Sub-Tenon's local anaesthesia for the treatment of retinopathy of prematurity with diode laser

PURPOSE

To evaluate the safety and efficacy of sub-Tenon's local anaesthesia (LA) for laser treatment of threshold retinopathy of prematurity (ROP).

METHODS

A cohort of 18 eyes of 10 neonates with threshold ROP was treated with diode laser peripheral retinal ablation over 14 treatment sessions using oral sedation and sub-Tenon's anaesthesia. Treatment was performed in a neonatal unit. The heart and respiratory rate, trans-cutaneous oxygen saturation, and physical activity were continuously monitored for signs of neonatal distress. Cardio-respiratory stability during and after the procedure was scored for each eye treated using a Cardio-respiratory index described previously.

RESULTS

In all cases, the planned dose of laser was delivered. One out of 18 eyes developed stage 4b tractional retinal detachment over a follow-up of at least 6 months for all babies. Systemic complications during treatment included transient bradycardia and apnoea requiring stimulation in two babies and excessive head mobility in three babies. Treatment duration varied between 20 and 80 min. Ocular complications were conjunctival haemorrhage and chemosis. The mean cardio-respiratory index was 1.13, which compared favourably with the standard published.

CONCLUSIONS

Sub-Tenon's LA with oral sedation appears to be a safe and effective alternative to general anaesthesia for laser treatment of ROP, with the potential for lower morbidity.

Variation in anaesthesia for the laser treatment of retinopathy of prematurity—a survey of ophthalmologists in the UK

PURPOSE

Laser treatment for retinopathy of prematurity (ROP) may be associated with systemic stress for the infant. No national consensus on the optimum method of anaesthesia for the treatment of ROP currently exists. This study ascertains the anaesthetic practices employed for the treatment of ROP by ophthalmologists in the United Kingdom (UK), and also their attitudes towards these practices.

MATERIALS AND METHODS

A postal questionnaire was sent to 46 consultant ophthalmologists identified as performing treatment for ROP in the UK. The consultants were asked to estimate the annual number of babies with ROP that they treated with laser, what methods of anaesthesia they employed, for comments regarding the arrangements for, and types of anaesthesia employed and whether they believed that the neonatal stress response to laser treatment was associated with a significant risk of systemic complications.

RESULTS

In all, 35 (76%) questionnaires were returned. A total of 30 (86%) respondents reported performing laser treatment for ROP. Of these, 15 (50%) used general anaesthesia for all cases and 11 (37%) intravenous sedation combined with topical anaesthesia for all cases. Oral sedation combined with topical anaesthesia, rectal chloral hydrate and paracetamol combined with topical anaesthesia, intravenous ketamine combined with topical anaesthesia, and subtenon's local anesthesia were used by one (3%) respondent each. There were no ophthalmologists using subconjunctival or topical anaesthetic alone or treating without anaesthesia.

CONCLUSION

This survey reveals considerable variation in practice among UK ophthalmologists regarding the anaesthetic methods employed in the treatment of ROP, and their beliefs regarding the systemic stress associated with treatment.

Intravitreal triamcinolone for the treatment of ischemic macular edema associated with branch retinal vein occlusion

PURPOSE

To evaluate the safety and efficacy of intravitreal triamcinolone acetonide (IVTA) for ischemic macular edema associated with branch retinal vein occlusion (BRVO) and foveal ischemia.

DESIGN

Prospective interventional case series.

METHODS

setting: Clinical practice. study population: Eighteen eyes of 18 patients with macular edema associated with BRVO and foveal ischemia. intervention: Four mg IVTA. main outcome measures: Visual acuity (VA), optical coherence tomography, macular thickness measurements, and treatment-related complications.

RESULTS

The mean duration of BRVO before treatment was 14 months. All patients were followed for a minimum of nine months, and 12 patients completed 12 months follow-up. The mean logarithm of the minimum angle of resolution (logMAR) VA improved significantly from 0.81 +/- 0.36 at baseline to 0.65 +/- 0.30 at one month (P = .03) but did not vary significantly from baseline at three, six, nine, and 12 months. Macular thickness improved significantly in all eyes from a mean of 400 +/- 134 mum preinjection, to 228 +/- 58 mum at one month (P < .01) and 256 +/- 121 mum at three months (P < .01) but did not vary significantly from baseline at six, nine, and 12 months. Eight eyes developed posterior subcapsular cataract, intraocular pressure (IOP) exceeded 21 mm Hg in four eyes, and two eyes developed vitreomacular traction during follow-up.

