Effect of the Covid-19 Pandemic on Progression to Glaucoma Surgery in Patients Followed Up in a Retina Unit

doi:10.21203/rs.3.rs-1300397/v1

Download PDF

Research Article

Effect of the Covid-19 Pandemic on Progression to Glaucoma Surgery in Patients Followed Up in a Retina Unit

https://doi.org/10.21203/rs.3.rs-1300397/v1

This work is licensed under a CC BY 4.0 License

Version 1

posted

You are reading this latest preprint version

Introduction

In this study, we aimed to investigate the effect of the COVID-19 on progression to glaucoma surgery in patients followed up at the retina unit of the Ophthalmology Outpatient Clinic of Health Sciences University Antalya Training and Research Hospital.

Methods

The patients who were followed up at the retina unit of our hospital. The patients were divided into four groups. This study was retrospective.

Results

The ratio of the number of patients who underwent glaucoma surgery to the number of those presenting to the retina unit was found to be statistically significantly increased in Group 4 compared to the remaining three groups (p<0.0001 for all). The ratio of the number of patients who were followed up in the retina unit and underwent surgery due to neovascular or silicone oil-induced glaucoma to the total number of patients who presented to the retina unit was statistically significantly increased in Group 4 compared to Groups 1 and 2 (p=0.001 for both).

Conclusion

This study is the first to examine the effect of the COVID-19 pandemic on progression to glaucoma surgery in patients followed up at the retina unit. We found an increase in the number of patients that required surgery for neovascular or silicone oil-induced glaucoma compared to previous years as a result of not attending regular follow-up at the retina unit due to COVID-19. We consider that inability to apply timely treatments due to the pandemic conditions are effective in this situation.

COVID-19

glaucoma

retina

silicone oil-induced glaucoma

neovascular glaucoma

Coronavirus disease 2019 (COVID-19) is a systemic disease that affects the whole body, especially the respiratory tract. This disease has affected hundreds of countries around the world and has been declared a pandemic by the World Health Organization [1]. The first case in Turkey was detected on March 11, 2020. Paying attention to personal hygiene, hand washing, wearing a mask, and social distancing are recommended to prevent the spread of the disease. In addition, lockdowns and home quarantine have been implemented in Turkey, as well as in many countries in the world. The necessity of social isolation created by the pandemic and lockdowns have caused a decrease in the rate of hospital visits. It has been observed that even patients who needed regular follow-up have delayed their hospital visits due to the pandemic [2, 3].

In the functioning of outpatient clinics providing care for patients with eye diseases, there are different units, such as retina, glaucoma, cornea, strabismus, oculoplasty, contact lens, and uvea. Most patients need regular follow-up in the retina unit [4].

In this study, we aimed to investigate the effect of the COVID-19 pandemic on progression to glaucoma surgery in patients followed up at the retina unit of the Ophthalmology Outpatient Clinic of Health Sciences University Antalya Training and Research Hospital.

Patient Selection

In this study, patients who were followed up at the retina unit of the Ophthalmology Clinic of Health Sciences University Antalya Training and Research Hospital between March 11, 2018 and March 11, 2021 were retrospectively evaluated. The patients who presented to the retina unit and underwent glaucoma surgery were evaluated in four periods as Group 1, March 11, 2019-September 11, 2019; Group 2, September 12, 2019-March 11, 2020; Group 3, March 12, 2020-September 11, 2020; and Group 4, September 12, 2020-March 11, 2021, and patient ratios were compared between these periods. The first case in Turkey being reported on March 11, 2021, increased lockdown measures being implemented for the first six months, and people’s greater fear of contracting the virus were effective in determining these periods.

