Biomechanical Considerations of Patching Material for Posterior Scleral Reinforcement Surgery.

Purpose: To characterize biomechanical properties of genipin-crosslinked human dura mater as reinforcing material for posterior scleral reinforcement (PSR) and to compare it with crosslinked human sclera. Methods: Donor dura mater and sclera were crosslinked in the same optimized genipin solution. Resistance to enzyme degradation for both materials were investigated by exposing the materials to accelerated enzyme degrading. Elastic modulus and tensile strength were measured by biomechanics testing equipment. Crosslinked human dura mater was used as reinforcing patch in PSR on 57 adult pathologic myopic eyes. The patients were followed up for an average 3 years. The main outcome was eye globe axial length change and safety profile of the reinforcing material. Results: Crosslinked dura mater demonstrated similar percentage weight loss to crosslinked sclera when exposed to enzymatic solution. Dura mater has higher density than sclera. The retaining elastic modulus after enzyme exposure was 72.02 MPa for crosslinked dura mater while 53.88 MPa for crosslinked sclera, 34% greater for crosslinked dura mater, P = 0.0186). At the end of 3 years follow-up, the mean globe axis of the surgery eyes was reduced by 1.29 mm (from 30.81 to 29.51 mm, P < 0.0001, paired t-test). Visual acuity (BCVA logMar) improved by 0.10 logMar unit which is an improvement of five letters (P = 0.0184, paired t-test). No material specific complication was noted. Conclusion: Crosslinked human dura mater may be superior to crosslinked human sclera as reinforcing material for PSR to manage progression of high myopia. This material was well tolerated on human eye.

Reduction in rectal doses of pelvic radiotherapy with excessive rectal gas extraction: a single-institution case report.

During radiotherapy for pelvic tumors, there might be insufficient radiation doses delivered that result from concerns of immediately adjacent critical organs, most notebly the rectum. Several measures have been proposed to reduce the rectal doses, such as use of a radioprotective spacer to shift the rectum away from the lesion or an endorectal balloon to reduce the internal target volume (ITV). The removal of rectal gas is supposed to achieve the similar effect by reducing the rectal volume and ITV. This is because the distance of the rectum to lesions can be increased with decreasing rectal volumes, which also makes it easy for physicists to avoid the rectum during field design. Besides, a reduced ITV can be obtained due to stability in rectal volume, as with use of an endorectal balloon. The procedure is most suitable for patients receiving stereotactic body radiotherapy (SBRT) and high dose rate brachytherapy (HDR-BR) because of limited treatment sessions. In this study, we showed that the rectal dose decreased significantly with rectal gas extraction, as manifested by dose parameters of D2 cm3 and D0.1 cm3 (the doses delivered to the most exposed 2 cm, 3 and 0.1 cm3 of the rectum, respectively). This technique is especially benefitable for candidates with excessive rectal gas fillings.

POSTERIOR SCLERAL CONTRACTION TO TREAT RECURRENT OR PERSISTENT MACULAR DETACHMENT AFTER PREVIOUS VITRECTOMY IN HIGHLY MYOPIC EYES.

PURPOSE: To determine the efficacy of posterior scleral contraction (PSC) to treat recurrent or persistent macular detachment after previous vitrectomy in highly myopic eyes. METHODS: We reviewed the medical records of patients with high myopia and recurrent or persistent macular detachment after previous vitrectomy treated with PSC at our hospital between April 2013 and March 2017. Fourteen eyes (14 patients; mean age, 58.93 ± 11.08 years) were included. Sclera cross-linked with genipin was used for PSC. The desired axial length decrease was 0.1-fold. The reattachment rate, best-corrected visual acuity, and axial length changes were evaluated. RESULTS: The macular reattachment rate was 100%. In seven eyes with a silicone oil tamponade, the oil was successfully removed 2 weeks to 4 months after surgery. The best-corrected visual acuity improved significantly postoperatively (Snellen acuity improved from 20/1,000-20/400) (1.75 ± 0.90 vs. 1.34 ± 0.58 logarithm of the minimal angle of resolution; P < 0.05). Eight eyes (57.14%) improved; six eyes (43.86%) remained stable. The axial length decreased significantly postoperatively (31.32 ± 3.04 vs. 29.08 ± 3.05 mm; P < 0.05). CONCLUSION: Posterior scleral contraction is safe and effective for recurrent and persistent macular detachment after previous vitrectomy in highly myopic eyes. The silicone oil is removed after PSC, and vision can be preserved in these refractory cases.

