Genetic analysis of the compatibility between polymerase proteins from human and avian strains of influenza A viruses

In order to determine how efficiently the polymerase proteins derived from human and avian influenza A viruses can interact with each other in the context of a mammalian cell, a genetic system that allows the in vivo reconstitution of active ribonucleoproteins was used. The ability to achieve replication of a viral-like reporter RNA in COS-1 cells was examined with heterospecific mixtures of the core proteins (PB1, PB2, PA and NP) from two strains of human viruses (A/Puerto Rico/8/34 and A/Victoria/3/75), two strains of avian viruses (A/Mallard/NY/6750/78 and A/FPV/-Rostock/34), and a strain of avian origin (A/Hong Kong/156/97) that was isolated from the first human case of H5N1 influenza in Hong Kong in 1997. In accordance with published observations on reassortant viruses, PB2 amino acid 627 was identified as a major determinant of the replication efficiency of heterospecific complexes in COS-1 cells. Moreover, the results showed that replication of the viral-like reporter RNA was more efficient when PB2 and NP were both derived from the same avian or human virus or when PB1 was derived from an avian virus, whatever the origin of the other proteins. Furthermore, the PB1 and PB2 proteins from the A/Hong- Kong/156/97 virus exhibited intermediate properties with respect to the corresponding proteins from avian or human influenza viruses, suggesting that some molecular characteristics of PB1 and PB2 proteins might at least partially account for the ability of the A/Hong Kong/156/97 virus to replicate in humans.

Acute transient myopia induced by indapamide

PURPOSE

To report on a case of acute transient myopia associated with ciliochoroidal detachment induced by indapamide.

METHOD

Case report. Clinical examination, ultrasonography, and fluorescein angiography were performed during the acute phase of disease and convalescence.

RESULTS

After indapamide was discontinued, acute bilateral myopia, which was associated with anterior chamber shallowing and diffuse choroidal thickening, resolved spontaneously 8 days after onset. The initial angiography showed scattered islands of delayed fluorescein filling that disappeared without any permanent change by day 30.

CONCLUSION

Indapamide can induce spontaneously resolving transient myopia associated with diffuse choroidal thickening.

Long-term incidence of reopening of macular holes

OBJECTIVE

To report the incidence of macular hole reopening after initial successful surgery.

DESIGN

A noncomparative retrospective case series.

PARTICIPANTS

From a series of 137 consecutive cases of idiopathic macular holes operated on between August 1993 and May 1996, the authors analyzed the charts of 116 cases of successful surgery.

SETTING

A single university-based ophthalmology department.

INTERVENTION

Pars plana vitrectomy, posterior hyaloid peeling, fluid-air and air-gas exchange with a nonexpansile 17% C2F6 mixture followed by face-down positioning. Eighty-eight patients (64%) received autologous platelets as a biologic adjuvant. The anatomic success rate at the first postoperative month was 116 of 137 (85%). One hundred and six patients (91%) were followed up for more than 2 years.

MAIN OUTCOME MEASURE

Macular anatomic status.

RESULTS

Mean follow-up was 27 months. Eleven eyes of 11 patients (9.5%) had reopening of the macular hole. The mean period between hole surgery and reopening was 15.4 months (range, 8-29). In 8 of these 11 cases, reopening occurred after cataract extraction. In two cases, an epiretinal membrane was noted. In another case cystoid macular edema was present. The final anatomic success rate with one surgical procedure was 105 of 137 (77%). Eight reopened holes were reoperated on and all were anatomic successes at 1 month. However, four patients experienced a second reopening.

CONCLUSIONS

Macular hole reopening occurred in 9.5% of cases (11 of 116). The cause of reopening might have been any anatomic stress such as epiretinal membrane formation or macular edema. However, in most of our reopened cases, no definite cause was evident. Four patients experienced recurrent reopening.

The anatomic basis for the concept of lateralized femoral stems: a frontal plane radiographic study of the proximal femur

We determined the range of sizes for a system of monoblock femoral prostheses that would provide adequate (a term defined in the text) fill in the frontal plane and restore femoral offset and leg length. We performed an anatomic study, based on measurements in 200 anteroposterior pelvic radiographs. If diaphyseal filling implants are to be used, 9 sizes are sufficient to obtain excellent canal filling and restoration of femoral offset in >80% of cases, assuming that the level of neck osteotomy can vary over a 1-cm range. When using metaphyseal filling implants, only a limited adjustment can be obtained from the level of neck osteotomy. A system limited to 8 sizes approximates the anatomy of the femoral canal with satisfactory precision in 73% of cases. If such a system is provided with only a single neck shaft angle for each stem size, it does not allow restoration of the biomechanical center of the hip in >67% of cases. A system of 8 sizes of 1 neck/shaft angle and a 22-mm modular head restores the anatomy in only 49% of cases. Approximating the frontal anatomy of 85% of femora with an implant filling the metaphysis requires at least 15 sizes distributed in 3 metaphyseal configurations, each supplied with 2 different neck shalt angles.

