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T Craig

Publications and source records attributed to T Craig.

At least 19 recordsLinked to original sources
PubMed2005

Internal fiducial markers can assist dose escalation in treatment of prostate cancer: result of organ motion simulations.

Use of internal fiducial markers and electronic portal imaging (EPI) to realign patients has been shown to significantly reduce positioning uncertainties in prostate radiation treatment. This creates the possibility of improving the treatment by decreasing the planning target volume (PTV) margin added to the clinical target volume (CTV), which in turn may allow dose escalation. Conformal treatment plans for three prostate cancer patients were evaluated by using different PTV margins with dose prescription of 70 Gy/35 fr initially. Two beam arrangements, 4-field-box (4FB) and 4-field-oblique (4FO), were used. Then, two dose escalation schemes, 74 Gy and 78 Gy, with tighter PTV margins, were chosen from the first simulation and were tested. A Monte Carlo model was developed to simulate the daily geometric uncertainty and calculate the dose to each organ. After the whole treatment, dose-volume histograms were produced and tumour control probability, prostate equivalent uniform dose and the effective dose to critical organs were calculated. By comparing these radiobiological metrics, optimized dose escalation schemes were found. The results show that using internal fiducial markers and EPI, the prescription dose can be escalated to 78 Gy/39 fr with a 4 mm PTV margin. Based on the available dose-response data for intermediate risk prostate patients, this is estimated to result in a 20% increase of local control and significantly reduced rectal complications.

Algorithms↗
PubMed2005

Mental health needs, service use and costs among Somali refugees in the UK.

OBJECTIVE: To assess the mental health needs and service use of Somali refugees living in London. METHOD: Subjects (n = 143) were sampled from conventional and non-conventional sites. Needs and service use were measured using the Camberwell Assessment of Need and the Client Service Receipt Inventory, respectively. Comparisons between sites were made and cost predictors identified. RESULTS: Basic needs occurred frequently but were often not fully addressed. The mean number of needs was around four out of a possible 22. The most used services were GPs, other clinicians and refugee services. Higher non-inpatient costs were associated with length of stay in the UK and lower costs with being at risk of suicide and having panic disorder or agoraphobia. CONCLUSION: Somali refugees living in London have a relatively high level of need but a low level of service use. Refugee characteristics could only account for a limited amount of cost variation.

Adult↗
PubMed2005

Pathways to care and ethnicity. 1: Sample characteristics and compulsory admission. Report from the AESOP study.

BACKGROUND: Many studies have found high levels of compulsory admission to psychiatric hospital in the UK among African-Caribbean and Black African patients with a psychotic illness. AIMS: To establish whether African-Caribbean and Black African ethnicity is associated with compulsory admission in an epidemiological sample of patients with a first episode of psychosis drawn from two UK centres. METHOD: All patients with a first episode of psychosis who made contact with psychiatric services over a 2-year period and were living in defined areas were included in the (AESOP) study. For this analysis we included all White British, other White, African-Caribbean and Black African patients from the AESOP sampling frame. Clinical, socio-demographic and pathways to care data were collected from patients, relatives and case notes. RESULTS: African-Caribbean patients were significantly more likely to be compulsorily admitted than White British patients, as were Black African patients. African-Caribbean men were the most likely to be compulsorily admitted. CONCLUSIONS: These findings suggest that factors are operating at or prior to first presentation to increase the risk of compulsory admission among African-Caribbean and Black African patients.

Adolescent↗
PubMed2005

Pathways to care and ethnicity. 2: Source of referral and help-seeking. Report from the AESOP study.

BACKGROUND: Previous research has found that African-Caribbean and Black African patients are likely to come into contact with mental health services via more negative routes, when compared with White patients. We sought to investigate pathways to mental health care and ethnicity in a sample of patients with a first episode of psychosis drawn from two UK centres. METHOD: We included all White British, other White, African-Caribbean and Black African patients with a first episode of psychosis who made contact with psychiatric services over a 2-year period and were living in defined areas. Clinical, socio-demographic and pathways to care data were collected from patients, relatives and case notes. RESULTS: Compared with White British patients, general practitioner referral was less frequent for both African-Caribbean and Black African patients and referral by a criminal justice agency was more common. With the exception of criminal justice referrals for Black African patients, these findings remained significant after adjusting for potential confounders. CONCLUSIONS: These findings suggest that factors are operating during a first episode of psychosis to increase the risk that the pathway to care for Black patients will involve non-health professionals.

