bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does the Severity of the Curve in Lenke 1 and 2 Adolescent Idiopathic Scoliosis Patients Affect the Distance and Position of the Aorta From Vertebra?
Authors: Chiu Chee Kidd , Lee Keong Joo , Chung Weng Hong , Chandren Josephine Rebecca , Chan Chris Yin Wei , Kwan Mun Keong 
Published: November 2018

Study Design.
Retrospective study of a prospectively-collected data.

Objective.
To determine whether the severity of the curve magnitude in Lenke 1 and 2 Adolescent Idiopathic Scoliosis (AIS) patients affects the distance and position of the aorta from the vertebra.

Summary of Background Data.
There were studies that looked into the position of the aorta in scoliotic patients but none of them documented the change in distance of the aorta to the vertebra in relation to the magnitude of the scoliosis.

Methods.
Patients with Lenke 1 and 2 AIS who underwent posterior spinal fusion using pedicle screw construct and had a preoperative computed tomography (CT) scan performed were recruited. The radiological parameters measured on preoperative CT scan were: Aortic-Vertebral Distance (AVD), Entry-Aortic Distance (EAD), Aortic-Vertebral angle (AVA), Pedicle Aorta angle/Aortic Alpha angle (α angle), and Aortic Beta angle (β angle).

Results.
Thirty-nine patients were recruited. Significant moderate to strong positive correlation was found between AVD and Cobb angle from T8 to T12 vertebrae (r = 0.360 to 0.666). The EAD was generally small in the thoracic region (T4–T10) with mean EAD of less than 30 mm. Among all apical vertebrae, the mean AVD was 5.9 ± 2.2 mm with significant moderate-strong positive correlation to Cobb angle (r = 0.580). The mean α angle was 37.7 ± 8.7° with significant weak positive correlation with Cobb angle (r = 0.325).

Conclusion.
The larger the scoliotic curve, the aorta was located further away from the apical vertebral wall. The aorta has less risk of injury from the left lateral pedicle screw breach in larger scoliotic curve at the apical region. The distance from the pedicle screw entry point to the wall of the aorta was generally small (less than 30 mm) in the thoracic region (T4–T10).

Level of Evidence: 4
Effect of Modified Japanese Orthopedic Association Severity Classifications on Satisfaction With Outcomes 12 Months After Elective Surgery for Cervical Spine Myelopathy
Authors: Asher Anthony L. , Devin Clinton J. , Weisenthal Benjamin M. , Pennings Jacquelyn , Khan Inamullah , Archer Kristin R. , Sivaganesan Ahilan , Chotai Silky , Bydon Mohamad , Nian Hui , Harrell Frank E. , McGirt Matthew J. , Mummaneni Praveen , Bisson Erica F. , Shaffrey Christopher , Foley Kevin T. 
Published: November 2018

Study Design.
This study retrospectively analyzes prospectively collected data.

Objective.
Here, we aim to determine the influence of preoperative and 12-month modified Japanese Orthopedic Association (mJOA) on satisfaction and understand the change in mJOA severity classification after surgical management of degenerative cervical myelopathy (DCM).

Summary of Background Data.
DCM is a progressive degenerative spine disease resulting from cervical cord compression. The natural progression of DCM is variable; some patients experience periods of stability, while others rapidly deteriorate following disease onset. The mJOA is commonly used to grade and categorize myelopathy symptoms, but its association with postoperative satisfaction has not been previously explored.

Methods.
The quality and outcomes database (QOD) was queried for patients undergoing elective surgery for DCM. Patients were divided into mild (≥14), moderate (9 to 13), or severe (<9) categories on the mJOA scores. A McNemar–Bowker test was used to assess whether a significant proportion of patients changed mJOA category between preoperative and 12 months postoperative. A multivariable proportional odds ordinal logistic regression model was fitted with 12-month satisfaction as the outcome of interest.

Results.
We identified 1963 patients who underwent elective surgery for DCM and completed 12-months follow-ups. Comparing mJOA severity level preoperatively and at 12 months revealed that 55% remained in the same category, 37% improved, and 7% moved to a worse category. After adjusting for baseline and surgery-specific variables, the 12-month mJOA category had the highest impact on patient satisfaction (P < 0.001).

Conclusion.
Patient satisfaction is an indispensable tool for measuring quality of care after spine surgery. In this sample, 12-month mJOA category, regardless of preop mJOA, was significantly correlated with satisfaction. Given these findings, it is important to advise patients of the probability that surgery will change their mJOA severity classification and the changes required to achieve postoperative satisfaction.

