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921.

Objective

The aim of the study was to compare the performance of several bedside neuropsychological tools for detection of HIV‐associated neurocognitive disorder (HAND) in antiretroviral drug‐exposed persons.

Methods

We analysed the relative performance of the HIV Dementia Scale (HDS), International HIV Dementia Scale (IHDS) and the Mini‐Mental Status Exam (MMSE) together with neuropsychological tests (Symbol‐Digit, Grooved Pegboard and Trail Making) in HIV‐1‐seronegative subjects (HIV?; n=13) and in HIV‐1‐seropositive subjects with HAND (HIV+HAND; n=13) and other neurological disorders (HIV+OND; n=20).

Results

Established neuropsychological tests consistently showed significantly poorer performance by HIV+HAND subjects compared with the other two groups. Similarly, the mean HDS and IHDS scores were lower in the HIV+HAND group compared with the other two groups (P<0.005) while the mean MMSE score did not show significant differences between the HIV+HAND and HIV+OND groups. Receiver operator characteristics curves generated from these data using predefined cut‐off scores revealed that the HDS, IHDS and MMSE displayed corresponding area under the curve values of 0.82, 0.74 and 0.48, respectively (P<0.006).

Conclusions

The present findings indicate that the MMSE is a weak tool for diagnosing HAND in this group of patients but the HDS and IHDS demonstrate better efficiencies, although cut‐off values for the HDS require reassessment in the era of effective antiretroviral therapy.
  相似文献   
922.
Hansen''s disease is a chronic infection caused by Mycobacterium leprae. Current therapy for this disease is with the WHO recommended Multi Drug Therapy (MDT) with DDS, rifampicin and clofazimine. Hyper Baric Oxygen Therapy (HBOT) has been used to treat many medical conditions including infections with a great deal of success. It''s efficacy on various species of mycobacteria and other bacteria have been studied in vitro and in vivo and it is found to be an effective antimicrobial agent under specified conditions. HBOT has been used to treat Hansen''s disease, including drug resistant lepromatous leprosy cases with good results. However there is a paucity of literature on this form of therapy. We have treated twenty cases of Hansen''s disease with HBOT prior to exhibiting MDT as per the WHO schedule. There has been a marked regression in skin signs especially decrease in erythema and flattening of raised lesions. This correlated well with the histopathological picture which showed a reduction in the inflammatory exudate.KEY WORDS: Hansen''s Disease, HBOT, Hyperbaric Oxygen, Leprosy, Therapy  相似文献   
923.

Objectives

As a first step in developing a protocol for multidimensional sialography using cone beam CT (CBCT), the objective of this study was to compare the effective radiation doses from sialography of the parotid and submandibular glands using plain radiography and CBCT.

Methods

The effective doses were calculated from dose measurements made at 25 selected locations in the head and neck of a radiation analogue dosimeter (RANDO) phantom, using International Commission on Radiological Protection 2007 tissue weighting factors.

Results

The effective dose (E) changed in relationship to changes in CBCT field of view (FOV), peak kilovoltage (kVp) and milliamperage (mA). Specifically, E decreased from a maximum of 932 μSv (30 cm FOV, 120 kVp, 15 mA) to 60 μSv (15 cm FOV, 80 kVp, 10 mA) for a parotid gland study and to 148 μSv (15 cm FOV, 80 kVp, 10 mA) for a submandibular study. The collective series of plain radiographs made during sialography of the parotid and submandibular glands yielded effective doses of 65 μSv and 156 μSv, respectively. The plain parotid gland series included one panoramic, two anterior–posterior skull and four lateral skull radiographs, whereas the submandibular gland series included one panoramic, one standard mandibular occlusal and four lateral skull radiographs.

