Intravitreal gas injection for early persistent macular hole after primary pars plana vitrectomy.

PURPOSE: To report the clinical presentations and outcome of early intravitreal injection (IVI) of octafluoropropane (C3F8) for persistent macular holes (MH) after primary pars plana vitrectomy with the internal limiting membrane (ILM) peeling technique. METHODS: Nineteen eyes of 18 patients with persistent MH after vitrectomy underwent intravitreal injection of C3F8 between 11 and 21 days after the initial surgery (intravitreal gas injection group). Another nine eyes with a persistent MH without additional IVI C3F8 were included (non-intravitreal gas injection group). Best-corrected visual acuity (BCVA), optical coherence tomography (OCT) features including size and configuration of MH, and time duration between the 2 surgeries were compared between the MH closure and open groups. The closure rate of persistent MHs was compared between the intravitreal gas injection group and non-intravitreal gas injection group. RESULTS: Twelve of 19 eyes (63%) achieved MH closure after 1 to 3 times IVI C3F8. The final BCVA after vitrectomy and IVI gas was significantly better in the MH closure group (P = .005). Nine of 12 patients (75%) in the MH closure group had a visual acuity improvement of more than 2 lines. Original MHs with smaller minimal diameter, higher macular hole index (MHI) and higher tractional hole index (THI); and persistent MHs with smaller minimal diameter, higher THI, and lower diameter hole index (DHI) showed higher MH closure rate. None of the persistent MHs closed in the non-intravitreal gas injection group (0/9 eyes). CONCLUSION: Early intravitreal injection of C3F8 can be a cost-effective first-line treatment for early persistent MHs after primary surgery, especially in eyes with favorable OCT features.

Inverted internal limiting membrane flap technique in eyes with large idiopathic full-thickness macular hole: long-term functional and morphological outcomes.

PURPOSE: To investigate morphological and functional outcomes of the inverted internal limiting membrane (I-ILM) flap technique in large (≥ 400 µm) idiopathic full-thickness macular holes (FTMH) over a follow-up period of 12 months. METHODS: In this retrospective study, 55 eyes of 54 consecutive patients were enrolled. Best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT, Heidelberg, Spectralis) were performed preoperatively as well as 1, 3, 6, 9, and 12 months postoperatively. Special focus was put on the reintegration of outer retinal layers and the different ILM flap appearances. RESULTS: FTMH closure rate was 100% (55/55). BCVA significantly improved over the follow-up period of 12 months from 0.98 ± 0.38 LogMAR preoperatively to 0.42 ± 0.33 LogMAR at 12 months postoperatively (p < 0.001). There was no significant correlation between the three different ILM flap appearances and BCVA. Better preoperative BCVA, complete restoration of the external limiting membrane (ELM), higher macular hole index (MHI), and smaller MH base diameter were associated with higher improvement of BCVA. CONCLUSION: Our study highlights the favorable morphological and functional outcomes of the I-ILM flap technique in the short as well as in the long term. While complete ELM restoration revealed to be an important factor for improvement in BCVA, the different postoperative ILM flap appearances seem not to be related to BCVA.

Optical Coherence Tomography based indices in predicting functional outcome of macular hole surgery: A retrospective chart review.

OBJECTIVES: The objective of this study was to assess the utility of novel macular hole indices of Optical Coherence Tomography (OCT) and predicting the functional outcome of surgery. METHODS: This was a retrospective chart review of 28 eyes who underwent surgery for idiopathic Full Thickness Macular Hole (FTMH) at The Aga Khan University Hospital (AKUH), Karachi from January 2016 to March 2020. Data of preoperative OCTs were recovered from data server of OCT machine. Measurements of the pre-operative OCTs were calculated using caliper function of OCT software by two independent technicians. Parameters included Macular Hole Index (MHI), Traction Hole Index (THI), Hole Form Factor (HFF) and Diameter Hole Index (DHI) were recorded. Receiver operating characteristic (ROC) curve was used to evaluate the performance of DHI, THI, HFF and MHI for improved BCVA after surgery, by looking at sensitivity, specificity and area under curve (AUC). P-value of <0.05 was considered significant. RESULTS: Out of 30 eyes, final data analysis was done for 28 eyes. Mean age was 61.5 ± 6.2 years. Mean pre-operative and 6 months post-operative LogMAR best corrected visual acuity (BCVA) was 0.84 ± 0.23 and 0.32 ± 0.30 (p-value <0.001). Area under the curve with 95% confidence interval estimated for DHI, THI, HFF, and MHI was [0.750 (0.559 to 0.889)], [0.827 (0.637 to 0.943)], [0.846 (0.660 to 0.954)], [0.827 (0.637 to 0.943)]. Cut off values for predicting good functional outcome (post-op BCVA equal or better that 0.4) for DHI, THI, HFF and MHI were 0.454, 1.086, 0.856 and 0.501 respectively. All ROC value of less than 0.5 were considered unlikely to predict functional outcomes with macular hole indices. CONCLUSION: Novel macular hole indices can be used as a tool to predict the functional outcomes of macular hole surgery. Larger studies may be required to assess their wider effectiveness.

