Association between Increased Uterine Activity, as Recorded Noninvasively from the Anterior Abdominal Wall at 34 Weeks' Gestation, and Preterm Birth

Background

There is a need to accurately identify pregnant women at risk for preterm birth as early as possible. Recent developments in technology enable the recording of uterine electrical activity (electrohysterogram) from the anterior abdominal wall in a non-invasive way.

Objective

To investigate whether uterine activity recorded under resting conditions at a gestational age of 34 weeks could identify a risk of preterm birth.

Study design

A commercial antenatal holter device with its dedicated software was used to record and store raw data of the maternal and fetal electrocardiograms and uterine activity for the Safe Passage Study. Uterine activity was recorded under resting conditions from 34 weeks' gestation in epochs of 250 ms (millisecond) for at least 30 min. From this database the raw data, recorded at a mean gestational age of 34 weeks, of 50 women who had preterm deliveries were selected for comparison with data of women who had term deliveries. Mean uterine activity, expressed in microvolt (μV)/epoch, was used for the comparison.

Results

After exclusion of 25 participants where labour was induced or augmented and another three for other reasons, 36 remained in each group. The participants in each group were comparable in respect of maternal age, gravidity, parity, gestational age at recruitment and duration of recording. Uterine activity in the preterm group (60.3 μV/epoch) differed significantly (p<0.01) from that of the comparison group (52.4 μV/epoch). Using a cut-off point of 52.3 μV/epoch as obtained from receiver operator characteristic curves (area under the curve 0.72), the sensitivity and specificity of identifying risks of preterm labour were 81% and 50% respectively.

Conclusion

Results of this small study are promising but need to be confirmed in larger studies and preferably at earlier gestational age.

Accelerations of the Fetal Heart Rate in the Screening for Fetal Growth Restriction at 34-38 Week's Gestation

OBJECTIVES

To use machine learning to determine what information on Doppler velocimetry and maternal and fetal heart rates, collected at 20-24 weeks gestation, correlates best with fetal growth restriction according to the estimated fetal weight at 34-38 weeks.

STUDY DESIGN

Data of 4496 pregnant women, collected prospectively for the Safe Passage Study, from August 2007 to August 2016, were used for the present analysis. Doppler flow velocity of the uterine, umbilical, and middle cerebral arteries and transabdominally recorded maternal and fetal ECGs were collected at 20-24 weeks gestation and fetal biometry collected at 34-38 weeks from which the estimated fetal weight was calculated. Fetal growth restriction was defined as an estimated fetal weight below the 10th centile. Accelerations and decelerations of the fetal and maternal heart rates were quantified as gained or lost beats per hour of recording respectively. Machine learning with receiver operative characteristic curves were then used to determine which model gives the best performance.

RESULTS

The final model performed exceptionally well across all evaluation metrics, particularly so for the Stochastic Gradient Descent method: achieving a 93% average for Classification Accuracy, Recall, Precision and F1-Score to identify the fetus with an estimated weight below the 10th percentile at 34-38 weeks. Ranking determined that the most important standard feature was the umbilical artery pulsatility index. However, the excellent overall accuracy is likely due to the value added by the pre-processed features regarding fetal gained beats and accelerations.

CONCLUSION

Fetal movements, as characterized by gained beats as early as 20-24 weeks gestation, contribute to the value of the flow velocimetry of the umbilical artery at 34-38 weeks in identifying the growth restricted fetus.

Smoking and drinking habits of women in subsequent pregnancies after specific advice about the dangers of these exposures during pregnancy

BACKGROUND

Although women are informed about the dangers of drinking and smoking during pregnancy when they book for antenatal care, it is uncertain whether this advice is accepted, or whether attempts are made to apply it in subsequent pregnancies.

OBJECTIVES

To assess how pregnant women respond to the advice to refrain from smoking and drinking during pregnancy in subsequent pregnancies.

METHODS

Research staff were trained to obtain accurate prospective information on smoking and drinking during pregnancy in a prospective study, using well-standardised methods. Care was taken to inform participants about the dangers of smoking and drinking during pregnancy. They were also given pamphlets on these dangers in their own language and a list of telephone numbers where they could find help to quit should they need it. This information was repeated at subsequent study visits (ranging from 1 to 3, depending on the gestational age at which they enrolled). Gestational age was determined by early ultrasound. Z-scores of birthweight for gestational age were determined according to the INTERGROWTH-21st study. Pregnancy outcomes of women who enrolled twice (n=888) or three times (n=77) in the Safe Passage Study were compared with those of women in the first enrolment (n=889).

