A Network Analysis of 15O-H2O PET Reveals Deep Brain Stimulation Effects on Brain Network of Parkinson's Disease

Purpose

As Parkinson''s disease (PD) can be considered a network abnormality, the effects of deep brain stimulation (DBS) need to be investigated in the aspect of networks. This study aimed to examine how DBS of the bilateral subthalamic nucleus (STN) affects the motor networks of patients with idiopathic PD during motor performance and to show the feasibility of the network analysis using cross-sectional positron emission tomography (PET) images in DBS studies.

Materials and Methods

We obtained [¹⁵O]H₂O PET images from ten patients with PD during a sequential finger-to-thumb opposition task and during the resting state, with DBS-On and DBS-Off at STN. To identify the alteration of motor networks in PD and their changes due to STN-DBS, we applied independent component analysis (ICA) to all the cross-sectional PET images. We analysed the strength of each component according to DBS effects, task effects and interaction effects.

Results

ICA blindly decomposed components of functionally associated distributed clusters, which were comparable to the results of univariate statistical parametric mapping. ICA further revealed that STN-DBS modifies usage-strengths of components corresponding to the basal ganglia-thalamo-cortical circuits in PD patients by increasing the hypoactive basal ganglia and by suppressing the hyperactive cortical motor areas, ventrolateral thalamus and cerebellum.

Conclusion

Our results suggest that STN-DBS may affect not only the abnormal local activity, but also alter brain networks in patients with PD. This study also demonstrated the usefulness of ICA for cross-sectional PET data to reveal network modifications due to DBS, which was not observable using the subtraction method.     

Electrode position and the clinical outcome after bilateral subthalamic nucleus stimulation

We compared the surgical outcome with electrode positions after bilateral subthalamic nucleus (STN) stimulation surgery for Parkinson's disease. Fifty-seven patients treated with bilateral STN stimulations were included in this study. Electrode positions were determined in the fused images of preoperative MRI and postoperative CT taken at six months after surgery. The patients were divided into three groups: group I, both electrodes in the STN; group II, only one electrode in the STN; group III, neither electrode in the STN. Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn and Yahr stage, and activities of daily living scores significantly improved at 6 and 12 months after STN stimulation in both group I and II. The off-time UPDRS III speech subscore significantly improved (1.6 ± 0.7 at baseline vs 1.3 ± 0.8 at 6 and 12 months, P < 0.01) with least L-dopa equivalent daily dose (LEDD) (844.6 ± 364.1 mg/day at baseline; 279.4 ± 274.6 mg/day at 6 months; and 276.0 ± 301.6 mg/day at 12 months, P < 0.001) at 6 and 12 months after STN deep brain stimulation (DBS) in the group I. Our findings suggest that the better symptom relief including speech with a reduced LEDD is expected in the patients whose electrodes are accurately positioned in both STN.     

Evidence of Subthalamic PGO-like Waves During REM Sleep in Humans: A Deep Brain Polysomnographic Study

Study Objectives:

The aim of this study was to examine whether the subthalamic nucleus (STN) plays a role in the transmission of PGO-like waves during REM sleep in humans.

Design:

Simultaneous recordings from deep brain electrodes to record local field potentials (LFPs), and standard polysomnography to ascertain sleep/wake states.

Setting:

Main Hospital, department of clinical neurophysiology sleep laboratory.

Participants:

12 individuals with Parkinson''s disease, with electrodes implanted in the STN; and, as a control for localization purposes, 4 cluster headache patients with electrodes implanted in the posterior hypothalamus.

Interventions:

All subjects underwent functional neurosurgery for implantation of deep brain stimulation electrodes.

Results:

Sharp, polarity-reversed LFPs were recorded within the STN during REM sleep in humans. These subthalamic PGO-like waves (2–3 Hz, 80–200 μV, and 300–500 msec) appeared during REM epochs as singlets or in clusters of 3–13 waves. During the pre-REM period, subthalamic PGO-like waves were temporally related to drops in the submental electromyogram and/or onset of muscular atonia. Clusters of PGO-like waves occurred typically before and during the bursts of rapid eye movements and were associated with an enhancement in fast (15–35 Hz) subthalamic oscillatory activity.

