A comprehensive investigation of toxicity and pollution potential of municipal solid waste landfill leachate

It is evident from the literature that research on the treatment of leachate generated from municipal solid waste (MSW) landfills has been a focus area of environmental management. However, the available information is discrete because most studies have reported only one or a couple of aspects of either closed or active MSW landfill leachate treatment. Hence, this investigation has focused on comprehensive attributes of both closed landfill leachate (CLL) and active landfill leachate (ALL), including generation, characterisation, and toxicity assessment to quantify and establish their pollution potential. The results indicated that CLL generation is higher (188.59 m³/d) than ALL (49.53 m³/d). The concentrations of principal physical, chemical, and biological constituents and concomitant leachate pollution index were higher in CLL (33.20) than in ALL (26.65). Furthermore, the germination indices of CLL (57.48) and ALL (79.14) and tail DNA damage of CLL (56.49%) and ALL (23.8%) ratified greater phytotoxicity and genotoxicity potential, respectively of CLL over ALL. The reasons for the variations in the generation, characteristics, and toxicity of CLL and ALL were discussed in detail. Evaluation of the commonly used landfill leachate treatment methods through the analytical hierarchy process confirmed that the activated sludge process and Fenton oxidation process are the most and least preferred treatment methods. The comprehensive investigation of CLL and ALL have established their pollution potential and the inevitable necessity for their treatment. The findings of this investigation will serve as a ready reference for researchers from academia and industry who work on the monitoring, treatment, and management of landfill leachate.

Radiative effects of atmospheric aerosols on the average channel capacity of free-space optical communication systems

Free-space optical (FSO) communication systems employ unguided light beams propagating through the atmosphere to carry a large volume of data. The reliability of such data transfer can be hampered by various atmospheric effects. Based on an analytical model of a differential phase-shift keying FSO system through exponentiated Weibull turbulence, we investigate the effectiveness of beam width optimization and improved beam alignment, along with aperture averaging on the average channel capacity. Our results show significant signal deterioration produced due to the aerosol-induced optical turbulence, which substantially shadows the performance gain achieved through beam width optimization. Strong aerosol-induced atmospheric heating and the consequent enhanced optical scintillations result in reduction of the channel capacity by as much as 50% of its value when these effects are not considered or negligible. FSO systems are more resilient to aerosol-induced optical turbulence when the normalized beam width is less, and the average channel capacity can be significantly improved by improved beam alignment. These variations are weakly dependent under poor transmitter-receiver alignment conditions. Furthermore, the receiver aperture has a strong control on the link performance. While FSO systems with higher magnitude of normalized beam width have improved performance under all aperture diameter conditions; for a given beam configuration, large aperture diameter ensures a significant improvement in the link performance due to reduction in effects of scintillations.

Enhanced optical pulse broadening in free-space optical links due to the radiative effects of atmospheric aerosols

Propagation through turbulent media produces complex amplitude fluctuations and temporal spreading of narrow optical pulses. Light-absorbing aerosols present in the atmospheric transmission path will perturb the refractive index structure parameter (Cn2) through atmospheric heating. The consequent enhancement in broadening and attenuation of ultrashort (femtosecond) optical pulses has been calculated by combining multi-satellite observations, radiosonde profiles and computational radiative transfer. It is shown that narrower optical pulses are more vulnerable to aerosol-induced impairments while broader pulses are more resilient, notwithstanding three to four orders of enhanced optical scintillation.

Epidemiological profiling of fatal road crashes in Puducherry, South Coastal India

Road crash fatalities form leading cause of deaths in India. Streamlining road crash data systems are essential for building robust prevention strategies. This study explores epidemiological profile of fatal road crashes in a south Indian urban setting. Between April and June 2019, secondary data on fatal road crashes in Puducherry district for 3-year period (2016, 2017, and 2018) were accessed from traffic police records and analyzed. Raw data accessed in descriptive format was converted to analyzable objective format by self-developed data extraction template. 154 fatal crashes happened in Puducherry during this period. Most victims were males (85.7%), in productive age group (41.5%), with higher rates in monsoon and winter seasons (35.1% each), during evening-to-night hours (41.6%), and during weekends (42%). Most offenders (91.2%) were men, elder than victims, with heavy motor vehicles (91.2%) being the culprit vehicle. Rash driving led to most deaths (53.2%).