Pre-operative predicting factor in visual outcome after macular hole surgery.

OBJECTIVE: To determine the effectiveness of macular hole index (MHI) as a predicting factor of visual outcome after full thickness macular hole surgery. METHODS: This quasi-experimental study was conducted at LRBT Free Base Eye Hospital, Karachi from January 2018 to March 2019. Total 45 eyes of 45 patients with full thickness macular hole (FTMH) underwent preoperative Best Corrected Visual Acuity (BCVA) assessment with logMar chart and Optical Coherence Tomography (OCT) scanning, with measurement of base diameter and macular hole height. Values were calculated for the macular hole index (MHI), which was taken as the predictive factor. All patients had undergone 25+G trans-conjunctival three ports pars plana vitrectomy, internal limiting membrane peeling, and endo-tamponade of C3F8(14%). The final visual outcome of all the patients was noted. RESULTS: Forty-five patients were included for the study, out of which 10 (22.2%) were male and 35 (77.7%) were female. Age ranged from 45-70 years (mean age 57.20±6.47 years). The mean pre-operative visual acuity was 2.46±1.15 logMar and was 3.88±2.00 logMar, post-operatively. Moreover, 27(60.0%) out of 45 patients achieved BCVA (gain of 2 lines of the logMar chart). The average macular hole index was 1.55±0.50 and out of 45, 25 patients had MHI ≥0.5. It was found that patients with macular hole index ≥0.50 showed clinically significant improvement in BCVA in comparison to those who have macular hole index <0.50. CONCLUSION: Macular hole index can be used to predict functional success in macular hole surgery.

Bio-efficacy and physical integrity of piperonylbutoxide coated combination net (PermaNet® 3.0) against pyrethroid resistant population of Anopheles gambiae s.l. and Culex quinquefasciatus mosquitoes in Ethiopia.

BACKGROUND: PermaNet® 3.0 is a deltamethrin-treated combination long-lasting insecticidal net with the addition of synergist piperonylbutoxide (PBO) on its roof section. It is designed to overcome the challenge posed by pyrethroid resistant vector populations against mainstream long-lasting insecticidal nets impregnated with pyrethroids only. The objective of this study was to determine insecticide resistance status of Anopheline and Culicine mosquitoes, to evaluate the bio-efficacy of PermaNet® 3.0 nets and to assess household factors affecting the physical integrity of PermaNet® 3.0 after 3 years of use. METHODS: Insecticide susceptibility test was conducted using the WHO tube test. Bio-activity of PermaNet® 3.0 samples was evaluated using the WHO cone bioassay. Cross-sectional survey was conducted on 150 randomly selected households from two districts to determine household factors affecting net utilization. One hundred fifty PermaNet® 3.0 nets were randomly collected from the community with replacement after 3 years of deployment and physical integrity of each net was assessed. RESULTS: Both Anopheles gambiae sensu lato and Culex quinquefasciatus developed resistance against permethrin and deltamethrin. However, following pre-exposure to synergist PBO the susceptibility of mosquito population increased to both permethrin (from 39% without to 92% with PBO against An. gambiae and from 28% without to 94% with PBO against Culex quinquefasciatus) and deltamethrin (from 52% without to 99% with PBO against An. gambiae and from 43% without to 98% with PBO against Culex quinquefasciatus). Eighty percent (80%) mortality was recorded in wild population of An. gambiae s.l. exposed to unused PermaNet® 3.0, but its bioactivity subsequently declined as washing frequency increased from 0 to 20. The PBO coated roof section of unused PermaNet® 3.0 resulted in higher mosquito mortality (100%) compared to the side panels without PBO (85%). House structure, cooking and washing habits, and damage due to household pests were cited as determinants associated with bed net deterioration. Bed net proportionate hole index (pHI) was ranged from 0 to 6064. Of the 150 PermaNet® 3.0 nets assessed 80, 29 and 41 were considered as 'good', 'acceptable' and 'too torn', respectively. CONCLUSIONS: The bio-efficacy evaluation of PermaNet® 3.0 from Jimma area, southwestern Ethiopia showed moderate efficacy against pyrethroid resistant population of An. gambiae and Culex quinquefasciatus. Thus, NMCPs in parallel to deployment of LLINs, should implement timely insecticide resistance management and integrated vector management strategies to slowdown the evolution and further spread of insecticide resistance. Household factors such as, housing conditions, open flame fire used for cooking and rodent attack were identified as factors contributing to the observed reduced bed net physical integrity in the study area. Universal coverage of bed nets should be accompanied with community awareness creation and training on net utilization and handling.

