Embolized cerebral arteriovenous malformations: a multivariate analysis of 101 excised specimens.

OBJECTIVE: Endovascular approaches have evolved from a technique practiced at very few centers to a widely available option in the management of arteriovenous malformations (AVMs) of the central nervous system. Embolization can be employed as definitive therapy or as an adjunct to surgical excision. A wide variety of embolic agents have been successfully developed and used in the clinical setting. In addition to facilitating vascular occlusion, embolic agents induce a number of reactive and destructive changes in vessel walls and the surrounding tissue. However, studies examining the pathological changes induced by different embolic agents and varying times of exposure are scarce. The goal of the present study was to compare embolic agents and time of exposure on the pathology in excised specimens. METHODS: The records of the Department of Pathology at the London Health Sciences Centre were searched for embolized AVMs for the 35-year period 1980-2015. All cases were reevaluated for clinical and technical variables and standardized histopathological findings. Cases were grouped by embolic agent, volume of agent used, and time to excision. RESULTS: A total of 101 specimens were identified. Embolic agents were invariably associated with a range of pathological findings, some of which may affect the integrity of vessel walls or the reestablishment of flow, thrombosis, acute and chronic inflammatory changes, angionecrosis, extravasation, and recanalization. The type of embolic agent did not predict differences in the incidence or severity of histopathological changes. Larger volumes of embolic agent were associated with a greater proportion of vessels containing embolic material. AVMs excised early (< 1 week postembolization) contained more acute vasculitis, while those excised later (≥ 1 week postembolization) were more likely to exhibit recanalization and foreign body giant cell infiltrates. CONCLUSIONS: Embolic agents induce a predictable range and temporal progression of pathological changes in cerebral AVMs. The embolic agents studied are indistinguishable in terms of the range and frequency of pathological reactions induced. Greater volumes of embolic agent are associated with more abundant agent within the lesion, but the proportion of vessels and vascular cross-sectional areas containing agent is small. Several changes are significantly associated with time postembolization. Acute vasculitis is a more common finding in the 1st week, while recanalization and foreign body-type granulomatous inflammation are more common at 1 week and beyond.

Into the abyss: diabetes process of care indicators and outcomes of defaulters from a Canadian tertiary care multidisciplinary diabetes clinic.

BACKGROUND: Continuity of care is essential for good quality diabetes management. We recently found that 46% of patients defaulted from care (had no contact with the clinic for 18 months after a follow-up appointment was ordered) in a Canadian multidisciplinary tertiary care diabetes clinic. The primary aim was to compare characteristics, diabetes processes of care, and outcomes from referral to within 1 year after leaving clinic or to the end of the follow-up period among those patients who defaulted, were discharged or were retained in the clinic. METHODS: Retrospective cohort study of 193 patients referred to the Foustanellas Endocrine and Diabetes Center (FEDC) for type 2 diabetes from January 1, 2005 to June 30, 2005. The FEDC is the primary academic referral centre for the Ottawa Region and provides multidisciplinary diabetes management. Defaulters (mean age 58.5 ± 12.5 year, 60% M) were compared to patients who were retained in the clinic (mean age 61.4 ± 10.47 years, 49% M) and those who were formally discharged (mean age 61.5 ± 13.2 years, 53.3% M). The chart audit population was then individually linked on an individual patient basis for laboratory testing, physician visits billed through OHIP, hospitalizations and emergency room visits using Ontario health card numbers to health administrative data from the Ministry of Health and Long-Term Care at the Institute for Clinical and Evaluative Sciences (ICES). RESULTS: Retained and defaulted patients had significantly longer duration of diabetes, more microvascular complications, were more likely to be on insulin and less likely to have a HbA1c < 7.0% than patients discharged from clinic. A significantly lower proportion of patients who defaulted from tertiary care received recommended monitoring for their diabetes (HbA1c measurements, lipid measurements, and periodic eye examinations), despite no difference in median number of visits to a primary care provider (PCP). Emergency room visits were numerically higher in the defaulters group. CONCLUSIONS: Patients defaulting from a tertiary care diabetes hospital do not receive the recommended monitoring for their diabetes management despite attending PCP appointments. Efforts should be made to minimize defaulting in this group of individuals.

Dural cavernous angioma: a preoperative diagnostic challenge.

BACKGROUND: Dural cavernous angiomas are uncommon benign vascular malformations which may present intraoperative difficulties in hemostasis when the diagnosis is not suspected preoperatively. Preoperative diagnosis can be difficult when angiomas show atypical features and share imaging characteristics with other entities. METHODS: A patient presented with a radiographically aggressive lesion, subsequently identified as a dural cavernous angioma. The lesion is reviewed and its clinical, radiographic, and pathological features are compared with other vascular malformations. CASE REPORT: A 40-year-old man presented with new onset seizures and an enhancing lesion infiltrating the floor of the right middle cranial fossa. Due to its aggressive radiographic appearance, initial considerations included chondrosarcoma, meningioma or metastasis. Pathological examination, however, revealed the lesion to be a cavernous angioma of dura. CONCLUSION: This uncommon lesion may present a diagnostic challenge with significant intraoperative implications. T2 sequence hyperintensity in a relevant lesion should raise suspicion of an hemangioma. It is important to be aware of this entity and its potential to mimic other entities on radiographic grounds.