BACKGROUND: Women with unilateral breast cancer are at increased risk for having simultaneous cancer of the contralateral breast. Overall, earlier detection of contralateral breast cancer prevents the burden of additional surgery or chemotherapy rounds and is associated with higher overall survival. However, MRI screening for the contralateral breast is seldom done following an initial unilateral breast cancer diagnosis. The purpose of this study is to retrospectively evaluate patients with known, biopsy-proven malignancy who went on to obtain a breast MRI and were later found to have cancer of the contralateral breast.  Methods: This was a retrospective study that reviewed the charts of women aged over 18 years who were determined to have synchronous bilateral breast cancer from January 2017 to January 2022 at the University of Florida, Gainesville, FL. The study extracted data from this institution\'s cancer registry database, which provided information on patients with breast cancer diagnoses. The study conducted a review of mammography (MAM) and MRI imaging reports to ascertain the presence or absence of contralateral breast cancer identified by each respective imaging modality. Surgical pathology reports from the biopsy of the contralateral breast were reviewed to obtain information on the histological type of cancer and TNM (tumor, node, metastasis) staging.
RESULTS: Of the 17 cases in which MAM missed contralateral cancer, follow-up MRI detected contralateral malignancy in 12 cases (70.59%) and subsequently changed management, resulting in additional imaging, biopsy, and eventual diagnosis and treatment of contralateral breast cancer. Examining the number of contralateral breast cancers detected by patients who had undergone MAM followed by MRI and those who had only undergone MAM, the study found that the detection rate of contralateral breast cancer from MAM was 45.45% (15/33). The tumor stages of the missed cancers were all T1 or Tis stage with one T1mi, and there was no nodal involvement.  Conclusion: In addition to its utility in staging breast cancers, MRI also has the superior ability to detect otherwise undetected contralateral breast malignancy. This retrospective study found that MRI imaging led to a considerable increase in the detection of contralateral cancer. The study found that these undetected contralateral breast cancers by MAM were often of lower staging with no nodal involvement, highlighting the opportunity for MRI to assist in early cancer detection while the patient\'s prognosis is still good. Its high cost should be balanced with staging and occult malignancy detection utility in future practice.

BACKGROUND: An open wedge high tibial osteotomy (OWHTO) may lead to gait alteration, which change the contact loading in the contralateral knee, while clear evidence about the impact on contralateral knee still lacks. The purpose of the current study was to evaluate the change in scintigraphic uptake using SPECT-CT in the medial compartment of the contralateral knee following OWHTO.
METHODS: Contralateral radiographic measurements were performed for patients with medial osteoarthritis and varus malalignment of >5° treated with OWHTO in this retrospective analysis. The medial compartmental changes according to SPECT/CT analysis before and 1-year after OWHTO were evaluated on the contralateral side.
RESULTS: The study comprised 72 patients. The mean preoperative mechanical femorotibial angle was a mean varus of 7.6° (range, 5.1° - 13.0°), corrected to a mean valgus of 2.5° (range, 1.9° - -8.5°) postoperatively. The average grading of the scintigraphic uptakes in the medial compartment of the contralateral knee was significantly decreased 1 year postoperatively than after the surgery (from 2.8 ± 0.4 to 2.1 ± 0.6, p < 0.001). Measurable differences in varus alignment on radiographs of the contralateral limb were identified. The preoperative mechanical axis value decreased from 8.0° ± 2.4° to 6.7° ± 2.6° at the 3-month postoperative visit (p = 0.011). The overall decrease in varus alignment remained at the 2-year final postoperative follow-up.
CONCLUSIONS: Alignment correction by OWHTO results in reducing scintigraphy uptakes in medial compartment and improvement in mechanical alignment of the contralateral knee.
METHODS: Therapeutic Level IV.