The detailed ophthalmological examination and retinal examination files of all the patients were reviewed. The best-corrected visual acuity (BCVA) values of the patients before and after glaucoma surgery were measured using the Early Treatment Diabetic Retinopathy Scale (ETDRS) chart. The decimal system was used to analyze visual acuities. The intraocular pressures of the patients before and after glaucoma surgery were measured with a non-contact tonometer (Nidek NT-2000 NCT, Nidek CO., LTD., Hiroishi Gamagori, Aichi, Japan). For the periods mentioned above, it was determined how many patients presented to the retina unit, how many of these patients underwent glaucoma surgery, and how many glaucoma operations were performed in the clinic. The cases that were followed up at the retina unit and progressed to glaucoma surgery were examined in two groups: silicone oil-induced glaucoma and neovascular glaucoma. Silicone oil-induced glaucoma was primarily treated with silicone tamponade removal and anti-glaucomatous treatment. In neovascular glaucoma, first anti-vascular endothelial growth factor intravitreal injection, panretinal photocoagulation, and anti-glaucomatous treatment were applied. In other glaucoma cases, anti-glaucomatous treatment was primarily applied. In patients whose intraocular pressure did not decrease despite treatments, standard trabeculectomy or Ahmed glaucoma valve surgery was performed under local anesthesia.

This study was approved by University of Health Sciences, Antalya Education and Research Hospital Ethics Committee.

Statistical Analysis

Descriptive statistics were presented as mean, standard deviation, and ratio values. The two-proportion z-test was used to compare the ratios between two groups. The relationship between numerical variables was examined with the Spearman correlation test. The analysis of the data was performed using SPSS v. 23.0 software package program. P values of <0.05 were considered statistically significant.

Table 1 presents the distribution of the number of patients who presented to the retina unit of our hospital and the number of those who underwent glaucoma surgery according to the groups in terms of their demographic characteristics.

Table 1

Demographic characteristics of the patients
Variable	Group 1	Group 2	Group 3	Group 4
Number of patients presenting to the retina unit	4,477	5,356	1,936	1,946
Female/male ratio in glaucoma surgery	1/7	4/6	0/1	5/14
Mean age in glaucoma surgery (mean ± SD)	62.50 ± 7.80	60.50 ± 12.57	40	59.10 ± 12.19
Number of glaucoma operations performed	8	10	1	19
Number of patients with neovascular glaucoma	1	3	0	7
Number of patients with silicone oil-induced glaucoma	2	1	0	8
SD: Standard deviation

The glaucoma classification of the patients who underwent glaucoma surgery is shown in Table 2. Neovascular glaucoma developed due to ischemic central retinal vein occlusion in one patient in Group 1, diabetic retinopathy in two patients and ischemic central retinal vein occlusion in one patient in Group 2, and diabetic retinopathy in five patients and ischemic retinal vein occlusion in two patients in Group 4.

Table 2

Glaucoma classification of the patients undergoing glaucoma surgery
Type of glaucoma	Group 1	Group 2	Group 3	Group 4
Primary open angle glaucoma	3	4	0	2
Primary angle closure glaucoma	0	0	1	1
Pseudoexfoliative glaucoma	0	1	0	0
Uveitic glaucoma	0	1	0	0
Iridocorneal endothelial syndrome	1	0	0	1
Silicone oil-induced glaucoma	2	1	0	8
Neovascular glaucoma	1	3	0	7
Total	8	10	1	19

A total of 38 glaucoma operations were performed in four groups. Of the 38 individuals that underwent glaucoma surgery, 28 were women and 10 were men. The mean age was 59.68 ± 11.61 years, with the mean age of women and men being calculated as 53.60 ± 10.65 and 61.85 ± 11.32, respectively. Trabeculectomy was applied to 35 patients. An Ahmed glaucoma valve was inserted in one patient with neovascular glaucoma in Group 4 who had a history of trabeculectomy surgery in another center three years earlier and was observed to have developed filtration failure during his current examination. One patient with uveitic glaucoma in Group 2 and one patient with neovascular glaucoma in Group 4 required re-glaucoma surgery after trabeculectomy. In these patients, an Ahmed glaucoma valve was placed, but their second surgery was not included in the data. Table 3 shows the mean preoperative BCVA, postoperative BCVA, preoperative intraocular pressure, postoperative intraocular pressure, follow-up time, number of intravitreal injections in cases of neovascular glaucoma, and duration of silicone tamponade stay in the eye in cases of silicone oil-induced glaucoma according to the study groups.

