A clinical analysis of vitrectomy for severe vitreoretinopathy in patients with chronic renal

Thirteen male patients and three female patients aged are involved in this study. The mean age of the patients was 52.9 years (ranged from 32 to 63 years old). Among these patients, 1 of them was in the thirties, 1 of them was in the forties, 11 of them were in their fifties and 3 of them was in their sixties. The course of disease ranged from 4 months to 9 years, with a mean of 3.2 years. Ten patients were on hemodialysis, two patients underwent peritoneal dialysis, and four patients did not have any dialysis. Fourteen patients were combined with DM with an average course of 16.3 years (ranged from 1 to 25 years). All patients were combined with hypertension. The average course of hypertension was 7.5 years (ranged from 0.4 to 15 years, Table 1).

Twelve patients had decreased hemoglobin, five had elevated level of serum potassium, and five had low cardiac function. Sixteen eyes had vitreous hemorrhage, and two were complicated with tractional retinal detachment. All patients were subjected to the following ophthalmic examinations: best corrected visual acuity (BCVA), slit lamp microscopy, mydriatic fundus examination, gonioscopy, A-scan ultrasonography, B-scan ultrasonography, and specular microscopy. The patients also underwent a series of systemic evaluations, including full blood cell count, hepatic and renal function tests, electrolytes, blood glucose, glycosylated hemoglobin measurements, electrocardiography, and echocardiography.

Patients on hemodialysis underwent heparin-free hemodialysis treatment one day before the surgery and repeated within seven days after surgery. They received normal anticoagulant dialysis afterwards. Seven eyes received intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) 0.05 ml (Conbercept, KH902; Chengdu Kanghong Biotech Co., Ltd., Sichuan, China) three days before surgery.

During the operation, patients received retrobulbar injection of anesthesia. Fourteen patients showed an increase of blood pressure after the three scleral cannulas were inserted. They were treated with intravenous infusion of 1 mg midazolam for sedation and 12.5 mg urapidil for blood pressure. During the surgery, nine patients showed the increase of blood pressure, and four of them reached to a peak value of 210/110 mmHg. These patients were treated with an intravenous injection of 12.5 mg urapidil every 15 min, up to four times as needed or intravenous drip of 100 mg urapidil in 250 ml normal saline to maintain the blood pressure below 160/90 mmHg. Two patients showed a blood pressure consistently higher than 200/100 mmHg. The surgery was resumed and completed until the blood pressure was stabilized by intravenous trinitroglycerin.

The surgeries were performed by using Alcon Constellation 25-G vitrectomy machines (Alcon Laboratories, Inc., Fort Worth, TX, USA). After core vitrectomy, the cortical vitreous was stained with triamcinolone acetonide, and removed after the posterior vitreous detachment was created. The electrocoagulation was used for hemostasis. The proliferative epiretinal membrane was dissected to release the tangential traction. These were followed by pan retinal laser photocoagulation. Three eyes were filled with silicone oil due to the inferior retinal breaks. Patients combined with cataract underwent phacoemulsification and hydrophobic intraocular lens implantation. At the end of the surgery, 1 mg triamcinolone acetonide was injected into the vitreous cavity. Follow up examinations including visual acuity, intraocular pressure, slit lamp microscopy, and mydriatic fundus examination,fundus photography and macular OCT were conducted at 1 day,1 week, 4 weeks,and 12 weeks,postoperatively.

CRF is a clinical syndrome presenting as metabolites retention, disturbances in water-electrolyte homeostasis and acid-base metabolism, and dysfunction of various organ systems in the body. It is a systemic problem involving many aspects of the patient. The complications of CRF, including DM, hypertension, and anemia, are important causes of vitreoretinopathy [4]. Additionally, the long-term administration of heparin anticoagulant drugs during hemodialysis also increases the risk of vitreous hemorrhage [7]. In more advanced cases, the eyes develop dense vitreous hemorrhage and tractional retinal detachment.

The current study suggests that by systemically considering the general and ophthalmic conditions, reducing intraoperative and postoperative incidence of systemic and ophthalmic complications, and decreasing the intraoperative and postoperative hemorrhage, ophthalmologists could perform surgeries to improve the visual function of the CRF patients with the support of a competitive medical team. Vitrectomy is an effective approach to treat severe vitreoretinopathy [8]. Prudent analysis of surgical indications, appropriate surgical techniques and timing, are critical for postoperative recovery of visual function. Patients with CRF are often combined with refractory hypertension, heart failure, and electrolyte disturbance, which often delay their ophthalmic surgeries. It is not prudent to perform vitrectomy without considering the comorbid conditions. However, overemphasizing the risks of surgery or even deciding against surgery, could increase the patient’s risk of becoming permanently blind. In this series of patients, 13 out of 16 were younger than 60. It is important to tackle their ocular pathologies and improve their visual function, which could improve their independence of daily activities and increase the quality of life. Previous study also showed that patients with diabetic nephropathy who underwent dialysis could safely undergo vitrectomy [9]. Therefore, with careful management of the systemic conditions, ophthalmologists could perform vitrectomy after proactively stabilizing the systemic conditions [10].

CRF Patients often have multiple abnormal indexes in the body. Recognizing the possible risks of synergetic effects of various abnormal indexes under the surgical stress state is pivotal to perioperative management of patients with CRF. Before the operation, a comprehensive assessment of general conditions and correction of abnormal indexes can reduce the possible risk of damaging heart, brain, and kidney function during the perioperative period.

Patients with renal dysfunction typically have unfavorable systemic conditions., Therefore, the surgery duration should be shortened to ensure the safety of patients. As for patients with severe vitreoretinopathy, they should be first treated with an intravitreal injection of anti-VEGF drugs, and then treated with vitrectomy, so that the surgery duration can be effectively shortened. The anti-VEGF injection 3 to 7 days before the operation can promote recession of neovascularization and decrease the rate of intraoperative hemorrhage. This in turn will improve the visibility during the surgery, reduce the likelihood of iatrogenic retinal hole formation during membrane removal, and prevent unnecessary repetitive use of intraocular instruments [15]. The aforementioned factors reduce the change of postoperative complications [16‐19]. Studies have shown that intraocular injection of anti-VEGF drugs will lead to recession of neovascularization. However, it may exacerbate the ischemia. Thus, it is not suitable for patients with severe ischemia. In addition, proliferative membranes without neovascularization would contract, which may exacerbate retinal detachment and result in traction-induced retinal breaks [20, 21]. Therefore, we performed intravitreal injection of anti-VEGF drugs on seven patients with severe vitreoretinopathy and conducted vitreoretinal surgery on the third day after injection, with no severe ischemia or hemorrhagic change during the surgery. All of them demonstrated a good therapeutic effect.