types of postoperative sagittal imbalance at different sites of decompression. Dynamic sagittal imbalance compared with proximal kyphosis was significantly associated with less correction of sagittal alignment, in conjunction with more fusion levels and degeneration of the paravertebral muscles.
Eun Jung Lee, Jeong Hoon Kim, Eun Suk Park, Young-Hoon Kim, Jae Koo Lee, Seok Ho Hong, Young Hyun Cho and Chang Jin Kim
Advances in neuroimaging techniques have led to the increased detection of asymptomatic intracranial meningiomas (IMs). Despite several studies on the natural history of IMs, a comprehensive evaluation method for estimating the growth potential of these tumors, based on the relative weight of each risk factor, has not been developed. The aim of this study was to develop a weighted scoring system that estimates the risk of rapid tumor growth to aid treatment decision making.
The authors performed a retrospective analysis of 232 patients with presumed IM who had been prospectively followed up in the absence of treatment from 1997 to 2013. Tumor volume was measured by imaging at each follow-up visit, and the growth rate was determined by regression analysis. Predictors of rapid tumor growth (defined as ≥ 2 cm3/year) were identified using a logistic regression model; each factor was awarded a score based on its own coefficient value. The probability (P) of rapid tumor growth was estimated using the following formula:
Fifty-nine tumors (25.4%) showed rapid growth. Tumor size (OR per cm3 1.07, p = 0.000), absence of calcification (OR 3.87, p = 0.004), peritumoral edema (OR 2.74, p = 0.025), and hyperintense or isointense signal on T2-weighted MRI (OR 3.76, p = 0.049) were predictors of tumor growth rate. In the Asan Intracranial Meningioma Scoring System (AIMSS), tumor size was categorized into 3 groups of < 2.5 cm, ≥ 2.5 to < 4.0 cm, and ≥ 4.0 cm in diameter and awarded a score of 0, 3, and 6, respectively; the parameters of calcification and peritumoral edema were categorized into 2 groups based on their presence or absence and given a score of 0 or 2 and 1 or 0, respectively; and the signal on T2-weighted MRI was categorized into 2 groups of hypointense and hyperintense/isointense and given a score of 0 or 2, respectively. The risk of rapid tumor growth was estimated to be < 10% when the total score was 0–2, 10%–50% when the total score was 3–6, and ≥ 50% when the total score was 7–11 (Hosmer-Lemeshow goodness-of-fit test, p = 0.9958). The area under the receiver operating characteristic curve was 0.86.
The authors suggest a weighted scoring system (AIMSS) that predicts the specific probability of rapid tumor growth for patients with untreated IM. This scoring system will aid treatment decision making in clinical settings by screening out patients at high risk for rapid tumor growth.
Young-Hoon Kim, Young Jin Lee, Jung Ho Han, Soyeon Ahn, Jaebong Lee, Jae Hyoung Kim, Byung Se Choi, Jae Seung Bang, Chae-Yong Kim, Gyojun Hwang, O-Ki Kwon and Chang Wan Oh
The authors aimed to assess whether the prevalence of intracranial aneurysms in patients with intracranial meningiomas was higher than that in a healthy population.
The authors performed a hospital-based case-control study of 300 patients with newly diagnosed intracranial meningiomas and 900 age- and sex-matched controls without a history of brain tumors to evaluate any associations between intracranial aneurysms and intracranial meningiomas. Unconditional multivariate logistic regression models were used for case-control comparisons.
Intracranial aneurysms were identified in 23 patients (7.7%) and 24 controls (2.7%; p < 0.001). There was a significant association between intracranial aneurysms and intracranial meningiomas (OR 2.913, 95% CI 1.613–5.261) and hypertension (OR 1.905, 95% CI 1.053–3.446). In a subgroup analysis of the patients with newly diagnosed intracranial meningiomas, there was a significant association between intracranial aneurysms and hypertension (OR 2.876, 95% CI 1.125–7.352) and tumor volume (OR 1.012, 95% CI 1.001–1.024). These patients were also more likely than controls to have other intracranial vascular diseases (p < 0.001), such as isolated occlusion of the intracranial vessels, excluding intracranial aneurysms.
The prevalence of intracranial aneurysms was higher in patients with intracranial meningiomas. Hypertension and tumor volume appear to be associated with the formation of intracranial aneurysms in these patients.
Il-Nam Son, Young-Hoon Kim and Kee-Yong Ha
This retrospective study was designed to evaluate the clinical outcomes and radiological findings after open lumbar discectomy (OLD) in patients who were followed up for 10 years or longer.
The authors classified 79 patients who had a mean age (± SD) of 53.6 ± 13.6 years (range 30–78 years) into 4 groups according to the length of their follow-up. Patients in Group 1 were followed up for 10–14 years, in Group 2 for 15–19 years, in Group 3 for 20–24 years, and in Group 4 for more than 25 years. In all of these patients, the clinical outcomes were assessed by using patients' self-reported scores on visual analog scales (VASs) measuring back and leg pain and by using scores from the Oswestry Disability Index (ODI). In addition, 10 radiological parameters suggesting degenerative changes or instability at the operated segment were recorded at various time points and used to calculate a numeric radiological finding (NRF) score by rating a presence for each finding of spinal degeneration or instability as 1.
The authors observed that OLD decreased pain and disability scores in all groups. Numeric radiological findings were highest in Group 4, and a significant correlation was detected between NRFs and VAS scores of back pain (p = 0.039). In this cohort, the reoperation rate was 13.9% during a mean follow-up period of 15.3 years. Clinical outcomes tended to be most favorable in Group 1, representing patients who had OLD most recently, and they tended to deteriorate in the other 3 groups, indicating some worsening of outcomes over time. Degeneration of the spine at the operated level measured with radiographic methods tended to increase over time, but some stabilization was observed. Although spinal degeneration was stable, clinical outcomes deteriorated over time.
This cross-sectional assessment of a retrospective cohort indicates that outcomes after OLD deteriorate over time. Increased back pain indicated a worsening of clinical outcomes, and this worsening was correlated with radiological findings of degeneration at the operated segment.