Adolescent↗
PubMed2005

Psychiatry in Europe.

Explore the source record for details and available documents.

Cross-Cultural Comparison↗
PubMed2001

Considerations for the implementation of target volume protocols in radiation therapy.

PURPOSE: Uncertainties in patient repositioning and organ motion are accounted for by defining a planning target volume (PTV). We make recommendations on issues not explicitly discussed in existing protocols for PTV design. METHODS: A quantity called "coverage" is defined to quantify how effectively a PTV encompasses the clinical target volume, and is applied to examine the impact of several factors. A stochastic simulation is used to determine the coverage required for a desirable balance between tumor control probability (TCP) and the irradiated volume. Using a sample anatomy, we assess the importance of the method used to add uncertainties, the shape of the uncertainty distribution, the effect of systematic uncertainties, and the use of nonuniform margins. Additionally, we examine the benefit of patient immobilization techniques. RESULTS: Our example indicates that 95% coverage is a reasonable goal for treatment planning. Using this as a comparison value, our example indicates quadrature addition of uncertainties predicts smaller margins (7 mm) than linear addition (11 mm), Gaussian distribution of uncertainties (7 mm) require the same margin as a uniform distribution (7 mm), systematic uncertainties have a small effect on TCP below a threshold value (4 mm), and nonuniform margins allow only a slight reduction of irradiated volume. CONCLUSION: We recommend that uncertainties should generally be added in quadrature, the exact shape of the uncertainty distribution is not critical, systematic uncertainties should be maintained below some threshold value, and nonuniform margins may be effective when uncertainties are anisotropic.

Clinical Protocols↗
PubMed2001

gamma-Aminobutyric acid (GABA)--A function and binding in the paraventricular nucleus of the hypothalamus in chronic renal-wrap hypertension.

The goal of this study was to determine whether gamma-aminobutyric acid (GABA)ergic transmission and GABA binding are altered in chronic renal-wrap hypertension. Three groups of hypertensive and sham-operated rats were prepared for separate protocols. Four weeks later, the animals were prepared with femoral artery catheters for the measurement of mean arterial pressure. In all groups, blood pressure was significantly higher in the renal-wrapped animals. In the first study, bilateral microinjection of the GABA-A antagonist, bicuculline (50 pmol/site), into the paraventricular nucleus of the hypothalamus (PVN) caused a greater increase in arterial pressure (21.9+/-1.4 versus 16.7+/-1.8 mm Hg, P<0.05) and heart rate (135+/-15 versus 98+/-12 bpm, P=0.064) in hypertensive rats. [(3)H]Flunitrazepam was used to measure binding to the GABA-A receptor. Magnocellular neurons and the adjacent medial parvicellular neurons had more intense binding compared with the remainder of the PVN. B(max) was greater for the higher density binding area; the K(d) value was less in the high-density region. There were no differences in these parameters between normotensive and hypertensive animals. Competitive reverse transcription-polymerase chain reaction was used to measure the expression of mRNA for the alpha(1) subunit of the GABA-A receptor. No difference was observed in the mRNA between renal-wrapped and sham-operated rats. In summary, inhibition of GABA-A receptors in the PVN is augmented in the chronic phase of hypertension and is unrelated to a change in the expression of the number or affinity to the receptor. These findings suggest that the greater GABAergic activity is the result of an increase in GABA release in the PVN in chronic renal-wrap hypertension.

Animals↗
PubMed2001

Recovery from psychotic illness: a 15- and 25-year international follow-up study.

BACKGROUND: Poorly defined cohorts and weak study designs have hampered cross-cultural comparisons of course and outcome in schizophrenia. AIMS: To describe long-term outcome in 18 diverse treated incidence and prevalence cohorts. To compare mortality, 15- and 25-year illness trajectory and the predictive strength of selected baseline and short-term course variables. METHODS: Historic prospective study. Standardised assessments of course and outcome. RESULTS: About 75% traced. About 50% of surviving cases had favourable outcomes, but there was marked heterogeneity across geographic centres. In regression models, early (2-year) course patterns were the strongest predictor of 15-year outcome, but recovery varied by location; 16% of early unremitting cases achieved late-phase recovery. CONCLUSIONS: A significant proportion of treated incident cases of schizophrenia achieve favourable long-term outcome. Sociocultural conditions appear to modify long-term course. Early intervention programmes focused on social as well as pharmacological treatments may realise longer-term gains.