CONCLUSIONS

IVTA is effective in reducing ischemic macular edema associated with BRVO and foveal capillary nonperfusion. This reduction is often associated with a temporary improvement in VA. Raised IOP and development of posterior subcapsular cataract are disadvantages of this treatment.

Nutrition in burns: A practical solution to a difficult problem

The nutritional aspects of burns is an important but yet not properly looked after problem in the management of burns. We present our experience with dealing with such a problem giving a practical and easy to deliver solution to nutrition. Early enteral nutrition should be started with frequent assessment to the need of the patient and it requires a team approach.

Videoendoscope-Guided Fluorescein-Assisted Vitrectomy for Phakic Malignant Glaucoma

Malignant glaucoma is a rare secondary glaucoma classically occurring after intraocular surgery in eyes with primary angle closure. Pars plana vitrectomy is reserved for the treatment of malignant glaucoma when medical and laser treatment fail. The primary aim of surgery is the removal of the anterior vitreous to reduce resistance to aqueous flow into the anterior chamber. In phakic eyes, conventional pars plana vitrectomy without lens extraction is frequently unsuccessful because of difficulty visualizing the normally transparent anterior vitreous, combined with the technical challenge of removing the anterior vitreous without damaging the crystalline lens. We describe a technique of intraocular, videoendoscope-guided, fluorescein-assisted pars plana vitrectomy that enables direct visualization and thorough removal of the anterior vitreous without the need for lens extraction in prepresbyopic patients without cataract.

Serial autofluorescence imaging over two years following indocyanine green-assisted internal limiting membrane peel for macular hole

A 65-year-old patient with an idiopathic full-thickness macular hole underwent a vitrectomy, inner limiting membrane (ILM) peel and gas tamponade. The ILM was stained using 0.5% indocyanine green (ICG). Postoperative autofluorescence imaging shows a central focal hyperfluorescence surrounded by a perifoveal hypofluoresecnt area corresponding to the dyed and peeled ILM. Serial autofluorescence images showed progressive decrease in staining until 2 years later when no signs of ICG autofluorescence were apparent. The visual acuity for this patient improved two Snellen lines from 6/36 to 6/18 at 2 years. ICG may not be clinically toxic as is currently feared.

Design, synthesis and pharmacological evaluation of some novel 2-(4-nitrophenyl)-3-methylthio-3-(substituted)arylamino acrylamides as potential anti-inflammatory agents

On the basis of structure based drug design we have designed a series of 2-(4-nitrophenyl)-3-methylthio-3-(substituted)arylamino acrylamides as potential antiinflammatory agents. Good 3D similarity was observed between the designed molecule and rofecoxib (r.m.s.d. 0.161). The effect of opening the central ring and introducing a spacer (-NH-) between one of the aryl rings and the central ring of the basic structure of the COX-2 inhibitors was also studied. The designed molecules were synthesised by thiocarbomylation of the 4-nitro-phenylacetamide with aryl isothiocyanates followed by subsequent methylation of the enethiolate salts. All compounds were screened for their antiinflammatory activity by the carrageenan induced rat paw edema method. Compounds 4 and 6 exhibited potent antiinflammatory activity, which was found to be comparable with the standard drug, rofecoxib. Both the potent molecules were also screened for their ulcerogenic potential in Albino rats. A very low ulcer index was observed with both compounds, although higher than rofecoxib.

Optical coherence tomography under general anesthesia in a child with nystagmus

PURPOSE

To describe a method that permits optical coherence tomography scanning to be performed under general anesthesia.

DESIGN

Observational case report.

METHODS

A 7-year-old child underwent optical coherence tomography scanning under general anesthesia. He was positioned prone, with the neck extended to enable vertical facial alignment on the scanner. An anti-Trendelenburg trend on the operating table minimized the degree of neck extension required. Intravenous fluids, modest ventilator airway pressures, and compression stockings were used to minimize perioperative hemodynamic disturbance and the potential for orthostatic hypotension associated with the anti-Trendelenburg trend.

RESULTS

High-quality, diagnostically important optical coherence tomography scans were obtained.

CONCLUSION

With appropriate patient positioning and anesthetic management, optical coherence tomography scanning can be performed on uncooperative adults and children under general anesthesia.

