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To the Editor: In anticipation of a surge in patients with the coronavirus disease of 2019 (COVID-19), neurosurgical patients across the majority of the United States with nonemergent conditions had their elective surgery postponed indefinitely. In preparation for the reopening of the surgical system and trying to prioritize which cases should go first, we produced a system by using the Delphi method to achieve general consensus. Neurosurgeons actively practicing in 2 separate geographic regions of the United States where "black level" COVID-19 surges occurred (the New York Metropolitan Area and Detroit, Michigan) participated in the process. We categorized a total of 86 unique neurosurgical scenarios into 6 tiers of priority and reached a consensus (>75% agreement) or majority opinion (>50%) on the timing of surgery on all except 1 case type (central cord syndrome). Here we present a guide that can assist neurosurgical departments prioritize the relative urgency of cases, whether it be due to a pandemic or any other scenario where the normal workflow has been severely disrupted.

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Background: The quantitative assessment of supraspinatus tendons by conventional magnetic resonance is limited by low contrast-to-noise ratio (CNR). Magnetic resonance imaging (MRI) scanners operating at 7 Tesla offer high signal-to noise ratio (SNR), low CNR and high spatial resolution that are well-suited for rapidly relaxing tissues like tendons. Few studies have applied T2 and T2* mapping to musculoskeletal imaging and to the rotator cuff tendons. Our objective was to analyze the T2 and T2* relaxation times from surgically repaired supraspinatus tendons and the effect of bone channeling.Methods: One supraspinatus tendon of 112 adult female New Zealand white rabbits was surgically detached and repaired one week later. Rabbits were randomly assigned to channeling (n=64) or control (n=48) groups and harvested at 0, 1, 2, and 4 weeks. A 7T magnet was used for signal acquisition. For T2 mapping, a sagittal multi slice 2D multi-echo spin-echo (MESE) CPMG sequence with fat saturation was applied and T2* mapping was performed using a 3D UTE sequence. Magnetic resonance images from supraspinatus tendons were analyzed by two raters. Three regions of interest were manually drawn on the first T2-weighted dataset. For T2 and T2*, different ROI masks were generated to obtain relaxation times.Results: T2-weighted maps but not T2*-weighted maps generated reliable signals for relaxation time measurement. Torn supraspinatus tendons had lower T2 than controls at the time of repair (20.0±3.4 vs. 25.6±3.9 ms; P<0.05). T2 increased at 1, 2 and 4 postoperative weeks: 22.7±3.1, 23.3±3.9 and 24.0±5.1 ms, respectively, and values were significantly different from contralateral supraspinatus tendons (24.8±3.1; 26.8±4.3 and 26.5±3.6 ms; all P<0.05). Bone channeling did not affect T2 (P>0.05).Conclusions: Supraspinatus tendons detached for 1 week had shorter T2 relaxation time compared to contralateral as measured with 7T MRI.

The divalent nickel isothiocyanate coordination polymer [Ni(NCS)2(dpa)2] (1) has been prepared in high yield via the hydrothermal combination of Ni(SCN)2 with the kinked tethering ligand 4,4′‐dipyridylamine (dpa), and characterized via single crystal X‐ray diffraction, infrared spectroscopy and elemental and thermal analysis. 1 manifests offset stacked 2‐D (4,4)‐topology layered motifs organized into 3‐D via interlamellar supramolecular N–H···S hydrogen bonding. Hydrothermal reaction of CuCl2·2H2O, NaSCN, and dpa afforded the copper (I) thiocyanate coordination polymer [Cu2(SCN)2(dpa)] (2), whose single crystal structure revealed unprecedented 1‐D [Cu2(SCN)2] zig‐zag staircase motifs constructed via connection of the Cu2S2 “stair steps” at their adjacent sides via μ3‐1,1,3‐SCN anions. The 3‐D structure of 2 is propagated by covalent linkage of each [Cu2(SCN)2] staircase to four others through dipodal dpa tethering ligands, enhanced by N–H···S and C–H···S supramolecular interactions to two other staircases.

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