Comparing the effectiveness of full-vacuum and half-vacuum drainage in reducing seroma after modified radical mastectomy: a meta-analysis.

INTRODUCTION: Owing to limited outpatient support for drain management, delayed discharge after mastectomy is more prevalent in developing countries. Utilising half-vacuum (HV) suction drains for routine drainage after mastectomy could lead to a reduced incidence of seroma and a shorter hospital stay. This systematic review and meta-analysis compared the outcomes of HV against full-vacuum (FV) suction drains in patients who underwent modified radical mastectomy for breast cancer. METHODS: Differences between the two groups in length of hospital stay, total volume of drain effluent and incidence of seroma were assessed. RevMan 5.4 was used to calculate the odds ratio (OR) and relative risk (RR) for dichotomous data, and the mean difference (MD) for continuous data. RESULTS: Nine randomised controlled trials were included in this review. Using HV drains reduced both the mean length of hospital stay (MD: -2.30 days, 95% confidence interval [CI]: -4.10 to -0.49 days, I2=97%) and the mean total volume of effluent (MD: -132.61ml, 95% CI: -207.32ml to -57.91ml, I2=88%) compared with FV drains. However, there was no statistically significant difference in incidence of seroma between the two groups (RR: 0.67, 95% CI: 0.30 to 1.46, I2=65%). Likewise, there was no difference in rate of seroma occurrence on sensitivity analysis (OR: 1.29, 95% CI: 0.72 to 2.33, I2=74%). CONCLUSIONS: There was no difference in the incidence of seroma between HV and FV suction drainage. Conversely, a reduction in the length of hospital stay and the total volume of drain effluent was observed for mastectomy patients with a HV drain.

Evaluating the complications of adult groin hernia where there is no hernia registry: a systematic review of Nigerian literature.

BACKGROUND: Enumerating the complications of groin hernia repair might help to highlight the need for improvement in the quality of care. This is imperative in a country without a strong post-operative complication surveillance mechanism. Hence, this review aims to determine the complications encountered during the surgical treatment of groin hernias among Nigerian subjects. METHODS: Databases like Google Scholar, Scopus, and PubMed were searched. Out of the 140 papers found during the search, only 20 were included in this review. Bassini repair was the most common type of hernia repair used, and neither laparoscopic repair nor posterior approach was utilized in any of the patients. Emergency presentations constituted about 18.5% of the cases. Meta-analysis of the studies showed that more prevalent complications were wound/scrotal edema (derived from four studies), surgical site infections (derived from 17 studies), and hematoma (from 19 studies). The rates were 23% (CI 0-46%; I2 = 80.9%), 6% (CI 3-10%; I2 = 87.7%), and 5% (CI 2-8%; I2 = 83.7%), respectively. The rate of complication in giant hernias was higher than the non-giant hernias and was statistically significant [p < 0.05; OR 1.5 (CI 0.9-2.4)]. Although the recurrence rate is low, there was insufficient follow-up of patients. CONCLUSION: This review has shown that one-fifth of the patients had emergency repair of hernias and giant groin hernias have higher odds of complications after repair compared to normal-sized ones. The most common complication noted was wound/scrotal edema. None of the hernias was repaired with laparoscopy. Perhaps, establishing a registry might improve the detection of late complications in patients who had groin hernia repair.

Evaluation of localization uncertainty of fiducial markers due to length and position variations induced by motion in CT imaging by measurement and modeling.

PURPOSE: To quantify the variations in the length and position of fiducial markers induced by motion in axial (ACT), helical (HCT) and cone-beam CT (CBCT) imaging and associated uncertainty in image-guided radiotherapy (IGRT) by measurement and modeling. METHODS: A mobile thorax phantom containing markers of various lengths was imaged using ACT, HCT and CBCT imaging. The phantom was imaged while stationary and moving where it was moved sinusoidally with different motion amplitudes and frequency. An analytical motion model was developed that predicts the localization accuracy of IGRT based on fiducial markers in mobile phantom with ACT, HCT and CBCT. RESULTS: The apparent lengths of the markers varied with the different motion patterns and CT imaging modalities. In CBCT, the apparent length of the markers increased linearly with the motion amplitude for both half-fan and full-fan modes. In HCT and ACT, the apparent length of the markers increased or decreased non-linearly with motion parameters and speed of the imaging couch. When the marker moved opposed to couch motion the apparent lengths decreased, while they increased when the phantom moved along the direction of the imaging couch as predicted by the motion model. The position of marker centers did not shift and distance between makers did not change in CBCT images. However, in HCT and ACT, the position of marker center and distance between markers varied depending on motion parameters during imaging. The marker center could move superiorly or inferiorly and the distance between markers could increase or decrease depending on the phase of motion as predicted by the motion model. CONCLUSIONS: The variations of marker length and position due to phantom motion were quantified by measurement and modeling. These variations may lead to large positioning uncertainties in patient setup and tumor localization based on IGRT with fiducial marker registration.

