Category: Statistics

ERJ Open Res. 2023 Oct 16;9(5):00091-2023. doi: 10.1183/23120541.00091-2023. eCollection 2023 Sep.

ABSTRACT

BACKGROUND: Chylothorax is an uncommon medical condition for which limited data are available regarding the contemporary aetiology, management and outcomes. The goal of this study was to better define these poorly characterised features.

METHODS: The medical records of adult patients diagnosed with chylothorax at 12 centres across Europe, America and South Africa from 2009-2021 were retrospectively reviewed. Descriptive and inferential statistics were performed.

RESULTS: 77 patients (median age 69 years, male to female ratio 1.5) were included. Subacute dyspnoea was the most typical presenting symptom (66%). The commonest cause of chylothorax was malignancy (68.8%), with lymphoma accounting for 62% of these cases. Other aetiologies were trauma (13%), inflammatory/miscellaneous conditions (11.7%) and idiopathic cases (6.5%). At the initial thoracentesis, the pleural fluid appeared milky in 73%, was exudative in 89% and exhibited triglyceride concentrations >100 mg·dL^-1 in 88%. Lymphangiography/lymphoscintigraphy were rarely ordered (3%), and demonstration of chylomicrons in pleural fluid was never ascertained. 67% of patients required interventional pleural procedures. Dietary measures were infrequently followed (36%). No patient underwent thoracic duct ligation or embolisation. Morbidity included infections (18%), and thrombosis in malignant aetiologies (16%). The 1-year mortality was 47%. Pleural fluid protein >3.5 mg·dL^-1 (sub-distribution hazard ratio (SHR) 4.346) or lactate dehydrogenase <500 U·L^-1 (SHR 10.21) increased the likelihood of effusion resolution. Pleural fluid protein ≤3.5 mg·dL^-1 (HR 4.047), bilateral effusions (HR 2.749) and a history of respiratory disease (HR 2.428) negatively influenced survival.

CONCLUSION: Chylothoraces have a poor prognosis and most require pleural interventions. Despite the standard recommendations, lymphatic imaging is seldom used, nor are dietary restrictions followed.

PMID:37850216 | PMC:PMC10577597 | DOI:10.1183/23120541.00091-2023

Plast Reconstr Surg Glob Open. 2023 Oct 16;11(10):e5342. doi: 10.1097/GOX.0000000000005342. eCollection 2023 Oct.

ABSTRACT

BACKGROUND: Abdominoplasty techniques are well documented. The ideal position of the umbilicus has, however, received limited attention. Unfortunately, umbilicus position is not universally agreed upon in male cosmetic abdominoplasty. This study was conducted to determine the ideal umbilicus anthropometric measurements in young men, and the relationships between umbilical position and anterior trunk and torso reference points that may be applicable to intraoperative positioning. It is aimed also at investigating whether umbilicus position would be more accurately determined by considering nipple position instead of the abdominal crease, as recently proposed.

METHODS: Several anthropometric measurements of various anterior abdominal and thoracic landmarks were conducted on 60 young and middle-aged male volunteers and 30 cadavers at São Paulo city. All statistical analysis was completed using Stata software.

RESULTS: Of all the measured reference points, a much stronger correlation (0.513) was demonstrated between umbilicus-anterior axillary fold (U-AX) and inter-nipple (N-N) distances with a constant golden number ratio relationship (N-N = U-AX × 0.618) compared with the weak correlation of 0.034 between umbilicus-xiphisternum and umbilicus-abdominal crease. In 75% of volunteers, the calculated U-AX was within ±3 cm of actual measurement, and in 33.33% within ±1 cm.

CONCLUSIONS: U-AX = 1.618 × N-N equation is more predictive of adequate umbilicus repositioning during abdominoplasty in male patients. Chest and abdomen of men are a single aesthetic unit. Proper positioning of the nipples and umbilicus, as well as harmonious abdominal and torso proportions are critical for an optimal final aesthetic outcome.

PMID:37850205 | PMC:PMC10578692 | DOI:10.1097/GOX.0000000000005342

Plast Reconstr Surg Glob Open. 2023 Oct 16;11(10):e5353. doi: 10.1097/GOX.0000000000005353. eCollection 2023 Oct.

