Franck Fetissof

Very-High-Frequency Ultrasound Corneal Imaging as a New Tool for Early Diagnosis of Ocular Surface Toxicity in Rabbits Treated with a Preserved Glaucoma Drug

Aim: To evaluate very-high-frequency (VHF) ultrasound imaging as a new method to detect and quantify early corneal epithelium changes induced by chronic exposure to a benzalkonium-chloride-containing antiglaucoma drug. Methods: Timolol preserved with 0.01% benzalkonium chloride solution was applied b.i.d. in 1 eye of 10 rabbits for 56 days. Unpreserved timolol solution was used as control. Ocular surface changes were assessed weekly combining clinical examinations, in vivo 60-MHz ultrasound imaging and ex vivo histological analysis. Results: VHF ultrasound imaging allowed quantitative measurement of corneal epithelium thickness and qualitative imaging of toxic epithelial damage. It revealed significantly decreased epithelial thickness in vivo as early as the 21st day of treatment (40.75 ± 1.72 µm at D0 vs. 39 ± 2 at D21, vs. 31.9 ± 2.98 at D56; p = 0.017 and p = 0.005, respectively). The first clinical changes appeared from the 42nd day of treatment (conjunctival redness, conjunctival staining and corneal staining; D56 compared to D0: p = 0.005, 0.01 and 0.004, respectively) and then correlated with VHF ultrasound data. Epithelial thickness measured with VHF ultrasound was correlated with histological epithelial pachymetry (p < 0.001) and with the corneal damage score assessed with scanning electron microscopy (p = 0.038). Conclusion: VHF ultrasound imaging provided an early in vivo diagnosis of corneal epithelium pathology induced by chronic exposure to a preserved glaucoma drug, before the first clinical evidence of ocular toxicity. It could be a new reproducible method to detect the toxicity of glaucoma medication so that therapy can then be adapted.

ARGYROPHILIC CELLS AND ECTOCERVICAL EPITHELIUM

Summary:The purpose of this study was to determine the nature of the argyrophilic cells in the ectocervix and to analyze the different morphologic varieties of argyrophil cell-containing ectocervical epithelia, notably to reappraise the degree of analogy with transitional epithelium. A systematic study of 39 ectocervices was carried out using histochemical and immunohistochemical techniques. Immunodetection of cytokeratins was used to specify the differentiation of the ectocervical linings. Argyrophilic cells were detected in 43% of our specimens. They have been found in several varieties of ectocervical lining: normal-appearing or hyperkeratotic squamous epithelium, “transitional-like” epithelium extending onto the portio, and immature squamous metaplasia from the transformation zone. The term “transitional-like” refers to a stratified nonsquamous epithelium that differs from true urothelium by the absence of superficial differentiation leading to the layer of “umbrella” cells. Two main types of argyrophilic cells have been delineated: serotonin cells and Merkel-type cells. The nature of the argyrophilic cells was dependent on the type of epithelium: Serotonin cells were essentially associated with “transitional-like” epithelium and Merkel-type cells with squamous epithelium. The latter cells were particularly frequent in hyperkeratotic squamous epithelium from uterine prolapse, reinforcing the homology with epidermis.

Contractile and relaxant properties of rat‐isolated pulmonary veins related to localization and histology

The aim of this study was to investigate the in vitro vasomotor properties of rat extra‐and intralobar pulmonary veins (PVs) related to their localization and to assess the modulatory role of endothelium on these properties. Segments from PVs were mounted in small vessel myograph and stretched at various diameters (D10, D20, D30) corresponding to intraluminal pressures of 10, 20 or 30u2003mmHg. At D10 or D20, contractile responses to phenylephrine, U46619 and angiotensin II of distal intralobar part of PVs were smaller compared with those of proximal extralobar part, but no longer different when distal part was stretched at D30. When submitted to an NO donor, sodium nitroprusside, distal part of PV relaxed more strongly when stretched at D30 compared with D10. Acetylcholine and bradykinin were devoid of relaxing effect on distal parts stretched at D10, but in contrast to acetylcholine, bradykinin slightly relaxed preparations stretched at D30. Isoprenaline strongly relaxed PVs (∼80% of initial precontraction), with the distal part exhibiting a higher sensitivity to the agonist compared with the proximal part. This relaxation was also observed with salbutamol and suppressed with ICI 118551, which is in favour of the involvement of β2‐adrenoceptors in this effect. Preincubation of the preparations with NG‐nitro‐l‐arginine methyl ester (10−4u2003m) and indomethacin (10−5u2003m) did not modify the contractile responses to U46619, nor the relaxing response to isoprenaline, which support that endothelium does not appear to play a significant modulatory role in these responses. Histological and electron microscopical examinations of proximal and distal sections of the same vein show that the layers of smooth muscle cells and cardiomyocytes were thicker in the proximal compared with the distal part. This study shows that, because of morphological heterogeneity of the PVs, the site of dissection and the initial condition of tension can play a significant role upon the sensitivity and the magnitude of the responses to both contractile and relaxing agonists.

Florid marginal zone differentiation in follicular lymphoma mimicking marginal zone lymphoma of MALT type in the lung

Up to 20% of laparoscopic procedures for tubal ectopic pregnancy are associated with persistent trophoblastic tissue. This is usually tubal in origin but cases of implantation of trophoblastic tissue in other intraabdominal sites have been described—usually on pelvic peritoneum. The secondary implantation of trophoblast tissue in omentum is very rare, with only two histologically described cases reported to date. We wish to report the first case of implantation of fetal parts in omentum following laparoscopic salpingectomy for a ruptured ectopic pregnancy. A 36-year-old woman presented with lower abdominal pain at 7 (+ 4) weeks’ gestation. A left ectopic pregnancy and an intrauterine pregnancy were detected on ultrasound scan. On laparoscopy a left ruptured ectopic pregnancy with fetal parts was seen. The left fallopian tube was removed piecemeal. A tubal ectopic pregnancy was confirmed histologically. Ten days later she presented with signs of peritonitis. On laparotomy a congested appendix and an omental mass, initially thought to be a left adnexal abscess, were seen. Both were removed and sent for histological examination. Macroscopically, the appendix showed a congested surface with pus-like organized material seen over the serosal fat. The omentum measured 170 · 60 · 20 mm and showed small areas of organized exudates and lobulated fat. Histologically, the appendix had acute inflammation with fibrinous exudates and fat necrosis on the serosal surface. The omentum showed an infiltrate of acute inflammatory cells and fat necrosis. Two deposits of mature cartilage were seen within the omentum. These were surrounded by immature mesenchymal cells. This was thought to represent a deposit of fetal parts from the previous ruptured ectopic pregnancy (Figure 1). Our case is unique in that fetal parts as opposed to trophoblastic tissue were found in omentum and this probably represents the implantation of fetal parts seen at the time of laparoscopy. Persisting trophoblastic tissue following laparoscopic procedures for tubal ectopic pregnancy can present as haemoperitoneum or peritonitis. This case report illustrates the point that the diagnosis must be suspected in any patient presenting with peritonism following treatment for ectopic pregnancy and a search for persistent tissue must be made.