Level of Evidence: 3
The Association Between Preoperative MRI Findings and Surgical Revision Within Three Years After Surgery for Lumbar Disc Herniation
Authors: Ziegler Dorthe Schoeler , Carreon Leah , Andersen Mikkel Oesterheden , Jensen Rikke Krüger 
Published: November 2018

Study Design.
This cohort study was an analysis of prospectively collected data in the DaneSpine Database.

Objective.
The objective was to determine whether preoperative magnetic resonance imaging (MRI) findings were associated with the frequency of surgical revision due to recurrent lumbar disc herniation (LDH) within 3 years after first-time, single-level, simple lumbar discectomy.

Summary of Background Data.
Because of a risk of poorer outcome in patients receiving revision surgery compared with first-time discectomy, there is a need to identify patients with LDH in risk of surgical revision prior to the primary discectomy. The association between preoperative MRI findings and revision surgery in patients with LDH has not been thoroughly studied.

Methods.
Following an interobserver reliability study preoperative MRIs were evaluated. Potential predictive variables for surgical revision were evaluated using univariate and multivariate logistic regression analysis. Also, a sum-score of the number of MRI findings at the involved level was assessed.

Results.
In a study population of 451 operated patients, those who had surgical revision were significantly younger and were significantly less likely to have vertebral endplate signal changes Type 2 (OR 0.36 (95% CI 0.15–0.88)) or more than five MRI findings (OR 0.45 (95% CI 0.21–0.95)) at the involved level than the patients not undergoing surgical revision. Surgical revision was not significantly associated with any other MRI findings.

Conclusions.
In general, preoperative MRI findings have a limited explanatory value in predicting surgical revision within 3 years after first-time, single-level, simple lumbar discectomy. Both the single variable VESC Type 2 and a sum-score > 5 MRI findings at the operated level were found to be negatively associated with patients undergoing surgical revision.

Level of evidence: 3
Comparison of Single-Level Versus Multilevel Vertebral Column Resection Surgery for Pediatric Patients With Severe Spinal Deformities
Authors: Hwang Chang Ju , Lenke Lawrence G. , Sides Brenda A. , Blanke Kathy M. , Kelly Michael P. 
Published: November 2018

Study Design.
Retrospective cohort of pediatric patients (younger than 21 years) with severe spinal deformities who underwent vertebral column resection (VCR) surgery.

Objective.
To compare patients who underwent single- versus multilevel VCR surgery in terms of radiographic correction and perioperative complications.

Summary of Background Data.
There are few studies comparing single- to multilevel VCR surgery regarding the efficacy and safety of the procedures.

Methods.
Eighty-two pediatric patients who underwent a VCR for severe spinal deformity between 2002 and 2012 by one surgeon were included. A single-level VCR was performed in 45 patients with an average of 4.7-year follow-up, and multilevel VCR in 37 patients with an average of 4.6-year follow-up.

Results.
Coronal Cobb corrections were not different between groups (single level: 63%, multilevel: 58%, P = 0.146). Correction loss at final follow-up did not differ (3.1° vs. 0.3°, P = 0.132). Patients in the single-level group had shorter operation times (9.2 vs. 10.5 hours, P = 0.046), whereas estimated blood loss did not differ between the two groups (1061 vs. 1200 mL, P = 0.181). The rate of spinal cord monitoring events was 20% (8/40) and 30% (9/30), respectively. No patient in the single-level group had a postoperative neurologic deficit, whereas three patients in the multilevel group experienced a temporary deficit postoperatively (0/45 vs. 3/37, P = 0.088).

Conclusion.
There was no difference in radiographic correction between the single- and multilevel VCR groups. The multilevel VCR patients had longer operative times, and although the differences were not statistically significant due to low sample size, the multilevel VCR group also had an increased rate of postoperative neurologic deficits. We would recommend single-level VCRs unless there is an absolute indication for multilevel resection as in necessary decompression for spinal cord impingement.

Level of Evidence: 4
Efficiency of Power Versus Hand Screwdriver for Cortical Lag Screw Insertion
Authors: Runner Robert P. , Boissonneault Adam R. , Bellamy J. Taylor , Moore Thomas J. 
Published: November 2018

Introduction:
Limited studies exist on which modality, power or manual instruments, is superior for cortical screw placement. More efficient screw insertion could decrease operative time and reduce overall cost. The purpose of this study is to compare the speed and accuracy of lag screw placement in sawbone models using power and manual screwdrivers.