Conclusion:

Subthalamic PGO-like waves can be recorded during pre-REM and REM sleep in humans. Our data suggest that the STN may play an active role in an ascending activating network implicated in the transmission of PGO waves during REM sleep in humans.

Citation:

Fernández-Mendoza J; Lozano B; Seijo F; Santamarta-Liébana E; Ramos-Platón MJ; Vela-Bueno A; Fernández-González F. Evidence of subthalamic PGO-like waves during REM sleep in humans: a deep brain polysomnographic study. SLEEP 2009;32(9):1117-1126.     

Influence of Propofol and Fentanyl on Deep Brain Stimulation of the Subthalamic Nucleus

We investigated the effect of propofol and fentanyl on microelectrode recording (MER) and its clinical applicability during subthalamic nucleus (STN) deep brain stimulation (DBS) surgery. We analyzed 8 patients with Parkinson''s disease, underwent bilateral STN DBS with MER. Their left sides were done under awake and then their right sides were done with a continuous infusion of propofol and fentanyl under local anesthesia. The electrode position was evaluated by preoperative MRI and postoperative CT. The clinical outcomes were assessed at six months after surgery. We isolated single unit activities from the left and the right side MERs. There was no significant difference in the mean firing rate between the left side MERs (38.7±16.8 spikes/sec, n=78) and the right side MERs (35.5±17.2 spikes/sec, n=66). The bursting pattern of spikes was more frequently observed in the right STN than in the left STN. All the electrode positions were within the STNs on both sides and the off-time Unified Parkinson''s Disease Rating Scale part III scores at six months after surgery decreased by 67% of the preoperative level. In this study, a continuous infusion of propofol and fentanyl did not significantly interfere with the MER signals from the STN. The results of this study suggest that propofol and fentanyl can be used for STN DBS in patients with advanced Parkinson''s disease improving the overall experience of the patients.

Graphical Abstract

相似文献   

Anti-Allodynic Effects of Levodopa in Neuropathic Rats

Purpose

Levodopa is the most effective anti-Parkinsonian agent. It has also been known to exhibit analgesic properties in laboratory and clinical settings. However, studies evaluating its effects on neuropathic pain are limited. The aim of the present study was to examine the anti-allodynic effects of levodopa in neuropathic rats.

Materials and Methods

Sprague-Dawley male rats underwent the surgical procedure for L5 and L6 spinal nerves ligation. Sixty neuropathic rats were randomly divided into 6 groups for the oral administration of distilled water and levodopa at 10, 30, 50, 70, and 100 mg/kg, respectively. We co-administered carbidopa with levodopa to prevent peripheral synthesis of dopamine from levodopa, and observed tactile, cold, and heat allodynia pre-administration, and at 15, 30, 60, 90, 120, 150, 180, and 240 min after drug administration. We also measured locomotor function of neuropathic rats using rotarod test to examine whether levodopa caused side effects or not.

Results

Distilled water group didn''t show any difference in all allodynia. For the levodopa groups (10-100 mg/kg), tactile and heat withdrawal thresholds were increased, and cold withdrawal frequency was decreased dose-dependently (p<0.01). In addition, levodopa induced biphasic analgesia. Different dosage of levodopa did not impact on the rotarod time (p>0.05).

Conclusion

Levodopa reversed tactile, cold and heat allodynia in neuropathic rat without any side effects.     

Early nephrology care provided by the nephrologist alone is not sufficient to mitigate the social and psychological aspects of chronic kidney disease

OBJECTIVE:

Patients with chronic kidney disease who receive early nephrology care have a better prognosis with maintenance dialysis. We aimed to determine whether early referral to a nephrologist can also improve the psychological burden of having chronic kidney disease.

