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S Stapleton

Publications and source records attributed to S Stapleton.

11 recordsLinked to original sources
PubMed2007

Retrospective analysis of 49 cases of brain abscess and review of the literature.

The case records of 49 patients discharged from St George's Hospital, London, between December 2000 and March 2004 with the diagnosis of brain abscess were reviewed in order to document the epidemiology, causes, treatment, and prognostic factors associated with brain abscess. Brain abscess occurred at all ages, more frequently in men than in women. Headache and altered mental status were common presenting symptoms. The frontal lobe was the most common site. Streptococcal infection was seen most commonly, but staphylococcal infection predominated in cases following neurosurgery. Computed tomography provided sufficient diagnostic information in most cases. All but five patients had early surgical drainage. Cefotaxime and metronidazole were used most often for empirical therapy. Thirty-nine patients recovered fully or had minimal incapacity. Five patients died. Patients with underlying cranial neoplasms or medical conditions had a worse outcome than those with a contiguous focus of infection or post-traumatic abscess. Changes in disease pattern were determined by comparison to a literature review. A PubMed search of the literature using the keywords "brain abscess" was undertaken, and identified papers and relevant citations were reviewed. Compared to earlier series, there was a marked decrease in the number of cases of brain abscess secondary to otitis media and congenital heart disease. There was an increase in the number of cases of brain abscess secondary to neurosurgery and trauma. Changes in the epidemiology of predisposing conditions for brain abscess are associated with changes in the patient population and causative organisms. Though still a potentially fatal infection, there have been recent improvements in diagnosis, treatment, and outcome.

Adolescent↗
PubMed2005

Implementation of random set-up errors in Monte Carlo calculated dynamic IMRT treatment plans.

The fluence-convolution method for incorporating random set-up errors (RSE) into the Monte Carlo treatment planning dose calculations was previously proposed by Beckham et al, and it was validated for open field radiotherapy treatments. This study confirms the applicability of the fluence-convolution method for dynamic intensity modulated radiotherapy (IMRT) dose calculations and evaluates the impact of set-up uncertainties on a clinical IMRT dose distribution. BEAMnrc and DOSXYZnrc codes were used for Monte Carlo calculations. A sliding window IMRT delivery was simulated using a dynamic multi-leaf collimator (DMLC) transport model developed by Keall et al. The dose distributions were benchmarked for dynamic IMRT fields using extended dose range (EDR) film, accumulating the dose from 16 subsequent fractions shifted randomly. Agreement of calculated and measured relative dose values was well within statistical uncertainty. A clinical seven field sliding window IMRT head and neck treatment was then simulated and the effects of random set-up errors (standard deviation of 2 mm) were evaluated. The dose-volume histograms calculated in the PTV with and without corrections for RSE showed only small differences indicating a reduction of the volume of high dose region due to set-up errors. As well, it showed that adequate coverage of the PTV was maintained when RSE was incorporated. Slice-by-slice comparison of the dose distributions revealed differences of up to 5.6%. The incorporation of set-up errors altered the position of the hot spot in the plan. This work demonstrated validity of implementation of the fluence-convolution method to dynamic IMRT Monte Carlo dose calculations. It also showed that accounting for the set-up errors could be essential for correct identification of the value and position of the hot spot.

Algorithms↗
PubMed2005

Aneurysmal bone cyst of the spine.

The authors present the case of an 11-year-old boy with a painful, rapidly expanding lesion in the posterior triangle of the neck. There was no history of cervical trauma. Computerized tomography of the neck revealed a unicameral (single-chambered) aneurysmal bone cyst involving the C3 vertebra. Treatment was by open resection and curettage; no recurrence was seen at six months. We discuss the natural history, differential diagnosis, radiographic appearance and treatment modalities for this unusual, benign, expanding, osteolytic lesion containing blood-filled cystic cavities.