RESULTS

The proportion of drinkers did not change significantly (p=0.058) from the first to the second and third enrolments (63.8%, 59.0% and 54.6%, respectively). A similar trend was found for smokers (73.3%, 72.2% and 68.4%, respectively). Cannabis use was reported by 15.1%, 9.7% and 12.0% (p<0.005) of women, respectively, and use of methamphetamine by 10.1%, 6.6% and 12.7% (p<0.005). There was an increase in the rate of preterm births from 15.5% to 17.5% and 24.7%, respectively, but the increase was not significant. Although mean birthweight was lower in the third enrolment compared with the second, the difference was not significant. The z-score of birthweight for gestational age was significantly lower in the second enrolment compared with the first.

CONCLUSIONS

Detailed information on the adverse effects of smoking and drinking during pregnancy was not effective in the population studied. Other methods to reduce or stop these toxic exposures should therefore be investigated. A short inter-pregnancy interval, as demonstrated by three enrolments in 7.5 years, is associated with preterm labour and fetal growth restriction, and is probably indicative of the role played by confounders such as poor socioeconomic conditions and drug exposure during pregnancy.

Axillary lymph node dissection for patients with invasive breast cancer at Charlotte Maxeke and Chris Hani Baragwanath Academic Hospitals

BACKGROUND

The extent of axillary surgery correlates with its morbidity and sentinel lymph node biopsy (SLNB) has become the standard of care in clinically node-negative (cN0) patients.This study aims to evaluate the application of SLNB and axillary lymph node dissection (ALND) and the associated risk factors for node-negative ALND in our units.

METHODS

We included female patients with primary breast cancer who underwent axillary surgery in the breast units at Charlotte Maxeke Johannesburg Academic Hospital and Chris Hani Baragwanath Academic Hospital from March 2013 to March 2015. Univariate and multivariable logistic regression models were used to determine factors associated with pathological node-negative (pN0) ALND.

RESULTS

505 patients were included and 344 patients were staged clinically node-positive (68.1%), 161 (31.9%) were assessed as clinically node-negative and deemed eligible for SLNB. Sensitivity of clinical nodal staging was 85.9% with a positive predictive value of 76.5%. The majority of patients (313, 61.9%) underwent primary surgery while 192 (38.1%) underwent surgery after NACT. We performed 118 SLNBs and 387 ALNDs of which 97 were pathologically node-negative. Risk was not increased after NACT (OR 1.06, p = 0.790). We identified a significant risk in patients with triple-negative and HER-2 enriched subtypes compared to hormone receptor-positive patients (OR 3.05, 95% CI: 1.6-5.7, p = 0.001 and OR 2.25, 95% CI: 1.1-4.8, p = 0.035).

CONCLUSION

The prevalence of pN0 ALND was 25.06%. In our cohort a significantly higher risk was found in hormone receptor-negative tumours. Preoperative nodal assessment needs to be optimised and include pathological confirmation. SLNB needs to be extended to patients after NACT despite resource-constraints.

Effects of alcohol, cigarettes, methamphetamine and marijuana exposure during pregnancy on maternal serum alpha-fetoprotein levels at 20-24 weeks'gestation

OBJECTIVE

To examine the effects of cigarette, marihuana and methamphetamine smoking and consumption of alcohol during pregnancy on maternal serum alpha-fetoprotein (MSAFP) levels at 20-24 weeks.

STUDY DESIGN

In the Safe Passage Study (SPS) more than 12,000 pregnant women were prospectively followed up during pregnancy and until the infant was one year old to examine the effects of exposure to alcohol during pregnancy on stillbirth and sudden infant death syndrome. The present study is a cross-sectional secondary analysis of MSAFP analyses done at 20-24 weeks gestation in 1,679 SPS participants, recruited at the Bishop Lavis Community Health Centre, Cape Town, South Arica.

RESULTS

Low or moderate alcohol consumption with or without smoking, nor methamphetamine or marihuana use affected mean MSAFP levels. High MSAFP levels were associated with high alcohol consumption, young age, low body mass index (BMI) (<18 kg/m²) or small mid upper arm circumference (MUAC) (<230mm). High MSAFP levels were associated with stillbirth, preterm birth, abruption and a birth weight z-score of less than -1.