Entanglement of near-surface optical turbulence to atmospheric boundary layer dynamics and particulate concentration: implications for optical wireless communication systems

Localized reduction in optical turbulence due to enhanced atmospheric heating caused by the solar absorption of aerosol black carbon (BC) is reported. Immediate response of atmospheric turbulence to BC-induced atmospheric warming strongly depends on the available solar radiation (time of the day), BC concentration, and atmospheric boundary layer dynamics. Besides the significant climate implications of a reduction in turbulence kinetic energy, a large reduction in the refractive index structure parameter (Cn2) resulting from BC-induced warming would affect the atmospheric propagation of laser beams. Interestingly, aerosols contribute significantly (up to 25%) to the signal deterioration in optical wireless communication systems during convectively stable atmospheric conditions when higher signal-to-noise ratios are expected otherwise due to the reduced thermal convection. Competing effects of the fractional contributions of aerosol extinction and scintillations on beam attenuation are reported; daytime being largely dominated by scintillation effects while the nighttime being dependent on the ambient aerosol concentration as well. We put forward the entanglement of optical turbulence to aerosol concentration, atmospheric boundary layer dynamics, and surface-reaching solar radiation, and discuss the possible implications for optical propagation.

Performance of free-space optical communication systems: effect of aerosol-induced lower atmospheric warming

We report the effect of aerosol-induced local atmospheric heating and the resulting changes in the lower atmospheric optical turbulence on the performance of Free-Space Optical (FSO) communication links. A closed form mathematical expression is derived to estimate the influence of aerosol-induced warming on the Bit Error Rate (BER) of a Binary Phase Shift Keying FSO communication link through Gamma-Gamma modeled turbulence. Our results demonstrate a strong impact, with the aerosol-induced turbulence taking a toll on the signal-to-noise ratio of ~20 dB for a BER of 10^-9. Aerosol-induced warming produces significant variations in BER compared to the clear atmospheric conditions and can subdue the benefits of improved beam alignment.

Distinctive roles of elevated absorbing aerosol layers on free-space optical communication systems

The impact of enhanced local heating due to absorption of solar radiation by elevated layers of aerosol black carbon (BC) in the lower troposphere in the performance of free-space optical (FSO) communication links is investigated. It is seen that a strong elevated BC layer at an altitude around 4.5 km enhances the atmospheric stability locally and leads to a large reduction in the atmospheric refractive index structure parameter (Cn2), leading to improved performance of the FSO communication links. For layers in the tropical atmosphere with sufficiently high BC concentration, the signal attenuation due to BC absorption is alleviated by the large reduction in Cn2 due to BC-induced warming and brings down the link outage probability. Synergy between reduction in Cn2 and long wavelength transmission improves the link budget significantly by reducing the beam wander and number of adaptive optics units required.

Trabeculectomy training in England: are we safe at training? Two year surgical outcomes

OBJECTIVES

To define the safety profile of trainee trabeculectomy surgery in the United Kingdom. Surgical exposure for trainees in England is limited due to service requirements, the European working time directive constraints and increasing sub-specialisation of glaucoma surgery. Limited knowledge exists on the outcomes of supervised glaucoma surgery. The aim is to determine the safety of supervised trabeculectomy surgery performed by trainee ophthalmologists.

METHODS

Retrospective case note review of all patients that had trabeculectomy surgery with MMC by consultant and trainee surgeons across multiple UK centres. All eyes have 2-year follow up. Success was determined using WGA guidelines. Two-tailed p values were obtained using Fisher's exact test to ascertain statistical significance between groups.

MAIN OUTCOME MEASURES

intraocular pressure, visual acuity, success and failure rates.