SUBJECTS AND METHODS:

Thirty‐nine patients with chronic kidney disease that required hemodialysis were studied: 19 had a ≥ 6-month history of nephrology care (Group1), and 20 had never received any prior nephrology care (Group2). All patients participated in a semi‐structured interview that addressed their perceived knowledge and psychological aspects related to CKD and hemodialysis. Demographic and laboratory data as well as socioeconomic status were evaluated.

RESULTS:

In both groups, most of the patients were of low socioeconomic status. Group 1 had significantly better laboratory parameters (p<0.05). The patients'' answers to the questions showed no differences between the groups: 63% of Group 1 and 55% of Group 2 reported that they had no prior knowledge about dialysis; 58% and 40%, respectively, reported that they “don''t completely understand what the doctor says”; and 74% and 85%, respectively, believed that their “kidneys would work again”.

CONCLUSION:

Pre‐dialysis nephrology care improves the clinical conditions of the patients with chronic kidney disease but is insufficient for minimizing other aspects of having chronic kidney disease.     

Association between mean platelet volume levels and inflammation in SLE patients presented with arthritis

Background

Systemic lupus erythematosus (SLE) may be characterized by periods of remissions and chronic or acute relapses. The complexity of clinical presentation of the SLE patients leads to incorrect evaluation of disease activity. Mean platelet volume (MPV) has been studied as a simple inflammatory marker in several diseases. There is no study in the literature about MPV levels in adult SLE patients with arthritis.

Objectives

We aimed to investigate the MPV levels in the SLE population with arthritis during and between activations.

Methods

The study consisted of 44 SLE patients with arthritis in activation period (Group 1), the same 44 SLE patients with arthritis in remission period (Group 2) and 44 healthy controls (Group 3). Erythrocyte sedimentation rate (ESR), creactive protein (CRP), white blood cell count, platelet count, and mean platelet volume (MPV) levels were retrospectively recorded from patient files.

Results

The mean ages of the SLE subjects were 42 ± 16 years, while the mean ages of controls was 41 ± 17 years. MPV was significantly lower in Group 1(7.66±0.89fL) than in Group 2 (8.61±1.06 fL) and Group 3(8.62±1.11fL) (p<0.0001). The differences between groups reached statistical significance.

Conclusions

We suggest that MPV levels decrease in patients with arthritis of SLE activation when compared to the same patients in remission and healthy controls.     

Effect of the Starting Point of Half-Pin Insertion on the Insertional Torque of the Pin at the Tibia

Purpose

The authors have observed a failure to achieve secure fixation in elderly patients when inserting a half-pin at the anteromedial surface of the tibia. The purpose of this study was to compare two methods for inserting a half-pin at tibia diaphysis in elderly patients.

Materials and Methods

Twenty cadaveric tibias were divided into Group C or V. A half-pin was inserted into the tibias of Group C via the conventional method, from the anteromedial surface to the interosseous border of the tibia diaphysis, and into the tibias of Group V via the vertical method, from the anterior border to the posterior surface at the same level. The maximum insertion torque was measured during the bicortical insertion with a torque driver. The thickness of the cortex was measured by micro-computed tomography. The relationship between the thickness of the cortex engaged and the insertion torque was investigated.

Results

The maximum insertion torque and the thickness of the cortex were significantly higher in Group V than Group C. Both groups exhibited a statistically significant linear correlation between torque and thickness by Spearman''s rank correlation analysis.

Conclusion

Half-pins inserted by the vertical method achieved purchase of more cortex than those inserted by the conventional method. Considering that cortical thickness and insertion torque in Group V were significantly greater than those in Group C, we suggest that the vertical method of half-pin insertion may be an alternative to the conventional method in elderly patients.     

Changes in Spinal Canal Diameter and Vertebral Body Height with Age

Purpose

All structures of the spine, including the spinal canal, change continuously with age. The purpose of this study was to determine how the spinal canal of the lumbar spine changes with age. The L4/5 is the most common site of spinal stenosis and has the largest flexion-extension motion, whereas the T5/6 has the least motion. Therefore, we measured the spinal canal diameter and vertebral body height at T5, T6, L4, and L5 with age.

