Evidence for Efimov quantum states in an ultracold gas of caesium atoms.

Systems of three interacting particles are notorious for their complex physical behaviour. A landmark theoretical result in few-body quantum physics is Efimov's prediction of a universal set of bound trimer states appearing for three identical bosons with a resonant two-body interaction. Counterintuitively, these states even exist in the absence of a corresponding two-body bound state. Since the formulation of Efimov's problem in the context of nuclear physics 35 years ago, it has attracted great interest in many areas of physics. However, the observation of Efimov quantum states has remained an elusive goal. Here we report the observation of an Efimov resonance in an ultracold gas of caesium atoms. The resonance occurs in the range of large negative two-body scattering lengths, arising from the coupling of three free atoms to an Efimov trimer. Experimentally, we observe its signature as a giant three-body recombination loss when the strength of the two-body interaction is varied. We also detect a minimum in the recombination loss for positive scattering lengths, indicating destructive interference of decay pathways. Our results confirm central theoretical predictions of Efimov physics and represent a starting point with which to explore the universal properties of resonantly interacting few-body systems. While Feshbach resonances have provided the key to control quantum-mechanical interactions on the two-body level, Efimov resonances connect ultracold matter to the world of few-body quantum phenomena.

Grading choroidal neovascular membrane regression after strontium plaque radiotherapy; masked subjective evaluation vs planimetry.

PURPOSE: To analyze angiographic changes in choroidal neovascular membranes (CNVM) after strontium-plaque (90Sr) irradiation for exudative age-related macular degeneration (AMD) using masked measurement of the CNVM areas and a masked subjective comparison of CNVM size and leakage. METHODS: We studied the baseline, 3, 6, and 12-month angiograms of 19 eyes treated with 90Sr-plaque irradiation for exudative AMD. The area of CNVM-related hyperfluorescence was measured quantitatively, and the angiograms were subjectively evaluated by a masked grader. RESULTS: In 7 of the 19 eyes the CNVM-related hyperfluorescence was too scattered to be analyzed by planimetry but masked subjective grading correlated with the clinical response to irradiation. In the remaining 12 eyes, the CNVM decreased in size in 67% of the eyes and showed leakage in 67%. Planimetry and subjective assessment of the size and leakage of the CNVMs similarly reflected the regression after irradiation. CONCLUSIONS: CNVM size and leakage frequently diminish after 90Sr-plaque irradiation. Quantitative measurement of the CNVM areas, or a grading system based on masked subjective assessment, give similar results for evaluating these changes. Masked subjective grading can be used even in cases where the CNVM is too scattered to be outlined for planimetry.

Changing pattern of major lower limb amputations in Seinäjoki Central Hospital 1997-2000.

BACKGROUND AND AIMS: There is rather limited recent information on major amputations in Finland. Our objective was to describe the incidence of major lower limb amputations in a defined central hospital, the demographic characteristics of the amputees, diagnosis and situations leading to amputation, level of amputations and survival of the amputees after one year. MATERIAL AND METHODS: A retrospective study was undertaken on 156 patients with 169 lower limb major amputations from 1997 to 2000 at the Seinäjoki Central Hospital and Ahtäri District Hospital. RESULTS: The annual incidence of major amputations reduced from 29.5 to 15.2/100000 inhabitants. The mean age of the patients was 78.5 years but highest 80.1 in the year 2000. The reason for major amputation was chronic critical leg ischaemia with or without diabetes mellitus in 79.1% and acute ischaemia in 13.9%. The average below-knee (BK)/above-knee (AK) amputation ratio was 0.80 during the years 1997-1999 and the ratio was lowest 0.67 in year 2000. At the same year 2000 the amount of patients, whose condition was too poor for reconstructive surgery, was significantly higher than in 1997-1999. CONCLUSIONS: We suggest that BK/AK amputation ratio is decreasing in the future as the amputees tend more often to be institutionalized and immobile, and reconstruction is not an alternative and BK amputation is impossible or useless.

Visual function after strontium-90 plaque irradiation in patients with age-related subfoveal choroidal neovascularization.