RESULTS

324 eyes were reviewed. 211 (66.4%) cases were performed by glaucoma consultants, 107(33.6%) by trainee ophthalmologists. The majority of eyes in each group were undergoing surgery for POAG. Post-operative IOP control showed no significant difference between consultant and trainee groups at year 1 and year 2. Success rates showed no significant difference between consultant and trainee cases. Failure rates at year 1 showed a significant difference between the two groups. No significant difference was seen at year 2. The trainee group had significantly more complications, when compared with the consultant group. Snellen visual acuity loss was not statistically significant between the two groups at the 2 year time point.

CONCLUSIONS

The outcomes of supervised trainee trabeculectomy compare favourably with consultant cases after 2 year follow up. Trainee cases had higher complication rates than consultant cases. Bleb leaks are a common complication of trainee cases, where closer supervision may be required. There is potential for surgical simulation to help increase the success of such cases. These findings may encourage trainee participation in glaucoma surgery.

Dependence of atmospheric refractive index structure parameter (Cn2) on the residence time and vertical distribution of aerosols

Effects of absorbing atmospheric aerosols in modulating the tropospheric refractive index structure parameter (Cn2) are estimated using high resolution radiosonde and multi-satellite data along with a radiative transfer model. We report the influence of variations in residence time and vertical distribution of aerosols in modulating Cn2 and why the aerosol induced atmospheric heating needs to be considered while estimating a free space optical communication link budget. The results show that performance of the link is seriously affected if large concentrations of absorbing aerosols reside for a long time in the atmospheric path.

Preventing childhood obesity in Latin America: an agenda for regional research and strategic partnerships

The increasing prevalence of childhood obesity in Latin America poses a major public health challenge to the region. In response, many countries are implementing obesity prevention programmes aimed at modifying known risk factors. However, the limited scientific evidence inhibits the development and implementation of novel, effective interventions across the region. To address these gaps, the NIH Fogarty International Center convened a workshop of researchers, policymakers, programme implementers and public health advocates who are actively engaged in the region to prevent childhood obesity. Major aims of the meeting were to define the current status of childhood obesity, identify the scientific gaps in our understanding of the epidemic, point out the barriers and opportunities for research and outline a plan for capacity building in the region in the area of childhood obesity. This series of articles reflects the key outcome of the meeting and offers an analysis of the knowledge translation needed for evidence-based policy initiatives, a review of the research agenda and an evaluation of research capacity in the region. The goal of the papers is to inform the development of multidisciplinary and multisector research collaborations, which are essential to the implementation of successful childhood obesity prevention strategies in the region.

Deep sclerectomy for uveitic glaucoma: long-term outcomes

PurposeTo report long-term outcomes of deep sclerectomy (DS) in eyes with raised intraocular pressure (IOP) and glaucoma secondary to uveitis.Patients and methodsRetrospective consecutive case series of 43 eyes of 43 patients with uveitic glaucoma. Mitomycin C (MMC) 0.2-0.4 mg/ml was applied sub-conjunctivally prior to scleral flap dissection for 2-3 min in 35 eyes (81%). Combined phacoemulsification and DS was done in 4 cases (9%).ResultsMean follow-up was 68.5±33.5 months. In total, 23 eyes (53.5%) had previous intraocular surgery. Pre-operative IOP was 33.6±12.0 mm Hg. Mean IOP at one, three and five years after surgery was 15.5±5.0 mm Hg, 16.9±6.7 mm Hg and 16.4±5.2 mm Hg, respectively.The probability of IOP <22 and <19 mm Hg was 69 and 62% at 3 years and 60 and 51% at 5 years, respectively. This included eyes that had undergone needle revision and/or laser goniopuncture within that period but had not needed glaucoma medication or further glaucoma procedures. The overall number of glaucoma medications decreased from 3.0±1.2 to 0.8±1.2 by last follow-up (P<0.001). Serious complications included hypotony with macular folds in two eyes and occlusion of the trabeculo-Descemet's membrane (TDM) by iris in two eyes. Recurrence of uveitis was observed in 16 eyes. Seven eyes (16.3%) had subsequent procedures including trabeculectomy with MMC in one eye, DS with MMC in two eyes and Baerveldt tube implantation in five eyes.ConclusionsDS is a safe and effective procedure to lower IOP in uveitic glaucoma. However, as with other glaucoma procedures, a significant proportion of patients will require another IOP-lowering procedure in the long-term.

