A new instrument for drainage or injection of fluid within subretinal space

Steady-Hand Eye Robot 3.0: Optimization and Benchtop Evaluation for Subretinal Injection

Subretinal injection methods and other procedures for treating retinal conditions and diseases (many considered incurable) have been limited in scope due to limited human motor control. This study demonstrates the next generation, cooperatively controlled Steady-Hand Eye Robot (SHER 3.0), a precise and intuitive-to-use robotic platform achieving clinical standards for targeting accuracy and resolution for subretinal injections. The system design and basic kinematics are reported and a deflection model for the incorporated delta stage and validation experiments are presented. This model optimizes the delta stage parameters, maximizing the global conditioning index and minimizing torsional compliance. Five tests measuring accuracy, repeatability, and deflection show the optimized stage design achieves a tip accuracy of < 30 μm, tip repeatability of 9.3 μm and 0.02°, and deflections between 20-350 μm/N. Future work will use updated control models to refine tip positioning outcomes and will be tested on in vivo animal models.

Advances in the treatment of rhegmatogenous retinal detachment

The pathogenesis of rhegmatogenous retinal detachment depends on three factors, namely, retinal rupture, vitreous liquefaction and traction causing the retina to separate from the pigment epithelium, among which retinal rupture is the most important. Retinopathy is caused by a gap between the neurosensory retina and the retinal pigment epithelium, which severely damages the visual function of the patient. Therefore, early clinical discovery, prevention and selection of an appropriate treatment are important. This article reviews progress in the treatment of retinal detachment.

Inferior sclerotomies without subretinal fluid drainage for exudative retinal detachment in diffuse retinal pigment epitheliopathy

PURPOSE

To evaluate the efficacy of inferior sutureless sclerotomies without subretinal fluid drainage for the treatment of bullous exudative retinal detachment secondary to diffuse retinal pigment epitheliopathy.

METHODS

A retrospective interventional case series of eyes treated with two inferior postequatorial full-thickness sclerotomies without subretinal fluid drainage. Patients were placed in an upright position 24 hours after surgery. Main outcomes were visual acuity and retinal reattachment rate.

RESULTS

Three eyes with recent diagnoses of diffuse retinal pigment epitheliopathy and bullous inferior retinal detachment were included in the study. In all cases, a very thick sclera was evident during surgery. The day after surgery the retina was completely attached in the three eyes. Preoperative visual acuity was light perception, 20/200, and counting fingers. After surgery, visual acuity improved to 20/200, 20/70, and 20/50, respectively. No intra- or postoperative complications occurred.

CONCLUSIONS

The performance of inferior sutureless sclerotomies without a draining procedure in cases of diffuse retinal pigment epitheliopathy with inferior bullous retinal detachment is a simple and effective technique. It achieves retinal reattachment the day after surgery, allowing laser photocoagulation of the leaking lesions disclosed in fluorescein angiography.

Modified external needle drainage of subretinal fluid in primary rhegmatogenous retinal detachment: a prospective, consecutive, interventional, single-surgeon study

PURPOSE

We describe surgical outcomes in a single-surgeon, consecutive series of patients who received scleral buckle placement for primary retinal detachment using a modified external needle drainage technique.

METHODS

Eighty-two eyes of 80 patients with primary retinal detachment underwent scleral buckle placement with modified external needle drainage. Preoperative, postoperative, and surgical data were collected. Regression analysis was used to evaluate the association between preoperative clinical data and number of surgeries.

RESULTS

The retinal detachment most commonly involved 41% to 50% of the retina. Seventy-six eyes (92.7%) were repaired after 1 surgical procedure, 98.8%, after 2 procedures, and 100%, after 3 procedures. No preoperative clinical variables were found to be significantly correlated with the number of surgeries performed. Vision improved an average of 0.3 logarithm of the minimal angle of resolution or 3 lines of vision (P < 0.001). One eye (1.2%) developed a localized subretinal hemorrhage at the drainage site that resolved spontaneously.

CONCLUSIONS

The modified external needle drainage technique used during scleral buckle placement appears to be safe and effective in patients with primary retinal detachment.

Surgical management of bilateral exudative retinal detachment associated with central serous chorioretinopathy

Purpose

To report a case of bilateral bullous exudative retinal detachment in central serous chorioretinopathy (CSC) which was attached by vitrectomy and internal drainage of the subretinal fluid.

Methods

A 47-year-old man affected by bilateral atypical CSC with a bullous retinal detachment with subretinal exudate. A fluorescein angiogram (FAG) showed multiple points of leakage and staining of subretinal fibrosis. A tentative diagnosis of Vogt-Koyanagi-Harada (VKH) syndrome was made and the patient was treated with systemic corticosteroids and immunosuppressive agents. However, the subretinal fluid was not absorbed. He was then treated with vitrectomy and internal drainage of subretinal fluid.

Results

The retina was attached successfully in both eyes. Visual acuity improved to 20/50 in his left eye but did not improve in the right eye due to subretinal fibrotic scarring and atropic changes on the macula.

Conclusions

Our case suggests that the surgical management of bullous exudative retinal detachment is safe and necessary.