CONCLUSION

The study confirms the association between high MSAFP levels and adverse pregnancy outcomes but, although exposure to smoking or drinking is associated with adverse pregnancy outcomes including stillbirth, MSAFP levels were not affected by any of these exposures except for continued high consumption of alcohol. The observed association between higher MSAFP levels and maternal nutritional status (as demonstrated by the lower MUAC and BMI) could explain some of the correlations of poor socioeconomic conditions with higher stillbirth rates effect.

Fetal heart rate patterns at 20 to 24 weeks gestation as recorded by fetal electrocardiography

INTRODUCTION

With advancing technology it has become possible to accurately record and assess fetal heart rate (FHR) patterns from gestations as early as 20 weeks. The aim of our study was to describe early patterns of FHR, as recorded by transabdominal fetal electrocardiogram according to the Dawes-Redman criteria. Accordingly, short-term variability, basal heart rate, accelerations and decelerations were quantified at 20-24 weeks gestation among women with uncomplicated pregnancies.

METHODS

This study was conducted in a subset of participants enrolled in a large prospective pregnancy cohort study. Our final data set consisted of 281 recordings of women with good perinatal outcomes who had undergone fetal electrocardiographic assessment as part of the Safe Passage Study.

RESULTS

The success rate of the recordings was 95.4%. The mean frequency of small and large accelerations was 0.5 and 0.1 per 10 min, respectively and that of small and large decelerations 0.3 and 0.008 per 10 min, respectively. The mean and basal heart rates were both equal to 148.0 bpm at a median gestation of 161 days. The mean short term variation was 6.2 (SD 1.4) ms and mean minute range 35.1 (SD 7.1) ms.

CONCLUSION

The 20-24-week fetus demonstrates FHR patterns with more accelerations and decelerations, as well as higher baseline variability than was anticipated. Information from this study provides an important foundation for further, more detailed, studies of early FHR patterns.

Effects of radiotherapy on uveal melanomas and adjacent tissues

Most uveal melanomas are treated with radiotherapy. An adequate understanding of the effects of radiation on the tumour and the healthy ocular tissues is necessary. Ionizing radiation damages cell membranes, organelles, and DNA. Irradiated cells are lysed or undergo apoptosis, necrosis, and senescence. These effects occur in tumour cells and vascular endothelial cells, resulting in tumour shrinkage, ischaemia, infarction, exudation, and fibrosis, which can cause exudative maculopathy, serous retinal detachment, rubeosis, and neovascular glaucoma (ie, 'toxic tumour syndrome'). Such abnormalities must be distinguished from collateral damage to healthy ocular tissues that receive high doses of radiation, and these include radiation-induced retinopathy, optic neuropathy, choroidopathy, cataract, and scleral necrosis. Radiation retinopathy can be treated effectively with photodynamic therapy, anti-angiogenic agents, and intravitreal steroid injections. In some patients, optic neuropathy may improve with intravitreal steroids or anti-angiogenic agents. Neovascular glaucoma resolves with intra-cameral bevacizumab. Exudative retinal detachment can regress with intra-vitreal steroid injections. Cataract is treated in the usual manner. Scleral necrosis, if severe, may require grafting, possibly using a lamellar flap from the same eye. Depending on the bulk of the residual toxic tumour, treatment can consist of intra-vitreal steroids and/or anti-angiogenic agents, transpupillary thermotherapy or photodynamic therapy to the tumour, or surgical removal of the tumour by endo- or exo-resection. Measures aimed at preventing collateral damage include eccentric placement of ruthenium plaques or iodine seeds and delivery of a notched proton beam. The decision to treat a uveal melanoma with radiotherapy requires the ability to manage iatrogenic side effects and complications.

Recognition and referral of girls with Attention Deficit Hyperactivity Disorder: case vignette study

BACKGROUND

Compared with boys, girls with Attention Deficit Hyperactivity Disorder (ADHD) are under-recognized. Parents commonly discuss concerns with teachers, who play an important role in the recognition and referral of children with ADHD. We investigated whether the predominating subtype of symptomatology influences teacher recognition of affected girls.

METHODS

A total of 212 teachers from 40 randomly selected primary schools in England participated in a postal questionnaire study. The questionnaire consisted of a case vignette (based on DSM-IV criteria) describing a girl with either combined or predominantly inattentive subtype ADHD. Each school received an equal number of each type of vignette for distribution. Further questions elicited teachers' conceptualization of the girl's difficulties and need for specialist referral, their views on treatment modalities and demographic data.