ABSTRACT

Infections are problematic in postmastectomy implant-based reconstruction with infection rates as high as 30%. Strategies to reduce the risk of infection have demonstrated various efficacies. A prolonged course of systemic, oral antibiotics has not shown evidence-based benefit. Although absorbable antibiotic beads have been described for orthopedic procedures and pressure wounds, their use has not been well studied during breast reconstruction, particularly for prepectoral implant placement. The purpose of this study was to evaluate the selective use of prophylactic absorbable calcium sulfate antibiotic beads during high-risk implant-based, prepectoral breast reconstruction after mastectomy. Patients who underwent implant-based, prepectoral breast reconstruction between 2019 and 2022 were reviewed. Groups were divided into those who received antibiotic beads and those who did not. Outcome variables included postoperative infection at 90 days. A total of 148 patients (256 implants) were included: 15 patients (31 implants) who received biodegradable antibiotic beads and 133 patients (225 implants) in the control group. Patients who received antibiotic beads were more likely to have a history of infection (66.7%) compared with the control group (0%) (P < 0.01). Surgical site infection occurred in 3.2% of implants in the antibiotic bead group compared with 7.6%, but this did not reach statistical significance. The incidence of infection in high-risk patients who have absorbable antibiotic beads placed during the time of reconstruction seems to be normalized to the control group in this pilot study. We present a novel use of prophylactic absorbable antibiotic beads in prepectoral breast implant reconstruction.

PMID:37850203 | PMC:PMC10578659 | DOI:10.1097/GOX.0000000000005353

Plast Reconstr Surg Glob Open. 2023 Oct 16;11(10):e5358. doi: 10.1097/GOX.0000000000005358. eCollection 2023 Oct.

ABSTRACT

BACKGROUND: Research is a valued component of applications to plastic surgery residency. No prior studies have explored factors associated with increased resident research productivity. This study aims to compare the academic productivity levels of plastic surgery residency graduates based on their pre- and postresidency experiences.

METHODS: Residents graduating in 2019 and 2020 were identified from integrated programs. Metrics collected included the number of publications in medical school and residency. Descriptive statistics were completed along with linear regressions to evaluate the impact of these on academic productivity.

RESULTS: A total of 221 residents from the classes of 2019 and 2020 were included. Most residents completed fellowship (75.9%) although less than half went on to academic practice (42.3%). Approximately one in five residents obtained secondary degrees (17.4%). Subjects averaged 3.15 (N = 208, SD = 4.51) publications while in medical school and 8.1 publications during residency (N = 209, SD = 10.0). For h-index calculated at the end of residency, having dedicated medical school research time was the only statistically significant factor (coefficient = 2.96, P = 0.002).

CONCLUSIONS: Plastic surgery residents published more often as first authors and overall during residency than medical school, indicating increased research involvement and leadership. The present study builds upon prior studies by confirming the importance of dedicated medical school research time and its lasting impact. Understanding the associations of academic factors with increased research productivity in residency is relevant for both applicants and programs evaluating residency candidates.

PMID:37850201 | PMC:PMC10578684 | DOI:10.1097/GOX.0000000000005358

Plast Reconstr Surg Glob Open. 2023 Oct 16;11(10):e5346. doi: 10.1097/GOX.0000000000005346. eCollection 2023 Oct.

ABSTRACT

BACKGROUND: There is a growing societal trend in plastic surgery patients of viewing their medical care as a commodity product rather than as a healthcare service. Our four-provider private plastic surgery practice noticed this phenomenon through our patients’ trend of overusing the emergency after-hours service call line. To affect this behavior, we designed a study educating patients on the emergency service call line’s purpose and how to handle nonurgent issues independently.

METHODS: After a 6-month preintervention phase to categorize after-hours emergency calls, We improved preoperative patient education and implemented in-office protocols for quicker provider responses. Postintervention data were collected for another 6 months and compared statistically with the preintervention data.

RESULTS: In the preinterventional period, we saw a total of 236 after-hours phone calls. The intervention led to a 22% significant reduction in total calls (P = 0.007). Calls were categorized as nonurgent, urgent, and emergent. While emergent calls remained unchanged (P = 0.56), nonurgent calls significantly decreased (P = 0.005). The most common nonurgent calls were regarding pain, routine postoperative concerns, and drain care, with the intervention resulting in a significant reduction of routine postoperative swelling/bruising/discomfort calls (P = 0.04) but not changing pain (P = 0.23) or drain-related calls (P = 0.78).

CONCLUSIONS: We found that targeted preoperative patient education coupled with a real-time action board in the office, to ensure timely response to patient questions during office hours, can positively impact after-hours call use, and improve overall patient outcomes by catching urgent issues earlier.

PMID:37850200 | PMC:PMC10578723 | DOI:10.1097/GOX.0000000000005346

BME Front. 2022 Apr 4;2022:9793716. doi: 10.34133/2022/9793716. eCollection 2022.