Inhibition of estrone sulfatase (ES) by alkyl and cycloalkyl ester derivatives of 4-[(aminosulfonyl)oxy] benzoic acid

In our search for potent inhibitors of the enzyme estrone sulfatase (ES), we have undertaken the synthesis and biochemical evaluation of a range of esters of 4-[(aminosulfonyl)oxy] benzoic acid. The results of the study show that the synthesised compounds possess potent inhibitory activity, indeed the cyclooctyl derivative was found to be more potent than 667-COUMATE, which is currently undergoing clinical trials.

Outcome of ICG-assisted ILM peel in macular hole surgery

PURPOSE

To investigate whether indocyanine green (ICG) staining of the internal limiting membrane (ILM) improves surgical outcome.

METHODS

A total of 34 patients were identified who underwent macular hole surgery with ILM peeling augmented with ICG. These were matched retrospectively with 34 patients who underwent macular hole surgery without the use of ICG. Closure rates from primary and secondary procedures were compared, as were changes in Snellen and Logmar visual acuity.

RESULTS

There was no significant difference between the two groups with reference to demographic features of age, sex, staging of the macular holes, and the proportion subsequently undergoing cataract surgery. The mean follow-up period was 7.7 months in the ICG group and 6.3 months in the non-ICG group. Closure rates from primary surgery were 91.2% in the ICG group and 73.5% in the non-ICG group (P = 0.056), whereas overall closure rates following further surgery were similar in both groups (94.1 and 91.2%, respectively). Logmar visual improvement above baseline was achieved in 53% of the non-ICG group compared to 82% of the ICG group (P = 0.01). Where primary hole closure occurred, there was no statistically significant difference in visual outcome between the two groups.

CONCLUSION

ICG-assisted ILM peel in macular hole surgery is associated with a higher closure rate following a single surgical procedure. This difference was found to approach statistical significance (P = 0.056). Overall visual improvement was greater in the ICG group (P = 0.01); however, this reflected the higher closure rates. Visual outcomes between the two groups were comparable where primary hole closure occurred.

The design, synthesis, and in vitro biochemical evaluation of a series of esters of 4-[(aminosulfonyl)oxy]benzoate as novel and highly potent inhibitors of estrone sulfatase

We report the initial results of our study into the use of a potential transition-state (TS) of the reaction catalysed by the enzyme estrone sulfatase (ES) in the design of a series of cyclic esters of 4-[(aminosulfonyl)oxy]benzoate as novel inhibitors of ES. The results of the study show that these compounds are some of the most potent inhibitors known todate, possessing greater inhibitory activity than the three standard compounds: 4-methylcoumarin-7-O-sulfamate (COUMATE); the tricyclic derivative of COUMATE, namely 667-COUMATE (which is in Phase I of clinical trials) and; the steroidal inhibitor estrone-3-O-sulfamate (EMATE).

Structure-activity relationship determination within a group of substituted phenyl sulfamate based compounds against the enzyme oestrone sulfatase

The enzyme oestrone sulfatase (ES) is responsible for the conversion of the stored (sulfated) form of oestrogens to the active form, namely oestrone. In our continuing quest to synthesize potent inhibitors of oestrone sulfatase and to determine the structural requirements for such inhibition, we have synthesized and evaluated several derivatives of phenyl sulfamate. We report the results of the synthesis and biochemical evaluation of a series of 3- and 4-aminosulfonated derivatives of phenol in an effort to investigate the role of the acid dissociation constant (pK(a)), and therefore the stability of the phenoxide ion, on the inhibitory activity of compounds against this enzyme. The results showed that there was a strong correlation between the observed pK(a) and inhibitory activity within the aminosulfonated compounds considered. This suggested that in the inhibition of oestrone sulfatase by these compounds, pK(a) was an important physicochemical property, and as such, the stability of the O(-) ion was a crucial factor in the inhibition, and therefore the drug design process.

Design, synthesis and biochemical evaluation of AC ring mimics as novel inhibitors of the enzyme estrone sulfatase (ES)

We report the initial results of our study into a series of simple 4'-O-sulfamoyl-4-biphenyl based compounds as novel inhibitors of the enzyme estrone sulfatase (ES). The results of the study show that these compounds are potent inhibitors, possessing greater inhibitory activity than COUMATE, but weaker inhibitory activity than EMATE or the tricyclic derivative of COUMATE, namely 667-COUMATE. Furthermore, the compounds are observed to be irreversible inhibitors.