ABSTRACT
BACKGROUND AND OBJECTIVES: There has been a rise in minimally invasive methods to access the intervertebral disk space posteriorly given their decreased tissue destruction, lower blood loss, and earlier return to work. Two such options include the percutaneous lumbar interbody fusion through the Kambin triangle and the endoscopic transfacet approach. However, without accurate preoperative visualization, these approaches carry risks of damaging surrounding structures, especially the nerve roots. Using novel segmentation technology, our goal was to analyze the anatomic borders and relative sizes of the safe triangle, trans-Kambin, and the transfacet corridors to assist surgeons in planning a safe approach and determining cannula diameters. METHODS: The areas of the safe triangle, Kambin, and transfacet corridors were measured using commercially available software (BrainLab, Munich, Germany). For each approach, the exiting nerve root, traversing nerve roots, theca, disk, and vertebrae were manually segmented on 3-dimensional T2-SPACE magnetic resonance imaging using a region-growing algorithm. The triangles' borders were delineated ensuring no overlap between the area and the nerves. RESULTS: A total of 11 patients (65.4 ± 12.5 years, 33.3% female) were retrospectively reviewed. The Kambin, safe, and transfacet corridors were measured bilaterally at the operative level. The mean area (124.1 ± 19.7 mm2 vs 83.0 ± 11.7 mm2 vs 49.5 ± 11.4 mm2) and maximum permissible cannula diameter (9.9 ± 0.7 mm vs 6.8 ± 0.5 mm vs 6.05 ± 0.7 mm) for the transfacet triangles were significantly larger than Kambin and the traditional safe triangles, respectively (P < .001). CONCLUSION: We identified, in 3-dimensional, the borders for the transfacet corridor: the traversing nerve root extending inferiorly until the caudal pedicle, the theca medially, and the exiting nerve root superiorly. These results illustrate the utility of preoperatively segmenting anatomic landmarks, specifically the nerve roots, to help guide decision-making when selecting the optimal operative approach.
ABSTRACT
OBJECTIVES: To examine the factors that influence country self-citation rate (SCR) in clinical neurology and to assess the impact of self-citation on the ranking of the top 50 countries. METHODS: SCImago Journal & Country Rank was used to collect data for the 50 most cited countries in clinical neurology during 1996-2019. Country SCR was correlated with several productivity parameters and examined statistically. Countries that dropped in their ranking after the exclusion of self-citations were identified. RESULTS: The median (range) country SCR for the 50 most cited countries was 11.3%.(5.3%- 47%). Country SCR correlated significantly with total citable documents and total cites numbers and rankings. The exclusion of self-citations led to a drop in the ranking of 8(16%) countries only. No significant difference between the total and net total cites rankings was observed. CONCLUSIONS: Self-citation can be appropriate and reflect an expansion on earlier research. Highly cited productive countries tend to have high country SCR. Excluding self-citations had minimal impact on the ranking of the top 50 countries. Our findings indicate that self-citation is unlikely to influence country standing amongst the top 50 and does not support the argument for eliminating self-citations from citation-based metrics. A more globalization through international collaboration in research is encouraged.
ABSTRACT
Objectives The purpose of the study was to evaluate the impact of country self-citation rate (SCR) among medical specialties in Saudi Arabia, and to assess the impact of self-citations on the country's total cites world ranking in different specialties. Methods SCImago Journal & Country Rank (SJR) was used to collect data related to all medical specialties in Saudi Arabia for the period 1996-2019. The country SCR for the specialties was correlated with several bibliometric parameters and examined statistically. The specialties that showed a drop in Saudi Arabia's total cites world ranking following the exclusion of self-citations were identified. Results The median country SCR for 46 specialties in Saudi Arabia was 9.5% (range: 4.6-23.1%). The two specialties with the highest country SCR were Public Health (23.1%) and Family Practice (22.9%). Country SCR was significantly higher in the non-clinical specialties compared to clinical specialties (15.3% vs. 9.6%). It did not correlate significantly with any of the examined productivity indices. The exclusion of self-citations resulted in a drop in Saudi Arabia's total cites world ranking in six (13%) specialties only. There was no significant difference between the country's total cites and net total cites world rankings in the specialties. Conclusions Self-citation may be appropriate and signify an expansion of the authors' previous work. Country SCR in medical specialties in Saudi Arabia is relatively low and not affected by total documents and total cites. Non-clinical specialties tend to self-cite more. The exclusion of self-citations had minimal effect on Saudi Arabia's total cites world ranking, indicating that country SCR in the specialties is unlikely to impact its international scientific standing. Our findings do not support the argument for eliminating self-citation from citation-based metrics. We believe that more collaborative and global research practices should be encouraged.
ABSTRACT
BACKGROUND: Anterior clinoidal meningiomas (ACM) are traditionally approached through transcranial routes. Due to their tendency to extend laterally and their proximity to vital neurovascular structures, the endoscopic transnasal suprasellar approach is still questionable. We present and describe an ACM case that underwent an endoscopic transnasal suprasellar approach, and provide a review of the literature and operative technique. CASE DESCRIPTION: A 56 year-old lady who presented with chronic left-sided decreased vision. Brain imaging revealed a lesion measuring 9 × 10 × 11 mm attached to the left anterior clinoid process (ACP) and extending to the left optic canal. Lesion was compressing the left optic nerve (ON) and abutting the supraclinoid part of the left internal carotid artery (ICA). Utilizing the endoscopic transnasal suprasellar approach, the meningioma was resected and the optic canal was decompressed. Reconstruction was achieved using fascia lata, vomer bone, and nasoseptal flap. A lumbar drain was inserted perioperatively. Patient had no perioperative morbidity and retained vision in the affected eye. CONCLUSIONS: Resection of selected ACMs can be safely achieved utilizing the endoscopic transnasal suprasellar approach. Although the literature lacks long-term outcome comparison between the transnasal and the traditional transcranial approaches, specifically addressing ACMs, this technique is becoming more popular over the last decade. More efforts should be directed towards implementing and reporting the endoscopic transnasal suprasellar approach for meningiomas of the anterior clinoid process.