Table 3

Distribution of the characteristics of patients who underwent glaucoma surgery according to study groups
Variable	Group 1 (Mean ± SD)	Group 2 (Mean ± SD)	Group 3 (Mean ± SD)	Group 4 (Mean ± SD)
Number of patients	8	10	1	19
Age	62.52 ± 7.80	60.50 ± 12.57	40	59.10 ± 12.19
Preoperative BCVA	0.14 ± 0.16	0.13 ± 0.15	0.20	0.07 ± 0.11
Postoperative BCVA	0.19 ± 0.20	0.20 ± 0.19	0.40	0.10 ± 0.15
Preoperative IOP	31.63 ± 5.32	35.20 ± 5.33	35	38.42 ± 6.83
Postoperative IOP	17.25 ± 2.82	15.20 ± 2.20	16	15.95 ± 4.21
Follow-up time (months)	44.13 ± 13.74	38.40 ± 16.18	16	26.74 ± 18.61
Number of intravitreal injections	8	13.66 ± 6.02	0	7.14 ± 4.91
Duration of silicone tamponade stay (months)	11 ± 2.82	12	0	23 ± 4.56
BCVA: Best-corrected visual acuity, IOP: Intraocular pressure, SD: Standard deviation

The number of patients presenting to the retinal unit was statistically significantly decreased in Group 3 compared to Groups 1 and 2 (p < 0.0001 for both). In addition, the number of patients who presented to the retina unit was statistically significantly decreased in in Group 4 compared to Groups 1 and 2 (p < 0.0001 for both).

Table 4 shows the comparison of the ratio of the number of patients who underwent glaucoma surgery to the total number of patients who presented to the retina unit between the study groups. There was no statistically significant difference in this ratio between Group 1 and Group 3 (p = 0.06). However, this ratio was statistically significantly decreased in Group 3 compared to Group 2 (p = 0.042). A statistically significant increase was observed in this ratio in Group 4 when compared to the remaining three groups (p < 0.0001 for all).

Table 4

Distribution of the ratio of the number of patients who underwent glaucoma surgery to the total number of patients presenting to the retina unit according to the study groups
Variable	Group 1	Group 2	Group 3	Group 4	P value
G/R	8/4,477		1/1,936		0.06
G/R		10/5,356	1/1,936		0.042
G/R	8/4,477			19/1,946	<0.0001
G/R		10/5,356		19/1,946	<0.0001
G/R			1/1,936	19/1,946	<0.0001

G/R: Ratio of the number of patients that underwent glaucoma surgery to the total number of patients that presented to the retina unit

Table 5 presents the comparison of the ratio of the number of patients followed up in the retina unit who underwent glaucoma surgery due to neovascular or silicon oil-induced glaucoma to the total number of patients that presented to the retina unit between the groups. This ratio was statistically significantly increased in Group 4 when compared to Groups 1 and 2 (p = 0.001 for both).

Table 5

Comparison of the ratio of the number of patients who were followed up in the retina unit and underwent glaucoma surgery to the total number of patients who presented to the retina unit between the study groups
Variable	Group 1	Group 2	Group 4	P value
RG/R	3/4,477		15/1,946	0.001
RG/R		4/5,356	15/1,946	0.001

RG/R: ratio of the number of patients followed up in the retina unit who underwent glaucoma surgery (neovascular or silicon oil-induced glaucoma) to the total number of patients that presented to the retina unit

Table 6 shows the comparison of the ratio of the number of patients followed up in the retina unit who underwent glaucoma surgery (neovascular or silicon oil-induced glaucoma) to the total number of patients who underwent glaucoma surgery between the study groups. There statistically significant increase in this ratio in Group 4 when compared to Groups 1 and 2 (p = 0.017 and p = 0.031, respectively).

Table 6

Comparison of the ratio of the number of patients followed up in the retina unit who underwent glaucoma surgery to the total number of patients who underwent glaucoma surgery between the study groups
Variable	Group 1	Group 2	Group 4	P value
RG/G	3/8		15/19	0.017
RG/G		4/10	15/19	0.031
RG/T: ratio of the number of patients followed up in the retina unit who underwent glaucoma surgery to the total number of patients who underwent glaucoma surgery

In patients with silicone oil-induced glaucoma, a negative correlation was detected between the duration of silicone tamponade stay and preoperative BCVA (r = -0.383, p = 0.18). In addition, there was a negative correlation between the duration of silicone tamponade stay and postoperative BCVA in the same patients (r = -0.413, p = 0.10).