Adult↗
PubMed2000

Congruence of diagnoses 2 years after a first-admission diagnosis of psychosis.

BACKGROUND: Diagnostic changes may reflect evolution of an illness, emergence of newly disclosed information, or unreliability of assessment. This study evaluates the stability of research diagnoses in a heterogeneous first-admission sample with psychosis. METHODS: A group of 547 subjects initially diagnosed with a psychosis were reassessed 6 and 24 months after enrollment. The DSM-IV consensus diagnoses were formulated by psychiatrists blind to previous research diagnoses. The analysis focuses on agreement over time and the effects of demographic, family history, and clinical variables on the shift from a nonschizophrenia diagnosis to schizophrenia. RESULTS: Seventy-two percent of 6- and 24-month diagnoses were congruent. The most temporally consistent 6-month categories were schizophrenia (92%), bipolar disorder (83%), and major depression (74%); the least stable were psychosis not otherwise specified (44%), schizoaffective disorder (36%), and brief psychosis (27%). The most frequent shift in diagnosis at 24 months was to schizophrenia spectrum (n=45). These 45 subjects had a similar illness course after 6 months as the 171 subjects in this category at both assessments, but their prior clinical functioning was better. Risk factors predicting change to a schizophrenia spectrum diagnosis include facility variables (schizophrenia diagnosis, longer stays, and given antipsychotic medication on hospital discharge); prehospital features (psychotic > or =3 months before admission, poorer adolescent adjustment, lifetime substance disorder); and negative symptoms. CONCLUSIONS: Changes in diagnosis, particularly to schizophrenia, are mostly attributable to the evolution of the illness. Rigid adherence to DSM-IV requirements may have led to underdiagnosis of schizophrenia. The findings support the need for a longitudinally based diagnostic process in incidence samples.

Adolescent↗
PubMed2000

Persistent postoperative pain after the Chrisman-Snook ankle reconstruction.

One complication of the Chrisman-Snook ankle reconstruction is persistent postoperative pain. The incidence of this complication ranges from 7% to 60%. We report 10 cases of surgical exploration for persistent pain after Chrisman-Snook reconstructions. In 6 of the 10 cases a surgically correctable cause was found for the pain. The identified pathologic lesions in these 6 patients could have been prevented by careful attention to detail in the index operation. Surgical exploration should be considered for any of the following findings: persistent point tenderness (especially at the graft tunnel sites), localized swelling, a painful mass, recurrent instability/laxity, a symptomatic neuroma, or painful inversion and dorsiflexion. To prevent the complication of persistent postoperative pain after the Chrisman-Snook ankle reconstruction, we recommend the following: 1) avoid forced eversion when tensioning the graft, excessive posterior placement of the calcaneal tunnel, casting in eversion, and the use of nonabsorbable suture; 2) resect the distal muscle belly of the peroneus brevis muscle distal to the superior peroneal retinaculum; 3) check for tears in the peroneus brevis; 4) respect the sural nerve; and 5) obtain a watertight closure of the joint capsule. Although the Chrisman-Snook ankle reconstruction is an excellent technique, numerous pitfalls in surgical technique must be avoided.

Adolescent↗
PubMed1999

A quality assurance phantom for three-dimensional radiation treatment planning.

PURPOSE: Three-dimensional (3D) radiation treatment planning is facilitated through the use of computerized radiation treatment planning systems (RTPSs) and CT simulators (CT-sims). Quality assurance (QA) of these systems is necessary for ensuring that they fulfill their potential. However, comprehensive tools for the systematic QA of these systems have not been developed. We present a phantom that facilitates the evaluation of a large number of nondosimetric functions. These include CT image acquisition and transfer, graphical displays of 3D radiation beams, multiplanar CT image reconstructions, digitally reconstructed radiographs, the representation and manipulation of contoured patient anatomy, dose volume histograms, and the conversion of CT numbers to relative electron densities. METHODS AND MATERIALS: A phantom was constructed which contains materials and geometries that are appropriate for the routine QA of the features described above. The anatomy of the phantom is used as a standard against which the performance of the 3D-RTPS or CT-sim is evaluated. The phantom was used to evaluate three different 3D-RTPSs and a CT-sim at four institutions. RESULTS: Using this phantom, clinically significant errors and limitations in commercially available 3D treatment planning software were discovered. No errors were discovered in the beam display or image reconstructions in the systems examined. Problems were found in the anatomy display, automatic tools, and the CT number to relative electron density conversion data used in some of the systems. CONCLUSION: This phantom is a unique tool designed explicitly for the QA of 3D treatment planning software. Errors and limitations discovered through its use indicate that the QA of commercial treatment planning software is necessary, and that this phantom is an effective device for this task.

