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Diffusion tensor magnetic resonance imaging of trigeminal nerves in relapsing herpetic keratouveitis.

Rousseau A, Nasser G, Chiquet C, Barreau E, Gendron G, Kaswin G, M'Garrech M, Benoudiba F, Ducreux D, Labetoulle M - PLoS ONE (2015)

Bottom Line: FA was lower in the trigeminal fibers ipsilateral to the affected eye compared to the non-affected side (0.39±0.02 versus 0.46±0.04, P=0.03).Concomitantly, the asymmetry in ADC results was significantly correlated with the loss of corneal sensitivity in the affected eye.These results add further explanation to the pathogenesis of HSV and VZV-induced neurotrophic keratitis, which may occur despite an apparent quiescence of the disease.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Bicêtre Hospital, Assistance Publique-Hôpitaux de Paris, Paris-Sud University, Le Kremlin-Bicêtre, France.

ABSTRACT

Background: Corneal hypoesthesia is the landmark of HSV and VZV keratitis and can lead to neurotrophic keratitis. Diffusion tensor imaging (DTI) is a new magnetic resonance imaging (MRI) derived technique, which offers possibilities to study axonal architecture. We aimed at assessing the potential impact of recurrent HSV or VZV-related keratitis on the axonal architecture of trigeminal nerves using DTI.

Design: Prospective non-interventional study.

Participants: Twelve patients and 24 controls.

Methods: DTI using MRI of the trigeminal fibers and corneal esthesiometry using the Cochet-Bonnet esthesiometer were acquired for patients affected by unilateral and recurrent HSV or VZV-related keratitis (3 months after the last corneal inflammatory event), and control subjects with no history of ocular or neuronal disease affecting the trigeminal pathways.

Main outcome measures: Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were compared between the 2 eyes of both patients and controls, and correlated with corneal esthesiometry.

Results: FA was lower in the trigeminal fibers ipsilateral to the affected eye compared to the non-affected side (0.39±0.02 versus 0.46±0.04, P=0.03). This difference was more important than the intra-individual variability observed in controls. Concomitantly, the asymmetry in ADC results was significantly correlated with the loss of corneal sensitivity in the affected eye.

Conclusions: Corneal hypoesthesia related to HSV and VZV keratitis is associated with persistent modifications in the architecture and functionality of the trigeminal fibers. These results add further explanation to the pathogenesis of HSV and VZV-induced neurotrophic keratitis, which may occur despite an apparent quiescence of the disease.

No MeSH data available.


Related in: MedlinePlus

Asymmetry in the corneal sensitivity (affected eye minus non-affected eye) as a function of the asymmetry in apparent diffusion coefficient (ADC) results (higher value minus lower value) in patients with a proven or strongly presumed keratitis or keratouveitis related to either HSV or VZV.The solid line indicates the significant correlation between results (Spearman test, P = 0.05).
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pone.0122186.g004: Asymmetry in the corneal sensitivity (affected eye minus non-affected eye) as a function of the asymmetry in apparent diffusion coefficient (ADC) results (higher value minus lower value) in patients with a proven or strongly presumed keratitis or keratouveitis related to either HSV or VZV.The solid line indicates the significant correlation between results (Spearman test, P = 0.05).

Mentions: The results of DTI, performed with a mean delay of 26.6±17.7 months after the last acute ocular episode in the keratitis group, are summarized in Table 2 (details in Tables 3 and 4). In the control group, there was no significant difference between the right and the left trigeminal pathways concerning the FA values (0.40±0.03 versus 0.39±0.02, P = 0.57) and the ADC results (1.69±0.10 vs 1.66±0.09, P = 0.68). In contrast, in the keratitis group, the FA results were significantly lower in the trigeminal fibers ipsilateral to the affected eye than in those of the non-affected side (0.39±0.02 versus 0.46±0.04, P = 0.03) (Fig. 2). Moreover, the asymmetry between the affected and non-affected side (mean difference: 0.06±0.03) was significantly more important than the mean difference between all higher and all lower values in control subjects (0.02±0.01, P = 0.02) (Fig. 3). However, such a significant difference between affected and non-affected side was not observed for the ADC values (1.81±0.14 vs 1.72±0.2, P = 0.32), and the mean asymmetry in these patients was comparable to the maximal asymmetry assessed in control subjects (0.1±0.19 vs 0.11±0.03, P = 0.8). Since ADC is known as a marker of the quality of water exchange in the nerve fibers, and thus of their normal physiology, we compared these results with those of the corneal sensitivity, using the CBE. As expected, there was a significant asymmetry between affected versus non-affected eyes (29.6±6.0 mm versus 48.7±4.0 mm, P = 0.0003) in patients presenting a recurrent or severe corneal disease due to HSV or VZV. When the difference in corneal sensitivity was compared to the difference (asymmetry) in FA results, no relationship was observed among the patients, but a significant correlation (P = 0.05, Spearman test) was observed between the loss of corneal sensitivity and the asymmetry in ADC results (Fig. 4).


