Observed Length Increases of Magnetically Controlled Growing Rods are Lower Than Programmed.

BACKGROUND: Magnetically controlled growing rods (MCGRs) are increasingly used in the treatment of early onset scoliosis (EOS). Few studies have reported whether desired lengthening can reliably be achieved, or if prior spine instrumentation and large tissue depths affect lengthening. In this clinical study of EOS patients, it was hypothesized that increases in rod length would equal programmed increases, patients with prior spine instrumentation would lengthen less than patients without prior surgery, and larger tissue depths would decrease lengthening success. METHODS: A retrospective chart review was conducted on EOS patients with single and dual MCGRs placed between April 2014 to September 2015 and distracted at a single institution. Rod distraction was measured at each visit using ultrasound. Differences between programmed and actual distraction for each patient, and between groups with and without prior spine instrumentation, were determined by 2-tailed t tests. Regression and correlation were used to determine the relationship between tissue depth and length increases. RESULTS: Thirty-one patients were included, 18 males, 13 females, age 8.1 (±2.5) years, with major curves measuring 60 (±14.6) degrees at time of MCGR insertion. In the 12 patients with prior instrumentation, time from initial growing rod placement to MCGR insertion was 23.1 (±10.6) months. The number of surgical procedures before MCGR insertion was 2.8 (±2.0). Total length increase relative to the programmed distraction was 86% (±21) (P<0.001). Length increases for patients with and without prior surgery were 87% (±23) and 86% (±19), respectively (P>0.9). Total lengthening was inversely proportional to tissue depth (r=0.38, P<0.01); the decrease in lengthening achieved was 2.1%/mm of tissue depth. CONCLUSIONS: Increases in rod length were 14% lower than the programmed distraction. Prior instrumentation did not impact the amount of rod distraction. Greater distance between the rod and the skin surface negatively affected the magnitude of distraction.

Proton therapy posterior beam approach with pencil beam scanning for esophageal cancer : Clinical outcome, dosimetry, and feasibility.

PURPOSE: The aim of this study is to present the dosimetry, feasibility, and preliminary clinical results of a novel pencil beam scanning (PBS) posterior beam technique of proton treatment for esophageal cancer in the setting of trimodality therapy. METHODS: From February 2014 to June 2015, 13 patients with locally advanced esophageal cancer (T3-4N0-2M0; 11 adenocarcinoma, 2 squamous cell carcinoma) were treated with trimodality therapy (neoadjuvant chemoradiation followed by esophagectomy). Eight patients were treated with uniform scanning (US) and 5 patients were treated with a single posterior-anterior (PA) beam PBS technique with volumetric rescanning for motion mitigation. Comparison planning with PBS was performed using three plans: AP/PA beam arrangement; PA plus left posterior oblique (LPO) beams, and a single PA beam. Patient outcomes, including pathologic response and toxicity, were evaluated. RESULTS: All 13 patients completed chemoradiation to 50.4 Gy (relative biological effectiveness, RBE) and 12 patients underwent surgery. All 12 surgical patients had an R0 resection and pathologic complete response was seen in 25 %. Compared with AP/PA plans, PA plans have a lower mean heart (14.10 vs. 24.49 Gy, P < 0.01), mean stomach (22.95 vs. 31.33 Gy, P = 0.038), and mean liver dose (3.79 vs. 5.75 Gy, P = 0.004). Compared to the PA/LPO plan, the PA plan reduced the lung dose: mean lung dose (4.96 vs. 7.15 Gy, P = 0.020) and percentage volume of lung receiving 20 Gy (V20; 10 vs. 17 %, P < 0.01). CONCLUSION: Proton therapy with a single PA beam PBS technique for preoperative treatment of esophageal cancer appears safe and feasible.

Trending and accuracy of noninvasive hemoglobin monitoring in pediatric perioperative patients.