Image Processing, Computer-Assisted↗
PubMed1999

Six-month clinical status as a predictor of 24-month clinical outcome in first-admission patients with schizophrenia.

The aim of this study was to determine whether clinical status at 6-month follow-up is a predictor of 2-year clinical status in first-admission schizophrenic patients. If short-term status is indeed a strong predictor of subsequent functioning, the relationship would support earlier initiation of aggressive interventions. An epidemiologically based sample of 162 first-admission schizophrenic patients was examined at index hospitalization and at 6- and 24-month follow-up, using a variety of diagnostic and clinical assessment instruments. Respondents were divided into three groups based on their 6-month clinical status: delusions or hallucinations present at 6-month follow-up with or without negative symptoms (n = 63); moderate to high levels of negative symptoms (but not positive symptoms) present (n = 42); neither positive nor negative symptoms present (n = 57). Differences in 24-month clinical functioning were evaluated (GAF scores, BPRS factors, role functioning, number of rehospitalizations, and illness course). No significant differences were found among the three groups on demographic characteristics, substance abuse history, or extent of treatment during the follow-up. At 24-month follow-up, respondents with positive psychotic symptoms at 6-month follow-up had the worst, and those with no positive or negative symptoms the best functioning, with the negative-symptom group intermediate on most indices. Thus, among schizophrenic patients, poor 6-month clinical status identified a patient subgroup at high risk for continued poor clinical status at 24 months, suggesting the need for earlier intensive intervention in an attempt to prevent this progression.

Adolescent↗
PubMed1999

Effect of sinoaortic deafferentation on renal wrap hypertension.

The purpose of this study was to determine whether sinoaortic deafferentation (SAD) alters the severity of hypertension or sympathoadrenal contribution to mean blood pressure (MAP) during renal wrap hypertension. Male Sprague-Dawley rats were implanted with radiotelemetry transmitters for 24-hour recording of MAP and heart rate. All rats underwent either SAD or sham SAD (Intact) surgery and were allowed to recover for 10 to 14 days. The rats were then assigned to a normotensive (Sham) group or a hypertensive (Wrap) group in which 1-kidney figure-8 renal wrap was performed. SAD increased the acute MAP response to renal wrap (Intact-Sham=5+/-1 mm Hg, Intact-Wrap=45+/-3 mm Hg, SAD-Sham=3+/-3 mm Hg, SAD-Wrap=58+/-4 mm Hg) and increased the lability of MAP (SD of MAP; Intact-Sham=3.8+/-0.2, Intact-Wrap=4.2+/-0.3, SAD-Sham=9. 6+/-1.4, SAD-Wrap=9.7+/-1.4). MAP was not different between SAD and Intact rats during 4 weeks after renal wrap or sham surgery; however, induction of hypertension produced additional MAP variability that was independent of SAD (Intact-Sham=4.6+/-0.4, Intact-Wrap=6.2+/-0.6, SAD-Sham=6.3+/-0.5, SAD-Wrap=10.8+/-1.5). In a separate group of rats, the sympathoadrenal contribution to MAP was assessed by the depressor response to ganglionic blockade and plasma norepinephrine at rest and after neuronal uptake inhibition with desipramine. The depressor response to ganglionic blockade was significantly increased by renal wrap and by SAD (Intact-Sham=-49+/-2 mm Hg, Intact-Wrap=-73+/-4 mm Hg, SAD-Sham=-77+/-5 mm Hg, SAD-Wrap=-96+/-6 mm Hg). In the 3 groups with enhanced ganglionic blockade responses, desipramine caused a significant increase in plasma norepinephrine. These results indicate that SAD does not alter the development of renal wrap hypertension but does increase the sympathoadrenal contribution to MAP in both normotensive and hypertensive animals.

Afferent Pathways↗
PubMed1998

Use of immunotherapy in a primary care office.