OBJECTIVE: To determine the prevalence of occult contralateral nodal metastasis in tonsillar squamous cell carcinoma (TSCC) in patients who have undergone bilateral neck dissection.
METHODS: A systematic review of English articles identified from PubMed, Embase, and Web of Science databases.
METHODS: Search terms included \"oropharynx,\" \"carcinoma,\" \"lymph node,\" and \"neck dissection.\" Two reviewers independently screened abstracts, reviewed full texts, and extracted data from all studies that presented the prevalence of contralateral occult nodal metastasis in TSCC.
RESULTS: The overall prevalence of occult contralateral nodal metastasis was 10%. The prevalence was 8% for cT1/T2 tumors, 19% for cT3/T4, 1% for N0 in the ipsilateral neck, and 12% for N+. Occult contralateral lymph nodes were most frequently found in neck level II (81%) and level III (19%). No metastatic nodes were found in level I.
CONCLUSIONS: Elective neck dissection of the contralateral neck in TSCC is controversial due the historic morbidity caused by the surgery. A widely accepted recommendation suggests performing an elective neck dissection when the prevalence of occult metastasis is between 15% and 20%. The results of this study suggest that elective contralateral neck dissection will identify occult positivity in 19% of patients with T3/T4 tonsil cancer. In T1/T2 or N0 tumors, the diagnostic yield would be considerably lower at 8% and 1%, respectively. Contralateral nodal sampling could be considered based on patient preference after adequate counseling on the risks/benefits of occult nodal detection. More research is needed on other nodal features to formulate treatment guidelines. Laryngoscope, 2024.

Choroid plexus papilloma (CPP) is a rare benign intracranial tumor origin that predominantly manifests in the lateral ventricle in children, accounting for 0.3%-0.6% of all primary intracranial tumors. It is extremely rare to have the CPP in the trigone of the lateral ventricle through the contralateral posterior interhemispheric transfalcine transprecuneus approach (PITTA). Herein, we report this rare case. A 7-year-old girl presented with headache. Magnetic resonance imaging of the brain showed periatrial lesions, and histopathological examination confirmed CPP (WHO grade I). The contralateral PITTA is a safe, effective, reasonable, and appropriate for some lesions in the trigone of the lateral ventricle. It provides a wider surgical angle (especially for the lateral extension) and reduces the risk of disturbance of the optic radiation compared with the conventional approaches. The use of multiple modern neurosurgical techniques, including interventional embolization, intraoperative navigation, microscope, and electrophysiological monitoring, make the procedure much easier and more accurate, and the neuroendoscope adds to the visualization of the microscope and can reduce surgical complications.

We aimed to evaluate the effects of the antioxidant thymoquinone on treated and untreated kidneys on histological and oxidative parameters as well as Kidney Injury Molecule (KIM-1) levels in an experimental unilateral ureteropelvic junction obstruction (UPJO) with resultant hydronephrosis (HN) model. In adherence to the Animal research: reporting of in vivo exepriments guidelines, 34 male Wistar rats were randomly divided into four groups which were named accordingly: \"CO\" (corn oil), \"TQ\" (thymoquinone and corn oil), \"HNCO\" (UPJO-HN and corn oil), \"HNTQ\" (UPJO-HN, thymoquinone and corn oil). Histologically, pelvic epithelial damage, glomerular shrinkage and sclerosis, tubular damage, interstitial edema-inflammation-fibrosis (IEIF), and vascular congestion were assessed. Biochemically, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione reductase (GR) and KIM-1 levels were assessed. Macroscopic HN developed in all obstructed kidneys. Ipsilateral obstructed kidneys deteriorated in all histological parameters. Thymoquinone attenuated glomerular shrinkage and sclerosis alterations but increased vascular congestion. Contralateral non-obstructed kidneys also showed histological deterioration. Thymoquinone had beneficial effects in terms of IEIF presence in contralateral kidneys but it increased vascular congestion. MDA and SOD results were inconclusive. UPJO caused decreased GR levels in the ipsilateral kidneys but not in the contralateral ones. This effect was not ameliorated by thymoquinone treatment. KIM-1 levels were increased in ipsilateral obstructed kidneys with a lower level in HNTQ group than in HNCO. KIM-1 level of the ipsilateral HNTQ group was higher than in both non-obstructed ipsilateral kidney groups. The effect of thymoquinone in ameliorating bilaterally observed histological alterations was limited and controversial. Oxidative damage detected by GR measurements was not prevented by thymoquinone. Thymoquinone partially decreased the damage as evidenced by reduced KIM-1 levels in thymoquinone-treated obstructed kidneys.