BACKGROUND: Rainbow Pulse CO-Oximetry technology (Masimo Corporation, Irvine, CA) provides continuous and noninvasive measurement of arterial hemoglobin concentration (SpHb). We assessed the trending and accuracy of SpHb by this innovative monitoring compared with Hb concentration obtained with conventional laboratory techniques (Hb) in children undergoing surgical procedures with potential for substantial blood loss. METHODS: Hb concentrations were recorded from Pulse CO-Oximetry and a conventional hematology analyzer. Regression analysis and 4-quadrant plot were used to evaluate the trending for changes in SpHb and Hb measurements (ΔSpHb and ΔHb). Bias, precision, and limits of agreement of SpHb and of in vivo adjusted SpHb (SpHb - first bias to HB) compared with Hb were calculated. RESULTS: One hundred fifty-eight SpHb-Hb data pairs and 105 delta pairs (ΔSpHb and ΔHb) from 46 patients aged 2 months to 17 years with Hb ranging from 16.7 to 7.9 g/dL were collected. To evaluate trending, the delta pairs (ΔSpHb and ΔHb) were plotted, which revealed a positive correlation (ΔSpHb = 0.022 + 0.76ΔHb) with correlation coefficient r = 0.76, 95% CI [confidence interval] = 0.57-0.86. The bias and precision of SpHb to Hb and in vivo adjusted SpHb were 0.4 ± 1.3 g/dL and 0.1 ± 1.2 g/dL, respectively; the limits of agreement were -2.0 to 3.2 g/dL before in vivo adjustment and -2.4 to 2.2 g/dL after in vivo adjustment (P value = 0.04). The mean percent bias (from the reference Hb concentration) decreased from 4.1% ± 11.9% to 0.7% ± 11.3% (P value = 0.01). No drift in bias over time was observed during the study procedure. Of patient demographic and physiological factors tested for correlation with the SpHb, only perfusion index at sensor site showed a weak correlation. CONCLUSIONS: The accuracy of SpHb in children with normal Hb and mild anemia is similar to that previously reported in adults and is independent of patient demographic and physiological states except for a weak correlation with perfusion index. The trending of SpHb and Hb in children with normal Hb and mild anemia showed a positive correlation. Further studies are necessary in children with moderate and severe anemia.

Growing Rod versus Posterior Spinal Fusion Treatment of Juvenile Idiopathic Scoliosis: Unique Characteristics and Surgical Outcomes.

Progressive spinal curvature in juvenile idiopathic scoliosis (JIS) is challenging to treat. When conservative management fails, treatments include growing rods (GRs) or posterior spinal fusion (PSF). The purpose of this study is to compare the patient characteristics and outcomes of GR and PSF treatment of JIS. We performed a retrospective review of demographic, radiographic, and surgical data for all JIS patients requiring surgical treatment between 2012 and 2020. Patients who underwent any GR treatment were compared to PSF patients. A total of 36 patients (13 GR, 23 PSF) were reviewed. PSF patients had a larger pre-operative spinal height (p = 0.002), but similar pre-operative major curve magnitudes (p = 0.558). PSF treatment resulted in similar change in the T1-S1 length (p = 0.002), but a greater correction of the curve magnitude (p < 0.055) compared to GR patients. Eight patients initially treated with GRs later underwent definitive PSF treatment. This subset of patients had a greater spinal height before PSF (p = 0.006), but similar immediate post-PSF T1-S1 lengths (p = 0.437) and smaller changes in spinal height from PSF (p = 0.020) than primary PSF patients. At final follow-up, patients who underwent primary PSF versus PSF after GR had similar spinal heights (p = 0.842). The surgical intervention chosen to manage progressive JIS often differs based on patient characteristics. While this choice may impact immediate outcomes, the outcomes at final follow up are similar.

Utilizing two surgeons for neuromuscular scoliosis suggests improved operative efficiency.

PURPOSE: Neuromuscular scoliosis (NMS) patients tend to have significant comorbidities with complex medical and surgical histories. When undergoing posterior spinal fusion (PSF), NMS risks can be much higher than the idiopathic population. This study aimed to identify the impact of two experienced pediatric cosurgeons (CS) compared to a single spine surgeon (SS) on the intra- and postoperative results of NMS PSF. METHODS: A database of NMS patients who had undergone PSF 2016-2021 identified 53 patients, of which 32 were CS, while 21 were SS. Patients' sex, age, weight, diagnosis, curve severity, fusion performed, estimated blood loss (EBL), transfusion rates, hemoglobin, anesthesia and surgical times, length of stay, and complications were collected. RESULTS: Patient demographics were similar between groups. Curves were more severe in the CS group (p = 0.013). Intraoperatively, CS patients underwent larger corrections (p = 0.089) but in significantly shorter anesthetic (p = 0.0018) and operative (p = 0.0025) times. Blood loss and transfusions were similar. Postoperatively, intensive-care unit (ICU) admission and length of stay (LOS) were similar, but SS had higher rates of both unplanned ICU admissions (p = 0.36) and 30 day readmissions (p = 0.053). Complications overall were similar between the groups both within 30 days (p = 0.40) and in the short-term period (31-90 days, p = 0.76), though the CS cohort had less Grade 2 immediate postoperative pulmonary complications (p = 0.16). CONCLUSION: Utilizing CS for NMS PSF has been found to reduce operative times. Downstream, additional potential impacts trended toward fewer unplanned ICU admissions, less-frequent postoperative pulmonary complications, and reduced 30-day readmission rates.