Materials and Methods

This was a retrospective study of aged 40 to 77 years. We reviewed whole spine sagittal MRIs of 370 patients with lumbar spinal stenosis (LSS) (Group 2) and 166 herniated cervical disc (HCD) (Group 1). Each group was divided into four age groups, and demographic parameters (age, gender, height, weight, BMI), the mid-spinal canal diameter, and mid-vertebrae height at T5, T6, L4, L5 were compared. Within- and between-group comparisons were made to evaluate changes by age and correlations were carried out to evaluate the relationships between all parameters.

Results

Height, weight, and all radiologic parameters were significantly lower in Group 2 than Group 1. Group 1 did not show any differences, when based on age, but in Group 2, height, weight, and T6, L4, and L5 height were significantly decreased in patients in their 70''s than patients in their 40''s, except for spinal canal diameter. Age was associated with all parameters except spinal canal diameter.

Conclusion

Vertebral height decreased with age, but spinal canal diameter did not change in patients with either LSS or HCD. Mid-spinal canal diameter was not affected by aging.     

Effects of a multidisciplinary cognitive rehabilitation program for patients with mild Alzheimer's disease

OBJECTIVE:

To evaluate the effects of a multidisciplinary rehabilitation program on cognition, quality of life, and neuropsychiatric symptoms in patients with mild Alzheimer''s disease.

METHOD:

The present study was a single-blind, controlled study that was conducted at a university-based day-hospital memory facility. The study included 25 Alzheimer''s patients and their caregivers and involved a 12-week stimulation and psychoeducational program. The comparison group consisted of 16 Alzheimer''s patients in waiting lists for future intervention.

INTERVENTION:

Group sessions were provided by a multiprofessional team and included memory training, computer-assisted cognitive stimulation, expressive activities (painting, verbal expression, writing), physiotherapy, and physical training. Treatment was administered twice a week during 6.5-h gatherings.

MEASUREMENTS:

The assessment battery comprised the following tests: Mini-Mental State Examination, Short Cognitive Test, Quality of Life in Alzheimer''s disease, Neuropsychiatric Inventory, and Geriatric Depression Scale. Test scores were evaluated at baseline and the end of the study by raters who were blinded to the group assignments.

RESULTS:

Measurements of global cognitive function and performance on attention tasks indicated that patients in the experimental group remained stable, whereas controls displayed mild but significant worsening. The intervention was associated with reduced depression symptoms for patients and caregivers and decreased neuropsychiatric symptoms in Alzheimer''s subjects. The treatment was also beneficial for the patients'' quality of life.

CONCLUSION:

This multimodal rehabilitation program was associated with cognitive stability and significant improvements in the quality of life for Alzheimer''s patients. We also observed a significant decrease in depressive symptoms and caregiver burden. These results support the notion that structured nonpharmacological interventions can yield adjunct and clinically relevant benefits in dementia treatment.     

The Efficacy of Physical Therapy and Physical Therapy Plus Calcitonin in the Treatment of Lumbar Spinal Stenosis

Purpose

The aim of our study was to compare the efficacy of physical therapy alone and in combination with calcitonin in patients with neurogenic claudication (NC).

Materials and Methods

In this single blind, and randomized study, patients with lumbar spinal canal stenosis who were diagnosed by clinical findings and MRI and having NC were included. Patients were observed for 8 weeks and evaluated before and after treatment. Patients were randomized between the salmon calcitonin 200 U/day + physical therapy (n = 23) (Group 1) and paracetamol 1,500 mg/day + physical therapy (n = 22) (Group 2) treatment groups. Both groups received the same physical therapy (interferential current + hot pack + short wave diathermy) and exercise protocol. The association of various clinical and functional parameters was assessed statistically by using paired and unpaired t test, chi square test and McNemar''s test. p < 0.05 indicated statistical significant.

