Displaced intraocular lens repositioning using a reversed 10-0 straight polypropylene needle lasso technique.
Explore the source record for details and available documents.
Humans↗
Biomedical subjects
J D Stevens
Publications and source records attributed to J D Stevens.
Curved, sub-tenon cannula for local anesthesia.
I describe a new cannula for delivery of sub-Tenon's local anesthetic solution. The cannula has a rigid structure, a 19-gauge diameter, and a shaft with a gentle curve, specifically designed to follow the contour of the globe. Anteroposterior flattening of the tip facilitates advancement of the cannula within the potential Tenon's-space tissue plane. Without the acute angulation of the shaft of the Bishop-Harmon-style cannula, it is easier to follow the globe contour and create less tenting-up of conjunctiva.
Anesthesia, Local↗
Mathematical modelling of the elastic properties of retina: a determination of Young's modulus.
The retina can be regarded as an elastic membrane or sheet which stretches and deforms when a force is applied to it. Isolated bovine retina was taken and a graded traction force applied to determine retinal profile as a function of force. The resulting profile can be modelled mathematically and the model then used to determine a value for the elastic constant. The value of the elastic constant obtained by this method is approximately 2 N/m. This value of the elastic constant, combined with the observed retinal thickness, yields a value of Young's modulus for retina of approximately 2 x 10(4) Pa, which is about 2 orders of magnitude weaker than typical rubber. This value can then be used in modelling retinal behaviour in vivo when forces are applied to detached retina.
Animals↗
Four-quadrant local anaesthesia technique for vitreoretinal surgery.
We report our experience of a recently described local anaesthetic technique which seeks to avoid risk of perforation of the globe, damage to the optic nerve, or injection into the subarachnoid space, whilst providing prolonged and reliable anaesthesia. A prospective series of 19 patients who underwent vitreoretinal surgery using this technique were compared with 19 patients who had retrobulbar anaesthesia for cataract extraction. The vitreoretinal group had excellent akinesia and very good anaesthesia, allowing prolonged retinal reattachment surgery lasting up to 3 hours. Patient evaluation of discomfort or pain experienced in the two groups was assessed using a visual analogue pain score chart. The pain scores for the two groups were not significantly different (p = 0.03) and 16 of 19 patients in each group (84%) experienced only slight pain or less. Satisfaction with local anaesthesia, in both groups, was also assessed by asking patients which method of anaesthesia they would prefer if future surgery were to be performed. In the vitreoretinal group, 18 of 19 patients expressed a preference for local anaesthesia and in the cataract group 17 ot 19 also favoured local anaesthesia. The vitreoretinal patients' median pain score was 0 compared with 1 for the cataract patients. This study demonstrates that local anaesthesia provides pain relief for vitreoretinal surgery which is comparable to the experience of patients undergoing cataract surgery by retrobulbar anaesthesia. The technique described can provide successful local anaesthesia for vitreoretinal procedures. The success of this technique for pain relief and akinesia calls for a reappraisal of the number of patients suitable for vitreoretinal surgery under local anaesthesia.
Anesthesia, Local↗
Mathematical modelling of retinal tear formation: implications for the use of heavy liquids.
When force is applied to detached retina it elevates, stretches, and becomes irreversibly deformed. Finally it tears, and the timing and location of tear formation are determined by the distribution of stress within the retina. This stress distribution is dependent upon the retinal contour. We have tested this using retinas of freshly enucleated bovine eyes. A suture was attached to isolated retinal tissue using butylacrylate (Histoacryl) glue and traction was applied to this suture so stretching the retina. We present a mathematical model of the in vitro data obtained, with predictions for local retinal internal tensions. We show that these are altered by the addition of hydrostatic forces due to the presence of heavy liquids. These findings have implications for epiretinal membrane dissection during surgery and for the use of heavy liquids during membrane peeling.
Animals↗
Plasminogen activator in human tears.
Measurements were made of the nature and levels of plasminogen activator in human tears using, as a model of inflammation, patients undergoing cataract surgery. Tissue plasminogen activator (t-PA) but not urokinase plasminogen activator (u-PA) was found in tears. A wide variation in the range of t-PA in pre-operative tears was found. In those patients not receiving per-operative subconjunctival betamethasone a significant rise in t-PA was found in tears on the first post-operative day over pre-operative levels. A significant fall was noted in those receiving per-operative subconjunctival betamethasone.
Betamethasone↗
Survey of the contamination of eyedrops of hospital inpatients and recommendations for the changing of current practice in eyedrop dispensing.