RESULTS

Most (98%) teachers recognized the presence of a problem but mainly conceptualized the girl's behaviour as reflecting attentional (89%) or emotional (62%) difficulties. Teachers were less likely to correctly identify a girl with inattentive than combined subtype ADHD (14% vs. 43%) or recommend clinical referral (50% vs. 59%) for her. Few (15%) teachers thought that medication might be helpful for a girl meeting diagnostic criteria for ADHD.

CONCLUSIONS

Teachers are able to recognize ADHD-related behaviours and impairments but conceptualize these as reflecting attentional or emotional difficulties rather than as relating to a disorder (ADHD). Teachers' conceptualization of ADHD and views about medication are important factors that could affect accurate recognition and referral. Improving teachers' knowledge about ADHD, especially the inattentive subtype, could assist in tackling gender-related barriers to care.

Visual loss following removal of intraocular silicone oil

AIM

To investigate the cause of visual loss following removal of intraocular silicone oil in patients who underwent vitrectomies for retinal detachment or giant retinal tear.

METHODS

The clinical records of three cases with visual loss following removal of silicone oil were reviewed. Investigations carried out included fundus fluorescein angiogram, optical coherence tomography, and electrophysiological studies.

RESULTS

Visual acuities dropped from 6/9 to 6/36 in two cases and 6/24 to 3/24 in the third. None of the three cases had macula detachment at any stage. Fundus fluorescein angiogram and optical coherence tomography were normal in all cases. Pattern electroretinogram showed reduced amplitudes of the P50 and N95 components. Multifocal electroretinogram indicated a selective damage to the central part of the macula.

CONCLUSIONS

The results suggest that the abnormality arises predominantly in the central part of the macula, especially the outer and middle layers. However, the exact mechanism still remains obscure.

A pilot study on the use of a perfluorohexyloctane/silicone oil solution as a heavier than water internal tamponade agent

AIMS

To report a prospective two centred non-comparative interventional pilot study of a solution of perfluorohexyloctane and silicone oil (Densiron-68) as a heavier than water internal tamponade.

METHODS

42 consecutive patients were recruited. The indications include proliferative vitreoretinopathy, retinal detachments arising from inferior retinal breaks, and inability to posture.

RESULTS

The success rate with one operation using Densiron was 81% and with further surgery 93%. At the end of the study all tamponade agents were removed in 90% of patients. Visual acuity improved from mean logMAR of 1.41 (SD 0.64) to 0.94 (SD 0.57), p = 0.001. There was little evidence of dispersion and excessive inflammation.

CONCLUSION

This new tamponade agent is being compared to conventional silicone oil in a prospective international randomised trial.

Case selection in macular relocation surgery for age related macular degeneration

BACKGROUND

To date there has been no randomised controlled trial demonstrating the safety and efficacy of macular relocation surgery (MRS) for age related macular degeneration (AMD). Vision can be improved in some patients and made worse in others despite successful surgery or because of complications.

PURPOSE

To determine which patients would benefit from MRS.

METHODS

Twenty nine patients with exudative AMD took part in a prospective, non-comparative, interventional study. Macular relocation surgery involved phacoemulsification, vitrectomy, 360 degrees retinotomy, excision of choroidal neovascular membrane, and macular relocation using an infusion of 5-fluorouracil and low molecular weight heparin as adjuvant to prevent proliferative vitreoretinopathy. Patients underwent protocol refraction preoperatively and six-monthly postoperatively by designated optometrists. Preoperative fundus fluorescein angiograms were read by masked observers and the lesions were classified according to a set protocol. The main outcome measures were visual improvement, final vision of better than 20/400, reading speed, critical print size. Logistic and multiple stepwise linear regressions were used to identify independent factors which predicted the main outcomes.

RESULTS

Preoperative visual acuity (20/120 or worse) and lesion type (predominantly classic or submacular haemorrhage) were significantly associated with visual improvement (coefficient of regression B = 26.8, p<0.001 and B = 14.9 with p = 0.045 respectively). There were no significant independent factors which predicted a final distance logMAR visual acuity of 1.3 (20/400) or any arbitrary definition of blindness.

CONCLUSIONS

The study showed that it was possible to select cases that were more likely to experience an improvement in vision following MRS.

Multifixation campimetry on line: a perimeter for the detection of visual field loss using the internet

More widespread perimetry would improve opportunities for preventing visual handicap from ocular and intracranial diseases, some of which are life threatening. With internet access becoming more ubiquitous, the authors have developed multifixation campimetry on line, for qualified practitioners and lay individuals around the world, free of charge.