Correlating CD4 count with mucocutaneous manifestations in HIV-positive patients: A prospective study

Background:

Mucocutaneous findings may be the presenting symptoms in HIV-afflicted individuals. A multitude of mucocutaneous diseases also occurs during the course of the ailment, with some conditions being classed as disease defining. They include infectious diseases and noninfective inflammatory and neoplastic dermatoses. With progressive fall in CD4 count, there is a change in the types of mucocutaneous lesions encountered.

Aim:

This study aims to statistically correlate the CD4 counts with the mucocutaneous manifestations in 100 HIV-positive patients.

Materials and Methods:

A total of 100 cases of HIV-positive patients with skin and mucous membrane manifestations were selected serially. A complete history was taken, clinical examination was done, and the CD4 count was noted. Patients were divided into four groups (Groups I, II, III, IV) with different ranges of CD4 values, namely, <50, 50–200, 201–500, >500, respectively.

Results:

The distribution of study population in CD4 ranges showed that majority (47%) of the study population had CD4 count between 201 and 500, and 29% of the study group had CD4 count between 50 and 200 cells. Almost 21% of the patients had the count > 500 cells and 3% had cell count < 50. Majority of the infectious and non-infectious dermatoses were common in the CD4 count between 201–500 (Group III) and 50–200 (Group II). In the study groups, 52 cases (52%) were on antiretroviral therapy (ART), and the remaining 48 cases (48%) were not on ART at the time of diagnosis of mucocutaneous manifestations. Out of 48 ART-naïve cases, 23 patients were screened and newly diagnosed at the outpatient department (OPD) based on the mucocutaneous manifestations. Most of the patients with multiple mucocutaneous conditions were in the CD4 count <200, whereas single manifestation was seen predominantly in CD4 count >200.

Conclusion:

Statistically significant association with the CD4 count was seen in herpes zoster ophthalmicus, genital wart, genital herpes, vaginal discharge syndrome, scabies, pyoderma, dermatophytosis, Hansen's disease, herpetic gingivostomatitis, seborrhoeic dermatitis, lichen planus, and drug reactions. These dermatoses may indicate the worsening of immune status and the need for regular monitoring with periodical CD4 counting. Occurrence of dermatoses such as photosensitive eczema, drug reaction, lichen planus, Type I lepra reaction, and herpes zoster ophthalmicus in patients on ART may be due to IRIS. To avoid the more frequent occurrence of infectious dermatoses and to reduce the development of IRIS with ART, all HIV-positive cases may be started on ART at higher CD4 count. Screening for HIV infection is suggested whenever the following conditions are seen: persistent oral candidiasis, atypical manifestations of zoster, herpes zoster ophthalmicus, herpetic gingivostomatitis and MC in adults, exaggerated IBA, and extensive seborrhoeic dermatitis.

Role of music and non-musical techniques in self-guided emotional regulation

Introduction

Studies on relationships between music, visual imagery or therapeutic techniques, like mindfulness and emotions have been undertaken with varying success in predominantly adult populations. Their role in the child and adolescent population remains unclear.

Aims and objectives

We undertook a systematic literature review to assess current evidence in the use of music, guided imagery with/without therapeutic techniques for emotional processing in adults, children and adolescents.

Methods

We identified 87 relevant papers (JSTOR, OVID Medline, Cochrane, PubMed, Science Direct, Taylor & Francis and Wiley). We excluded non-English papers and qualitative analyses. Nine studies used quantitative techniques (Neuroimaging) for assessing emotional change using musical and non-musical stimuli (n = 77). Of these, four studies used fMRI and two used PET scans.

Results

fMRI demonstrates a significant relation between amygdalar activation and emotional response to visual imagery (P < 0.05, n = 45). Early information using PET scanning shows a significant association between activation of different parts of brain with varied visual imagery (one study, n = 5) and varied music (one study, n = 10). There is similarity in the activation of specific cortical areas using musical and non-musical stimuli. Two separate studies of patients with damaged amygdala due to disease (n = 6) showed significant impairment of emotional processing and response.