Diffusion tensor magnetic resonance imaging of trigeminal nerves in relapsing herpetic keratouveitis.

Rousseau A, Nasser G, Chiquet C, Barreau E, Gendron G, Kaswin G, M'Garrech M, Benoudiba F, Ducreux D, Labetoulle M - PLoS ONE (2015)

Asymmetry in the corneal sensitivity (affected eye minus non-affected eye) as a function of the asymmetry in apparent diffusion coefficient (ADC) results (higher value minus lower value) in patients with a proven or strongly presumed keratitis or keratouveitis related to either HSV or VZV.The solid line indicates the significant correlation between results (Spearman test, P = 0.05).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4382307&req=5

pone.0122186.g004: Asymmetry in the corneal sensitivity (affected eye minus non-affected eye) as a function of the asymmetry in apparent diffusion coefficient (ADC) results (higher value minus lower value) in patients with a proven or strongly presumed keratitis or keratouveitis related to either HSV or VZV.The solid line indicates the significant correlation between results (Spearman test, P = 0.05).
Mentions: The results of DTI, performed with a mean delay of 26.6±17.7 months after the last acute ocular episode in the keratitis group, are summarized in Table 2 (details in Tables 3 and 4). In the control group, there was no significant difference between the right and the left trigeminal pathways concerning the FA values (0.40±0.03 versus 0.39±0.02, P = 0.57) and the ADC results (1.69±0.10 vs 1.66±0.09, P = 0.68). In contrast, in the keratitis group, the FA results were significantly lower in the trigeminal fibers ipsilateral to the affected eye than in those of the non-affected side (0.39±0.02 versus 0.46±0.04, P = 0.03) (Fig. 2). Moreover, the asymmetry between the affected and non-affected side (mean difference: 0.06±0.03) was significantly more important than the mean difference between all higher and all lower values in control subjects (0.02±0.01, P = 0.02) (Fig. 3). However, such a significant difference between affected and non-affected side was not observed for the ADC values (1.81±0.14 vs 1.72±0.2, P = 0.32), and the mean asymmetry in these patients was comparable to the maximal asymmetry assessed in control subjects (0.1±0.19 vs 0.11±0.03, P = 0.8). Since ADC is known as a marker of the quality of water exchange in the nerve fibers, and thus of their normal physiology, we compared these results with those of the corneal sensitivity, using the CBE. As expected, there was a significant asymmetry between affected versus non-affected eyes (29.6±6.0 mm versus 48.7±4.0 mm, P = 0.0003) in patients presenting a recurrent or severe corneal disease due to HSV or VZV. When the difference in corneal sensitivity was compared to the difference (asymmetry) in FA results, no relationship was observed among the patients, but a significant correlation (P = 0.05, Spearman test) was observed between the loss of corneal sensitivity and the asymmetry in ADC results (Fig. 4).

Bottom Line: FA was lower in the trigeminal fibers ipsilateral to the affected eye compared to the non-affected side (0.39±0.02 versus 0.46±0.04, P=0.03).Concomitantly, the asymmetry in ADC results was significantly correlated with the loss of corneal sensitivity in the affected eye.These results add further explanation to the pathogenesis of HSV and VZV-induced neurotrophic keratitis, which may occur despite an apparent quiescence of the disease.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Bicêtre Hospital, Assistance Publique-Hôpitaux de Paris, Paris-Sud University, Le Kremlin-Bicêtre, France.

ABSTRACT

Background: Corneal hypoesthesia is the landmark of HSV and VZV keratitis and can lead to neurotrophic keratitis. Diffusion tensor imaging (DTI) is a new magnetic resonance imaging (MRI) derived technique, which offers possibilities to study axonal architecture. We aimed at assessing the potential impact of recurrent HSV or VZV-related keratitis on the axonal architecture of trigeminal nerves using DTI.

Design: Prospective non-interventional study.

Participants: Twelve patients and 24 controls.

Methods: DTI using MRI of the trigeminal fibers and corneal esthesiometry using the Cochet-Bonnet esthesiometer were acquired for patients affected by unilateral and recurrent HSV or VZV-related keratitis (3 months after the last corneal inflammatory event), and control subjects with no history of ocular or neuronal disease affecting the trigeminal pathways.

Main outcome measures: Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were compared between the 2 eyes of both patients and controls, and correlated with corneal esthesiometry.

Results: FA was lower in the trigeminal fibers ipsilateral to the affected eye compared to the non-affected side (0.39±0.02 versus 0.46±0.04, P=0.03). This difference was more important than the intra-individual variability observed in controls. Concomitantly, the asymmetry in ADC results was significantly correlated with the loss of corneal sensitivity in the affected eye.

Conclusions: Corneal hypoesthesia related to HSV and VZV keratitis is associated with persistent modifications in the architecture and functionality of the trigeminal fibers. These results add further explanation to the pathogenesis of HSV and VZV-induced neurotrophic keratitis, which may occur despite an apparent quiescence of the disease.

No MeSH data available.


Related in: MedlinePlus