Trypan blue staining of internal limiting membrane and epiretinal membrane during vitrectomy: visual results and histopathological findings

AIMS

To report on the use of trypan blue (TB) 0.06% for staining the internal limiting membrane (ILM) and epiretinal membrane (ERM) during vitrectomy and report on their histology.

METHOD

14 consecutive patients with idiopathic macular hole or macular pucker (seven patients each) were prospectively recruited for ILM or ERM peel respectively. After pars plana vitrectomy and induction of posterior vitreous detachment, 0.5 ml TB 0.06% in phosphate buffered saline (VisonBlue) was injected over the posterior pole in an air filled eye and left for 2 minutes. The stained tissue was peeled with intraocular forceps. Specimens were evaluated using histochemical and immunohistochemical methods.

RESULTS

The average follow up was 4.4 months. Internal limiting membranes and epiretinal membranes were stained satisfactorily in all cases and removed successfully. Eight patients (57%) had improvement of 2 or more Snellen lines. All seven macular holes closed. In the ERM cases, no residual membranes were observed clinically, at the latest follow up. No complications relating to the use of the dye were encountered intraoperatively or postoperatively. Of the 14 procedures, nine (four macular hole and five macular pucker) yielded sufficient tissue for histopathological evaluation. Histological and immunohistological assessment revealed that the morphology of these specimens was similar to that observed in macular hole ILM and macular pucker ERM removed without the aid of dye.

CONCLUSION

TB staining facilitated the identification and delineation of ILM and ERM removal during the surgical management of macular holes and macular pucker. The visual outcome of this series and the specimens removed suggest they are no different from those without TB staining. Its use in posterior segment appears to be safe but further studies are required to investigate its long term safety.

Vitreous penetration of levofloxacin in the uninflamed phakic human eye

AIMS

To assess the vitreous penetration of oral levofloxacin (a new fluoroquinolone antibiotic with improved Gram positive activity) in uninflamed phakic eyes.

METHODS

15 patients for macula hole surgery were recruited to the study. 10 received a single 500 mg dose of levofloxacin by mouth preoperatively. Five acted as controls. Serum and undiluted vitreous samples were obtained at surgery and analysed by HPLC.

RESULTS

Levofloxacin was detectable 2.5 hours after administration in the vitreous. A peak concentration of 1.6 microg/ml (or mg/l) was measured between 2.5 and 4 hours post-dose.

CONCLUSION

Oral levofloxacin reaches the vitreous rapidly in the uninflamed phakic eye. Levels did not reach MIC(90) for the commonest infecting organisms. Nevertheless, levofloxacin would be expected to be active against a higher proportion of infecting organisms than either ciprofloxacin or ofloxacin.

Determinants of visual outcome after pars plana vitrectomy for posteriorly dislocated lens fragments in phacoemulsification

PURPOSE

To evaluate the visual outcome of patients with posteriorly dislocated lens fragments after phacoemulsification managed with pars plana vitrectomy (PPV) and identify risk factors for poor visual outcome.

SETTING

Vitreo-Retinal Service, St. Paul Eye Unit, Liverpool, United Kingdom.

METHODS

The medical records of all patients who had PPV for posteriorly dislocated lens fragments after phacoemulsification between March 1993 and August 1998 were retrospectively reviewed. Demographics, preexisting eye conditions, details of the previous cataract surgery, findings at presentation, details of the vitreoretinal procedure, final visual acuity, and complications observed during the follow-up were evaluated. Univariate and multiple regression analyses were used to determine the significance of these clinical variables as determinants of poor visual outcome (visual acuity 6/12 or worse).

RESULTS

Of the 106 patients identified, 89 had a full set of data and were included in the study. In 79 patients (89%), PPV was performed from 1 to 357 days (median 15 days) after cataract extraction. In 10 patients (11%), PPV was done on the same day as the cataract surgery. Sixty-two patients (69%) had a final visual acuity of 6/12 or better. Preexisting eye disease (P <.01), PPV delayed for more than 4 weeks (P <.03), occurrence of retinal detachment after vitrectomy (P <.01), and the use of ultrasound (US) fragmentation (P <.01) were statistically significantly correlated with a poor visual outcome.

CONCLUSIONS

Posterior dislocated lens fragments after phacoemulsification were safely retrieved using PPV. It appears that intervening early (within 4 weeks) and avoiding the use of US fragmentation are associated with a better visual outcome and reduced rate of postoperative complications.