Results

Mean age of the patients in Group 1 was 57.6 ± 11.2 and in Group 2 54.5 ± 10.6 years. Before treatment, there were no significant differences between groups with respect to age, body mass index, spinal axial diameter, Visual Analogue Scale (VAS), spinal mobility, functional status and walking distance (p > 0.05). After 8 weeks of treatment, both groups benefited significantly with respect to VAS, functional status and walking distance (p < 0.001). There was no statistically significant difference between groups (p > 0.05).

Conclusion

In 45 patients with lumbar spinal stenosis who received 8 weeks of treatment, concomitant use of calcitonin with physical therapy and exercise did not have any benefical effect on the patient''s pain, functional status, lumbar mobility and walking distance.     

Clinical profile of Parkinson's disease in the Gumei community of Minhang district,Shanghai

OBJECTIVE:

We examined the demographic and clinical profiles of Parkinson''s disease in Shanghai, China, to assist in disease management and provide comparative data on Parkinson''s disease prevalence, phenotype, and progression among different regions and ethnic groups.

METHODS:

A door-to-door survey and follow-up clinical examinations identified 180 community-dwelling Han-Chinese Parkinson''s disease patients (104 males, 76 females).

RESULTS:

The average age at onset was 65.16±9.60 years. The most common initial symptom was tremor (112 patients, 62.22%), followed by rigidity (38, 21.11%), bradykinesia (28, 15.56%) and tremor plus rigidity (2, 1.11%). Tremor as the initial symptom usually began in a single limb (83.04% of patients). The average duration from onset to mild Parkinson''s disease (Hoehn-Yahr phase 1–2) was 52.74±45.64 months. Progression from mild to moderate/severe Parkinson''s disease (phase≥3) was significantly slower (87.07±58.72 months; p<0.001), except for patients presenting initially with bradykinesia (53.83±24.49 months). Most patients (149/180, 82.78%) took levodopa with or without other drugs. The Hamilton Anxiety Scale revealed symptoms of clinical anxiety in 35 patients, and the Hamilton Depression Scale revealed depressive symptoms in 88 patients. The depressed or anxious subgroup (123 patients) demonstrated a significantly younger age at onset (55.54±7.68 years) compared with the overall mean (p<0.05).

CONCLUSION:

Unilateral limb tremor was the most common initial symptom, and motor function deteriorated slowly over ≈4−9 years. Earlier-onset patients experience greater psychiatric dysfunction.     

Predicting lymph node status in patients with early gastric carcinoma using double contrast-enhanced ultrasonography

Introduction

Double contrast-enhanced ultrasonography (DCUS) is a new method we used in predicting lymph node metastasis (LNM) in patients with early gastric cancer.

Material and methods

Seventy-six patients with early gastric cancer diagnosed by gastroscope and confirmed by pathology after operation were examined using DCUS preoperatively. Group N1 included 15 patients with LNM and group N0 61 patients without LNM.

Results

In group N1, 13 patients (87%) had marked hyperenhancement during early arterial phase using DCUS, and 2 patients (13%) were unmarked as hyperenhancement. In group N0, 24 patients (39%) had marked hyperenhancement during early arterial phase using DCUS, and 37 patients (61%) had unmarked hyperenhancement. The sensitivity and specificity of marked hyperenhancement in predicting LNM in patients with early gastric cancer was 86.7% and 60.7% respectively, and the Youden’s index was 0.474. The κ value of this method was 0.89.

Conclusions

Double contrast-enhanced ultrasonography is a new valuable method to evaluate LNM at an early stage of gastric cancer and prognosis of early gastric cancer preoperatively.     

Outcome of knee injuries in general practice: 1-year follow-up

Background

Knee injuries may lead to pain and to functional limitations in the activities of daily living. Patients with knee injuries are frequently seen in general practice; however, the outcome and management in these patients is not known.

Aim

To assess the outcome and management of knee injuries at 12 months'' follow-up in general practice.

Design of study

A prospective observational cohort study with a 1-year follow-up.

Setting

Primary health care.