Materials and Methods:
A total of 48 orthopedic faculty, orthopedic residents, and medical students participated. Eight stations were tested, each with a different anatomic location (femur/tibia/radius), trajectory (anterior-posterior, lateral-medial, oblique), and screw length (18 to 95 mm). Each station had 1 correct passage and 4 false passages to assess for accuracy. The time required to place the screw in the correct passage using both power and hand screwdrivers was recorded along with the total attempts.

Results:
There was no significant difference in speed or accuracy of screw placement using power or manual screwdrivers. However, more accurate screw placement was significantly associated with faster insertion time. Level of training and attendance of a basic fracture course were significantly associated with faster insertion times and more accurate insertion when using the power screwdriver on certain stations, but there was no difference using the manual screwdriver.

Conclusions:
The difference in time between the actual techniques of using power or manual tools is marginal as accuracy is the most important factor for screw insertion efficiency. We propose that surgeons utilize the modality they are more accurate with to prevent misdirected screws and increase efficiency in the operating room.
Circumferential Pharyngoesophageal Reconstruction and Total Larynx Preservation with Extra-anatomical Free Flaps
Authors: Lasso Jose M. , Castellano Michele , Pinilla Carmen , González-Pozega Carlota , Pérez-Cano Rosa 
Published: November 2018

Summary:
Reconstruction of total circumferential pharyngeal defects following caustic or stenosant lesions of the pharynx present major challenges with respect to minimizing surgical morbidity and restoring functional deficits. With recent advances in microvascular free tissue transfer, the options for pharyngeal reconstruction have multiplied in order to maximize swallowing and voice. There is long experience in the reconstruction of the pharynx and the cervical esophagus in oncological patients after total pharyngolaryngectomy, but there are not many publications concerning circumferential pharyngeal reconstruction preserving the larynx. Here, we discuss 2 new techniques for total circumferential pharyngeal reconstruction respecting swallowing and voice by means of extra-anatomical bypasses (visceral or fasciocutaneous), upholding the larynx in its original placement.
The Effect of Liposuction Cannula Diameter on Fat Retention—Based on a Rheological Simulation
Authors: Tong Yuanren , Liu Penghao , Wang Yuneng , Geng Chang , Han Xuefeng , Ma Jiguang , Li Facheng , Cai Lei 
Published: November 2018

Background:
Autologous fat is considered as an ideal material for soft-tissue augmentation in plastic and reconstructive surgery. The primary drawback of autologous fat grafting is the high absorption rate, thus fat retention is considered as an essential indicator. There are several researches about the factors that can influence fat retention, including centrifugation and cannula size. However, rheological models of cannula during liposuction are limited. This research focuses on the effects of cannulas with diameters of 2 mm and 2.5 mm on fat retention, which is based on a rheological simulation of inlet pressure and maximum velocity. Experiments on mice were also conducted to confirm the result from the simulation.

Methods:
A simulation was conducted with the physical parameters of the adipose tissue. Human lipoaspirate samples were obtained from patients by liposuction through cannulas of different diameters and were transferred into subcutaneous tissue of nude mice, a part of which were used in viscosity and density measurement. Graft retention was measured and fat quality was assessed through histologic analysis after 6 months.

Results:
Viscosity and density of the fat tissue had significant effects on fat retention. The 2.5 mm diameter cannula had significantly lower inlet pressure and maximum velocity and thus led to higher graft retention, but oil cystic nodules appeared meanwhile.

Conclusions:
Cannulas with larger diameters have lower inlet pressure and maximum velocity during the liposuction process, which further influences the viability of adipocytes and adipose stem cells and thus has larger fat graft retention. This research built a mathematical model with less bias than in vivo experiments and provides a general way for analyzing the outcome of a liposuction precisely, which adds to the data for cannula optimization.
THE OCCURRENCE, CHARACTERISTICS, MANAGEMENT, AND PROGNOSIS OF RETINAL PIGMENT EPITHELIUM TEARS IN PATIENTS WITH POLYPOIDAL CHOROIDAL VASCULOPATHY
Authors: Zhao Xin-yu , Xia Song , Luo Ming-yue , Wang Er-qian , Chen You-xin 
Published: November 2018

Purpose:
To investigate retinal pigment epithelium (RPE) tears in patients with polypoidal choroidal vasculopathy.