ABSTRACT

Objective and Impact Statement. This study developed and validated a deep semantic segmentation feature-based radiomics (DSFR) model based on preoperative contrast-enhanced computed tomography (CECT) combined with clinical information to predict early recurrence (ER) of single hepatocellular carcinoma (HCC) after curative resection. ER prediction is of great significance to the therapeutic decision-making and surveillance strategy of HCC. Introduction. ER prediction is important for HCC. However, it cannot currently be adequately determined. Methods. Totally, 208 patients with single HCC after curative resection were retrospectively recruited into a model-development cohort ($n=180$) and an independent validation cohort ($n=28$). DSFR models based on different CT phases were developed. The optimal DSFR model was incorporated with clinical information to establish a DSFR-C model. An integrated nomogram based on the Cox regression was established. The DSFR signature was used to stratify high- and low-risk ER groups. Results. A portal phase-based DSFR model was selected as the optimal model (area under receiver operating characteristic curve (AUC): development cohort, 0.740; validation cohort, 0.717). The DSFR-C model achieved AUCs of 0.782 and 0.744 in the development and validation cohorts, respectively. In the development and validation cohorts, the integrated nomogram achieved C-index of 0.748 and 0.741 and time-dependent AUCs of 0.823 and 0.822, respectively, for recurrence-free survival (RFS) prediction. The RFS difference between the risk groups was statistically significant ($P<0.0001$ and $P=0.045$ in the development and validation cohorts, respectively). Conclusion. CECT-based DSFR can predict ER in single HCC after curative resection, and its combination with clinical information further improved the performance for ER prediction.

PMID:37850181 | PMC:PMC10521680 | DOI:10.34133/2022/9793716

BME Front. 2022 Jul 1;2022:9794321. doi: 10.34133/2022/9794321. eCollection 2022.

ABSTRACT

Objective. Initial performance evaluation of a system for simultaneous high-resolution ultrasound imaging and focused mechanical submillimeter histotripsy ablation in rat brains. Impact Statement. This study used a novel combination of high-resolution imaging and histotripsy in an endoscopic form. This would provide neurosurgeons with unprecedented accuracy in targeting and executing nonthermal ablations in minimally invasive surgeries. Introduction. Histotripsy is a safe and effective nonthermal focused ablation technique. However, neurosurgical applications, such as brain tumor ablation, are difficult due to the presence of the skull. Current devices are too large to use in the minimally invasive approaches surgeons prefer. We have developed a combined imaging and histotripsy endoscope to provide neurosurgeons with a new tool for this application. Methods. The histotripsy component had a 10 mm diameter, operating at 6.3 MHz. Affixed within a cutout hole in its center was a 30 MHz ultrasound imaging array. This coregistered pair was used to ablate brain tissue of anesthetized rats while imaging. Histological sections were examined, and qualitative descriptions of ablations and basic shape descriptive statistics were generated. Results. Complete ablations with submillimeter area were produced in seconds, including with a moving device. Ablation progress could be monitored in real time using power Doppler imaging, and B-mode was effective for monitoring post-ablation bleeding. Collateral damage was minimal, with a 100 μm maximum distance of cellular damage from the ablation margin. Conclusion. The results demonstrate a promising hardware suite to enable precision ablations in endoscopic procedures or fundamental preclinical research in histotripsy, neuroscience, and cancer.

PMID:37850178 | PMC:PMC10521722 | DOI:10.34133/2022/9794321

BME Front. 2022 Oct 25;2022:9786242. doi: 10.34133/2022/9786242. eCollection 2022.

ABSTRACT

The immunohistochemical (IHC) staining of the human epidermal growth factor receptor 2 (HER2) biomarker is widely practiced in breast tissue analysis, preclinical studies, and diagnostic decisions, guiding cancer treatment and investigation of pathogenesis. HER2 staining demands laborious tissue treatment and chemical processing performed by a histotechnologist, which typically takes one day to prepare in a laboratory, increasing analysis time and associated costs. Here, we describe a deep learning-based virtual HER2 IHC staining method using a conditional generative adversarial network that is trained to rapidly transform autofluorescence microscopic images of unlabeled/label-free breast tissue sections into bright-field equivalent microscopic images, matching the standard HER2 IHC staining that is chemically performed on the same tissue sections. The efficacy of this virtual HER2 staining framework was demonstrated by quantitative analysis, in which three board-certified breast pathologists blindly graded the HER2 scores of virtually stained and immunohistochemically stained HER2 whole slide images (WSIs) to reveal that the HER2 scores determined by inspecting virtual IHC images are as accurate as their immunohistochemically stained counterparts. A second quantitative blinded study performed by the same diagnosticians further revealed that the virtually stained HER2 images exhibit a comparable staining quality in the level of nuclear detail, membrane clearness, and absence of staining artifacts with respect to their immunohistochemically stained counterparts. This virtual HER2 staining framework bypasses the costly, laborious, and time-consuming IHC staining procedures in laboratory and can be extended to other types of biomarkers to accelerate the IHC tissue staining used in life sciences and biomedical workflow.