COVID-19 is a systemic disease that causes symptoms throughout the body. The general symptoms of COVID-19 include cough, fever, sore throat, fatigue, headache, loss of taste, loss of smell, lower back pain, and muscle pain. This disease, transmitted through droplets, has led to a global pandemic [5]. The first case in Turkey was detected on March 11, 2020. To prevent the spread of the disease, paying attention to personal hygiene, hand washing, wearing a mask, and social isolation have been recommended [3, 6].

Many countries in the world have had to resort to additional measures to tackle the COVID-19 pandemic, with the virus spreading rapidly, infecting many people, and resulting in millions of deaths. In Turkey, various measures have been implemented, including lockdowns, home quarantine, closure of shopping centers, reduction of public transportation use, closure of certain workplaces, and transition to home office working. Both the necessity of social isolation caused by the fear of contracting the virus and implemented lockdowns have resulted in a decrease in the rates of hospital visits [6, 7].

Units operating under ophthalmology outpatient clinics can be listed as cornea, uvea, glaucoma, retina, contact lens, strabismus, and oculoplasty [4]. Among these units, the retina unit follows up patients diagnosed with retinal detachment, vitreous hemorrhage, epiretinal membrane, and macular holes, as well as those that have undergone vitreoretinal surgery due to retinal vascular diseases, such as diabetic retinopathy, retinal vein occlusion, retinal artery occlusion, and ocular ischemic syndrome. These patients should attends regular follow-up every three to six months. In patients with retinal vascular disease without follow-up, neovascularization may occur in the retina, and as a result neovascular glaucoma may develop [8–10]. If patients who have undergone vitreoretinal surgery and have had silicone tamponade inserted into the eye are not followed up regularly, and thus their silicone tamponade is not removed when necessary, it may emulsify over time and cause glaucoma by obstructing the trabecular meshwork [11–12].

Trabeculectomy is the gold standard surgical treatment in patients with glaucoma. This surgery aims to reduce intraocular pressure by creating a fistula between the subconjunctival area and the anterior chamber [13, 14]. The Ahmed glaucoma valve is a drainage device that uses a venturi valve mechanism to control excessive aqueous drainage into the posterior episcleral or subconjunctival area. It allows the aqueous to flow slowly through a chamber, and when intraocular pressure reaches the threshold value, the valve allows the fluid to exit the silicone tube, thus lowering intraocular pressure [15, 16].

In this study, we found a decrease in the total number of patients who presented to the retina unit and underwent glaucoma surgery in Group 3 compared to Groups 1 and 2. In addition, there was a decrease in the number of patients presenting to the retina unit in Group 4 compared to Groups 1 and 2. This decrease was due to the patients not attending their regular follow-up. We consider that the fear of contracting COVID-19 and dying, restrictions implemented to prevent the spread of the virus, and need for social isolation are effective in this situation.

Although the number of patients who presented to our retina unit was statistically significantly decreased in Group 4 compared to Groups 1 and 2, the number of those that underwent glaucoma surgery was higher. The ratio of the number of patients that underwent glaucoma surgery to the total number of those presenting to the retinal unit was statistically significantly higher in Group 4 than all the remaining groups. The number of glaucoma operations being higher in Group 4 compared to the remaining groups may be because many patients did not attend their necessary follow-up after March 11, 2020, when the first case of COVID-19 was reported in Turkey, and therefore they were not able to undergo timely interventions, such as anti-glaucomatous treatment, intravitreal injections, argon laser photocoagulation, and removal of silicone tamponade.