BACKGROUND: Despite national guidelines against contralateral prophylactic mastectomy (CPM) in low- to moderate-risk breast cancer, CPM use continues to rise. Breast reconstruction improves health-related quality of life and satisfaction among women undergoing mastectomy. Given the lack of data regarding factors associated with reconstruction after CPM and the known benefits of reconstruction, we sought to investigate whether disparities exist in receipt of reconstruction after CPM.
METHODS: The 2004-2017 National Cancer Database was queried to identify women diagnosed with breast cancer who underwent unilateral mastectomy with CPM. Patients were divided into two groups: those who underwent planned reconstruction at any timepoint and those who did not. A secondary analysis comparing types of reconstruction (tissue, implant, combined) was conducted. Patient, tumor, and demographic characteristics were analyzed using chi-square test and odds ratios were calculated using generalized estimating equations.
RESULTS: The cohort included 1,73,249 women: 95,818 (55.3%) underwent reconstruction and 77,431 (45.7%) did not. Both the rate CPM and the proportion of women undergoing reconstruction after CPM increased between 2004 and 2017. Of the women who had reconstruction, 40,840 (51.7%) received implants, 29,807 (37.7%) had tissue, and 8352 (10.6%) had combined reconstruction. After adjusted analysis, factors associated with reconstruction were young age, Hispanic ethnicity, private insurance, and living in an area with the highest education and median income (P < 0.01). Patients who underwent reconstruction were less likely to have radiation (P < 0.01) and chemotherapy (P < 0.01), more likely to have stage I disease (P < 0.01), and to be treated at an integrated cancer center (P < 0.01).
CONCLUSIONS: Reconstruction after CPM is disproportionately received by younger women, Hispanics, those with private insurance, and higher socioeconomic status and education. While the rate of reconstruction after CPM is increasing, there remain significant disparities. Conscious efforts must be made to eliminate these disparities, especially given the known benefits of reconstruction after mastectomy.

Background: We aimed to investigate the extent of the response of the orbicularis oris muscle to stimulation of the contralateral facial nerve both in patients with peripheral facial palsy (PFP) and in healthy subjects. Methods: EMG was performed at 2-6 weeks after the onset of PFP in the patient group and at any time in the healthy control group. We performed nerve conduction testing, electroneurography, and surface and needle EMG. Results: A total of 276 participants (patients/healthy controls: 218/58) were analyzed. The extent of the response of the contralateral orbicularis oris muscles to facial nerve stimulation was higher in healthy controls compared to that in the affected group. The response of the contralateral orbicularis oris muscles to stimulation of the paralyzed facial nerve was more extensive in those patients to whom glucocorticoid or physical therapy had been given. Cross-facial innervation in the orbicularis oris muscle extended up to 1.5 cm in one-third of healthy controls and was higher than that in those with PFP. Glucocorticoid or physical therapy seemed to improve cross-innervation in facial palsy. Conclusions: Our findings suggest that the stimulus leading to the contralateral muscular response is mediated through crossing axons rather than muscular fibers.

BACKGROUND: World Health Organisation (WHO) and USA Centers for Disease Control and Prevention (U.S. CDC) recommendations now allow simultaneous administration of COVID-19 and other vaccines. We compared antibody responses after coadministration of influenza and bivalent COVID-19 vaccines in the same (ipsilateral) arm vs. different (contralateral) arms.
METHODS: Pre- and post-vaccination serum samples from individuals in the Prospective Assessment of COVID-19 in a Community (PACC) cohort were used to conduct haemaglutination inhibition (HI) assays with the viruses in the 2022-2023 seasonal influenza vaccine and focus reduction neutralisation tests (FRNT) using a BA.5 SARS-CoV-2 virus. The effect of ipsilateral vs. contralateral vaccination on immune responses was inferred in a model that accounted for higher variance in vaccine responses at lower pre-vaccination titers.
RESULTS: Ipsilateral vaccination did not cause higher influenza vaccine responses compared to contralateral vaccination. The response to SARS-CoV-2 was slightly increased in the ipsilateral group, but equivalence was not excluded.
CONCLUSIONS: Coadministration of influenza and bivalent COVID-19 vaccines in the same arm or different arms did not strongly influence the antibody response to either vaccine.
BACKGROUND: This work was supported by the U.S. CDC (grant number: 75D30120C09259).

