[Abstract] Objective To investigate the clinical significance of ocular surface examination in diabetic patients with ocular lesions. Methods Ocular surface examination was performed and statistically analyzed in 40 (80 eyes) diabetic consultation cases. Results Thirty-three of 40 patients (82.5%) had subjective symptoms of dry eye, 68 eyes (85%) had tear film rupture time less than 10 s, and 67 eyes (83.75%) had tear secretion test less than 10 mm. 15 eyes (18.75%) had corneal epithelial staining. Conclusion The addition of ocular surface examination items during the ophthalmologic examination of diabetic patients can help in the early detection of lesions of the corneoconjunctival epithelium caused by diabetes mellitus.
In clinical work, all systemic diseases may show certain signs and symptoms in the eyes, and the ocular manifestations also play a role in guiding the diagnosis and treatment of various diseases. From January 1, 2008 to January 31, 2008, our department has conducted 95 cases of 190 eye consultations, including 40 cases of diabetes mellitus and 80 eyes, accounting for 42.11%, which are reported as follows.
1. Clinical data
General data: The diabetic patients in the observation group came from the endocrinology department in 29 cases and 58 eyes, accounting for 72.50%, and from other departments in 11 cases and 22 eyes, accounting for 27.50%. Among them, 21 cases were male and 19 cases were female, with an average age of 61.33±11.54 years. In the healthy control group, there were 25 cases and 50 eyes, 12 cases and 24 eyes in males and 13 cases and 26 eyes in females. The mean age of the control group was 52.08±8.81 years.
Sample exclusion criteria: acute ocular infections (including keratoconus caused by external factors, such as foreign bodies, electrophthalmia, etc. ); abnormal eyelid and eye position; ocular surgery; atropine and timothyroxine eye drops within two weeks; patients with severe dry eye .
2. Methods.
2.1 Ask for medical history, check the specialist medical record, and go to the ophthalmology examination room if the patient is mobile, check visual acuity, intraocular pressure, and slit lamp preocular segment examination.
2.2 tear film rupture time (BUT) and tear secretion test (Schirmer Ⅰ).
2.3 Corneal fluorescein staining: the cornea was divided into four quadrants, and each quadrant was scored according to the degree of staining and staining area. Those with no fluorescein staining were considered negative, those with positive fluorescein staining occupying only one quadrant of the cornea or ≤5 staining points were considered (+), those with positive fluorescein staining occupying two quadrants of the cornea or 6-15 staining points were considered (++), those with positive fluorescein staining occupying three quadrants of the cornea or 16-25 (++), fluorescein staining positive in four quadrants of the cornea or ≥26 staining points (++++).
2.4 Conjunctival blot cell method (CIC method). The cellulose acetate film was cut into small pieces of 2X15 mm, and its rough surface was placed on the temporal bulbar conjunctival surface of the study subjects for 2-3 s. The films were fixed in FAA fixative, then stained with PAS and hematoxylin, dehydrated in ethanol, and treated with xylene transparency, and finally observed under a light microscope. Bilateral eye specimens were collected from each study subject.
The indexes analyzed were the degree of squamous metaplasia of the conjunctival epithelium, the density of cupped cells and other change indexes. Squamous metaplasia was graded using the modified Nelson’S classification. To count the density of conjunctival epithelial cupped cells, a micrometer was used to count the number of cupped cells in five high magnification fields at 40× microscopic magnification, and the average was taken. If the levels of the two eyes were different, the level of the severe eye was taken as the count. According to the morphology of conjunctival epithelial cells and the number and distribution of cupped cells, the specimens of blot cytology were graded one by one: Grade 0: small round epithelial cells with large nuclei and a nucleoplasmic ratio of about l/2.
Grade 1: Epithelial cells are large, polygonal, with a small nucleus to nucleoplasm ratio of about 1/3, and the number of cup-shaped cells is reduced but still ovoid with a strong PAS staining. Grade 3: Epithelial cells are large, polygonal, with small, rounded nuclei, and many nuclei are absent. The nucleoplasmic ratio was l/6. Almost no cup-shaped cells could be found.
3.Statistical analysis
The data were analyzed using SPSSIO.0 statistical analysis software. The differences in corneal fluorescence staining, BUT values, Schirmer values and conjunctival impression cytology were examined by two independent samples rank sum test and X2 test, and Spearman rank correlation analysis and multiple linear regression analysis were applied.
4, Results
4.1 Ocular surface complications: 33 of 40 patients (82.50%) in the observation group complained of dryness in both eyes and
The mean tear film rupture time was (4.49±1.95)s; 11 of 25 patients (44.0%) in the control group complained of dryness and foreign body sensation, and the mean tear film rupture time was 6.76±4.11s. The difference between the two was statistically significant (P=0.001), and the tear film rupture time in the observation group was shorter than that in the healthy control group.
