Crossing the Cervicothoracic Junction During Posterior Cervical Decompression and Fusion: Is It Necessary?

BACKGROUND: Posterior cervical fusion (PCF) is performed to treat cervical myelopathy, radiculopathy, and/or deformity. Constructs ending at the cervicothoracic junction (CTJ) may lead to higher rates of adjacent segment disease, and much debate exists regarding crossing the CTJ due to paucity of data in the literature. OBJECTIVE: To determine whether extension of PCF constructs across the CTJ decreases incidence of adjacent segment disease and need for revision surgery. METHODS: A single-center retrospective case series of patients undergoing multilevel PCFs since 2011 with at least 6-mo follow-up was conducted. Outcomes were analyzed and compared based on caudal extent of instrumentation via multivariate regression. RESULTS: A total of 149 patients underwent PCF, with a mean follow-up of 18.9 mo. A total of 15 (10.1%) revisions were performed, 7 (4.7%) of which were related to the construct. Five (8.3%) revisions were performed for constructs ending at C6, 1 (5.3%) at C7, 1 (2.6%) at T1, and none (0%) at T2 (P = .035). Mean procedure duration was 215 min at C6, 214 min at C7, 239 min at T1, and 343 min at T2 (P = .001). Mean estimated blood loss was 224 mL at C6, 178 mL at C7, 308 mL at T1, and 575 mL at T2 (P = .001). There was no difference in length of stay, disposition, surgical site infection, or radiographic parameters. CONCLUSION: Extension of PCFs across the CTJ leads to lower early revision rates, but also to increased procedure duration and estimated blood loss. As such, decisions regarding caudal extent of instrumentation must weigh the risk of pseudarthrosis against that of longer procedures with higher blood loss.

What is the value of third-line chemotherapy in advanced gastroesophageal cancer? A 5-year retrospective analysis at a single center.

AIM: The survival benefit of using a non-cross resistant second-line chemotherapy in the third-line setting in metastatic gastroesophageal cancer is unproven. We evaluated the utility of third-line chemotherapy in patients treated at a single institution. METHODS: Between 2010 and 2014, efficacy and toxicity data of patients who received three or more lines of systemic therapies for metastatic gastroesophageal adenocarcinoma at the National Cancer Centre Singapore was retrospectively analyzed. RESULTS: Thirty-two (6%) patients received three or more lines of chemotherapy. The median age and ECOG performance status were 59 years (36-82) and 1 (0-2), respectively. Majority of patients (88%) had tumor located in the stomach and 13 patients (41%) had diffuse histology or poorly cohesive or signet ring cells. Four (12%) patients had HER2-positive disease. Prior therapy was platinum (100%), fluoropyrimidine (97%), taxane (63%), irinotecan (28%), anthracycline (13%) and ramucirumab (3%). Third-line therapy consisted of 24 (75%) monotherapy, 6 (19%) doublet, 1 (3%) triplet chemotherapy and 1 (3%) clinical trial. Monotherapy irinotecan (44%) was most common, followed by docetaxel (19%) and paclitaxel (9%). Of 22 patients evaluable for response, there was 1 (5%) partial response, 9 (41%) stable disease. Median overall survival was 18.3 weeks (4.3-65.1). Of 30 patients evaluable for toxicities, 17 (57%) experienced at least one grade 3 or 4 toxicities. CONCLUSION: The benefit of using non-cross resistant second-line regimens as third-line chemotherapy was small with moderate toxicity. Newer agents such as nivolumab or TAS-102 or clinical trial may be preferred.

Template-based B1 inhomogeneity correction in 3T MRI brain studies.

Low noise, high resolution, fast and accurate T1 maps from MRI images of the brain can be performed using a dual flip angle method. However, B1 field inhomogeneity, which is particularly problematic at high field strengths (e.g., 3T), limits the ability of the scanner to deliver the prescribed flip angle, introducing errors into the T1 maps that limit the accuracy of quantitative analyses based on those maps. A dual repetition time method was used for acquiring a B1 map to correct that inhomogeneity. Additional inaccuracies due to misregistration of the acquired T1-weighted images were corrected by rigid registration, and the effects of misalignment on the T1 maps were compared to those of B1 inhomogeneity in 19 normal subjects. However, since B1 map acquisition takes up precious scanning time and most retrospective studies do not have B1 map, we designed a template-based correction strategy. B1 maps from different subjects were aligned using a twelve-parameter affine registration. Recomputed T1 maps showed an important improvement with respect to the noncorrected maps: histograms of all corrected maps exhibited two peaks corresponding to white and gray matter tissues, while unimodal histograms were observed in all uncorrected maps because of the inhomogeneity. A method to detect the best nonsubject-specific B1 correction based on a set of features was designed. The optimum set of weighting factors for those features was computed. The best available B1 correction was detected in almost all subjects while corrections comparable to the T1 map corrected using the B1 map from the same subject were detected in the others.

Normal regional fractional anisotropy and apparent diffusion coefficient of the brain measured on a 3 T MR scanner.

INTRODUCTION: We aim to establish norms of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in 20 different regions of the brain in healthy human volunteers. METHODS: Thirty-one individuals were examined for ADC and FA in 20 regions of the brain using a single-shot, spin echo, echo planar diffusion tensor imaging sequence with 32 directions at 3 T. FA and ADC maps were computed using the Philips PRIDE tool, and regions of interest were drawn at 20 different locations in the brain. Relationships of FA and ADC with age and gender were explored. RESULTS: We found a negative correlation between age and FA in the inferior fronto-occipital fasciculus and forceps minor. There were no gender differences. The cerebral peduncle, the middle cerebellum, and cingulum had the highest variation in FA, while fornix, optic radiation, and optic tract had the highest variation in ADC. CONCLUSION: We provide a table of normative FA and ADC measurements in 20 brain regions of potential clinical relevance to the diagnosis and monitoring of specific neurological diseases.