Method

Adult patients consulting their GP after knee injury (n = 134) participated in the cohort. A magnetic resonance imaging scan was carried out and patients were diagnosed as either no lesion or an isolated meniscal tear, an isolated collateral or cruciate ligament lesion, or a combination. Follow-up questionnaires were filled in up to 12 months'' follow-up.

Results

At 12 months'' follow-up, 34 patients reported full recovery and 67 patients reported major improvement. At baseline, 37 patients (28%) were referred to physical therapy and 17 patients (13%) were referred to secondary care. During 1 year of follow-up, another 21 referrals to physical therapy and 11 referrals to secondary care took place. The pain severity decreased the most, and the Lysholm knee score increased in the majority of patients during the first 3 months after injury. In total, 18 arthroscopies were performed in 15 patients. One patient underwent an anterior cruciate ligament reconstruction.

Conclusion

The vast majority of patients report clinically relevant recovery. There is no clear difference in outcomes between patients with meniscal tears or ligament lesions and patients without these diagnoses.     

Spinal Cord Hemangioblastomas in von Hippel-Lindau Disease: Management of Asymptomatic and Symptomatic Tumors

Purpose

Standard treatment of asymptomatic spinal cord hemangioblastoma in von Hippel-Lindau (VHL) disease has yet to be established. The purpose of this study was to propose guidelines for the treatment of asymptomatic spinal cord hemangioblastomas in VHL disease.

Materials and Methods

VHL disease patients treated for spinal cord hemangioblastomas between 1999 and 2009 were included. All spinal cord hemangioblastomas were divided into three groups: Group 1, asymptomatic tumors at initial diagnosis followed with serial imaging studies; Group 2, asymptomatic tumors at initial diagnosis that were subsequently resected; and Group 3, symptomatic tumors at initial diagnosis, all of which were resected.

Results

We identified 24 spinal cord hemangioblastomas in 12 patients. Groups 1, 2 and 3 comprised 13, 4 and 7 tumors, respectively. Group 1 exhibited a smaller tumor volume (257.1 mm³) and syrinx size (0.8 vertebral columns) than those of Group 2 (1304.5 mm³, 3.3 vertebral columns) and Group 3 (1787.4 mm³, 6.1 vertebral columns). No difference in tumor volume or syrinx size was observed between Groups 2 and 3. Five tumors in Group 1 were resected during follow-up because symptoms had developed or the tumor had significantly grown. Finally, among 17 asymptomatic tumors at the initial diagnosis, nine tumors were resected. Only one tumor of these nine tumors resulted in neurological deficits, while five of seven symptomatic tumors caused neurological deficits.

Conclusion

Selective resection of asymptomatic tumors before they cause neurological deficits might bring about better outcomes.     

Pulmonary toxicity of chronic exposure to tobacco and biomass smoke in rats

OBJECTIVE:

The objective of this study was to examine the separate and combined effects of tobacco and biomass smoke exposure on pulmonary histopathology in rats.

INTRODUCTION:

In addition to smoking, indoor pollution in developing countries contributes to the development of respiratory diseases.

METHODS:

Twenty-eight adult rats were divided into four groups as follows: control group (Group I, no exposure to tobacco or biomass smoke), exposed to tobacco smoke (Group II), exposed to biomass smoke (Group III), and combined exposure to tobacco and biomass smoke (Group IV). After six months the rats in all four groups were sacrificed. Lung tissue samples were examined under light microscopy. The severity of pathological changes was scored.

RESULTS:

Group II differed from Group I in all histopathological alterations except intraparenchymal vascular thrombosis. There was no statistically significant difference in histopathological changes between the subjects exposed exclusively to tobacco smoke (Group II) and those with combined exposure to tobacco and biomass smoke (Group IV). The histopathological changes observed in Group IV were found to be more severe than those in subjects exposed exclusively to biomass smoke (Group III).

DISCUSSION:

Chronic exposure to tobacco and biomass smoke caused an increase in severity and types of lung injury.