In Group 4, 42.10% (8/19) of the glaucoma operations were due to neovascular glaucoma and 36.84% (7/19) were due to silicone oil occluding the trabecular meshwork. The ratio of the number of patients who underwent glaucoma surgery due to neovascular glaucoma and silicon oil-induced glaucoma to the total number of patients who underwent glaucoma surgery, and the ratio of the number of patients who underwent glaucoma surgery due to neovascular glaucoma and silicon oil-induced glaucoma to the total number of patients who presented to the retina unit were statistically significantly higher in Group 4 compared to Groups 1 and 2. We consider that the increase in the number of patients with neovascular glaucoma may be due to the patients with retinal vascular disease not receiving intravitreal injections, argon laser photocoagulation, and anti-glaucomatous drug therapy on time because they did not attend their follow-up. Similarly, the increase in the number of patients with silicone oil-induced glaucoma is probably because the patients who had undergone vitreoretinal surgery did not attend follow-up and did not realize that the silicone had emulsified, and therefore they did not receive anti-glaucomatous and silicone removal treatment in a timely manner.

Although studies in the literature suggest that the main cause of silicone oil-induced glaucoma is the emulsification of the silicone, it has been stated that the duration of silicone tamponade stay in the eye may also be effective in the development of glaucoma. It has been shown that as the duration of silicone stay in the eye increases, the rate of emulsified silicone increases, and accordingly there is a greater possibility of glaucoma development due to various reasons, such as silicone transfer to the anterior chamber, angle closure, and rubeosis iridis [17]. The development of silicone oil-induced glaucoma occurs after an average of five to 24 months postoperatively [18]. However, it has also been reported that silicone oil-induced glaucoma can occur even in the postoperative first month [19]. It has also been determined that the decrease in postoperative BCVA is associated with the duration of silicone tamponade stay in the eye [20].

Similar to the above-mentioned studies, we found that the duration of silicone tamponade stay in the eye had a negative correlation with the preoperative and postoperative BCVA values of the patients who underwent glaucoma surgery due to silicone oil-induced glaucoma. Accordingly, the preoperative and postoperative BCVA values decreased as the duration of silicone stay increased. The longer the silicone remains in the eye, the higher the emulsification rate, resulting in glaucoma and eventually retinal nerve fiber and vision loss. In our study, the mean duration of silicone tamponade stay was significantly longer significantly in Group 4 compared to the remaining groups, which was attributed to the patients not visiting the hospital for their follow-up due to the pandemic.

This study is the first to examine the effect of the COVID-19 pandemic on progression to glaucoma surgery in patients followed up at the retina unit. The COVID-19 pandemic has had negative effects on various aspects of life. In this study, we detected an increase in the number of patients with neovascular glaucoma and silicone oil-induced glaucoma, and those undergoing glaucoma surgery among the patients that had not attended their regular follow-up in the retina unit due to the pandemic. We consider that the fear of contracting the virus, implemented lockdowns, need for social isolation, and inability to apply timely treatments due to the pandemic conditions are effective in this situation.

Funding No funding was received for conducting this study.

Conflict of interest All authors declare no funding was received and no conflict of interest/competing interests.

Data availability The data supporting the findings of the study are available from the corresponding author upon request.

Code availability Not applicable.

Authors’ contributions All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by MKE, BG, ES and MA. The first draft of the manuscript was written by BG and SY. MKE, BD, FD and EBT read, revised, and approved the final manuscript.

Ethical approval The study protocol was approved by the Health Sciences University Antalya Training And Research Hospital (Date: 10.06.21 No:8/5). This article does not contain any studies with human participants or animals performed by any of the authors.

Consent to participate Written consent was acquired by all participants.

Consent for publication Written consent was acquired by all participants.