PURPOSE: To report 2-year visual and angiographic results in eyes treated with strontium plaque irradiation for subfoveal choroidal neovascular membranes (CNVM) in age-related macular degeneration. METHODS: Twenty eyes with recent subfoveal CNVM were treated with local irradiation. The impact of the treatment on visual function was evaluated by visual acuity, contrast sensitivity and reading speed testing. RESULTS: At 12 months visual acuity had improved or remained the same in 9/ 20 eyes (45%). At 24 months visual acuity was stable in 5/18 eyes (28%). Eyes with signs of CNVM regression (13/18, 72%) lost a mean of 3.3 lines, but eyes with recurrent CNVM lost a mean of 5.1 lines of vision. The mean contrast sensitivity was better in the irradiated eyes than in the fellow eyes with late age-related macular degeneration at 24 months. Six of 17 irradiated eyes (35%) could read at least some words at 24 months. CONCLUSIONS: Visual function decreases in patients treated with strontium irradiation, but less in eyes showing regression of the CNVM than in eyes with further growth of the CNVM.

The use of confocal scanning laser tomography in the evaluation of retinal elevation in age-related macular degeneration.

OBJECTIVE: To evaluate the feasibility of using confocal scanning laser tomography in the analysis of macular topography in patients with subfoveal choroidal neovascularization associated with age-related macular degeneration (AMD) and to analyze quantitatively the changes in topography after local strontium-plaque radiation therapy. DESIGN: Prospective case series. PARTICIPANTS: A total of 16 eyes with subfoveal choroidal neovascular membranes (CNVM) treated with strontium-90 (90Sr)-plaque radiation therapy and 16 fellow eyes of 16 patients were examined. INTERVENTION: Confocal scanning laser analysis of macular surface topography before and after irradiation of the macula was performed. MAIN OUTCOME MEASURES: Parameters describing the height and volume of the retinal elevation in the macula were measured. RESULTS: The maximum height of the macular lesion at baseline was 0.25 mm (standard deviation [SD], 0.12 mm) in eyes showing regression of the CNVM during follow-up and 0.34 mm (SD, 0.19 mm) in eyes showing continued growth of the CNVM. During follow-up, a mean decrease in the maximum height of the macular lesion ranging from 0.03 to 0.10 mm occurred in eyes with regression of the CNVM, whereas the mean maximum height increased by 0.07 to 0.15 mm during follow-up visits in eyes with continued growth of the CNVM. All parameters describing the mean height and volume of the lesion also decreased significantly in patients showing angiographic regression, whereas they increased or remained unchanged in patients with continuous growth of the CNVM despite irradiation. The corresponding parameters also were higher in fellow eyes with untreated CNVM than in eyes without exudative AMD. CONCLUSIONS: Confocal scanning laser tomography can be used to monitor the amount of the change in neurosensory detachment in AMD. The parameters obtained by confocal scanning laser tomography correlate with CNVM perfusion after 90Sr-plaque radiation therapy. This technology is a useful tool for objective evaluation of morphologic change after institution of new therapeutic methods for the treatment of AMD.

Strontium plaque irradiation of subfoveal neovascular membranes in age-related macular degeneration.

PURPOSE: To determine the effect of focal strontium-90 plaque radiotherapy on subfoveal choroidal neovascularization in patients with age-related macular degeneration. METHODS: Twenty patients with age-related macular degeneration, presenting with a recent subfoveal neovascular membrane, were treated with local episcleral radiotherapy using a strontium-90 applicator. The applicator was applied to the sclera under the macular region and held there tightly for 54 min to obtain a dose of 15 Gy at a depth of 1.75 mm. The main parameters evaluated at follow-up after 3, 6 and 12 months were visual acuity and changes in fluorescein angiography. Twelve untreated patients with the same criteria were followed as controls. RESULTS: Early effects of radiation could be seen at 3 months, but became more obvious after follow-up for 6 and 12 months. At 6 months, regression of the choroidal neovascularization was detected in 14/19 patients (74%) as a decrease in the size of the lesion or as diminished leakage in late-phase fluorescein angiography. Likewise, in 14/19 patients (74%) at 12 months the neovascular membrane was partially or totally occluded. In all patients showing regression of the choroidal neovascular membrane, the neurosensory detachment had also dried. Visual acuity was unchanged (within 1 line) or improved in 11/20 (55%) and 9/20 (45%) treated patients after 6 and 12 months, respectively. In the controls, the choroidal neovascularization had increased in size in 9/12 patients (75%) at the last follow-up (mean 12.0 months). Visual acuity was unchanged in 3/12 patients (25%). CONCLUSION: Local low-energy beta irradiation with a strontium-90 applicator can induce regression of choroidal neovascularization. The effect of irradiation is seen as a decrease in the size of the choroidal neovascular membrane and disappearance of the neurosensory detachment and exudates.