Topical ophthalmic medications used on the ward and from the outpatient area have been taken and cultured for potential bacterial contamination in the laboratory. We examined 143 bottles used by patients who had had routine cataract surgery and trabeculectomy. We also examined for bacterial contamination 216 bottles of eyedrops used in the outpatient area of the hospital. No contamination was found in the postoperative eyedrops, but five bottles were contaminated from the outpatient area (2.3%). The bacterial growth from outpatient drops was of the same order of magnitude as in previous studies. The practice in the UK for postoperative eyedrops to be discarded and fresh, separate bottles to take home is discussed. We recommend that this practice be changed so that the postoperative drops used for 72 hours or less are taken home.
Cataract Extraction↗
A new local anesthesia technique for cataract extraction by one quadrant sub-Tenon's infiltration.
A new technique of local anesthetic administration has been used for 50 patients undergoing cataract extraction. The simple technique involves direct transconjunctival infiltration of local anaesthetic directly to the sub-Tenon's space, in the inferior-nasal quadrant, using a blunt 19-gauge Southampton cannula. This method seeks to avoid the risks of retrobulbar haemorrhage, perforation of the globe, damage to the optic nerve, and injection into the subarachnoid space, whilst providing prolonged and reliable anaesthesia. Akinesia is achieved by the inferior-nasal placement of solution and if not sufficient, a top-up can easily be given. Patients graded any discomfort or pain using a 10 cm visual analogue graphical pain score chart with numerical and descriptive rating scale. The delivery of 50:50 mixture of lignocaine 2% and bupivacaine 0.5% anaesthetic was evaluated by patients with a median response of 'slight discomfort'. The operative procedure was graded with a median of 'no pain or discomfort', both for extracapsular cataract extraction and phakoemulsification. This is a new, modified, sub-Tenon technique which is simple, reliable, and which offers excellent anaesthesia and akinesia and avoids a sharp instrument being passed into the orbit.
Anesthesia, Local↗
Double-blind comparison of epidural diamorphine and intramuscular morphine after elective caesarean section, with computerised analysis of continuous pulse oximetry.
A randomised, double-blind comparison of the efficacy, duration of action and side effects of two analgesic regimens following elective epidural Caesarean section is described. Patients received epidural diamorphine 3 mg or intramuscular morphine 10 mg in the immediate postoperative period. Time to next analgesia was longer after epidural diamorphine (11.0 hours) compared to intramuscular morphine (6.5 hours) (p less than 0.05). In addition, a greater number of patients in the diamorphine group had a pain score less than 2.5 cm at 5 hours (p less than 0.05). However, more patients in the diamorphine group required catheterisation and suffered emetic sequelae, whereas more patients in the morphine group were sedated at 8 hours. Ten patients in each group had continuous pulse oximetry performed overnight after administration of the trial medications. Neither group demonstrated evidence of hypoxia.
Analgesia, Epidural↗
Evaluation of the Graseby PCAS. A clinical and laboratory study.
The Graseby patient-controlled analgesia system was evaluated in the laboratory and in clinical use. The problems encountered with eight examples used to treat 510 patients are reported. Laboratory performance revealed the unit to be accurate at infusion volumes of 1 and 2 ml.
Analgesia, Patient-Controlled↗
Oestrus ovis ophthalmomyiasis acquired in the UK: case report and scanning electron microscopic study.
A case of external ophthalmomyiasis acquired in the UK is reported. Oestrus ovis infestation of the external conjunctiva is described and a scanning electron microscopic study made of the first stage larvae. To our knowledge this represents only the third case reported of UK acquisition of ophthalmomyiasis.
Adult↗
Dystrophia myotonica--emergency caesarean section with spinal anaesthesia.
Explore the source record for details and available documents.
Adult↗
Stress birefringence in the human cornea.
Stress-induced birefringence is used in engineering to determine the distribution of mechanical stress in experimental models. The phenomenon has previously been reported in the cat cornea but no data for the human exists. A qualitative description of stress-induced birefringence in the human cornea in vitro is presented. Circularly polarised light is then used to detect the phenomenon in the post-operative human cornea in vivo.
Birefringence↗
Fatal haemopathological consequences of general anaesthesia.
A previously healthy 63-yr-old female died following an anaphylactoid response to anaesthesia with thiopentone and suxamethonium. Postmortem findings strongly suggested that disseminated intravascular coagulation played a significant role in her death. The local mechanism behind the reaction is unknown, but the formation of thiopentone-suxamethonium colloid aggregates during induction, may have led to "aggregate anaphylaxis".
Anaphylaxis↗
Ophthalmic use of chloramphenicol.
Explore the source record for details and available documents.
Administration, Topical↗
Anaphylactoid reactions to prilocaine.
Explore the source record for details and available documents.
Aged↗