To explore the preoperative high-risk clinical factors for contralateral medium-volume central lymph node metastasis (conMVCLNM) in unilateral papillary thyroid carcinoma (uPTC) and the indications for dissection of contralateral central lymph nodes (conCLN).
Clinical and pathological data of 204 uPTC patients who underwent thyroid surgery at the Hangzhou First People\'s Hospital from September 2010 to October 2022 were collected. Univariate and multivariate logistic regression analyses were conducted to determine the independent risk factors for contralateral central lymph node metastasis (conCLNM) and conMVCLNM in uPTC patients based on the preoperative clinical data. Predictive models for conCLNM and conMVCLNM were constructed using logistic regression analyses and validated using receiver operating characteristic (ROC) curves, concordance index (C-index), calibration curves, and decision curve analysis (DCA).
Univariate and multivariate logistic regression analyses showed that gender (P < 0.001), age (P < 0.001), tumor diameter (P < 0.001), and multifocality (P = 0.008) were independent risk factors for conCLNM in uPTC patients. Gender(P= 0.026), age (P = 0.010), platelet-to-lymphocyte ratio (PLR) (P =0.003), and tumor diameter (P = 0.036) were independent risk factors for conMVCLNM in uPTC patients. A predictive model was established to assess the risk of conCLNM and conMVCLNM, with ROC curve areas of 0.836 and 0.845, respectively. The C-index, the calibration curve, and DCA demonstrated that the model had good diagnostic value.
Gender, age, tumor diameter, and multifocality are high-risk factors for conCLNM in uPTC patients. Gender, age, tumor diameter, and PLR are high-risk factors for conMVCLNM in uPTC patients, and preventive conCLN dissection should be performed.

BACKGROUND: It is estimated that one-third of patients presenting with unilateral joint pain have contralateral osteoarthritis (OA) at first presentation. Most studies have primarily examined White patient cohorts. The purpose of this study was to determine the prevalence of contralateral joint OA for patients presenting for unilateral total knee (TKA), unicompartmental knee (UKA) or total hip arthroplasty (THA) among Asian, Native Hawaiian/Pacific Islander and White patients.
METHODS: Bilateral radiographic reports at initial presentation of 2,312 subjects who underwent unilateral arthroplasties (332 UKAs, 933 TKAs and 1,047 THAs) were reviewed. The presence of contralateral OA was recorded and compared by racial group and type of arthroplasty performed. Parametric statistical analyses were performed to determine differences between groups. Multivariable analyses were completed for each arthroplasty group to determine the influence on the presence of contralateral OA, presented as odds ratios and 95% confidence intervals.
RESULTS: Contralateral joint OA was present in 86.7%, 90.4% and 70.4% of UKA, TKA and THA patients, respectively. Concurrent hip OA was present in 41.6% and 59.5% of UKA and TKA patients. No racial differences in the prevalence of contralateral knee OA were found for knee arthroplasty patients. White patients (74.6%) had a greater prevalence of contralateral hip OA compared to Asians (66.5%, p = 0.037) amongst THA recipients. Increased age and body mass index were significantly associated with the presence of contralateral knee OA. Increased age, being male and being White were significant contributors for the presence of contralateral hip OA.
CONCLUSIONS: The prevalence of contralateral joint OA and concurrent hip OA is high in all three racial groups. Due to the extensive prevalence of contralateral and concurrent knee and hip OA, bilateral radiographic evaluation should be considered for all patients presenting with unilateral hip or knee pain due to OA.