There were 52 eyes (65.0%) with Schirmer<5mm in the observation group and 15 eyes (30.0%) with Schirmer<5mm in the control group, X2=15.09, P=0.000 by chi-square test. the Schirmer value of the observation group was 4.48±2.68mm, and the control group was tear secretion value of 6.28±3.65mm. the observation group's Schirmer value was significantly reduced compared to the control group (P=0.001).
4.2 Corneal fluorescein staining: 45 eyes were fluorescein stained in the observation group, with a positive rate of 56.25%, while 13 eyes were stained in the control group, with a positive rate of 26.0%, and the difference between them was highly significant (X2 = 11.39, P=0.001). The positive staining rate in the observation group was higher than that in the control group. The severity of corneal staining was also heavier in the observation group than in the control group, and there were two cases of filiform keratitis in both eyes in the observation group, and the difference between the two groups in terms of the degree of corneal staining control was significant (U = 16.22, P = 0.003). The degree of corneal staining was negatively correlated with the basal tear secretion, the less tear secretion, the more severe the degree of corneal staining.
4.3 Conjunctival blot cytology: the level of squamous metaplasia of conjunctival epithelial cells in the observation group was higher than that in the control group (U=67.38, P=0.000), which showed round epithelial cells with large nuclei in the control group; the epithelial cells in the observation group were large, polygonal, with small nuclei and increased nucleoplasmic ratio. The number of cup-shaped cells per high magnification field was 10.54±8.88 in the observation group and 41.72±29.38 in the control group, and the number of cup-shaped cells in the observation group was significantly less than that in the control group (P=0.000).
5. Discussion
In the past, the vast majority of diabetic patients were examined for the purpose of examining the fundus of the patient, and ophthalmologists paid more attention to diabetic retinopathy and diabetic cataract, but not enough attention was paid to diabetic-induced corneal conjunctival epitheliopathy. In addition to examining the fundus, we also observed corneal and tear film changes in the diabetic patients who came to our consultation.
The mean value of BUT in our observation group was 4.67±2.31s. 52 eyes (65.0%) had Schirmer I test <5mm, and the mean value of Schirmer I test was (4.48±2.68) mm. 33 cases complained of dry eye symptoms. Many studies at home and abroad have concluded that the corneal sensitivity, BUT value and Schirmer Ⅰ test value of diabetic patients are lower than those of non-diabetic patients in the same age group, that is, the basic tear secretion of diabetic patients is reduced and the stability of the tear film is decreased, considering that the mechanism may be that the afferent pathway of the lacrimal reflex is blocked due to the impairment of corneal sensory nerves in the high glucose state.
The positive staining rate in the observation group was higher than that in the control group, and the severity of corneal staining was also heavier than that in the control group. The cases selected for this paper were all under 65 years of age to reduce the error caused by the decrease in tear secretion with age. It is well documented that diabetes mellitus damages the structure and function of the corneal epithelium and that high glucose status plays a key role. The role of diabetes in the development of corneal epithelial lesions is also multilayered and multifaceted because of the specificity of the corneal epithelium in terms of physiological structure and function as well as nutrient metabolism and repair after injury.
For these patients with subjective symptoms and problematic objective examinations, we have given artificial tears for eye spotting and instructed the patients to follow up in six months.
The etiology of the filiform keratopathy in the 2 eyes of this paper is unclear, and the occurrence of filiform keratopathy has been reported nationally and internationally mainly after excimer laser in situ keratomileusis, while its occurrence in diabetic patients has not been reported. The cause of filiform keratopathy is not well understood and may be related to abnormal proliferation and degeneration of corneal epithelial cells, abnormal tear secretion, and excessive tear mucus formation. Most commonly seen in dry eye disease, viral infection, neurotrophic keratitis, scarring keratoconjunctivitis, in addition to diseases that cause a reduction in transient eyes can also cause the disease.
Foreign pathological studies on diabetic rat corneas have shown that the endothelial cells of the corneas of diabetic rats are swollen, with enlarged gaps and weakened adhesion to the basement membrane. When the epithelium is damaged and shed, it tends to overproliferate, and these cannot be ruled out as the cause of corneal filiform rolls. In these 2 eyes with filamentous keratopathy, there was decreased tear production and decreased corneal perception, as well as a combination of diabetic peripheral neuropathy, so we considered that the filamentous keratopathy was caused by a combination of several factors.
In the DM group, the cytologic examination of the impressions showed that the conjunctival epithelial cells in the DM group had increased squamous metaplasia and decreased the number of cupped cells compared to the control group, and the conjunctival cupped cells, as unicellular mucus glands in the eye, play an important role in maintaining ocular surface stability, lubrication and protection of the ocular surface.
In this study, in addition to examining the retina and lens, the ocular surface of diabetic patients in the in-hospital consultation was also examined, and the results showed that diabetic patients have some degree of ocular surface lesions, so it is necessary to advocate attention to ocular surface and tear film changes during the ophthalmology consultation to reduce ocular surface complications in diabetic patients.