Conclusion

The effective doses from CBCT examinations centred on the parotid and submandibular glands were similar to those calculated for plain radiograph sialography when a 15 cm FOV was chosen in combination with exposure conditions of 80 kVp and 10 mA.  相似文献   
924.
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926.
BACKGROUND: One of the primary difficulties in evaluating the effectiveness of lumbar fusion is that, with the exception of spondylolisthesis, specific diagnostic indications for surgery are poorly defined. Diagnostic specificity beyond the symptom of low back pain or the presence of lumbar degeneration needs to be delineated such that outcomes data can be effectively translated into clinical decision making or evidence-based guidelines. PURPOSE: The purpose of this study was to report on prospectively collected clinical outcome measures, stratified by diagnosis, among a series of patients with lumbar degenerative disease whose treatment included lumbar spine fusion. STUDY DESIGN: Demographics, diagnostic categorization, and clinical outcome measures were prospectively collected by six spine surgeons at a single tertiary spine center, as part of the surgeons' standard clinical practice. PATIENT SAMPLE: Four hundred and twenty-eight patients were enrolled in the study and complete 1- and 2-year Health-Related Quality of Life (HRQOL) data were available in 327 patients whose treatment included decompression and posterolateral lumbar fusion. OUTCOME MEASURES: The Oswestry Disability Index (ODI), Short Form-36 (SF-36), numeric rating scales for back pain and leg pain. METHODS: Preoperative diagnosis was classified, in the primary surgical cases, as disc pathology, spondylolisthesis, instability, stenosis, or scoliosis. In revision cases, the diagnosis was classified as nonunion, adjacent level degeneration, or postdiscectomy revision. Patient-reported outcomes at 1 and 2 years post-op were assessed based on diagnostic stratification. Statistical evaluation of clinical outcome was performed for both mean net change in outcome scores and the percentage of patients reaching a minimum clinically important difference (MCID) threshold for each outcome measure. RESULTS: Preoperative diagnosis was spondylolisthesis (n=80), scoliosis (n=17), disc pathology (n=33), instability (n=21), stenosis (n=46), postdiscectomy revision (n=67), adjacent level degeneration (n=40), or nonunion (n=23). Evaluation of 2-year post-op HRQOL measures by diagnostic subgroup revealed the most substantial improvement in ODI score for patients with spondylolisthesis (22.7 points) and scoliosis (21.2 points). Patients with the diagnosis of disc pathology (16.2 points), postdiscectomy revision (14.0 points), instability (12.7 points), stenosis (10.6 points), and adjacent level degeneration (9.5 points) demonstrated a progressively smaller magnitude of ODI improvement. The least ODI improvement at 2 years after surgery was seen in patients with nonunion of a prior fusion (5.5 points). The percentage of patients reaching MCID for ODI at 2 years post-op ranged from 71.0% in the spondylolisthesis subgroup to 34.8% in the nonunion subgroup. The greatest SF-36 physical component score improvement at 2-year follow-up was seen in patients with disc pathology (7.9 points) and spondylolisthesis (7.7 points), followed by scoliosis (6.6 points) and stenosis (6.5 points), instability (5.6 points), postdiscectomy revision (5.3 points) nonunion (3.1 points) and adjacent level degeneration (2.5 points). No significant changes from Year 1 to Year 2 were noted in any of the subgroups. For SF-36 physical component score, percentage of patients reaching MCID ranged from 63.6% in the disc pathology subgroup to 25% in the nonunion subgroup. CONCLUSIONS: This study supports the concept that added diagnostic specificity is a critical component in building an improved evidence base for lumbar fusion surgery. The magnitude of HRQOL improvement was not equal among diagnostic subgroups. The percentage of patients reaching an MCID level of improvement was also significantly influenced by diagnostic stratification. Without diagnostic specificity for entities beyond spondylolisthesis, the absence of well-defined study populations will continue to limit our ability to move toward evidence-based decision making.  相似文献   
927.
Marfan syndrome is a clinically and allelic heterogeneous, heritable connective tissue disorder with infrequently reported neuromuscular features. This study is the first to delineate these symptoms in a non-selected population. Neuromuscular involvement was evaluated in 10 Marfan patients through a standardized questionnaire, physical examination, nerve conduction study (NCS), needle electromyography (EMG), muscle ultrasound, laboratory investigation, and muscle biopsy. Existing neuroimages were screened for dural ectasia and spinal meningeal cysts. Twenty healthy controls with similar age distribution completed the questionnaire.
The results showed that various neuromuscular symptoms occur more frequently in the patients. Four older patients reported muscle weakness, five patients had a mild-to-moderate reduction in vibration sense, and all older patients mentioned mild functional impairments. NCS showed axonal polyneuropathy in four and EMG myopathic and neurogenic changes in all patients. Increased echo intensity and atrophy on muscle ultrasound was found in more than half of the patients. Muscle biopsies obtained in two patients showed myopathic changes in the older, female patient.
In conclusion, the majority of Marfan patients exhibited neuromuscular symptoms characterized as myopathy or polyneuropathy or both, and signs of lumbosacral radiculopathy, with symptoms being most pronounced in the older patients. Although meriting corroboration, these findings indicate a need to further the awareness of neuromuscular involvement in this population.  相似文献   
928.
929.
Despite the clinical importance of the question, a number of methodological issues have limited firm conclusions regarding the cognitive safety of deep brain stimulation (DBS) of the subthalamic nucleus (STN) in Parkinson's disease (PD). Amongst these issues, studies have generally failed to consider the postoperative changes that occur within individual patients. This study utilized reliable change indices (RCIs) derived from a PD sample to determine the frequency of clinically significant postoperative decline on a battery of neuropsychological measures. This approach addresses measurement reliability, potential practice effects, and disease progression. The proportion of patients experiencing clinically significant postoperative decline on measures of list learning and verbal fluency was greater than expected based on disease progression; however, the majority of patients (55%) did not experience a significant decline in performance on any of the cognitive tests administered, and only one experienced decline on more than one test. Therefore, the statistically significant declines on measures of list learning and verbal fluency observed in the sample as a whole were the result of clinically significant declines experienced by a minority of participants.  相似文献   
930.
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