Diagnostic Yield and Safety of Brain Biopsy for Suspected Primary Central Nervous System Angiitis

Abstract

Background and Purpose-The utility and safety of brain biopsy for suspected primary angiitis of the central nervous system (PACNS) are uncertain. Factors predictive of a positive biopsy have not been well described. Our aim was to evaluate the diagnostic yield and safety of brain biopsy in suspected PACNS and determine whether any prebiopsy variables are associated with a positive biopsy. Methods-This is a retrospective study of consecutive patients who underwent diagnostic brain biopsy for PACNS at a single institution. The relationship between biopsy yield and patient demographics, surgical technique, laboratory testing, neuroimaging, biopsy characteristics, and prebiopsy immunosuppressive therapy were examined. Results-PACNS was confirmed in 9 of 79 patients (11%). Biopsy identified alternative diagnoses in 24 patients (30%), with cerebral amyloid angiopathy (8 patients), encephalitis (5 patients), demyelination (3 patients), and CNS lymphoma (3 patients) most commonly found. There was no correlation between a positive biopsy and cerebrospinal fluid results, neuroimaging, surgical technique, biopsy characteristics, or preoperative immunosuppressive therapy. Smaller biopsies (P=0.02) and closed procedures (P=0.013) were less likely to yield a diagnosis. Postoperative complications occurred in 13 patients (16%), 3 (4%) of which were serious. Conclusions-Brain biopsy leads to pathological confirmation of vasculitis in a minority of suspected PACNS cases but alternative diagnoses are often identified. Importantly, rare but meaningful complications may occur. (Stroke.

Subtypes of primary angiitis of the CNS identified by MRI patterns reflect the size of affected vessels

“…It is undoubtable that histopathological proof is the gold standard in the diagnostic work-up of PACNS patients, but the yield of positive biopsy might be lower in patients that present with recurrent strokes and vessel abnormalities on neuroimaging presumably caused by more proximal vasculitic processes which are not accessible by biopsy. In those cases, a careful selection of patients for brain biopsy is advisable especially with regard to the findings of a recently published study showing a relatively high risk of biopsy (16%) with a low yield of histopathological proof of PACNS (11%) in 79 patients who underwent biopsy for suspected PACNS 27. An alternative diagnosis could be established in 30% of cases.…”

Added Value of Vessel Wall Magnetic Resonance Imaging for Differentiation of Nonocclusive Intracranial Vasculopathies

“…DSA, however, shows limited sensitivity/specificity that can be as low as 30% for IVas, and only 25–43% of pathologically-proven primary angiitis have luminal abnormalities on angiography 4–8 . If there is suspicion for IVas, invasive tests such as brain biopsy may be implemented, which carry a significant risk of morbidity, but also show sensitivities of only 53–80% for vasculitis 9, 10 . ICAD frequently remodels outwardly, resulting in luminal-based underestimation of disease burden 11 , and luminal imaging may not detect culprit plaques at all 12 .…”

The diagnostic quality of needle brain biopsy specimens obtained with different sampling methods – Experimental study

“…This has been confirmed by Depreitere et al, who reported that the small size of biopsy samples was the primary reason for failure and problematic histological interpretation 11 . In a study by Torres et al, biopsies without useful data were substantially smaller in size than diagnostic biopsies (median 0.15 cm 3 versus 0.4 cm 3 ; P = 0.02) 43 .…”