Method:
A retrospective review of polypoidal choroidal vasculopathy cases with confirmed RPE tears was conducted. Patients' comprehensive clinical data were collected and analyzed. The treatment strategy was a loading dose of one intravitreal antivascular endothelial growth factor injection, combined with additional injections if exudative activities or visual deterioration were detected.

Results:
Among 397 polypoidal choroidal vasculopathy patients, 33 patients with RPE tears (8.3%) were included. 42.4% of them happened spontaneously. Pigment epithelial detachment (PED) occurred more frequently in RPE tear patients and most of them had serous vascularized or hemorrhagic PED. The height and greatest linear diameter of PED, and the subfoveal choroidal thickness of these cases were significantly larger, whereas the central foveal thickness was significantly smaller. Most of the RPE tears occurred at the edge of the PED. After our treatment strategy, patients' best-corrected visual acuity improved significantly from 2.13 ± 1.24 (median 20/52) to 1.32 ± 1.31 (median 20/166). Large subretinal hemorrhage may increase the risk of the formation of subretinal fibrosis (P < 0.05).

Conclusion:
Retinal pigment epithelium tears in polypoidal choroidal vasculopathy are associated with high subRPE hydrostatic pressure, produced by a large PED or hemorrhage. After our intervention strategy, this condition may not necessarily result in poor prognosis.
ADVERSE EVENTS OF THE ARGUS II RETINAL PROSTHESIS
Authors: Rizzo Stanislao , Barale Pierre-Olivier , Ayello-Scheer Sarah , Devenyi Robert G. , Delyfer Marie-Noëlle , Korobelnik Jean-François , Rachitskaya Aleksandra , Yuan Alex , Jayasundera K. Thiran , Zacks David N. , Handa James T. , Montezuma Sandra R. , Koozekanani Dara , Stanga Paulo E. , da Cruz Lyndon , Walter Peter , Augustin Albert J. , Chizzolini Marzio , Olmos de Koo Lisa C. , Ho Allen C. , Kirchhof Bernd , Hahn Paul , Vajzovic Lejla , Iezzi Raymond , Gaucher David , Arevalo J. Fernando , Gregori Ninel Z. , Grisanti Salvatore , Özmert Emin , Yoon Young Hee , Kokame Gregg T. , Lim Jennifer I. , Szurman Peter , de Juan Eugene , Rezende Flavio A. , Salzmann Joël , Richard Gisbert , Huang Suber S. , Merlini Francesco , Patel Uday , Cruz Cynthia , Greenberg Robert J. , Justus Sally , Cinelli Laura , Humayun Mark S. 
Published: November 2018

Purpose:
To analyze and provide an overview of the incidence, management, and prevention of conjunctival erosion in Argus II clinical trial subjects and postapproval patients.

Methods:
This retrospective analysis followed the results of 274 patients treated with the Argus II Retinal Prosthesis System between June 2007 and November 2017, including 30 subjects from the US and European clinical trials, and 244 patients in the postapproval phase. Results were gathered for incidence of a serious adverse event, incidence of conjunctival erosion, occurrence sites, rates of erosion, and erosion timing.

Results:
Overall, 60% of subjects in the clinical trial subjects versus 83% of patients in the postapproval phase did not experience device- or surgery-related serious adverse events. In the postapproval phase, conjunctival erosion had an incidence rate of 6.2% over 5 years and 11 months. In 55% of conjunctival erosion cases, erosion occurred in the inferotemporal quadrant, 25% in the superotemporal quadrant, and 20% in both. Sixty percent of the erosion events occurred in the first 15 months after implantation, and 85% within the first 2.5 years.

Conclusion:
Reducing occurrence of conjunctival erosion in patients with the Argus II Retinal Prosthesis requires identification and minimization of risk factors before and during implantation. Implementing inverted sutures at the implant tabs, use of graft material at these locations as well as Mersilene rather than nylon sutures, and accurate Tenon's and conjunctiva closure are recommended for consideration in all patients.
Clinical Presentation and Management Outcomes of Coexistent Congenital Glaucoma and Retinopathy of Prematurity
Authors: Senthil Sirisha , Balijepalli Pasyanthi , Garudadri Chandrasekhar , Jalali Subhadra 
Published: November 2018

Purpose:
The purpose of this study was to report presentation and outcomes of coexisting congenital glaucoma with retinopathy of prematurity (ROP) in “Indian Twin cities ROP study (ITCROPS).”