Assessing bed net damage: comparisons of three measurement methods for estimating the size, shape, and distribution of holes on bed nets.

BACKGROUND: Measuring the physical condition of long-lasting insecticidal nets (LLINs) under field conditions is of great importance for malaria control programmes to guide decisions on how frequently to replace LLINs. Current guidelines by the World Health Organization Pesticide Evaluation Scheme (WHOPES) propose a proportionate hole index (pHI) for assessing LLIN condition by counting the number of holes the size of a thumb, fist, head, and larger than a head. However, this method does not account for irregular hole shapes or exact hole sizes which could result in inaccurate decisions about when to replace LLINs. METHODS: LLINs were collected during a 2013 health facility-based malaria case control study in Machinga District, Malawi. To evaluate the accuracy of the pHI, the physical condition of 277 LLINs was estimated by the WHOPES method and then compared with two more thorough measurement methods: image analysis of digital photographs of each LLIN side; and for 10 nets, ruler measurements of the length, width, and location of each hole. Total hole counts and areas per net were estimated by each method, and detailed results of hole shapes and composite pictures of hole locations were generated using image analysis. RESULTS: The WHOPES method and image analysis resulted in similar estimates of total hole counts, each with a median of 10 (inter-quartile range (IQR) 4-24 and 4-23, respectively; p = 0.004); however, estimated hole areas were significantly larger using the WHOPES method (median 162 cm2, IQR 28-793) than image analysis (median 13 cm2, IQR 3-101; p < 0.0001). The WHOPES method classified fewer LLINs in 'good condition' compared to image analysis (42% vs 74%). The ruler method detected significantly more holes than image analysis did (p = 0.002) in 10 LLINs; however, total hole area was not significantly different (p = 0.16). Most holes were not circular but roughly 2-5 times longer in one direction. The lower quarter of LLIN sides was found to have the most holes. CONCLUSIONS: The WHOPES method overestimated total hole area, likely because holes are elongated rather than circular, suggesting further adjustments to the pHI formula may be warranted when considering LLIN replacement strategies.

Anatomical and Functional Outcomes in Eyes with Idiopathic Macular Holes that Underwent Surgery Using the Inverted Internal Limiting Membrane (ILM) Flap Technique Versus the Conventional ILM Peeling Technique.

INTRODUCTION: To evaluate the anatomical and functional outcomes of the inverted internal limiting membrane (ILM) flap technique (IFT) in macular holes (MHs), especially in MHs with a macular hole index (MHI) < 0.5. METHODS: This was a retrospective comparative study. Patients with idiopathic MHs who underwent either the IFT or conventional ILM peeling (CP) were investigated. The main outcomes included the MH closure rate, best corrected visual acuity (BCVA), and recovery rates of the external limiting membrane (ELM) and ellipsoid zone (EZ) at 1, 3, and 6 months postoperatively. RESULTS: Forty-eight eyes of 48 patients who underwent the IFT (n = 29, Group A) or CP (n = 19, Group B) were included. The mean minimal diameter was 522.00 ± 208.08 µm. The closure rate was 100.0% in Group A and 94.7% in Group B (P = 0.396). The mean BCVA and EZ and ELM recovery rates improved significantly in both groups postoperatively. No significant differences in BCVA or the EZ or ELM recovery rates were found between the two groups. Of the 39 eyes whose MHI was < 0.5, 25 underwent the IFT, and 14 underwent CP. Comparing the results of the closure rate, BCVA and recovery rates of the EZ and ELM between groups were similar to those in 48 eyes. CONCLUSION: Both the IFT and CP can achieve a high closure rate, with no significant difference in ordinary idiopathic MHs. The IFT does not seem to achieve better anatomical and functional outcomes than CP. The IFT should be used conservatively in ordinary non-refractory MH surgery.

The durability of long-lasting insecticidal nets distributed to the households between 2009 and 2013 in Nepal.

