Preface: MENU-2019, the 15th International Conference on Meson-Nucleon Physics and the Structure of the Nucleon
In the first part I briefly survey recent issues in constituent quark models raised by the observation of unusual hadronic states. In particular I discuss the role of higher Fock components in the wave function of baryons and the possible interpretation of open charm and of new charmonium-type resonances as tetraquarks. In the second part I show support for the quark model dynamics obtained in a model independent way from the 1/Nc expansion approach of QCD which proved to be successful in describing baryon properties.
On the existence of heavy tetraquarks
Previous work done in collaboration with David Brink is reviewed in the light of the recent observation of new charmonium-like resonances which can be interpreted as tetraquarks. In the framework of a schematic quark model the spectrum of ccqq tetraquarks is presented. 1 e-mail: fstancu@ulg.ac.be
Direct orbital manometry in patients with thyroid-associated orbitopathy.
PURPOSE
To determine orbital tissue tension and orbital compartment compliance in patients with and without thyroid-associated orbitopathy (TAO).


DESIGN
Prospective case series.


PARTICIPANTS
Orbits of patients with TAO (18 orbits) and control patients without TAO (35 orbits) were studied.


METHODS
An orbital manometer was designed to directly measure orbital tissue tension in patients undergoing ocular or orbital surgery.


MAIN OUTCOME MEASURES
Tissue tension was recorded before, during, and for 5 minutes after a 5-ml retrobulbar injection of anesthetic. Orbital compliance was calculated as change in volume divided by change in tissue tension.


RESULTS
Resting orbital tissue tension was 4.4 +/- 2.2 mmHg (mean +/- SD) in normal orbits and 9.7 +/- 4.8 mmHg in orbits of TAO patients (P = 0.0005) Following retrobulbar injection, orbital tissue tension rose to 12.0 +/- 3.6 mmHg (P = 0.0000000000000006 compared with baseline) in the control group and to 36.3 +/- 15.2 mmHg in the TAO group (P = 0.0000007 compared with baseline, and P = 0.000008 TAO group versus control group). Orbital compartment compliance was 0.80 +/- 0.50 ml/mmHg in the control group and 0.27 +/- 0.21 ml/mmHg in the TAO group (P = 0.00001). Resting orbital tissue tension in 8 TAO orbits with compressive optic neuropathy was 12.4 +/- 4.9 mmHg, and was 7.8 +/- 3.5 mmHg in 10 orbits of TAO patients without compressive optic neuropathy (P < 0.05). No adverse events occurred.


CONCLUSIONS
Retrobulbar injection causes consistent measurable changes in orbital tissue tension. Orbital manometry safely demonstrated higher orbital tissue tension and lower orbital compartment compliance in the orbits of TAO patients versus those of normal subjects. Resting orbital tissue tension was higher in the orbits of TAO patients with compressive optic neuropathy than in those orbits without. Compressive optic neuropathy may partially result from an orbital compartment syndrome in some patients with TAO. Directly assessing orbital dynamics in vivo may prove useful as an adjunct in the clinical evaluation of patients with TAO and other orbital disorders.