New surgical approach in the management of pseudophakic malignant glaucoma

PURPOSE

To describe a new surgical approach in the management of pseudophakic malignant glaucoma.

DESIGN

Noncomparative case series.

PARTICIPANTS

Five consecutive patients with pseudophakic malignant glaucoma.

METHODS

All patients underwent zonulo-hyaloido-vitrectomy. The procedure involves the performance of zonulectomy, hyaloidectomy, and anterior vitrectomy (zonulo-hyaloido-vitrectomy) through a peripheral iridectomy or iridotomy via the anterior chamber.

MAIN OUTCOME MEASURES

Medications, visual acuity, intraocular pressure, and anterior and posterior segment findings were recorded before and after surgery.

RESULTS

Resolution of the malignant glaucoma was achieved in all cases. No recurrences were observed after a median follow-up of 5.5 months (range, 1-9 months). In one patient with extensive anterior synechiae, bleb failure occurred after the resolution of the malignant glaucoma. This patient was treated successfully with a guarded filtration procedure supplemented with 5-fluorouracil. No other complications were observed.

CONCLUSIONS

Zonulo-hyaloido-vitrectomy via the anterior segment appears to be an alternative option in the treatment of patients with pseudophakic malignant glaucoma.

Modulation of retinal pigment epithelial cell behavior by Agaricus bisporus lectin

PURPOSE

To determine whether Agaricus bisporus lectin (ABL) binds retinal pigment epithelial cells (RPEs), to conduct a preliminary viability study of RPEs exposed to ABL, and to evaluate the effects of ABL on RPE proliferation and RPE-mediated matrix contraction in vitro.

METHODS

Using cultured bovine RPEs, immunohistochemistry was used to study ABL binding. Morphologic and trypan blue exclusion techniques were used for toxicity studies. The effect of ABL on RPE proliferation was investigated by [methyl-3H]-thymidine incorporation. The effect of ABL on RPE-mediated matrix contraction was evaluated with RPE-populated three-dimensional collagen matrices.

RESULTS

ABL bound to RPE cells. This binding was inhibited by asialomucin. No change in RPE morphology or trypan blue exclusion compared with controls was observed in RPEs incubated with 5 to 60 microg/ml ABL for 3 days. Twenty-four-hour incubations of RPEs with ABL significantly inhibited RPE proliferation in a dose-dependent way, 40 microg/ml ABL inhibited proliferation by 83% (SE 14, P<0.05). ABL showed a dose-dependent significant inhibition of RPE-mediated collagen matrix contraction over 3 days, with 93% inhibition compared with controls by 40 microg/ml lectin (P<0.05). The inhibitory effect of ABL on proliferation and gel contraction was partly reversible after eliminating ABL from the culture medium.

CONCLUSIONS

Bovine RPE cells bind ABL, and preliminary evaluations suggest that levels of ABL that are nontoxic to the cells potently inhibit RPE proliferation and RPE-mediated matrix contraction. ABL deserves further investigation as a potential inhibitor of RPE proliferation and cell-mediated matrix contraction in anomalous reparative processes such as proliferative vitreoretinopathy and as a laboratory tool for RPE behavioral studies.

Visual function and patient satisfaction after macular hole surgery

PURPOSE

Over recent years success in macular hole surgery has increased in terms of anatomical closure. However, debate still continues on the benefit to the patient in terms of visual outcome. We designed a prospective study to investigate the outcome of full thickness macular hole (FTMH) surgery in terms of anatomical closure, visual outcome, incidence of complications and patient satisfaction.

METHODS

Thirty eyes of 30 consecutive patients with FTMH were prospectively studied (stage 2 = 2; stage 3 = 23; stage 4 = 5). All cases had surgery involving vitrectomy, injection of an autologous platelet aggregate over the hole and gas tamponade. At 3 months post-operatively all cases were assessed for closure of the FTMH, Snellen acuity and the incidence of complications. At this stage all patients completed a patient satisfaction questionnaire.

RESULTS

Anatomical closure of the hole was achieved in 83% of cases (25/30). Visual improvement of 2 Snellen lines or more occurred in 50% of cases (15/30). A vision of 6/12 or better was achieved in 27% of cases (8/30). A post-operative lens opacity was present in 46% (13/28) of phakic patients and a temporal, peripheral wedge-shaped field defect occurred in 17% (5/30) of cases. In this study, 53%, 70%, 57% and 67% of patients gave a positive response to specific questions about satisfaction with near, intermediate and distance vision and overall visual function respectively.