Genipin-Crosslinked Donor Sclera for Posterior Scleral Contraction/Reinforcement to Fight Progressive Myopia.

Purpose: Myopia has become a global public health problem, particularly in East Asia where myopic retinopathy has become one of the leading causes of blindness and visual impairment in the elderly population. The purpose of this study was to evaluate the efficacy of posterior scleral contraction/reinforcement (PSCR) surgery on controlling the progressive elongation of axial length of highly myopic eyes in young patients. Methods: This is a prospective self-controlled interventional case series. Forty young patients (<18-years old) with progressive high myopia received PSCR with a genipin-crosslinked donor scleral strip for one eye and the fellow eye served as concurrent control without surgery. The main outcome measurement was the change of axial length over 2 to 3 years of follow-up. Results: Immediately after the surgery, axial length was shortened and subsequently increased by 0.32 mm over the follow-up period. In contrast, axial length of the fellow eyes increased by 0.82 mm over the same period (P < 0.001, paired t-test). PSCR delayed axial elongation in eyes with or without staphyloma. No significant change of visual acuity, cornea refractive power, or retina thickness was noted between the surgery and fellow eyes. None of the patients lost visual acuity compared with the baseline. The procedure was well tolerated with only temporary corneal refractive axis shifts that recovered by the 6-month postsurgical visit. Conclusions: PSCR with genipin-crosslinked sclera is safe and effective to restrain eye globe elongation in young patients within a 2- to 3-year follow-up period.

Posterior scleral reinforcement using genipin-cross-linked sclera for macular hole retinal detachment in highly myopic eyes.

BACKGROUND/AIMS: To investigate the surgical outcomes of posterior scleral reinforcement (PSR) using genipin-cross-linked sclera to treat macular hole retinal detachment (MHRD) in highly myopic eyes. METHODS: Nineteen patients with high myopia (19 eyes) with MHRD were treated sequentially with genipin-cross-linked PSR and were followed at least for 1 year after the surgery. The best corrected visual acuity (BCVA), axial length (AL), optical coherence tomography (OCT) outcomes and the complications were evaluated. RESULTS: Macular hole was closed in 73.7% of the eyes, foveal reattachment rate was 100%. The mean logMAR BCVA improved from 1.27±0.55 preoperatively to 0.88±0.55 postoperatively. The preoperative AL (29.88±1.97 mm) was decreased (27.73±1.84 mm) after the operation (p<0.001). CONCLUSIONS: For at least a 1-year period of follow-up, PSR with genipin-cross-linked sclera should be considered as a preferred surgical approach to treat MHRD in highly myopic eyes, especially when foveal retinoschisis is also documented.

The efficacy of posterior scleral contraction in controlling high myopia in young people.

OBJECTIVE: To investigate the clinical effectiveness and safety of posterior scleral contraction (PSC) surgery in controlling high myopia in young people. METHODS: Twenty patients with high myopia (30 eyes) were treated with PSC. The average age for the patients was 11.45 ± 5.17 years old (range 3-22). A genipin cross-linked sclera was implanted to the posterior sclera in PSC surgery. Axial length and myopia progression rates were measured at least two years before and after PSC surgery. RESULTS: Prior to surgery, the mean AL progression was 0.73 ± 0.33 mm, compared to -0.08 ± 0.31 mm (P=0.00) post-surgery; the degree of myopia increased was -1.40 ± 0.95 D, compared to 0.18 ± 1.10 D post-surgery (P=0.00). The best corrected visual acuity (BCVA, in LogMAR) improved from 0.21 ± 0.16 preoperatively to 0.13 ± 0.13 two years after PSC (P=0.014). CONCLUSIONS: PSC can restrict AL extension and safely control high myopia progression in young people.

