Cortical atrophy in chronic subdural hematoma from ultra-structures to physical properties.

Several theories have tried to elucidate the mechanisms behind the pathophysiology of chronic subdural hematoma (CSDH). However, this process is complex and remains mostly unknown. In this study we performed a retrospective randomised analysis comparing the cortical atrophy of 190 patients with unilateral CSDH, with 190 healthy controls. To evaluate the extent of cortical atrophy, CT scan images were utilised to develop an index that is the ratio of the maximum diameter sum of 3 cisterns divided by the maximum diameter of the skull at the temporal lobe level. Also, we reported, for the first time, the ultrastructural analyses of the CSDH using a combination of immunohistochemistry methods and transmission electron microscopy techniques. Internal validation was performed to confirm the assessment of the different degrees of cortical atrophy. Relative Cortical Atrophy Index (RCA index) refers to the sum of the maximum diameter of three cisterns (insular cistern, longitudinal cerebral fissure and cerebral sulci greatest) with the temporal bones' greatest internal distance. This index, strongly related to age in healthy controls, is positively correlated to the preoperative and post-operative maximum diameter of hematoma and the midline shift in CSDH patients. On the contrary, it negatively correlates to the Karnofsky Performance Status (KPS). The Area Under the Receiver Operating Characteristics (AUROC) showed that RCA index effectively differentiated cases from controls. Immunohistochemistry analysis showed that the newly formed CD-31 positive microvessels are higher in number than the CD34-positive microvessels in the CSDH inner membrane than in the outer membrane. Ultrastructural observations highlight the presence of a chronic inflammatory state mainly in the CSDH inner membrane. Integrating these results, we have obtained an etiopathogenetic model of CSDH. Cortical atrophy appears to be the triggering factor activating the cascade of transendothelial cellular filtration, inflammation, membrane formation and neovascularisation leading to the CSDH formation.

Evaluating the association between blood genotype or phenotype and haemoplasma infection in UK and Italian cats.

BACKGROUND: In humans, blood groups are associated with varying prevalence of infections. The aim of this study was to determine if associations exist between the feline AB blood group system and haemoplasma infection. METHODS: Data from two studies were combined. In the first study, DNA samples from 131 haemoplasma-infected and 132 haemoplasma-uninfected UK cats underwent pyrosequencing to determine their blood genotype as AA, Ab or bb. In the second study, blood samples from 160 Italian cats of known blood phenotype A, B or AB underwent PCR testing for feline haemoplasma species DNA. RESULTS: Haemoplasma infection was demonstrated in cats of all phenotypes and genotypes. A significantly higher number of Ab genotype cats tested positive for overall haemoplasma infection status (p = 0.04) and for Mycoplasma haemofelis infection (p = 0.03). LIMITATIONS: Haemoplasma-infected Italian cats were few, possibly increasing the chance of type II error, and the presence of purebred cats in the sample population may have had a confounding effect. CONCLUSIONS: Feline haemoplasmas do not appear to preferentially use either blood type A or B antigens as attachment sites for erythrocyte colonisation. Further investigations in a larger number of haemoplasma-infected cats of known blood phenotype are warranted to explain the association between genotype Ab and haemoplasma infection.

En Bloc Resection of Solitary Brain Metastasis: The Role of Perilesional Edema.

BACKGROUND/AIM: The treatment of solitary brain metastasis is a challenging intervention since the incidence increases and prognosis is poor. This study investigated the role of perilesional edema in the overall mass effect of solitary brain metastasis. PATIENTS AND METHODS: We conducted a retrospective analysis on 88 patients with single supratentorial brain metastasis and concomitant perilesional edema undergoing en bloc resection. Each patient was evaluated for perilesional brain edema grading. We stratified patients into three groups based on the size of the metastatic lesion and the extent of perilesional edema. RESULTS: The grade of perilesional edema at 30 days after surgical removal did not correlate with the maximum diameter of the metastasis (Pearson's correlation 0.098, p=0.494). In patients with a maximal metastatic diameter ≤2 cm, the grade of perilesional edema before surgical treatment was 1.63 (STD 0.43), while 30 days after removal it was significantly reduced; 0.47 (STD 0.26), p<0.001. CONCLUSION: The overall mass effect of solitary supratentorial brain metastases is not correlated to the size of the lesion and the grade of the associated perilesional edema should be considered. Surgical en bloc resection can be considered the first choice of treatment in the presence of solitary metastasis ≤2 cm in maximal diameter but with high-grade edema, since this treatment reduces the overall mass effect.