Conclusions

There is early encouraging data providing evidence of possible relationships between music and visual imagery in emotional processing. Further studies are needed to examine these in detail, especially in children/adolescents. Music with visual imagery may be a useful adjunct in the self-guided processing of milder emotional disorders with components of anxiety, depression, adjustment and emotional dysregulation.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Gastric intestinal metaplasia - age, ethnicity and surveillance for gastric cancer

AIM

Determine the prevalence and distribution of gastric intestinal metaplasia (GIM) in a large cohort of patients subjected to esophagogastroscopy (EGD). Evaluate usefulness of grading the severity of gastritis, GIM and the impact of Helicobacter pylori (HP). Define the population at risk for gastric adenocarcinoma (GC) and assess the value of surveillance.

METHODS

In the course of 19 years, we performed 11,600 sequential EGDs in male veterans at Brooklyn, New York. Of all patients, 47 % had EGD only one time while 53 % had EGD repeated, 11 % of these had four or more EGDs. Patients with GIM were matched with equal number of controls with no GI symptoms. All gastric biopsies were processed in one laboratory, using the standardized protocol for histological staining and for grading the severity of epithelial changes.

RESULTS

Of all patients subjected to EGD, 354 (3.05 %) were diagnosed with GIM. Compared to controls, GIM patients were older, 80 % were over 71. Regarding ethnicity, GIM was 5.4 % more frequent in 177 African Americans than in 159 Caucasians. Distribution of GIM did not differ with respect to age or ethnicity. As many as 6 %of GIM cases were diagnosed with GC. Grading of GIM severity had a predictive value, the average grade of severity in GC was 50 % higher than in non-cancer patients with GIM. Severity of gastritis was also a useful biomarker: patients with GC had more severe gastritis. Surprisingly, HP positivity had no predictive value: HP positive patients had similar distribution of GIM as the HP negative patients. Use of proton pump inhibitors in the past was unknown.

CONCLUSION

Prevalence of GC in patients with GIM was more than 200 times higher than reported in normal population. Age more than 70 years and African Americans appeared to be at higher risk. Routine EGD and histological diagnosis, with simple grading of severity of epithelial changes provides a useful predictive information. Individuals with upper GI symptoms undergoing EGD with gastric biopsy benefited from routine clinical screening for GC. Patients with higher severity of GIM should enter surveillance (Tab. 1, Fig. 10, Ref. 45).

Cytodiagnosis of Sacral Chordoma

We report the cytological findings of a sacro-coccygeal chordoma in a 53 year male diagnosed preoperatively by guided fine needle aspiration cytology. The smears shows characteristic Physalliphorous cells in a metachromatic background of myxoid material entrapping cords of cuboidal cells. Differential diagnosis in cytology include conventional and myxoid chondrosarcoma, myxoid liposarcoma, myxoid malignant fibrous histiocytoma(MFH), metastatic mucinous carcinoma and myxo-papillary ependymoma. The distinguishing features between these neoplasms are discussed. Preoperative diagnosis of chordoma permits optimum planned surgery.

The Process of Team Boundary Spanning in Multi-Organizational Contexts

Work teams must increasingly operate in complex environments characterized by multiple external actors beyond team and organizational boundaries. Although previous research demonstrates the importance of boundary spanning activities to team effectiveness, it reveals relatively little about the process of boundary spanning in these environments. In this article, we investigated the processes of boundary spanning across multiple external actors in 10 cross-organizational teams. We identified three sequences for reaching out to external actors: (a) moving inside-out from vertical actors inside the host organization to horizontal actors outside of the host organization, (b) moving outside-in from horizontal actors to vertical, and (c) staying-inside with vertical actors from the host organization. Our observations suggest that inside-out and outside-in sequences were more successful than simply pleasing the host organization. We build on our empirical findings to develop a process theory of how team boundary spanning activities across multiple external actors influence team effectiveness. Our research underscores the importance of a team’s interactions with actors in its external environment beyond those in an immediate supervisory role and provides insight into the dynamics of boundary spanning in multi-organizational contexts.