Methods:
Children with ROP and congenital glaucoma were identified from ITCROPS (prospective digital database) between 1997 and 2016. The presentation, interventions, and outcomes for glaucoma and ROP were evaluated.

Results:
Out of 15,000 premature-infants database, 3000 children had ROP, of these 87 eyes of 64 premature children had glaucoma. Five eyes (5.7%) of 3 children in the entire ROP cohort had coexisting congenital glaucoma (before any ROP intervention), 3 eyes of 2 children had primary congenital glaucoma and 2 eyes of one child had glaucoma with microspherophakia. The mean age at surgery was 2.7±0.6 months. At presentation, all eyes had corneal edema, mean corneal diameter was 10.3±0.75 mm and IOP was 20.4±1.67 mm Hg. Three eyes had stage-2 ROP and two eyes had stage-3 ROP. Four eyes received intravitreal Bevacizumab. All eyes underwent combined trabeculotomy with trabeculectomy. Post glaucoma surgery, 2 eyes underwent laser for ROP and 1 eye with stage-2 ROP was observed with no treatment. ROP regressed without any sequalae in all 5 eyes. Two eyes with microspherophakia and one eye with lens coloboma underwent lensectomy. One eye postlensectomy needed Ahmed glaucoma valve implant for IOP control. The mean IOP at last follow-up was 13.6±1.67 mm Hg and all eyes needed topical antiglaucoma medications for IOP control.

Conclusions:
Congenital glaucoma coexisting with ROP is a medical emergency. Intravitreal therapy can help tide over the vision-threatening fulminant phase of ROP while awaiting the effect of glaucoma surgery on corneal clarity. The need for medications even after glaucoma surgery suggests severe glaucoma phenotype. Close coordination between subspecialties is needed for best outcomes.
Optical Coherence Tomography Angiography of Optic Disc and Macula Vessel Density in Glaucoma and Healthy Eyes
Authors: Yip Vivien C.H. , Wong Hon Tym , Yong Vernon K.Y. , Lim Boon Ang , Hee Owen K. , Cheng Jun , Fu Huazhu , Lim Chingwei , Tay Elton L.T. , Loo-Valdez Roselyn G. , Teo Hwei Yee , Lim PH Angela , Yip Leonard W.L. 
Published: November 2018

Aim:
To study the microvascular density of the macular and optic nerve head in healthy and glaucoma subjects using optical coherence tomography angiography.

Methodology:
We performed a cross-sectional cohort study on healthy subjects and patients with glaucoma. The AngioVue Enhanced Microvascular Imaging System was used to capture the optic nerve head and macula images during one visit. En face segment images of the macular and optic disc were studied in layers. Microvascular density of the optic nerve head and macula were quantified by the number of pixels measured by a novel in-house developed software. Areas under the receiver operating characteristic curves (AUROC) were used to determine the accuracy of differentiating between glaucoma and healthy subjects.

Results:
A total of 24 (32 eyes) glaucoma subjects (57.5±9.5-y old) and 29 (58 eyes) age-matched controls (51.17±13.5-y old) were recruited. Optic disc and macula scans were performed showing a greater mean vessel density (VD) in healthy compared with glaucoma subjects. The control group had higher VD than the glaucoma group at the en face segmented layers of the optic disc (optic nerve head: 0.209±0.05 vs. 0.110±0.048, P<0.001; vitreoretinal interface: 0.086±0.045 vs. 0.052±0.034, P=0.001; radial peripapillary capillary: 0.146±0.040 vs. 0.053±0.036, P<0.001; and choroid: 0.228±0.074 vs. 0.165±0.062, P<0.001). Similarly, the VD at the macula was also greater in controls than glaucoma patients (superficial retina capillary plexus: 0.115±0.016 vs. 0.088±0.027, P<0.001; deep retina capillary plexus: 0.233±0.027 vs. 0.136±0.073, P<0.001; outer retinal capillary plexus: 0.190±0.057 vs. 0.136±0.105, P=0.036; and choriocapillaris: 0.225±0.053 vs. 0.153±0.068, P<0.001. The AUROC was highest for optic disc radial peripapillary capillary (0.96), followed by nerve head (0.92) and optic disc choroid (0.76). At the macula, the AUROC was highest for deep retina (0.86), followed by choroid (0.84), superficial retina (0.81), and outer retina (0.72).

Conclusions:
Microvascular density of the optic disc and macula in glaucoma patients was reduced compared with healthy controls. VD of both optic disc and macula had a high diagnostic ability in differentiating healthy and glaucoma eyes.