Optimizing the Definition of Ischemic Core in CT Perfusion: Influence of Infarct Growth and Tissue-Specific Thresholds

BACKGROUND AND PURPOSE

CTP allows estimating ischemic core in patients with acute stroke. However, these estimations have limited accuracy compared with MR imaging. We studied the effect of applying WM- and GM-specific thresholds and analyzed the infarct growth from baseline imaging to reperfusion.

MATERIALS AND METHODS

This was a single-center cohort of consecutive patients (n = 113) with witnessed strokes due to proximal carotid territory occlusions with baseline CT perfusion, complete reperfusion, and follow-up DWI. We segmented GM and WM, coregistered CTP with DWI, and compared the accuracy of the different predictions for each voxel on DWI through receiver operating characteristic analysis. We assessed the yield of different relative CBF thresholds to predict the final infarct volume and an estimated infarct growth-corrected volume (subtracting the infarct growth from baseline imaging to complete reperfusion) for a single relative CBF threshold and GM- and WM-specific thresholds.

RESULTS

The fixed threshold underestimated lesions in GM and overestimated them in WM. Double GM- and WM-specific thresholds of relative CBF were superior to fixed thresholds in predicting infarcted voxels. The closest estimations of the infarct on DWI were based on a relative CBF of 25% for a single threshold, 35% for GM, and 20% for WM, and they decreased when correcting for infarct growth: 20% for a single threshold, 25% for GM, and 15% for WM. The combination of 25% for GM and 15% for WM yielded the best prediction.

CONCLUSIONS

GM- and WM-specific thresholds result in different estimations of ischemic core in CTP and increase the global accuracy. More restrictive thresholds better estimate the actual extent of the infarcted tissue.

231 Diagnostic Outcomes in Suspected Appendicitis Before and During the COVID-19 Pandemic

Introduction

Routine operative treatment of appendicitis was temporarily interrupted during the COVID-19 pandemic. Non-operative management in suspected appendicitis makes a definitive diagnosis difficult. This study investigated diagnostic outcomes of suspected appendicitis patients before and during COVID-19.

Method

A retrospective review of patients aged 16–45 undergoing treatment for suspected appendicitis pre-COVID-19 (1st January 2019–1st January 2020) and during the COVID-19 pandemic (1st March 2020 to 31st June 2020) was performed. Patients were followed up for one year (31st June 2021) to explore diagnostic outcomes.

Results

At one year follow up, 206 patients were identified in the pre-COVID-19 cohort with 100% (n = 206) undergoing an appendicectomy. On histopathological examination 77.2% (n = 159) had appendicitis; 10.7% (n = 22) another pathology; 2.9% (n = 6) neuroendocrine tumour. There were 62 patients in the COVID-19 cohort in which 79% (n = 49) underwent appendicectomy (56% (n = 35) immediate appendicectomy; 23% (n = 13) interval appendicectomy). On histopathological examination 61% (n = 38) had appendicitis; 13% (n = 8) another pathology; 5% (n = 3) neuroendocrine tumour.

Of the remaining 13/62 patients, one had undergone a CT scan and colonoscopy for gastrointestinal symptoms demonstrating signs of chronic caecal inflammation treated conservatively. One underwent a CT scan alone for gastrointestinal symptoms finding no pathology. The remaining 11/62 patients had no further reported symptoms or diagnostics.

Conclusions

This study demonstrates that the risk of appendiceal malignancy and chronic inflammation is important in non-operative management of suspected appendicitis and establishing consistent follow up pathways is essential.

Epidemiologic and Histopathologic Characterization of Cutaneous Metastases in Patients Who Visited 2 Hospitals in Santiago de Chile Between 2005 and 2017

BACKGROUND AND OBJECTIVE

Cutaneous metastases (CMs) account for 2% of skin tumors and their incidence varies between 0.7% and 9% in patients with cancer. The objective of this study was to describe and analyze the demographic, clinical, and histopathologic characteristics of CM in patients who visited 2 hospitals in the Santiago de Chile metropolitan region.

MATERIAL AND METHOD

We performed a retrospective, descriptive, analytical, observational, cross-sectional study. We reviewed the pathology reports, patient records, pathology slides, and dates of death for diagnosed cases of CM from the anatomic pathology departments of 2 hospitals in the Santiago de Chile metropolitan region between 2015 and 2017.

RESULTS

Ninety-six patients with CM were included in the study; 60.42% were women and 39.58% were men. The mean (SD) age was 67.95 (13.74) years, with a range of 28 to 96 years. The most common primary tumor was melanoma in 27.08% of cases (n=26), followed by breast cancer (18.75%, n=18), and adenocarcinoma (15.63%, n=15). The median time between diagnosis of the tumor and cutaneous metastasis was 9 months. Patients with CM of melanoma had a higher survival rate than patients with metastasis of other primary tumors (P<.05). A histopathologic study of 91 slides showed that diffuse infiltration of the tissue with tumor cells was the most common pattern and vascular invasion was rare.

