Background: Current recommended treatment options for primary headache disorders are suboptimal in that effective pain relief is untimely and associated with side effects. Objective: The primary aim of this thesis was to evaluate the effectiveness and attitudes towards an alternative treatment option, the sphenopalatine ganglion (SPG) block which belongs to a class of procedures known as peripheral nerve blocks (PNBs). Methods: We conducted a systematic review and meta-analysis studying the effectiveness of PNBs for the treatment of primary headache disorders. We also conducted a national postal survey among Canadian emergency physicians to identify current practice patterns and perspectives on PNBs. Results: We found PNBs are effective for rapid pain relief compared to placebo at 15 minutes (MD = -1.17; 95% CI: -1.82 to -0.51) and 30 minutes (MD = -0.99; 95% CI: -1.66 to -0.32). Only 55.6% of physicians have experience with PNBs (95% CI: 0.48 to 0.65) and we discovered the SPG block is the least commonly practiced type of PNB; the majority of physicians believe these procedures are safe (85%) and effective (55.1%). A future trial is needed to compare the SPG block against standard treatment. Conclusion: The SPG block may be used as an adjunct therapy for faster effective pain relief. Current physicians would consider PNBs as a first-line alternative given evidence from a future trial. A future trial is needed to compare the SPG block against standard treatment.

Background: Single-cohort studies suggest that second-generation stents (SGS; “mesh stents”) may improve carotid artery stenting (CAS) outcomes by limiting peri- and postprocedural cerebral embolism. SGS differ in the stent frame construction, mesh material, and design, as well as in mesh-to-frame position (inside/outside). Objectives: To compare clinical outcomes of SGS in relation to first-generation stents (FGSs; single-layer) in CAS. Methods: We performed a systematic review and meta-analysis of clinical studies with FGSs and SGS (PRISMA methodology, 3302 records). Endpoints were 30-day death, stroke, myocardial infarction (DSM), and 12-month ipsilateral stroke (IS) and restenosis (ISR). A random-effect model was applied. Results: Data of 68,422 patients from 112 eligible studies (68.2% men, 44.9% symptomatic) were meta-analyzed. Thirty-day DSM was 1.30% vs. 4.11% (p < 0.01, data for SGS vs. FGS). Among SGS, both Casper/Roadsaver and CGuard reduced 30-day DSM (by 2.78 and 3.03 absolute percent, p = 0.02 and p < 0.001), whereas the Gore stent was neutral. SGSs significantly improved outcomes compared with closed-cell FGS (30-day stroke 0.6% vs. 2.32%, p = 0.014; DSM 1.3% vs. 3.15%, p < 0.01). At 12 months, in relation to FGS, Casper/Roadsaver reduced IS (−3.25%, p < 0.05) but increased ISR (+3.19%, p = 0.04), CGuard showed a reduction in both IS and ISR (−3.13%, −3.63%; p = 0.01, p < 0.01), whereas the Gore stent was neutral. Conclusions: Pooled SGS use was associated with improved short- and long-term clinical results of CAS. Individual SGS types, however, differed significantly in their outcomes, indicating a lack of a “mesh stent” class effect. Findings from this meta-analysis may provide clinically relevant information in anticipation of large-scale randomized trials.

Systematic reviews on diagnostic test accuracy studies provide an overview of the current literature in a systematic and transparent manner. They are the highest level of evidence in clinical research, therefore they are critical to decision-making in the healthcare setting. Cancer is the primary source of mortality in Canada, however early detection of tumors can improve the survival rates and long-term health outcomes of patients. The primary method of cancer diagnosis is histopathological assessment, however, its use remains controversial. It is an invasive procedure and requires resources and clinical expertise not readily available. Noninvasive clinical imaging has been studied as a clinically desirable method for cancer diagnosis, however its diagnostic accuracy has yet to be established in the medical setting. With the increased role of DTA research in medicine, the current literature needs to be summarized in an effective way to properly educate and influence clinical decision-making. The objective of this thesis is to address the current evidence gaps in DTA research by conducting several systematic reviews to evaluate the accuracy of diagnostic methods in cancer-related imaging. The last chapter of the thesis will provide a critical reflection on the current landscape of DTA studies in cancer-related imaging, based on the findings of the reviews in the thesis.