Indocyanine green angiography imaging findings in artery occlusions

Purpose: To describe the multimodal imaging features including indocyanine green angiography (ICGA) in cases diagnosed clinically as central retinal artery occlusion (CRAO) at its different disease stages. Methods: In this retrospective observational study, patients diagnosed clinically as CRAO or hemi-CRAO were included. All patients underwent multimodal imaging with optical coherence tomography (OCT), fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were studied. Analysis of ICGA images in different stages of artery occlusions and its correlation with accompanying FFA and OCT images was done. Results: Eight such studies in five patients were available for analysis. The most important observation noted on ICGA was the presence of hypercyanescent spots seen during the acute stages of the disease in four of the five cases. The spots were accompanied by retinal vessel staining on FFA in the corresponding region. As the disease showed signs of resolution, the hypercyanescent spots on ICGA and retinal vessel staining on FFA disappeared. The hypercyanescent spots seen on the ICGA were noted due to the red blood cell aggregation or ‘rouleaux’ formation. In addition, choroidal perfusion abnormalities were noted on ICGA in all five cases in the acute stage. Conclusion: Choroidal perfusion changes can be identified in acute phase of retinal artery occlusion. Rouleaux formation in the retinal circulation occurs due to the slowing of the blood flow following artery occlusion. These are seen as hypercyanescent spots in the late phase on ICGA.

RETROSPECTIVE ANALYSIS OF MULTIPLE MYELOMA PATIENTS IN A TERTIARY CARE CENTRE OF UTTARAKHAND

Introduction: Multiple myeloma (MM) is a hemato-lymphoid malignancy of B-cell type. It occurs due to the accumulation of malignant monoclonal plasma cells. The exact incidence of MM in India is not well-known. The current study presented the clinical characteristics, radiological findings and laboratory findings of MM patients who were initially treated at the tertiary care centre, Dehradun, Uttarakhand (India). Material and methods: Retrospective analysis of the medical records of 123 consecutive patients with MM who were initially presented to Hemato-Oncology department during the period from January 2014 to December 2018. Peripheral blood finding, bone marrow diagnosis, flow-cytometry analysis, serum protein and immunofixation electrophoresis finding, biochemical parameter, histo-pathological and cytological diagnosis, if any, urine examination finding and radiological examination of cases shall be compiled and tabulated. Diagnosis of symptomatic multiple myeloma was done based on The International Myeloma Working Group criteria for the diagnosis of MM. Result: The study included 123 cases of multiple myeloma with male: female ratio of 2:1, mean age of 59.88 ±11.08 years and range of 32-87 years. The back pain (n=106, 86.2%) was the common presenting complaint followed by inability to walk (n=90,73.2%). CT scan and/or MRI scan finding of MM patients, the lytic lesion was found in 107 patients (87%) and was found significant with its correlation with ISS/DS plus staging system (pvalue 0.013). The most location was dorso-lumbar spine (n=72, 67.28%) followed by skull (n=37, 34.58%) and ribs (n=19, 17.75%). Hemoglobin (Hb) analysis showed 92.7 % (n=114) cases were anemic with mostly had normocytic (n=95,77.2%). 62.6%(n=77) of cases showed rouleaux formation while 23.57% (n=29) cases were circulating plasmacytoid lymphocytes or plasma cells. The raised ESR values was found in 89.33% (n=67) of cases. Diagnosis of cases shows 99.2% (n=122) of cases diagnosed as secretory MM while 1 (0.8%) case diagnosed as non-secretory MM. Conclusion: MM is a disease with a inconsistent clinical presentation with multiple system involvement. Younger age of disease onset is some noteworthy features of myeloma in Uttarakhand state of India. Bony pain associated with generalized weakness is the commonest presentation, normocytic normochromic anemia with rouleaux formation, raised ESR, raised total protein with hypoalbuminemia, hypercalcemia, presence of M band and presence of >10% plasma cell in bone marrow is clue to diagnosis in MM cases . Keywords: Multiple Myeloma, Uttrakhand, Hemato-lymphoid malignancy

Accounting for residence-time in blood rheology models: do we really need non-Newtonian blood flow modelling in large arteries?

Patient-specific computational fluid dynamics (CFD) is a promising tool that provides highly resolved haemodynamics information. The choice of blood rheology is an assumption in CFD models that has been subject to extensive debate. Blood is known to exhibit shear-thinning behaviour, and non-Newtonian modelling has been recommended for aneurysmal flows. Current non-Newtonian models ignore rouleaux formation, which is the key player in blood's shear-thinning behaviour. Experimental data suggest that red blood cell aggregation and rouleaux formation require notable red blood cell residence-time (RT) in a low shear rate regime. This study proposes a novel hybrid Newtonian and non-Newtonian rheology model where the shear-thinning behaviour is activated in high RT regions based on experimental data. Image-based abdominal aortic and cerebral aneurysm models are considered and highly resolved CFD simulations are performed using a minimally dissipative solver. Lagrangian particle tracking is used to define a backward particle RT measure and detect stagnant regions with increased rouleaux formation likelihood. Our novel RT-based non-Newtonian model shows a significant reduction in shear-thinning effects and provides haemodynamic results qualitatively identical and quantitatively close to the Newtonian model. Our results have important implications in patient-specific CFD modelling and suggest that non-Newtonian models should be revisited in large artery flows.

Differentiating between cold agglutinins and rouleaux: a case series of seven patients

We present a case series of seven patients with suspected cold agglutinin antibodies, discovered after initiation of bypass. Laboratory analysis of blood samples intraoperatively determined the cause of the aggregation to be rouleaux formation in three of the patients and cold agglutinins in the other four.