Immunotherapy has been used for over 80 years. It is a safe and effective therapeutic intervention for allergic rhinitis, but its use in the treatment of asthma is more controversial. Patients with unstable asthma are at increased risk of adverse effects from immunotherapy; therefore, if immunotherapy is used in such patients, it should be instituted cautiously. Indications for immunotherapy include evidence of IgE-mediated disease and positive results on skin tests or radioallergosorbent test (RAST). In addition, before immunotherapy is considered, measures to avoid exposure to offending agents and drug therapy should have failed to provide relief of symptoms. Before administering immunotherapy in the office, physicians should be knowledgeable about the use of immunotherapy and the treatment of anaphylaxis, and should have ready access to the equipment needed to avert anaphylaxis.

Asthma↗
PubMed1998

Seasonal allergic conjunctivitis.

Seasonal allergic conjunctivitis is rarely associated with permanent vision impairment; however, it is a relatively common condition that may compromise the quality of life of patients with this diagnosis. In extreme cases daily activities, including work, may be compromised. Numerous treatment options have become available for the relief of acute symptoms. Corticosteroids may be used for severe cases for a limited time. If topical corticosteroids are being considered, an ophthalmologist should be consulted. Decongestants and antihistamines are useful treatment options for the majority of cases. Antihistamines, either topical or oral, should be the first-line therapy. Ketorolac may be helpful in relieving pruritus but offers little advantage over topical antihistamines. Sodium cromoglycate and lodoxamide may be helpful in the prophylaxis of symptoms during the allergy season but require frequent dosing. Immunotherapy is effective and should be offered to those who are intolerant or refractory to medications. Obviously, avoidance should always be the first choice in therapy but in most cases is not practical, especially with pollen allergies. The use of saline eyedrops is simple, nontoxic and is effective in up to 30-35% of cases. It can and should be added to all other remedies to reduce adverse effects and cost by decreasing the need for other therapeutic options.

Journal Article↗
PubMed1997

Ischemic-reperfusion injury in the kidney: overexpression of colonic H+-K+-ATPase and suppression of NHE-3.

Ischemic renal injury is associated with changes in the expression of a number of genes. Although pH regulation is undoubtedly important during the recovery from ischemia, the expression of acid-base transporters during acute ischemic renal failure has not been studied. In the present study, levels of mRNA encoding the colonic H+-K+-ATPase and four isoforms of the Na+/H+ exchanger (NHE-1, NHE-2, NHE-3 and NHE-4) were measured by quantitative Northern analysis in rat renal cortex and medulla following ischemia-reperfusion injury. Rats were subjected to 30 minutes of renal artery occlusion and then sacrificed either 12 or 24 hours after the occlusion was released. The most striking changes followed 30 minutes of occlusion and 12 hours of reperfusion and involved the mRNA for NHE-3 (involved in HCO3- reabsorption in proximal tubule and thick limb) and colonic H+-K+-ATPase (involved in HCO3- reabsorption in collecting duct). These changes were: (1) a approximately 75% decrease in NHE-3 mRNA in both cortex and medulla; and (2) an approximately 8-fold increase in colonic H+-K+-ATPase mRNA in the cortex. At 12 hours of reperfusion, there was a 66% reduction in the Na+/H+ exchanger (NHE-3) activity as assayed by acid-stimulated 22Na+ influx into brush border membrane vesicles (P < 0.01). After 24 hours of reperfusion, NHE-3 mRNA remained suppressed while cortical colonic H+-K+-ATPase mRNA declined to only twice the control level. Medullary colonic H+-K+-ATPase mRNA did not change significantly. Gastric H+-K+-ATPase mRNA in cortex or medulla remained the same at 0, 12, and 24 hours after reperfusion. Cortical NHE-1 increased mildly at 12 and 24 hours of reperfusion whereas a moderate decrease in NHE-2 and NHE-4 mRNAs was observed in cortex and medulla after both 12 and 24 hours of reperfusion. We suggest that overexpression of colonic H+-K+-ATPase in the early phase of renal reperfusion injury may be responsible for compensatory reabsorption of increased HCO3- load resulting from suppression of NHE-3. This was supported by a fourfold increase in colonic H+-K+-ATPase mRNA in rats treated with acetazolamide, which causes renal HCO3-wasting. Rapid decline in colonic H+-K+-ATPase expression at 24 hours after reperfusion is likely due to reduced HCO3- delivery to distal tubules resulting from decreased GFR. Overexpression of H+-K+-ATPase may be vital to acid-base homeostasis in the early phase of acute ischemic renal failure.

Animals↗