Lu R, Zhao X, Li J et al (2020) Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding. Lancet 395(10224):565–574. https://doi.org/10.1016/S0140-6736(20)30251-8
Hamroush A, Qureshi M, Shah S (2020) Increased risk of ocular injury seen during lockdown due to COVID-19. Contact Lens Anterior Eye 43(3):216. https://doi.org/10.1016/j.clae.2020.04.007
Lotfi M, Hamblin MR, Rezaei N (2020) COVID-19: Transmission, prevention, and potential therapeutic opportunities. Clin Chim Acta 508:254–266. https://doi.org/10.1016/j.cca.2020.05.044
Bayramlar H, Karadag R, Gurturk AYK et al (2015) Publication Patterns of Ophthalmology Residency Dissertations in Turkey. Eur J Gen Med. 12(3):213-216. https://doi.org/10.15197/sabad.1.12.45
Wiersinga WJ, Rhodes A, Cheng AC et al (2020) Pathophysiology, Transmission, Diagnosis, and Treatment of Coronavirus Disease 2019 (COVID-19): A Review. JAMA - J Am Med Assoc 324(8):782–793. https://doi.org/10.1001/jama.2020.12839
Akdeniz G, Kavakci M, Gozugok M et al (2020) A Survey of Attitudes, Anxiety Status, and Protective Behaviors of the University Students During the COVID-19 Outbreak in Turkey. Front Psychiatry 11:695. https://doi.org/10.3389/fpsyt.2020.00695
Ogutlu H (2020) Turkey’s Response to COVID-19 in Terms of Mental Health. Irish Journal of Psychological Medicine 37(3):222–225. https://doi.org/10.1017/ipm.2020.57
Al-Bahlal A, Khandekar R, Rubaie KA et al (2017) Changing epidemiology of neovascular glaucoma from 2002 to 2012 at King Khaled Eye Specialist Hospital, Saudi Arabia. Indian J Ophthalmol 65(10):969–973. https://doi.org/10.4103/ijo.IJO_33_17
Ha JY, Lee TH, Sung MS, Park SW (2017) Efficacy and Safety of Intracameral Bevacizumab for Treatment of Neovascular Glaucoma. Korean J Ophthalmol 31(6):538–547
Sarireh FA, Alrawashdeh HM, Zubi KA, Salem KA (2021) Role of bevacizumab intraocular injection in the management of neovascular glaucoma. Int J Ophthalmol 14(6):855–859. https://doi.org/10.18240/ijo.2021.06.10
Abdullah A (2020) Outcome of Surgical Management of Glaucoma Following Complex Retinal Detachment Repair With Silicone Oil Tamponade: Drainage Implant Versus Cyclophotocoagulation. Journal of Glaucoma 29:198–204 RizwanMRajiv K
Bhoot M, Agarwal A, Dubey S et al (2018) Silicone Oil Induced Glaucoma. Delhi Journal of Ophthalmology 29:9–13
Taiki K, Satoru T, Hiroshi K et al (2018) Prediction of Surgical Outcome After Trabeculectomy for Neovascular Glaucoma With Anterior-segment Optical Coherence Tomography. Journal of Glaucoma 27:1157–1164
Guo X, Wang Y, Yang L et al (2021) Comparison of conbercept and ranibizumab combined mitomycin C-augmented trabeculectomy for neovascular glaucoma. Int Ophthalmol 41:2869–2877
Xie Z, Liu H, Du M et al (2019) Efficacy of Ahmed Glaucoma Valve Implantation on Neovascular Glaucoma. Int J Med Sci 16(10):1371–1376
He Y, Tian Y, Song W et al (2017) Efficacy analysis of Ahmed glaucoma valve implantation in neovascular glaucoma and influencing factors: A STROBE-compliant article. Medicine 96(42):e8350. https://doi.org/10.1097/MD.0000000000008350
Branisteanu DC, Moraru AD, Maranduca MA et al (2020) Intraocular pressure changes during and after silicone oil endotamponade (Review). Experimental and Therapeutic Medicine 20(6):204. https://doi.org/10.3892/etm.2020.9334
Toklu Y, Cakmak HB, Ergun SB et al (2012) Time course of silicone oil emulsification. Retina 32:2039–2044
Ratanapakorn T, Thongmee W, Meethongkam K et al (2020) Emulsification of different viscosity silicone oil in complicated retinal detachment surgery: A randomized double-blinded clinical trial. Clin Ophthalmol 14:359–367. https://doi.org/10.2147/OPTH.S242804
Scheerlinck LM, Schellekens PA, Liem AT et al (2016) Incidence, Risk Factors, and Clinical Characteristics of Unexplained Visual Loss after Intraocular Silicone Oil for Macula-on Retinal Detachment. Retina 36:342–350

Download PDF

Version 1

posted

You are reading this latest preprint version

Effect of the Covid-19 Pandemic on Progression to Glaucoma Surgery in Patients Followed Up in a Retina Unit

Status:

Version 1

Abstract

Introduction

Methods

Patient Selection

Statistical Analysis

Results

Discussion

Conclusion

Declarations

References

Status:

Version 1