CONCLUSIONS

The results are similar to those found worldwide. CM is a rare manifestation of internal tumors. It presents mainly at an advanced age and is equally prevalent in both sexes.

177Lu-DOTATATE treatment in neuroendocrine tumours. A preliminary study

Therapy with radiolabelled somatostatin analogue peptides is a promising new therapy to treat neuroendocrine tumours. The aim of this preliminary study is to present our experience with ¹⁷⁷Lu-DOTATATE therapy, and evaluate tolerability and short-term efficacy in patients with tumours expressing somatostatin receptors. A total of 7 patients with metastatic neuroendocrine tumours were treated, each with 4 doses of ¹⁷⁷Lu-DOTATATE. The treatment response was evaluated in the form of biochemical response (tumour markers), imaging methods (somatostatin receptor scintigraphy, computed tomography, and magnetic resonance), and functional and quality of life responses using the Karnofsky performance status scale. Treatment toxicity was also evaluated. The results obtained were as follows: Biochemical response: 60% of patients showed tumour marker levels returning to normal, while they decreased significantly in the remaining 40%. Imaging response: 85.7% had a partial response, while 14.3% showed stable disease. All (100%) patients showed a significant improvement in quality of life, with increased Karnofsky scale scores. No patient had acute or chronic toxicity, and subacute transient haematological toxicity was observed in 42.8% of patients. Despite being a preliminary study, it was found that treatment with ¹⁷⁷Lu-DOTATATE is a safe treatment with few side effects, and an objective response was achieved in most patients.

Synthesis and Mesomorphic Properties of Azo Compounds Derived from Phenyl-and Thienyl-1,3,4-Thiadiazole

The synthesis and mesomorphic behaviour of new series of liquid crystals containing 1,3,4- thiadiazole and thiophene rings with azo central bond are reported (series 5a and 5b). All compounds of series 5a exhibit enantiotropic nematic mesophase and the higher homologues (n = 9 - 10) also show a monotropic smectic C phase. Series 5b show dimorphism SC - N (for n = 5 - 7 the SC is monotropic). These series are compared with the Schiff’s bases analogues, the imine bond gives rise to similar liquid crystals phase but larger mesomorphic range.

Equivalence of a single saline nebulised dose of formoterol powder vs three doses of nebulised Albuterol every twenty minutes in acute asthma in children: a suitable cost effective approach for developing nations

BACKGROUND

An increase in asthma prevalence is reported from developed as well as developing nations, with rising costs from acute asthma and great expenditures to health care systems. Venezuela's Ministry of Health ambulatory facilities care for 80 % or more of a mostly urban and impoverished population of 26 million inhabitants, registering close to a million acute asthma visits per year; a nebulised fixed fenoterol-ipratropium bromide combination (Bero-dual, Boehringer-Ingelheim) in repeated dosing is the standard treatment.

OBJECTIVES

to simplify acute asthma care and management in a cost effective manner employing Formoterol Fumarate powder, a long acting beta agonist with immediate bronchodilator effects.

METHODOLOGY

Fifty acute asthmatic children (5-12 years old) were randomly assigned (25 patients in each group) to receive either a nebulised single dose (US $1.35) of two 12 microg Formoterol Fumarate capsules (Foradil 12 microg/cap, Novartis Pharma AG, Basel, Switzerland) diluted in 2.5 ml of sterile saline solution; or 3 doses of Albuterol (US $ 6.73) every twenty minutes for one hour (Glaxo Smith Kline Albuterol ampoules, 2.5 mg/2.5 ml, at a dose of 0.15 mg/kg/dose, maximum dose 2.5 mg). Symptoms score, oxygen saturation and lung function testing were recorded before and one hour after commencing treatments.

RESULTS

Both groups improved significantly on all parameters, except for FEV(1) in the Albuterol group.

CONCLUSIONS

Single dose nebulised Formoterol Fumarate (dry powder) in sterile saline solution, as depicted in this trial, is equivalent to three doses of Albuterol every twenty minutes for one hour in acute asthma in children, simplifying acute care management and at one fifth of medication costs. A pursuit of simpler and more cost effective approaches is found wanting in developing nations with depressed economies and unique cultural and socio-medical contexts; also, in countries where pharmaco-economics orients quality of health policies, novel approaches like this are worth exploring.

[Spontaneous pneumothorax and active pulmonary tuberculosis]

We report three HIV-negative patients with spontaneous pneumothorax as clinical manifestation of active tuberculosis acute chest pain and dyspnea was the cause of admission. Chest roentgen grams showed lung collapse and parenchymal cavitation in two of therm and hydropneumothorax in the other. Outcome was favorable with antituberculous drug therapy and placement of chest tube. Although spontaneous pneumothorax is frequent in fibrosis pulmonary tuberculosis, it seldom complicated active tuberculosis in spite of increase of its incidence.