A rare case of a solitary intraocular neurofibroma

BACKGROUND

Solitary neurofibroma in the absence of neurofibromatosis is of rare occurrence and very few cases have been reported till date.

OBJECTIVE

To report a case of a solitary intra-ocular neurofibroma.

CASE

A 65-year-old man presented to us with a large swelling appearing to arise from right pthisical eye for the past one and a half years. After knowing the extent and origin of mass lesion, right eyeball was enucleated and subjected to histopathological examination which revealed intraocular neurofibroma in the absence of neurofibromatosis which is of very rare occurrence.

CONCLUSION

The isolated neurofibroma of intraocular origin can present as an isolated orbital mass without systemic features.

Deep sclerectomy with mitomycin C in eyes with failed glaucoma surgery and pseudophakia

PURPOSE

To report outcomes of deep sclerectomy (DS) with intraoperative mitomycin C (MMC) application in eyes with previous failed glaucoma surgery (GS) and/or cataract extraction (CE).

PATIENTS AND METHODS

Single-surgeon case series of 82 eyes of 82 patients undergoing DS with MMC. The patients had previous CE with IOL and/or conjunctival GS and treated intraocular pressure (IOP) >18 mm Hg. MMC (0.2 mg/ml) was applied for 2-3 min before scleral flap dissection. Complete success was defined as IOP between 6 and 21 mm Hg or a reduction of 20% from baseline without medications. Reoperation for glaucoma or related complications, or loss of light perception vision was considered as failure.

RESULTS

Mean follow-up was 57.7 ± 22.4 months with 78% of patients completing the 3-year follow-up. Mean IOP decreased from 24.0 mm Hg (22.3-25.6, 95% confidence intervals) to 13.4 mm Hg (12.0-14.2) at 3 years after surgery (P<0.001). There was a significant decrease in the number of glaucoma medications from 2.0 ± 1 preoperatively, to 0.3 ± 0.7, 3 years after surgery. Kaplan-Meier cumulative success rates were 85.6% at 1 year, 80.0% at 2 years, and 76% at 3 years. At 3 years, IOP was maintained <19 and 15 mm Hg in 83 and 70% of eyes, respectively. Fourteen eyes (17.1%) had complications. Delayed hypotony (IOP <6 mm Hg) was the commonest complication in five eyes (6.1%).

CONCLUSION

DS with MMC appears to be a safe and effective surgical procedure for eyes with previous intraocular surgery.

Combined phacoemulsification and deep sclerectomy (PDS) with intraoperative mitomycin C (MMC) augmentation

AIM

To report the safety and efficacy of intraoperative mitomycin (MMC) augmentation of combined phacoemulsification and deep sclerectomy (PDS).

METHODS

Retrospective, non-randomized, comparative, interventional case series of 119 eyes (63 with and 56 without MMC augmentation) of 119 patients who had PDS between September 2001 and April 2004.

RESULTS

The mean follow-up was 23 months (range 12-41 months). There were no differences in the baseline characteristics of the two groups except that patients from the phacoemulsification and deep sclerectomy with mitomycin C (PDS-MMC) group were on average, younger by 3 years (P=0.01). Two years after surgery, the probability of maintaining an IOP below 19 and 15 mmHg without glaucoma medications or needle revision was 76 and 62% in the PDS-MMC group and 62 and 45% in the PDS-no MMC group (P=0.02 and 0.04, respectively). Nd:YAG laser goniopuncture was performed in 71.4% of eyes in the PDS-no MMC and 61.9% of the PD-MMC group (P=0.33). Needle revision was performed in 21.4% of the PDS-no MMC and 17.4% of the PDS-MMC group (P=0.65). Ten patients (8.4%) lost more than two lines of Snellen's visual acuity during follow-up, with no difference between the groups. There were few serious complications related to MMC use (hypotony in one eye after laser goniopuncture). The overall incidence of transconjunctival oozing in the PDS-MMC group was 9.5% compared with 5.4% in the PDS-no MMC group.