Correlation between Octopus perimetry and fluorescein angiography after strontium-90 plaque brachytherapy for subfoveal exudative age related macular degeneration.

AIM: To evaluate the correlation between the central visual field and changes in fluorescein angiography and fundus photography in patients treated with strontium plaque radiotherapy for subfoveal exudative age related macular degeneration (AMD). METHODS: Octopus program 34 automated static perimetry, fluorescein angiography, and colour fundus photography were performed on 19 patients at baseline and at 12 months after strontium-90 plaque therapy. A schematic picture outlining the areas of hyperfluorescent neovascular membranes and subretinal blood was drawn of a projected 30 degrees fundus fluorescein angiogram. This drawing was superimposed on the size adjusted Octopus visual field. The changes in retinal sensitivity were calculated and related to angiographic changes. RESULTS: Three of the 19 patients had a reliability factor (RF) > 15% and were excluded from further analysis. In the remaining 16 patients the mean defect (MD) and loss variance (LV) values remained unchanged in patients showing regression of the choroidal neovascular membrane (CNVM) to irradiation at 12 months. MD was 7.7 (SD 1.7) at baseline and 7.6 (1.9) at 12 months (p = 0.86), and LV was 32.6 (13.9) at baseline and 32.4 (15.7) at 12 months (p = 0.94). However, in patients with progression of the CNVM at 12 months, both the MD and LV increased significantly during the 12 month follow up (MD from 7.3 (2.9) to 13.1 (3.6) (p = 0.05) and LV from 31.0 (22.9) to 71.8 (24.1) (p = 0.017)). When comparing the mean retinal sensitivity in the area of the primary CNVM (including classic, occult, and haemorrhagic components), the results were analogous: in patients with a regression of the CNVM after irradiation the mean sensitivity remained almost unchanged. It was 10.3 (6.4) dB at baseline and 9.4 (7.3) dB at 12 months (p = 0.58). In five out of 11 patients (45%) with regression of the CNVM, the mean retinal sensitivity even improved by 2.0-5.0 dB in the area of the original lesion during follow up. Instead, in patients showing progression of the CNVM at 12 months, there was a significant loss in mean retinal sensitivity--from 9.9 (4.6) dB at baseline to 1.0 (1.1) dB at 12 months (p = 0.019). The mean retinal sensitivity in the area of the irradiated but clinically normal retina during follow up was not significantly altered (21.5 dB at baseline, 19.7 dB at 12 months (p = 0.10)). CONCLUSIONS: Regression of subfoveal choroidal membranes in AMD after focal strontium irradiation is connected with stabilisation or even improvement of retinal sensitivity in central visual field measured by automated perimetry. Strontium plaque irradiation does not change the sensitivity in clinically normal paramacular retina during a 12 month follow up.

Auditing a nationwide vascular registry--the 4-year Finnvasc experience. Finnvasc Study Group.

OBJECTIVE: To assess the validity of a national vascular registry. MATERIALS AND METHODS: 17,465 vascular and endovascular procedures, immediate reoperations excluded, registered in the Finnvasc registry from 26 centres during the years 1991-1994. CHIEF OUTCOME MEASURES: Comparison of the number of registered procedures with hospital records, comparison of initial registrations with a random sample of re-registration and comparison of the 1-year local data input of one major centre to the same data input of the central unit. RESULTS: The rate of missing registrations was 19% ranging from 0-47%. The data of the re-registered forms were in agreement with the original data in 93% of all data points, the range being from 81-100%. There was a difference of 1.5% in the data between the major centre and the central unit. CONCLUSIONS: The Finnvasc registry makes it possible to audit vascular surgery nationally, although a potential limitation is centres with low registration rates.

Interferon alpha-2a in the treatment of exudative senile macular degeneration.

