Validation of two scoring systems for the prediction of posterior capsule rupture during phacoemulsification surgery.

AIM: To attempt to validate two scoring systems for the prediction of intraoperative complication during phacoemulsification surgery. METHODS: The study population was patients attending Sunderland Eye Infirmary who underwent phacoemulsification surgery between 1 January 2001 and 31 December 2003. The authors applied each scoring system to a control group of 300 patients from this study population and extrapolated the results to give an estimate of the spread of scores for the entire population. They then applied the same scoring systems to all complicated cases from the same study population. Using these results they were able to calculate the risk of a complication for a particular score on each scoring system. CONCLUSION: The application of these systems in clinical practice would allow appropriate selection of phacoemulsification cases for trainee surgeons, more accurate consent from patients for their phacoemulsification surgery, and the unbiased comparison of surgical outcomes from surgeons with differing case mix difficulties.

Frisby Davis distance stereoacuity values in visually normal children.

AIMS: To establish the range of normal distance stereoacuity in young children using the Frisby Davis distance stereo test (FD2). METHODS: Children passing preschool vision screening assessments underwent measurement of distance stereoacuity with the FD2 using a standard testing protocol. RESULTS: 59 visually normal children aged between 36 months and 68 months were recruited to this study. All 59 were able to understand the test requirements and were examined with the FD2 stereo test. Four (6.8%) had no measurable stereoacuity; 13 (24%) had stereoacuity measurable only at a 3 metre testing distance (mean 92.3 seconds of arc; SD 52.6). These children were significantly younger than the remaining 42 (76%) who demonstrated a stereoacuity response at a 6 metre testing distance (mean 29.6 seconds of arc; SD 13.1, p=0.008). CONCLUSION: The FD2 stereo test enables the measurement of distance stereoacuity in young children. There appears to be a maturational effect with distance stereoacuity improving between 36 months and 68 months. The data on age related normal values will provide a baseline from which to compare outcomes in clinical populations.

Studies of DNA damage in rat pancreas and liver by 6-diazo-5-oxo-L-norleucine, ethyl diazoacetate and azaserine.

One hour following intraperitoneal injection of the pancreatic and liver carcinogen azaserine, 10 mg/kg (0.06 mmol/kg), DNA damage is present in both pancreas and liver of Wistar/Lewis rats as determined with alkaline sucrose gradients. Single injections (0.06 mmol/kg) of either of 2 structural analogues of azaserine, 6-diazo-5-oxo-L-norleucine (DON) and ethyl diazoacetate (EDA), do not damage pancreatic or liver DNA. EDA administered at 0.5 mmol/kg damages liver DNA, but not pancreatic DNA. Total radioactivity in pancreas and liver of Wistar rats 1 h after intravenous injection of [14C]azaserine, (10 microCi/kg), is 2.8 and 1.3 times respectively, the level of 14C-activity in pancreas and liver following injection [14C]EDA. Three to four times as much [14C]EDA localizes in the liver of Wistar rats as in the pancreas. Azaserine (0.06 mmol/kg weekly for 6 weeks) induces atypical acinar cell nodules (AACN) in pancreas of Wistar/Lewis rats. DON (0.06 mmol/kg weekly for 6 weeks) induces an elevated incidence, but low number of AACN in pancreas. EDA (0.10 mmol/kg weekly for 6 weeks) does not induce pancreatic AACN.

Methylprednisolone treatment in patients with brain tumors.

A study was made in 10 patients with brain tumors of the effect of methylprednisolone sodium succinate (Solu-Medrol) on clinical neurological status, intracranial pressure, and periventricular elastance. Significant clinical improvement and reduction in periventricular elastance both ocurred within 24 hours of starting treatment, whereas intracranaial pressure was not significantly reduced until the 2nd day of therapy.

Significance of intracranial hypertension in severe head injury.

Measurements of intracranial pressure (ICP) were begun within hours of injury in 160 patients with severe brain trauma, and continued in the intensive care unit. Some degree of increased ICP (greater than 10 mm Hg) was present on admission in most cases (82%), and in all but two of the 62 patients with intracranial mass lesions requiring surgical decompression; ICP was over 20 mm Hg on admission in 44% of cases, and over 40 mm Hg in 10%. In patients with mass lesions only very high ICP (greater than 40 mm Hg) on admission was significantly associated with a poor neurological picture and outcome from injury, while in patients with diffuse brain injury any increase in ICP above 10 mm Hg was associated with a poorer neurological status and a worse outcome. Despite intensive measures aimed at prevention of intracranial hypertension, ICP rose over 20 mm Hg during the monitoring period in 64 of the 160 patients (40%). Postoperative increases in ICP over 20 mm Hg (mean) were seen in 52% of the patients who had had intracranial masses evacuated, and could not be controlled by therapy in half of these cases. Even in patients without mass lesions, ICP rose above 20 mm Hg in a third of the cases, despite artificial ventilation and steroid therapy. Of the 48 patients who died, severe intracranial hypertension was the primary cause of death in nearly half and even moderately increased ICP (greater than 20 mm Hg) was associated with higher morbidity in patients with mass lesions and those with diffuse brain injury. Measurement of ICP should be included in management of patients with severe head injury.

Alloxan analogues as potential pancreatic-imaging radiopharmaceuticals.

Three families of alloxan derivatives, 5-arylthiobarbituric, 5-aryliminobarbituric, and 5-aryldialuric acids, were prepared as prospective radioiodine-transporting radiopharmaceuticals for the delineation of pancreatic insulinomas. Members of each class were screened for effects on blood sugar levels in a rat glucose tolerance assay. Transient hyperglycemia was observed with 5-(2,4-dichlorophenyl)iminobarbituric acid. No agent evaluated induced permanent diabetes at the doses tested.

Population Dynamics of Plant Nematodes in Cultivated Soil: Effect of Sod-based Rotations in Cecil Sandy Loam.

In a 6-year study of four nematode species in sod-based corn (Zea mays) rotations, population densities varied with different cropping systems. Continuous corn, with or without a winter rye (Secale cereale) or vetch (Vicia villosa) cover, favored an increase of Pratylenchus zeae and suppressed Trichodorus christiei, Helicotylenchus dihystera, and Xiphinema americanum. A four-year sod-based rotation (3 years sod, 1 year corn) of 'Coastal' bermudagrass (Cynodon dactylon) and fescue (Festuca arundinacea) was less favorable for P. zeae than was monocultured corn but was more favorable for T. christiei. Alfalfa (Medicago sativum) and rescue favored an increase of T. christiei but suppressed the other three species. 'Coastal' bermudagrass and 'Pensacola' bahiagrass (Paspalum notaturn) were not favorable for extensive development of any nematode species present. In longer term studies, of which these are a part, all four species survived for 10 years in relatively low numbers in bermudagrass and bahiagrass sods.

Ventriculoperitoneal shunt function: evaluation by sonography.

The function of ventriculoperitoneal shunts was evaluated by ultrasonography in 17 patients. In 10 of 15 patients with properly functioning shunts, a small amount of free intraperitoneal fluid was found. However, absence of demonstrable fluid did not reliably indicate shunt malfunction. No asymptomatic patients had large amounts of ascites or loculated fluid collections, both of which were considered pathologic in shunt patients.