CONCLUSION:

Exposure to cigarette smoke caused serious damage to the respiratory system, particularly with concomitant exposure to biomass smoke.     

Significance of Neoadjuvant Hormonal Therapy in Radical Retropubic Prostatectomy: A Retrospective Single-Surgeon Study

Purpose

The purpose of this study was to evaluate whether neo-adjuvant hormonal therapy (NHT) prior to radical retropubic prostatectomy (RRP) for prostate cancer (PCa) is beneficial in terms of surgical outcomes and for preventing or delaying biochemical recurrence via single-surgeon case series study.

Materials and Methods

Fifty-three men underwent RRP by a single surgeon. The patients were divided into two groups according to whether or not NHT was performed prior to RRP. The study was analyzed retrospectively. We evaluated clinical parameters, surgical parameters, and biochemical recurrence rate. Group 1 (n=34) was treated with RRP only, while Group 2 (n=19) underwent RRP along with NHT.

Results

There were no significant differences in clinical, operation-related and pathological factors between the two groups (p>0.05). There was also no significant difference in biochemical recurrence rate between the two groups at the last follow-up, although Group 2 tended to have a lower PCa recurrence rate than Group 1 and the initial prostate-specific antigen (PSA) level was significantly higher in Group 2 than Group 1 (p=0.0496).

Conclusion

The present single-surgeon case series study revealed a trend toward a lower rate of PCa recurrence in NHT+RRP treated patients compared to those treated with RRP alone, but this did not reach statistical significance, despite the fact that NHT+RRP patients exhibited higher serum PSA levels preoperatively. Prospective studies with a longer duration of observation and a greater number of patients would be helpful in evaluating NHT more definitively.     

Decisions about referrals for psychological therapies: a matched-patient qualitative study

Background

Psychological therapies are effective treatments for common mental health problems, but access is limited. GPs face difficult decisions as to whom to refer, but little is known about this decision-making process.

Aim

To explore GPs'' accounts of decisions to refer, or not refer, patients for psychological therapy.

Design of study

A qualitative study, using a matched-patient procedure.

Setting

General practices in two inner London boroughs.

Method

In semi-structured interviews, GPs were asked to compare and contrast five matched-patient pairs, consisting of patients who had been referred for psychological therapy paired with patients not referred. The interviews were analysed using a general thematic analysis.

Results

Fourteen GPs discussed 130 matched patients (65 patient pairs). Three main factors distinguished GPs'' accounts of the patients they referred compared with the matched patients they did not refer. These factors were: patient initiative in requesting or showing interest in referral; estimated capacity of the patient to benefit from psychological therapy; and the GP''s own capacity to help the patient in terms of skills, expertise, and time.

Conclusion

GPs gave accounts of themselves acting as rational decision makers, judging how effective they thought a referral would be based on a patient''s clinical presentation and motivation, compared with the GPs'' own ability to help.     

Biomechanical comparison of the four-strand cruciate and Strickland techniques in animal tendons

OBJECTIVE:

The objective of this study was to compare two four-strand techniques: the traditional Strickland and cruciate techniques.

METHODS:

Thirty-eight Achilles tendons were removed from 19 rabbits and were assigned to two groups based on suture technique (Group 1, Strickland suture; Group 2, cruciate repair). The sutured tendons were subjected to constant progressive distraction using a universal testing machine (Kratos®). Based on data from the instrument, which were synchronized with the visualized gap at the suture site and at the time of suture rupture, the following data were obtained: maximum load to rupture, maximum deformation or gap, time elapsed until failure, and stiffness.

RESULTS:

In the statistical analysis, the data were parametric and unpaired, and by Kolmogorov-Smirnov test, the sample distribution was normal. By Student''s t-test, there was no significant difference in any of the data: the cruciate repair sutures had slightly better mean stiffness, and the Strickland sutures had longer time-elapsed suture ruptures and higher average maximum deformation.

CONCLUSIONS:

The cruciate and Strickland techniques for flexor tendon sutures have similar mechanical characteristics in vitro.