# Positron Emission Tomography in Cerebral Amyloid Angiopathy: A Scoping Review
## 3 Results
### Pathology-Proven CAA  
The studies consistently identify occipital-dominant amyloid deposition as a hallmark of probable CAA. For example, [PERSON] et al. [41] reported an SUVR of 1.65 \(\pm\) 0.2 in the occipital lobe of probable CAA patients, significantly higher than in AD patients or controls (\(p\) < 0.001). Similarly, [PERSON] et al. [42] found an even higher occipital SUVR (1.7 \(\pm\) 0.3) in probable CAA cases, emphasizing the diagnostic value of this regional amyloid pattern. Recurrent ICH episodes in probable CAA are linked to higher regional amyloid deposition. [PERSON] et al. [41] demonstrated that PET imaging predicted ICH recurrence with 83% sensitivity, highlighting its prognostic utility. Furthermore, another study [43] reported a significant correlation (r = 0.58, \(p\) < 0.01) between regional amyloid uptake and cortical microbleeds, a critical marker of disease severity. The study of [PERSON] et al. [32] focused on the role of cSS in CAA pathology, noting that probable CAA patients with cSS had a higher occipital amyloid SUVR and greater posterior \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Reference** & **Probable CAA/ICH** & **Possible CAA** & **Controls** & **Key Findings** \\ \hline [PERSON] et al., & & & & Probable CAA patients showed a 1.5-fold increase in occipital amyloid PET SUVR compared to controls (\(p\) < 0.01). & \\ [PERSON] et al., & & & & Probable CAA patients had a 40\% higher occipital SUVR compared to Alzheimer’s patients (\(p\) < 0.001), & \\
2024 [27] & 42 & 15 & 30 & SUVR compared to Alzheimer’s patients (\(p\) < 0.001), & \\ [PERSON] et al., & & & & which correlated with recurrent lobar ICH. & \\
2018 [32] & 64 & 25 & 35 & Out of all probable CAA cases, 73\% showed occipital-predominant amyloid uptake, compared to 18\% of Alzheimer’s cases (\(p\) < 0.001). & \\ [PERSON] et al., & & & & A strong correlation was found between occipital amyloid uptake and lobar microbleeds (r = 0.62, \(p\) < 0.001). & \\ [PERSON] et al., & & & & An increased regional amyloid burden in probable CAA predicted ICH recurrence with 85\% sensitivity and 82\% specificity. & \\ [PERSON] et al., & & & & Probable CAA patients showed a 2-fold higher occipital-to-global SUVR compared to possible CAA patients (\(p\) < 0.01). & \\ [PERSON] et al., & & & & Amyloid PET uptake was significantly higher in \\
2015 [38] & 39 & 12 & 25 & probable CAA with lobar microbleeds compared to \\ [PERSON] et al., & & & & hypertensive ICH with an AUC of 0.87 (95\% CI: 0.81-0.92, \(p\) < 0.001). & \\ [PERSON] et al., & & & & The occipital-to-global amyloid ratio was higher in \\
2022 [28] & 57 & 23 & 30 & probable CAA than Alzheimer’s disease (mean SUVR 1.8 \(\pm\) 0.3 vs. 1.2 \(\pm\) 0.4, \(p\) < 0.001). & \\ [PERSON] et al., & & & & Probable CAA patients showed a significant amyloid burden (SUVR 1.6 \(\pm\) 0.2) compared to controls (\(p\) < 0.001), which was correlated with ICH. & \\ [PERSON] et al., & & & & A higher amyloid burden was found in recurrent ICH cases (SUVR 1.7 \(\pm\) 0.3, \(p\) = 0.02); the occipital SUVR was elevated in probable CAA. & \\ [PERSON] et al., & & & & Amyloid PET had 87\% sensitivity and 78\% specificity for diagnosing probable CAA in ICH patients compared to controls. & \\ [PERSON] et al., & & & & The occipital SUVR was 50\% higher in probable CAA patients compared to hypertensive ICH patients (\(p\) < 0.001). & \\ [PERSON] et al., & & & & Regional amyloid deposition was found to be correlated with ICH burden and distribution (r = 0.58, \(p\) < 0.01). & \\ [PERSON] et al., & & & & & Regional amyloid deposition was found to be correlated with ICH burden and distribution (r = 0.58, \(p\) < 0.01). & \\
2019 [34] & 47 & 18 & 27 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Findings of selected studies on probable and possible CAA and amyloid PET. cortical atrophy than those without cSS. This suggests that CSS exacerbates both amyloid pathology and structural brain damage.