Umbrella review and network meta-analysis of diagnostic imaging test accuracy studies in Differentiating between brain tumor progression versus pseudoprogression and radionecrosis.

PURPOSE: In this study we gathered and analyzed the available evidence regarding 17 different imaging modalities and performed network meta-analysis to find the most effective modality for the differentiation between brain tumor recurrence and post-treatment radiation effects. METHODS: We conducted a comprehensive systematic search on PubMed and Embase. The quality of eligible studies was assessed using the Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) instrument. For each meta-analysis, we recalculated the effect size, sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio from the individual study data provided in the original meta-analysis using a random-effects model. Imaging technique comparisons were then assessed using NMA. Ranking was assessed using the multidimensional scaling approach and by visually assessing surface under the cumulative ranking curves. RESULTS: We identified 32 eligible studies. High confidence in the results was found in only one of them, with a substantial heterogeneity and small study effect in 21% and 9% of included meta-analysis respectively. Comparisons between MRS Cho/NAA, Cho/Cr, DWI, and DSC were most studied. Our analysis showed MRS (Cho/NAA) and 18F-DOPA PET displayed the highest sensitivity and negative likelihood ratios. 18-FET PET was ranked highest among the 17 studied techniques with statistical significance. APT MRI was the only non-nuclear imaging modality to rank higher than DSC, with statistical insignificance, however. CONCLUSION: The evidence regarding which imaging modality is best for the differentiation between radiation necrosis and post-treatment radiation effects is still inconclusive. Using NMA, our analysis ranked FET PET to be the best for such a task based on the available evidence. APT MRI showed promising results as a non-nuclear alternative.

Type B Lactic Acidosis: A Very Rare but Fatal Complication of Gastrointestinal Solid Tumor.

Type B lactic acidosis, secondary to solid cancer, is very rare. It is mostly seen in patients with hematological malignancies. Although its exact pathogenesis is unknown, it is believed to be caused by overproduction and the inability of tumor cells to remove lactate. In the last 26 years, a systematic review of the literature only identified two previous reports of colorectal cancer-related type B lactic acidosis. Here, we report the third case of severe type B lactic acidosis due to stage IV colorectal with liver metastasis. Besides, this case is unique in that serum lactate levels reaching as high as 24 mmol/L were not reported in association with colorectal cancer. In most cases, the prognosis is still very poor because there are no standardized treatment recommendations. Early chemotherapy is still the only intervention that provides some survival benefits.

Point-of-Care Ultrasound to Assess Diaphragmatic Paralysis in Resource-Limited Setting: A Case Series.

Diaphragmatic dysfunction can arise from various factors, and Guillain-Barre syndrome, characterized by acute inflammatory polyradiculoneuropathy, is one such cause that may result in respiratory failure due to diaphragmatic paralysis. Prompt recognition and timely intervention, including airway protection and addressing the underlying pathology, are crucial for achieving optimal patient outcomes. Point-of-care ultrasound, specifically utilizing the M-mode function, can be employed for individuals displaying symptoms of diaphragmatic paralysis. This diagnostic approach is uncomplicated an effective tool for serial follow-up. In this context, we present a case series involving three patients with diaphragmatic paralysis in a limited-resource setting.