SU-E-T-520: Quantitative Evaluation of Metal Artifacts in CT and Cone-Beam CT Images on the Accuracy of Dose Calculation.

PURPOSE: To investigate effects of metal artifacts on the dose calculation accuracy of three dose calculation algorithms on CT and cone-beam CT images. METHODS: A phantom with and without metal objects was scanned using CT simulator and on-board kV CBCT. Conformal 5-field treatment plans with identical physical and dosimetric parameters were created in the Eclipse™ treatment planning system for CT and CBCT images. The beams were designed to avoid entering through metallic object. Three dose calculation algorithms were used in the plans: (a) pencil beam convolution with modified Batheo (PBC-MB), (b) equivalent TAR (PBC-ET), and (c) analytical anisotropic algorithm (AAA). The dose calculation on the phantom CT images without metal was used as reference to compare with doses calculated using scans with metal objects. The gamma analysis and percentage dose differences were used to quantify the dosimetric effects of image artifacts from metal on CT and CBCT numbers. RESULTS: The dose difference analysis shows that mean percentage dose differences (MPDD) for CBCT with metal artifacts ranged from -0.12% to -0.26% with an average of -0.20% for PBC-MB, -0.25% to -0.39%, with average -0.31% for PBC-ET, and -0.25 to -0.84%, with average -0.62% for AAA for all planes. The PBC-MB showed the least difference in dose and highest gamma passing rates with the AAA consistently having the highest differences and lowest gamma passing rates. This might result from accurate consideration of scattered dose in heterogeneities by AAA. All MPDD for doses calculated on CT and CBCT using different dose calculation algorithms were not significant (within 1%). CONCLUSION: The image artifacts due to streaking from metal objects were generally small (within 1%) for the dose calculated using the different treatment planning algorithms on CT and CBCT images. Furthermore, the dose difference from CT-number variation between CBCT and CT were negligible.

SU-E-J-02: Accuracy of Fiducial Marker Localization Using Axial and Helical CT, Cone-Beam CT and KV Imaging.

PURPOSE: To determine localization errors of fiducial markers using axial (ACT) and helical CT (HCT), cone beam CT (CBCT) and kV imaging. METHODS AND MATERIALS: A thorax phantom containing markers of various sizes (2.5, 5, 10, 20mm) was imaged using ACT, HCT, CBCT and kV imaging. The phantom was imaged with and without motion (15mm amplitude, 15 cycles/min). CT images were reconstructed at 0.625, 1.25, 2.5 and 5mm thickness. Marker location and length were measured using axial and coronal imaging. RESULTS: The measured marker size increased almost linearly with increased slice thickness used in CT reconstruction with ACT for the stationary phantom. In HCT, the marker size varied non-linearly with increase in slice thickness. Motion of the phantom induced further blurring and shifts of the center of the marker with different sizes. The 10 mm marker was elongated up to 13.5 mm and 16.2 mm in the ACT and HCT, respectively. The markers were elongated up to nearly 26 mm using axial and helical scanning modes by phantom motion. The displacement of maker center was more prominent in the HCT with a shift up to 2 mm due to slice thickness for stationary phantom. The marker center was displaced by up to 18 and 22 mm using ACT and HCT, respectively, which was even higher than 15 mm motion amplitude. KV imaging produced the sharpest marker image with the least difference between actual and measured marker sizes. CONCLUSION: Increase in slice thickness enlarged the apparent marker size and displaced the maker center in ACT and HCT. Motion led to further enlargement in the maker size and displacement of maker center that depended on the motion amplitude. These effects should be considered in CT-based image-guided radiation therapy to ensure accurate tumor localization and patient positioning with implanted markers.