CONCLUSION

This study demonstrates that augmentation of PDS with MMC is safe. MMC augmentation appears to increase the probability of achieving lower target intraocular pressures after combined PDS.

Sudden asystole during surgery in the cerebellopontine angle

We report a case of a 40-year-old lady undergoing surgery for a tumor in the cerebellopontine angle. Intraoperatively, patient had a sudden asystole without prior warning sign of bradycardia. It could have been the severe form of trigeminocardiac reflex. The cardiac rhythm returned spontaneously once the surgical manipulation stopped. The remainder of the operation was uneventful and no complication occurred afterwards. The possible mechanism of the event is discussed.

Deep sclerectomy and low dose mitomycin C: a randomised prospective trial in west Africa

AIM

To study the efficacy and safety of deep sclerectomy (DS) augmented with intraoperative low dose mitomycin C (MMC) in a west African population.

METHODS

Prospective, randomised, controlled trial. Trial participants were Nigerian patients with medically uncontrolled primary open angle glaucoma undergoing primary surgery at Maja Hospital, Lagos, Nigeria. 39 eyes of 39 patients undergoing DS were randomised into receiving intraoperative MMC 0.25 mg/ml for 2 minutes at the end of procedure (DS-MMC) and a control group (DS-noMMC).

RESULTS

There were 21 patients in the DS-noMMC and 18 in the DS-MMC group with no difference in the preoperative characteristics of the groups. Mean follow up was 16.4 (SD 11.3) months. The probability of maintaining an intraocular pressure less than 18 mm Hg with or without additional medications (95% confidence intervals) at 1 year was 70% (47-92%, 95%) and 79% (57-100%), and at 18 months was 35% (8-62%) and 38% (7-69%) for the DS-noMMC and DS-MMC groups, respectively, with no difference in success rates (p = 0.6). An IOP of less than 18 mm Hg without additional medication was maintained in 65% (41-89%) and 73% (49-96%) at 1 year and 24% (8-48%) and 13% (13-46%) at 18 months for the DS-noMMC and DS-MMC groups, respectively (p = 0.5). There were no serious complications related to the procedure.

CONCLUSIONS

The success rates of DS in black west African glaucoma patients, as performed in this study, were low. The study did not achieve sufficient power to detect whether low dose intraoperative MMC application can increase success rates of DS.

Mitomycin C augmented glaucoma surgery: evolution of filtering bleb avascularity, transconjunctival oozing, and leaks

AIMS

To prospectively study the evolution of possible high risk features of conjunctival filtration blebs like avascularity, transconjunctival oozing (TCO), and leaks after mitomycin C (MMC) enhanced glaucoma surgery.

METHODS

Single observer, 2 year prospective study on bleb characteristics of 125 eyes of 125 consecutive patients who had MMC augmented glaucoma surgery with initially successful filtration. MMC (0.2 mg/ml for 2 minutes in most cases) was applied on the area of the scleral flap before dissection. Glaucoma surgeries included were trabeculectomy, deep sclerectomy, and combined procedures. A dry fluorescein strip was applied on the avascular part of the bleb and observed for aqueous egress with flow (point leak, PL) or without (TCO).

RESULTS

The mean time (95% CI) for observing bleb avascularity, TCO, and bleb leaks were 106 days (69 to 143), 208 days (155 to 261), and 609 days (559 to 659), respectively. Bleb leaks were observed in 17 eyes (13.6%)-15 (24.6%) in the trabeculectomy group and two (3.1%) in the deep sclerectomy group (p = 0.003). Kaplan-Meier survival analyses showed that the probability of observing bleb avascularity at sixth, 12th, and 24th month after surgery was 56%, 71%, and 73%, respectively. In eyes with avascular blebs, the probability of developing TCO and leaks was 77% and 1% at 6 months, 81% and 12% at 12 months, and 95% and 26% at 24 months, respectively. Cox's regression analyses and log rank tests showed that eyes with larger avascular blebs (>4 mm) were more likely to develop TCO (hazard ratio 3.77, p = 0.001) and delayed bleb leaks were more likely to be seen in eyes of the trabeculectomy group rather than the deep sclerectomy group (hazard ratio 0.06, p = 0.0006).