CONCLUSIONS

Although the anatomical success of FTMH surgery is high the functional outcome in terms of Snellen acuity is less rewarding. Analysis of patient satisfaction suggests that the arbitrary visual outcome measures presently used may underestimate the functional benefit to the patient. Improved objective measures of visual outcome are required to assess the benefit of surgery in these cases.

Local anaesthesia for vitreoretinal surgery: a case-control study of 200 cases

PURPOSE

In the United Kingdom the majority of vitreoretinal (VR) surgery is performed under general anaesthesia (GA). The aim of this study was to demonstrate the scope of local anaesthesia (LA) for VR surgery, to measure the acceptance of LA to patients and surgeons and to compare the surgical outcomes, complication rates and duration of the surgical procedures under LA and GA.

METHODS

A case-control study was undertaken to compare 100 cases performed under LA with 100 matched cases performed under GA. The matching of cases was based on multiple criteria such as configuration and complexity of retinal detachment, the involvement of the macula, the number and site of retinal tears, presence and severity of proliferative vitreoretinopathy, experience of the surgeon and the type of the surgical procedure. A clinical audit was also carried out on 65 successive patients using a questionnaire to determine the acceptability of LA to patients and surgeons.

RESULTS

Anatomical and visual success rates, and intra-operative and post-operative complications, were similar in cases carried out under LA and GA. The mean duration of the surgery (excluding anaesthetic time) was significantly shorter for LA than GA procedures (p < 0.001). The acceptance for LA was high for both patients and the operating surgeons.

CONCLUSIONS

We found that VR surgery can be safely and efficiently performed under LA. Adoption of LA has increased our throughput.

Endoresection of choroidal melanoma

AIMS

The results of 52 endoresections for choroidal melanoma are reported.

METHODS

The current technique involves vitrectomy, retinal incision over or peripheral to the tumour, haemostasis by raising intraocular pressure and by moderate hypotensive anaesthesia, choroidal incision around tumour, endoresection with vitrector, endodiathermy to bleeding points and residual tumour, fluid-air exchange to reattach retina, endolaser to achieve retinal adhesion around the coloboma and destroy residual tumour in the sclera, silicone oil injection with removal after 12 weeks, cryotherapy to the sclerotomies, and adjunctive ruthenium plaque radiotherapy in selected cases.

RESULTS

Patients receiving primary endoresection had a mean age of 53 years, a mean largest basal tumour diameter of 8.2 mm, and a mean tumour thickness of 3.9 mm. 40 tumours extended to within 2 disc diameters of the optic disc, with 17 involving disc. Follow up ranged from 40 days to 7 years (median 20 months). At the last visit, 90% of eyes were retained, with vision of 6/6-6/12 (two), 6/18-6/36 (three), 6/60 to counting fingers (18), hand movements (nine), and light perception (four). The main complications were retinal detachment in 16 and cataract in 25. Secondary endoresection (11) was performed after plaque radiotherapy (four), photocoagulation (four), trans-scleral local resection (two), and proton beam radiotherapy (one), with retention of the eye in nine cases. By the close of the study, no patients developed definite local tumour recurrence but one died of metastatic disease 41 months postoperatively.

CONCLUSION

Depending on tumour location, endoresection may conserve central vision or temporal field when radiotherapy would be expected to cause optic neuropathy. Longer follow up is necessary to establish the efficacy of tumour control.

Does cryotherapy before drainage increase the risk of intraocular haemorrhage and affect outcome? A prospective, randomised, controlled study using a needle drainage technique and sustained ocular compression

AIMS/BACKGROUND

A prospective, randomised, controlled clinical trial was conducted to investigate the effect of performing cryotherapy before drainage of subretinal fluid (SRF) on the incidence of intraocular haemorrhage (IOH) in the management of retinal detachment.

METHODS

Eighty eyes of 80 patients with rhegmatogenous retinal detachment requiring SRF drainage were recruited. Thirty four cases were randomised to receive drainage before cryotherapy (drainage, air injection, cryotherapy, and explant = DACE group) while 46 cases had drainage after cryotherapy (cryotherapy, drainage, air injection, and explant = CDAE group). All cases had trans-scleral drainage of SRF using a 27 gauge hypodermic needle combined with prolonged, intraocular hypertension.