We performed a pilot study of 10 patients with the objective to determine the efficacy of interferon alpha-2a in the treatment of age-related macular degeneration with freshly diagnosed choroidal neovascular membrane. Interferon was given at a dose of 3 MIU/m2 three times a week for 8 weeks. Mean age of the patients was 74 years. In 3 patients we combined laser photocoagulation of extrafoveal part of the choroidal neovascular membrane to interferon therapy. The patients were followed up for 1 year after termination of interferon treatment. In 1 patient a visual improvement of two Snellen lines was noted, while in 7 patients visual acuity remained the same during the treatment (includes 3 patients treated with combined Krypton-laser photocoagulation). In 2 patients there was a decrease in acuity of one line. Six months later visual acuity had deteriorated in 7 patients and 1 year later all the patients had visual acuity < or = 20/200. We did not find any regression of choroidal neovascular membrane in fluorescein angiography in any of the patients during the treatment except the laser-treated area. At the 6-month follow-up there was still leakage or choroidal neovascular membrane growth in 6 patients. Combined interferon-laser therapy did not prove to be more effective in preventing the membrane growth. Side-effects included weakness, apathy, and fatigue in this elderly population. Our results indicate that treatment with 3 MIU/m2 interferon for 8 weeks is not an effective treatment for subfoveal choroidal neovascular membranes.

Barrett's esophagus after cardiomyotomy for esophageal achalasia.

Heller's myotomy for esophageal achalasia was performed on 64 patients in the 24 yr up to 1988. After follow-up averaging 13 yr, 46 patients were reexamined with endoscopy, biopsy, and manometry. Barrett's metaplasia of the distal esophagus was found in four patients 6, 13, 20, and 23 yr after the myotomy. These four also underwent ambulatory 24-h pH monitoring. They had the lowest distal esophageal sphincter pressures (1-5 mm Hg), and all four had symptoms of gastroesophageal reflux and pathologic pH values (< 4 in the distal esophagus for 32-62% of the total recording time). Because of heightened risk for the development of Barrett's metaplasia following cardiomyotomy for esophageal achalasia, with increased liability to carcinoma of the esophagus, regular endoscopic surveillance of these patients is advisable.

Suboptimal vision after vitreous surgery in diabetics.

Between 1979-1985, 105 diabetic patients underwent vitreous surgery for diabetic eye disease in one or both eyes. By spring 1991, 40 patients (38%) had died, and 36 (55%) of the living 65 patients had good or moderate vision (visual acuity, VA > or = 0.3 in the better eye), 13 (20%) had low vision (VA 0.05-0.25), and 16 (25%) were blind (VA < 0.05). For 19 of the 65 patients (29%) impaired vision was the main factor that limited independent activities. Of the 29 patients with suboptimal vision, 2 were employed, and none needed institutional care. Nine (31%) participated in all household activities, and 14 (48%) were able to read. Near vision aids were used by 14 of the 19 patients (74%) with ambulatory vision (VA > or = CF), but only 2 of them (11%) had accepted telescopic aids. Eight patients (28%) had a guide dog. In spite of vitreoretinal surgery, almost half of diabetic patients may end up with suboptimal vision, emphasizing the need for active visual rehabilitation.

Esophagocardiomyotomy for achalasia. Long-term clinical and endoscopic evaluation of transabdominal vs. transthoracic approach.

Modified Heller's myotomy for achalasia of the esophagus was performed via a left thoracotomy in 34 cases (group A) and via an upper midline abdominal incision in 30 (group B). There were no perioperative deaths. Complications arose in ten cases. After follow-up averaging 13 years (range 3-24 years) 4% of the group A patients reported dysphagia for solids, but none for liquids, and in group B the corresponding figures were 52% and 26%. Reflux symptoms were present in 30% of the group A and 60% of the group B cases, and the respective incidence of microscopic esophagitis was 30% and 43%. There were three esophageal strictures, all in group B, and three cases of Barrett's epithelium, all in group A. Because of the high incidence of esophagitis and its complications following esophagomyotomy for achalasia, yearly endoscopy with biopsy and brush cytology is recommended. When myotomy is performed, an antireflux operation should be added.

Pneumatic dilatation in oesophageal achalasia. Factors influencing results.

Pneumatic dilatation was performed for oesophageal achalasia in 19 consecutive patients without previous endoscopic or surgical treatment. There were no complications. Relief of symptoms was excellent or good in 11 cases during follow-up averaging 43 months. The outcome was better in patients older than 45 years than in younger patients. More than two repetitions of dilatation did not improve the results. Modified Heller's cardiomyotomy was performed on five patients with poor result after two to six dilatations. Pneumatic dilatation is safe and effective as initial treatment of oesophageal achalasia particularly in older patients, with cardiomyotomy reserved for those who do not respond to two dilatations.