Bone Cysts, Aneurysmal↗
PubMed2001

"Anorexia saved my life": coincidental anorexia nervosa and cerebral meningioma.

OBJECTIVE: We report on a 13-year-old girl with coincidental occult intracranial tumor and early-onset anorexia nervosa. METHOD: The cerebral meningioma was discovered fortuitously as the result of a research project using SPECT imaging to locate a neurobiological substrate in patients with anorexia nervosa. Without SPECT, the meningioma would have remained undiagnosed until it had become symptomatic. The two conditions appear to have been completely unrelated. RESULTS AND DISCUSSION: The case highlights two important points. First, intracranial pathology should also be considered however certain is the diagnosis of early-onset anorexia nervosa. Second, neuroimaging plays an important part in diagnosing early-onset anorexia nervosa, both from a clinical and a research prospective.

Adolescent↗
PubMed2001

Gliomatosis cerebri: pitfalls in diagnosis.

We report two young patients with obscure presentations of gliomatosis cerebri. Initial CT scanning was inconclusive and in one case showed intraventricular haemorrhage, a feature not previously described. Magnetic resonance imaging was required to show the lesions with greater definition; however, in both cases, a biopsy was needed to confirm the diagnosis.

Adult↗
PubMed1996

Acquired immune deficiency syndrome (AIDS) and cerebral astrocytoma.

The presence of cerebral lesions in patients affected by the acquired immune deficiency syndrome (AIDS) has been estimated to be around 10%, with the majority being infective lesions or primary central nervous system lymphomas. The co-occurrence of a cerebral glioma in such patients is rare. The aim of this report is to present four more cases, discussing their clinical and neuroradiological features, as well as the outcome and the possible pathogenesis.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Continuous arteriovenous hemofiltration: an alternative dialysis therapy in neonates.

Modifications have made it possible to perform CAVH in the neonate. One of these is decreasing the extravascular volume in the tubing and filter to a minimal amount to allow for adequate intravascular blood volume in the infant. Another is utilizing predilutional fluid to decrease the need for heparinization. A third modification is utilizing the suction-assist pumps to help control the amount of fluid removed from the infant. With modifications of this system to fit the special needs of neonates and intensive nursing and medical management, CAVH can be a successful alternative to traditional dialysis therapies in neonates.

Acute Kidney Injury↗
PubMed1989

Outcomes of care in birth centers. The National Birth Center Study.

We studied 11,814 women admitted for labor and delivery to 84 free-standing birth centers in the United States and followed their course and that of their infants through delivery or transfer to a hospital and for at least four weeks thereafter. The women were at lower-than-average risk of a poor outcome of pregnancy, according to many but not all of the recognized demographic and behavioral risk factors. Among the women, 70.7 percent had only minor complications or none; 7.9 percent had serious emergency complications during labor and delivery or soon thereafter, such as thick meconium or severe shoulder dystocia. One woman in six (15.8 percent) was transferred to a hospital; 2.4 percent had emergency transfers. Twenty-nine percent of nulliparous women and only 7 percent of parous women were transferred, but the frequency of emergency transfers was the same. The rate of cesarean section was 4.4 percent. There were no maternal deaths. The overall intrapartum and neonatal mortality rate was 1.3 per 1000 births. The rates of infant mortality and low Apgar scores were similar to those reported in large studies of low-risk hospital births. We conclude that birth centers offer a safe and acceptable alternative to hospital confinement for selected pregnant women, particularly those who have previously had children, and that such care leads to relatively few cesarean sections.

Adolescent↗
PubMed1979

Specular microscopic observations of the clinically normal canine corneal endothelium.

Specular microscopy and pachometry were performed on seven clinically normal anesthetized young adult dogs. Endothelial cells of the central cornea formed a mosaic-like pattern of hexagonal cells 15 to 20 micrometers in diameter; the average number of cells per millimeters squared was 2,816 +/- 187 SD. Average corneal thickness of 0.62 +/- 0.047 SD mm.

Animals↗