Lower Beclin 1 downregulates HER2 expression to enhance tamoxifen sensitivity and predicts a favorable outcome for ER positive breast cancer.

Tamoxifen(TAM) is one of the most effective endocrine treatment for estrogen receptor(ER)-positive breast cancer, however drug resistance greatly limits benefit of it. Our purpose is to uncover the role of Beclin 1 in tamoxifen resistance and prognosis of ER positive breast cancer. We established a tamoxifen resistant ER-positive breast cancer cell subline MCF-7R presenting with higher Beclin 1 and human epidermal growth factor receptor 2(HER2) levels than MCF-7. Silencing Beclin 1 decreased levels of HER2 and significantly promoted TAM sensitivity of MCF-7 and MCF-7R in vitro. Overexpression of HER2 could reverse TAM sensitivity, which was formerly increased in Beclin 1 downregulated cell. Beclin 1 level was not only positively correlated with level of HER2 but also negatively correlated with overall survival of ER-positive breast cancer patients. Using bioinformatic methods, Beclin 1 mRNA was found to be negatively correlated with overall survival in breast cancer patients receiving TAM treatment. This study indicated for the first time that lower HER2 expression by Beclin 1 downregulation contributes to alteration of tamoxifen sensitivity and low Beclin 1 predicts favorable outcome in ER-positive breast cancer.

Comparison between toric and spherical phakic intraocular lenses combined with astigmatic keratotomy for high myopic astigmatism.

BACKGROUND: To compare the outcomes of a toric phakic intraocular lens (PIOL) and a spherical PIOL combined with astigmatic keratotomy (AK) for the correction of high myopic astigmatism. METHODS: This study enrolled patients with high myopic astigmatism, including 30 eyes (22 patients) that received a toric PIOL implantation (TICL group), and 32 eyes (24 patients) that received combined AK and a spherical PIOL implantation (AK+ ICL group). The outcomes were compared between the two groups before surgery, and at the following time points after surgery: 1 week, 1, 3, 6 months, and 1, 2 years. RESULTS: Preoperatively, the mean manifest spherical equivalent (SE) was -14.14 ± 2.12 D in the TICL group and -14.83 ± 2.79 D in the AK + ICL group (P = 0.28), and the mean manifest refractive cylinder, -2.87 ± 1.09 D and -2.58 ± 0.85 D, respectively (P = 0.28). Two years postoperatively, the mean safety index was 1.53 ± 0.55 in the TICL group and 1.60 ± 0.70 in the AK + ICL group (P = 1.00), and the mean efficacy index, 1.18 ± 0.45 and 1.38 ± 0.52, respectively (P = 0.86). The mean manifest refractive cylinder correction was 1.94 ± 1.07 D in the TICL group and 1.39 ± 0.71 D in the AK + ICL group (P = 0.02). The mean changes in SE and refractive cylinder from 1 week to 2 years were less than 0.50 D in both groups. CONCLUSIONS: Both TICL implantation and AK + ICL implantation are a good alternative for correction of astigmatism in addition to high myopia. TICL implantation has better predictability in correction of high myopic astigmatism. TRIAL REGISTRATION: NCT03202485.

The efficacy and safety of posterior scleral reinforcement using genipin cross-linked sclera for macular detachment and retinoschisis in highly myopic eyes.

BACKGROUND/AIMS: To evaluate the efficacy and safety of posterior scleral reinforcement (PSR) using genipin cross-linked sclera as the material to treat macular detachment and retinoschisis, both without macular hole, in highly myopic eyes. METHODS: Twenty-one patients with highly myopic eyes (24 eyes) with macular detachment and retinoschisis were treated sequentially with genipin cross-linked PSR and were followed for at least 1 year after surgery. The best-corrected visual acuity (BCVA), spherical equivalent (SE) power, axial length (AL), optical coherence tomography, and the complications were evaluated. RESULTS: The mean SE decreased from -13.81±4.67 D preoperatively to -9.64±4.86 D postoperatively, while the improvement in the logMAR BCVA values was from 1.24±0.57 before surgery to 1.03±0.57 after surgery. The preoperative AL (29.73±2.31 mm) was decreased (28.08±2.08 mm) after the operation. The retina in 21 eyes (87.5%) was successful reattached and the macular detachment was significantly decreased in two eyes; a macular hole occurred in one eye. CONCLUSIONS: For at least a 1 year period of follow-up, PSR with genipin cross-linked sclera was safe and effective to treat macular detachment and retinoschisis in high myopia when a macular hole was not present. The reinforcement effect tended to be stabilised and maintained for 6 months after treatment.