BACKGROUND: Understanding and improving the durability of long-lasting insecticidal nets (LLINs) in the field are critical for planning future implementation strategies including behavioral change for care and maintenance. LLIN distribution at high coverage is considered to be one of the adjunctive transmission reduction strategies in Nepal's Malaria Strategic Plan 2014-2025. The main objective of this study was to assess the durability through assessment of community usage, physical integrity, residual bio-efficacy, and chemical retention in LLINs: Interceptor®, Yorkool®, and PermaNet ®2.0 which were used in Nepal during 2009 through 2013. METHODS: Assessments were conducted on random samples (n = 440) of LLINs from the eleven districts representing four ecological zones: Terai plain region (Kailali and Kanchanpur districts), outer Terai fluvial ecosystem (Surkhet, Dang, and Rupandhei districts), inner Terai forest ecosystem (Mahhothari, Dhanusa, and Illam districts), and Hills and river valley (Kavrepalanchock and Sindhupalchok districts). For each LLIN, fabric integrity in terms of proportionate hole index (pHI) and residual bio-efficacy were assessed. However, for chemical retention, a representative sample of 44 nets (15 Yorkool®, 10 Permanet®2.0, and 19 Interceptor®) was evaluated. Data were analyzed using descriptive statistics stratified by LLINs brand, districts, and duration of exposure. RESULTS: On average, duration of use of LLINs was shortest for the Yorkool® samples, followed by PermaNet® 2.0 and Interceptor® with median ages of 8.9 (IQR = 0.4), 23.8 (IQR = 3.2), and 50.1 (IQR = 3.2) months, respectively. Over 80% of field distributed Yorkool® and PermaNet® 2.0 nets were in good condition (pHI< 25) compared to Interceptor® (66%). Bio-efficacy analysis showed that average mortality rates of Interceptor and Yorkool were below World Health Organization (WHO) optimal effectiveness of ≥ 80% compared to 2-year-old PermaNet 2.0 which attained 80%. Chemical retention analysis was consistent with bio-efficacy results. CONCLUSION: This study shows that distribution of LLINs is effective for malaria control; however, serviceable life of LLINs should be considered in terms of waning residual bio-efficacy that warrants replacement. As an adjunctive malaria control tool, National Malaria Control Program of Nepal can benefit by renewing the distribution of LLINs in an appropriate time frame in addition to utilizing durable and effective LLINs.

Preoperative prognostic factors for macular hole surgery: Which is better?

AIM: This study aims to evaluate the prognostic factors of different optical coherence tomography (OCT) parameters as well as the tamponade used in surgery, on postoperative anatomical and functional success. METHODS: Twenty-nine eyes of 27 patients were included in this study. A three-port 23-gauge pars plana vitrectomy was performed on all eyes with peeling of the internal limiting membrane by visualization with brilliant blue dye by the same surgeon (E.U). Apical diameter (AD), base diameter (BD), and height (H) were manually measured by the same retina specialist (E.U) with using the software on OCT machine. Macular hole index (MHI), tractional hole index, diameter hole index, and macular hole volume (MHV) were calculated. The correlation between predictive factors and postoperative best corrected visual acuity (BCVA) was evaluated. RESULTS: A statistically significant positive correlation was observed between preoperative BCVA, AD, BD, MHV, and postoperative BCVA scores. A statistically significant negative correlation was observed between preoperative MHI and postoperative BCVA scores (r = -0.676, P = 0.001). The strongest positive correlation was between BD and postoperative BCVA (logMAR) (r = 0.732, P = 0.001). The visual improvement was statistically better in patients treated with C3F8 than SF6. CONCLUSION: BD and MHV could be used as a strong predictive OCT parameters of postoperative functional success.

Value of spectral domain-optical coherence tomography parameters on evaluating visual acuity improvement after internal limiting membrane peeling of macular hole / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To analyze the application value of spectral domain-optical coherence tomography(SD-OCT)parameters on evaluating visual acuity improvement after internal limiting membrane peeling of macular hole.METHODS: The retrospective analysis was performed on the clinical data of 82 patients(82 eyes)with idiopathic macular hole(IMH)who underwent vitrectomy + internal limiting membrane peeling + long-acting gas tamponade in the hospital between May 2019 and February 2021. The correlation between IMH closure and SD-OCT parameters at 3mo after surgery was analyzed, and the risk factors for poor postoperative visual acuity improvement were evaluated.RESULTS: Spearman rank correlation coefficient analysis showed that IMH closure at 3mo after operation was positively correlated with preoperative external limiting membrane(ELM)defect diameter(rs=0.308, P&#x003C;0.05), and it was negatively correlated with preoperative macular hole index(MHI; rs=-0.266, P&#x003C;0.05). Logistic regression analysis revealed that preoperative MHI≥0.5 was a protective factor affecting poor postoperative visual acuity improvement(OR=0.691, P&#x003C;0.05).CONCLUSION: SD-OCT can predict the surgical efficacy by detecting the preoperative MHI and ELM defect diameter, and it is beneficial to judging the improvement of visual function.