Visual Field Outcome Reporting in Neurosurgery: Lessons Learned from a Prospective, Multicenter Study of Transsphenoidal Pituitary Surgery

The RAPID Consortium: A Platform for Clinical and Translational Pituitary Tumor Research

Objectives  Pituitary tumor treatment is hampered by the relative rarity of the disease, absence of a multicenter collaborative platform, and limited translational-clinical research partnerships. Prior studies offer limited insight into the formation of a multicenter consortium. Design  The authors describe the establishment of a multicenter research initiative, Registry of Adenomas of the Pituitary and Related Disorders (RAPID), to encourage quality improvement and research, promote scholarship, and apply innovative solutions in outcomes research. Methods  The challenges encountered during the formation of other research registries were reviewed with those lessons applied to the development of RAPID. Setting/Participants  RAPID was formed by 11 academic U.S. pituitary centers. Results  A Steering Committee, bylaws, data coordination center, and leadership team have been established. Clinical modules with standardized data fields for nonfunctioning adenoma, prolactinoma, acromegaly, Cushing's disease, craniopharyngioma, and Rathke's cleft cyst were created using a Health Insurance Portability and Accountability Act-compliant cloud-based platform. Currently, RAPID has received institutional review board approval at all centers, compiled retrospective data and agreements from most centers, and begun prospective data collection at one site. Existing institutional databases are being mapped to one central repository. Conclusion  The RAPID consortium has laid the foundation for a multicenter collaboration to facilitate pituitary tumor and surgical research. We sought to share our experiences so that other groups also contemplating this approach may benefit. Future studies may include outcomes benchmarking, clinically annotated biobank tissue, multicenter outcomes studies, prospective intervention studies, translational research, and health economics studies focused on value-based care questions.

Cisternal, Falciform, and Optic Canal Decompression Influencing Optic Nerve Biomechanics: A Microsurgical Anatomic Study

BACKGROUND

Questions remain regarding optic nerve (ON) physiology, mechanical compliance, and microvasculature, particularly surgical outcomes and atypical visual field defects associated with sellar/parasellar pathology (eg, tumors and aneurysms).

OBJECTIVE

To study the microsurgical/histological anatomy of each ON segment and corresponding microvasculature, calculate area of optic-carotid space at each decompression stage, and measure ON tension before/after compression.

METHODS

Five cadaveric heads (10 sides) underwent sequential dissection: (1) intradural (arachnoidal) ON dissection; (2) falciform ligament opening; (3) anterior clinoidectomy, optic canal decompression, and ON sheath release. At each step, we pulled the nerve superiorly/laterally with a force meter and measured maximal mobility/mechanical tension in each position.

RESULTS

Cisternal ON microvasculature was more superficial and less dense vs the orbital segment. ON tension was significantly lower with higher mobility when manipulated superiorly vs lateromedially. Optic-carotid space significantly increased in size at each decompression stage and with ON mobilization both superiorly and laterally, but the increase was statistically significant in favor of upward mobilization. At decompression step, upward pull provided more space with less tension vs side pull. For upward pull, each step of decompression provided added space as did side pull.

CONCLUSION

Opening the optic canal, falciform ligament, and arachnoid membrane decompresses the ON for safer manipulation and provided a wider optic-carotid surgical corridor to access sellar/parasellar pathology. When tailoring decompression, the ON should be manipulated superiorly rather than lateromedially, which may guide surgical technique, help prevent intraoperative visual deterioration, facilitate postoperative visual improvement, and help understand preoperative visual field deficits based on mechanical factors.

Quality of care evaluation in non-functioning pituitary adenoma with chiasm compression: visual outcomes and timing of intervention clinical recommendations based on a systematic literature review and cohort study

PURPOSE

Surgery in patients with non-functioning pituitary macroadenomas (NFMA) is effective in ameliorating visual function. The urgency for decompression, and preferred timing of surgery related to the preoperative severity of dysfunction is unknown.

METHODS

Systematic review for evidence to provide clinical guidance for timing of surgical decompression of the optic chiasm, and a cohort study of 30 NFMA patients, in whom mean deviation (MD), and severity of visual dysfunction was assessed.

RESULTS

Systematic review 44 studies were included with a total of 4789 patients. Postoperatively, visual field defects improved in 87.0% of patients, stabilized in 12.8% and worsened in 1.0%. Specific protocols regarding timing of surgery were not reported. Only seven studies (16.7%) reported on either the duration of visual symptoms, or diagnostic, or treatment delay. Cohort study 30 NFMA patients (50% female, 60 eyes, mean age 58.5 ± 14.8 years), had a median MD of - 5.3 decibel (IQR - 3.1 to - 10.1). MD was strongly correlated with clinical severity (r =  - 0.94, P < 0.0001), and were used for severity of defects cut-off values: (1) normal >  - 2 dB, (2) mild - 2 dB to - 4 dB, (3) moderate - 4 to - 8 dB, (4) severe - 8 to - 17 dB, (5) very severe <  - 17 dB.

CONCLUSION

Surgical decompression is highly effective in improving visual function. Uniform, quantitative grading of visual dysfunction was lacking. MD is a promising quantitative outcome measure. We provide recommendations for the evaluation of timing of surgery, considering severity of visual impairment, which will need further validation based on expert clinical practice.