Preliminary clinical investigation of cataract surgery with a noncontact femtosecond laser system.

BACKGROUND AND OBJECTIVE: Femtosecond laser-assisted cataract surgery (FLACS) is rapidly gaining popularity due to the improved consistency and predictability for capsulorhexis. This study aimed to investigate the preliminary clinical outcomes of FLACS with a noncontact femtosecond laser system. PATIENTS AND METHODS: This prospective study enrolled 25 eyes in the trial group underwent FLACS (LLS-fs 3D, LENSAR, USA), and 29 eyes in the control group underwent conventional cataract surgery (Stellaris, Bausch & Lomb, USA). The phacoemulsification time, energy, and complications during operation were recorded. Postoperative refraction at 1 day, 1 week, 1 and 3 months, the capsulorhexis size and corneal endothelial density at 1 and 3 months were also measured. RESULTS: Compared to the control group, reduction in phacoemulsification time was 51.5% (P = 0.02), and in overall energy, 65.1% (P = 0.02) in the trial group. In the trial group and the control group, total time of cataract procedure was 10.04 ± 1.37 minutes, 10.52 ± 1.92 minutes, respectively (P = 0.31); the absolute difference between attempted and achieved capsulorhexis diameter at 1 month was 192.9 ± 212.0 µm, 626.9 ± 656.6 µm, respectively (P = 0.04), and at 3 months, 256.6 ± 181.9 µm, 572.1 ± 337.0 µm, respectively (P= 0.03); the absolute difference between attempted and achieved spherical equivalent at 3 months was 0.16 ± 0.16 D, 0.74 ± 0.65 D, respectively (P < 0.01); mean corneal endothelial cell loss at 1 month was 15.6% and 14.2%, respectively (P = 0.77), and at 3 months, 2.9%, 4.2%, respectively (P = 0.50). CONCLUSIONS: With the noncontact femtosecond laser system, FLACS can significantly improve the accuracy and repeatability of capsulorhexis, reduce the phacoemulsification time and overall energy, and enhance the predictability and stability of postoperative refraction.

Posterior scleral reinforcement on progressive high myopic young patients.

PURPOSE: To evaluate the effect of posterior scleral reinforcement in controlling high myopic axial progression in young patients. METHODS: Only one eye of each patient had posterior scleral reinforcement surgery. Before surgery and at each postoperative follow-up, the best corrected visual acuity, intraocular pressure, refractive errors, indirect ophthalmoscopy, B-type ultrasonography, and IOLMASTER reflected light biometry were performed on both eyes. The changes of axial length and the changes of refractive errors from the baseline were compared between the surgery eyes and the contralateral eyes. RESULTS: Thirty patients had a mean age of 7.5 years and a mean spherical equivalent of -9.72 diopters. The mean elongation of axial length was significantly less in the surgery eye group than that in the contralateral eye group (0.75 mm vs. 0.94 mm, p < 0.0001, paired t test) after a mean follow-up of 895 days. The surgical effect was mild but maintained during the follow-up. The eyes with staphyloma gained less surgical effect when compared with the eyes without staphyloma (p = 0.0036). There was also a notable nonstatistically significant trend for younger patients to gain a larger surgical effect (p = 0.0986). CONCLUSIONS: Posterior scleral reinforcement surgery was found effective in slowing down high myopic axial progression in young patients within the study period, but the size of the effect was small. The surgical procedure is well tolerated without vision-threatening complications.