CONCLUSIONS

MMC application over the area of scleral flap dissection during glaucoma surgery is associated with a high incidence of bleb avascularity, TCO, and delayed bleb leaks. Most eyes developed bleb avascularity within the first year after surgery. TCO will eventually be seen in all eyes with avascular blebs and the incidence of leaks gradually increases with time. This study shows that patients with eyes undergoing glaucoma surgery with MMC and avascular blebs should be monitored indefinitely.

Combined cataract and glaucoma surgery with mitomycin C: phacoemulsification-trabeculectomy compared to phacoemulsification-deep sclerectomy

AIMS

To compare outcomes of phacoemulsification combined with trabeculectomy (PT) or deep sclerectomy (PDS) with intraoperative mitomycin C (MMC) application.

METHODS

Non-randomised, consecutive, retrospective comparative study. 97 eyes of 97 patients (59 PDS, 38 PT) undergoing combined surgery with intraoperative MMC (0.1-0.4 mg/ml for 1-3 minutes) were identified for inclusion in the study.

RESULTS

The probability of maintaining intraocular pressure (IOP) below 19 mm Hg and 15 mm Hg, with a 30% drop from preoperative IOP and without additional medication, 1 year after surgery were 77.6% (95% CI: 67 to 90) and 71.5% (60 to 85) for the PDS group and 89.5% (80 to 99) and 89.5 (80 to 99) for the PT group, respectively, and these differences were not statistically significant (p>0.05, log rank test). After excluding ocular co-morbidity no differences were observed in the improvement of visual acuity between the two groups. There were no major differences in the complication rates except that delayed bleb leaks were seen in seven eyes (18.4%) of the PT group (p = 0.004).

CONCLUSION

In this study, no statistically significant difference was found in the IOP and visual outcomes between PDS and PT. A significantly higher frequency of late bleb leaks after PT was observed.

Deep sclerectomy augmented with mitomycin C

AIMS

To investigate the comparative efficacy and safety of deep sclerectomy with and without intraoperative mitomycin C (MMC) application for lowering the intraocular pressure (IOP).

METHODS

A total of 71 eyes of 71 consecutive patients who had routine deep sclerectomy (DS), nonaugmented (DS-noMMC) or with mitomycin C (DS-MMC) augmentation (0.2 mg/ml for 2 min) and follow-up of 4 months or more were identified from an ongoing prospective database on glaucoma surgery. Indications for MMC use were the presence of risk factors for subconjunctival scarring and low target IOPs. MMC 0.2 mg/ml was applied in the sub-Tenons space for 2 min.

RESULTS

There were 19 eyes in the DS-noMMC group and 52 eyes in the DS-MMC group. In 11 eyes (15.5%), the procedure was complicated by intraoperative perforation of the trabeculo-Descemet's window. Eyes in the DS-MMC group had significantly lower IOPs (MANOVA, P = 0.04). Kaplan-Meier survival curve analysis showed that the probability of maintaining IOP below target IOP level, below 18 mmHg and below 14 mmHg at 1 year was 51, 67, and 35% for the DS-noMMC group and 80, 86, and 74% for the DS-MMC group. The survival rates of the DS-MMC group were not statistically significant (P = 0.06) when the success criterion was maintaining an IOP less than 18 mmHg but were significant for the other criteria, namely IOP less than target levels (P = 0.03) and less than 14 mmHg (P = 0.03). Nd:YAG goniopuncture to lower IOP to target levels was done more frequently in the DS-noMMC group (13 eyes, 81%) than the DS-MMC group (20 eyes, 45%) and this difference was significant (P = 0.03). The prevalence of avascular areas within filtration blebs and transconjunctival oozing of aqueous was significantly higher in the DS-MMC group (P < 0.01).

CONCLUSIONS

The use of intraoperative MMC during deep sclerectomy has a significant effect on the postoperative IOP and increases the probability of achieving target IOPs. However, our current technique of MMC application is associated with a higher incidence of avascular blebs and transconjunctival oozing.