PMID:37850170 | PMC:PMC10521710 | DOI:10.34133/2022/9786242

BMC Res Notes. 2023 Oct 17;16(1):275. doi: 10.1186/s13104-023-06515-8.

ABSTRACT

OBJECTIVE: In epidemiological and experimental research, high folic acid intake has been demonstrated to accelerate tumor development among populations with genetic and/or molecular susceptibility to cancer. Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder predisposing affected individuals to tumorigenesis, including benign plexiform neurofibromas; however, understanding of factors associated with tumor risk in NF1 patients is limited. Therefore, we investigated whether pregestational folic acid intake modified plexiform-like peripheral nerve sheath tumor risk in a transgenic NF1 murine model.

RESULTS: We observed no significant differences in overall survival according to folate group. Relative to controls (180 days), median survival did not statistically differ in deficient (174 days, P = 0.56) or supplemented (177 days, P = 0.13) folate groups. Dietary folate intake was positively associated with RBC folate levels at weaning, (P = 0.023, 0.0096, and 0.0006 for deficient vs. control, control vs. supplemented, and deficient vs. supplemented groups, respectively). Dorsal root ganglia (DRG), brachial plexi, and sciatic nerves were assessed according to folate group. Mice in the folate deficient group had significantly more enlarged DRG relative to controls (P = 0.044), but no other groups statistically differed. No significant differences for brachial plexi or sciatic nerve enlargement were observed according to folate status.

PMID:37848948 | DOI:10.1186/s13104-023-06515-8

Harm Reduct J. 2023 Oct 17;20(1):150. doi: 10.1186/s12954-023-00888-6.

ABSTRACT

BACKGROUND: Recent policies have lessened restrictions around prescribing buprenorphine-naloxone (buprenorphine) for the treatment of opioid use disorder (OUD). The primary concern expressed by critics of these policies is the potential for buprenorphine diversion. However, the population-level effects of increased buprenorphine diversion are unclear. If replacing the use of heroin or fentanyl, use of diverted buprenorphine could be protective.

METHODS: Our study aim was to estimate the impact of buprenorphine diversion on opioid overdose using an agent-based model calibrated to North Carolina. We simulated the progression of opioid misuse and opioid-related outcomes over a 5-year period. Our status quo scenario assumed that 50% of those prescribed buprenorphine diverted at least one dose per week to other individuals with OUD and 10% of individuals with OUD used diverted buprenorphine at least once per week. A controlled prescription only scenario assumed that no buprenorphine would be diverted, while an increased diversion scenario assumed that 95% of those prescribed buprenorphine diverted and 50% of individuals with OUD used diverted buprenorphine. We assumed that use of diverted buprenorphine replaced the use of other opioids for that day. Sensitivity analyses increased the risk of overdose when using diverted buprenorphine, increased the frequency of diverted buprenorphine use, and simulated use of diverted buprenorphine by opioid-naïve individuals. Scenarios were compared on opioid overdose-related outcomes over the 5-year period.

RESULTS: Our status quo scenario predicted 10,658 (credible interval [CI]: 9699-11,679) fatal opioid overdoses. A scenario simulating controlled prescription only of buprenorphine (i.e., no diversion) resulted in 10,741 (9895-11,650) fatal opioid overdoses versus 10,301 (9439-11,244) within a scenario simulating increased diversion. Compared to the status quo, the controlled prescription only scenario resulted in a similar number of fatal overdoses, while the scenario with increased diversion of buprenorphine resulted in 357 (3.35%) fewer fatal overdoses. Even when increasing overdose risk while using diverted buprenorphine and incorporating use by opioid naïve individuals, increased diversion did not increase overdoses compared to a scenario with no buprenorphine diversion.

CONCLUSIONS: A similar number of opioid overdoses occurred under modeling conditions with increased rates of buprenorphine diversion among persons with OUD, with non-statistical trends toward lower opioid overdoses. These results support existing calls for low- to no-barrier access to buprenorphine for persons with OUD.

PMID:37848945 | DOI:10.1186/s12954-023-00888-6