RESULTS

There was a low incidence of IOH associated with drainage in both groups with no statistically significant difference between the groups (DACE group = 2.9%; CDAE group = 4.3%; p = 0.43). There was no significant difference between the groups in the rate of anatomical success with a single operation (DACE group = 82.4%; CDAE group = 86.9%; p = 0.38). There was no significant difference between the groups in the visual outcome. An improvement of two Snellen lines or more occurred in 52.9% of the DACE group and in 56.5% of the CDAE group (p = 0.93).

CONCLUSION

It was concluded that the surgical sequence of applying cryotherapy before drainage of SRF can be safely and effectively performed. The sequences CDAE and CDE, when air injection is not required, along with DACE should all be part of the surgical repertoire for the management of retinal detachments.

The effect of anaesthesia on the intraocular volume of the C3F8 gas bubble

Long-acting intraocular gas bubbles are frequently used during vitrectomy to tamponade retinal breaks. The aim of this study was to determine the effect of nitrous oxide anaesthesia on the size and effectiveness of the post-vitrectomy gas bubble. Twenty vitrectomy procedures with injection of 12% perfluoropropane (C3F8) gas were performed. For 10 of the cases routine anaesthesia with nitrous oxide was used and for 10 cases non-nitrous anaesthesia with propofol was used. The volume of the intraocular gas bubble was estimated 24 hours post-operatively using A-scan biometry. At 24 hours the gas bubble occupied a mean of 65.1% of the eye in anaesthesia with nitrous oxide and a mean of 66.1% in anaesthesia with intravenous propofol. The wide range of values of gas-fill recorded at 24 hours makes comparison of the two groups inappropriate. Several factors may account for this spread of values, but in our opinion it is the uncontrolled leakage from the sclerostomies which is the most likely. This study suggests that anaesthesia using nitrous oxide does not adversely affect the size of the C3F8 gas bubble at 24 hours post-vitrectomy when compared with anaesthesia without nitrous oxide.

The effect of alpha-amylase on the acrosomal membrane of human sperm

PURPOSE

Sperm capacitation and the acrosome reaction are prerequisites to accomplishing fertilization. The object of this research was to induce capacitation and the acrosome reaction of human sperm, comparing the acrosome status of fertile and infertile men, using alpha-amylase.

METHODS

Acrosome status was measured using indirect immunofluorescence (IIF; monoclonal antibody GB24, Thèramex), hemizona assay (HZA), and transmission electron microscopy (TEM).

RESULTS

Acrosome-reacted sperm without alpha-amylase treatment was significantly more abundant in the fertile versus the infertile group utilizing IIF, HZA, and TEM. alpha-Amylase-treated spermatozoa from the fertile and infertile groups showed a significant increase in the number of sperm bound to the hemizona (P < 0.05).

CONCLUSIONS

The percentage of acrosome-reacted sperm in the infertile group was significantly enhanced by alpha-amylase, utilizing IIF and TEM.

Micromanipulation at an infertility centre

AIM

Human in vitro fertilisation (IVF) and gamete intrafallopian transfer have been used in the management of various forms of infertility. In cases of severe male-factor infertility, fertilisation can be a factor. In this study micromanipulation was used to increase fertilisation in such cases.

METHODS

Two micromanipulation techniques, subzonal sperm injection (SUZI) and partial zona dissection (PZD), were used to assist fertilisation in patients with abnormal semen parameters. Ten couples with severe oligo-, terato- and asthenozoospermia participated in the SUZI programme. Seventy-three oocytes were obtained from these 10 patients. PZD was used on day 1 oocytes in cases of male infertility as well as a rescue attempt on day 2 oocytes when fertilisation had failed after routine insemination.

RESULTS

The SUZI technique had a fertilisation rate of 37.7%. In this group, a biochemical pregnancy was achieved. Differences between the fertilisation rate of conventional IVF (33.3%) and PZD (56.3%) in cases of male infertility, were not statistically significant although a clinical difference could be detected. PZD was statistically effective in facilitating fertilisation (37.5% v. 8.3%) in couples where this procedure was introduced to reinseminate 24-hour-old unfertilised oocytes. Four patients received PZD reinseminated embryos. An average of 1.45 PZD embryos were replaced and 1 implantation pregnancy was confirmed.

CONCLUSION

The micromanipulation results are encouraging and seemed to increase the efficiency of IVF in humans. Furthermore, our data support the conclusion that micromanipulation procedures can bring about pregnancies.