Central retinal artery occlusion associated with head or neck pain revealing spontaneous internal carotid artery dissection

PURPOSE

To report two cases of head or neck pain and central retinal artery occlusion associated with spontaneous dissection of the ipsilateral internal carotid artery.

METHODS

Case reports.

RESULTS

We describe two cases of sudden visual loss caused by central retinal artery occlusion. Both cases were preceded by ipsilateral headaches or neck pain and tinnitus. The patient had no other neurological signs or history of trauma. In both cases, cerebral angiography revealed ipsilateral internal carotid artery dissection.

CONCLUSION

Ipsilateral headache or neck pain with tinnitus preceding central retinal artery occlusion is highly suggestive of internal carotid artery dissection. Early diagnosis and treatment may reduce the risk of hemispheric stroke.

Sclerochoroidal calcification associated with Gitelman syndrome

PURPOSE

To investigate sclerochoroidal calcification in a patient with Gitelman syndrome.

METHOD

Case report. Bilateral fundus abnormalities observed in a 58-year-old woman were documented with fluorescein angiography and tomodensitometry.

RESULTS

Symmetric yellow-white subretinal lesions were observed in the superotemporal midperiphery of the fundus of each eye. Tomodensitometry examination was consistent with calcium deposition. The medical history included Gitelman syndrome. Sclerochoroidal calcification probably resulted from the severe hypomagnesemia.

CONCLUSION

Gitelman syndrome may be a cause of sclerochoroidal calcification.

[Surgery of retinal detachment without giant tears, macular hole or advanced proliferative vitreoretinopathy]

PURPOSE

To evaluate surgical results in usual detachment cases.

MATERIAL AND METHODS

This retrospective study covered 704 non-referred cases treated by the same surgeon. A follow-up duration of at least 6 months was obtained for all the successful cases.

RESULTS

In 617 cases (87.6%) permanent reattachment was obtained with the first operation. The two main causes of initial failure were new or non-sealed breaks in 39 cases, 9 of them treated without a buckle, and postoperative PVR in 36 cases. After repeat surgery 48 additional cases were reattached, finally 665 cases (94.5%) were successfully treated. In all, postoperative PVR occurred in 39 cases, 22 of these were reoperated on, successfully for 16; thus PVR caused 23 of the 39 terminal failures. In 13 other failed cases there were no obvious unsealed break or severe postoperative PVR. A final visual acuity of 20/40 or more was attained in 443 cases.

CONCLUSION

PVR although infrequent (5.5%), was the main cause of failure. In 13 cases the reason for non reattachment remained uncertain, these failures may have involved an excessive vitreous traction and perhaps in this situation a vitrectomy with a wide angle viewing system might have been helpful.

Prevalence of macular pattern dystrophy in maternally inherited diabetes and deafness. GEDIAM Group

OBJECTIVE

To evaluate the prevalence of macular pattern dystrophy (MPD) in maternally inherited diabetes and deafness (MIDD), a new subtype of diabetes mellitus that cosegregates with a mutation of mitochondrial DNA (i.e., the substitution of guanine for adenine at position 3243 of leucine transfer RNA) and to report the clinical characteristics of MPD.

DESIGN

Prospective cohort study.

PARTICIPANTS

Forty-six patients from 29 families with an adenine-to-guanine mutation of mitochondrial DNA were recruited from a French collaborative multicenter study. Thirty-five patients had MIDD, 8 were asymptomatic children of MIDD patients, and 3 had MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes). The 33 MIDD patients with diabetes were matched for diabetes duration and gender with 33 patients with "common" type-2 diabetes to compare the prevalence of diabetic retinopathy (DR) in both series.

METHODS

All patients had a full ophthalmologic examination and fundus photographs.

MAIN OUTCOME MEASURES

The presence and severity of MPD and DR were assessed in each patient.

RESULTS

Thirty MIDD patients (85.7%) of 35 exhibited bilateral MPD characterized by linear pigmentation surrounding the macula and optic disc. In 24 of these 30 patients, visual acuity was 20/25 or more in both eyes. The prevalence of DR was 6% in MIDD patients with diabetes versus 15% for patients with common type-2 diabetes (a difference that was not significant, P = 0.23). The fundus of each of the eight asymptomatic children was normal. MPD was present in one of the three cases of MELAS.

CONCLUSION

The prevalence of MPD in MIDD is high. Its detection may be helpful for the diagnosis of this new subtype of diabetes, for which specific treatments may be proposed.

[Bilateral macular pseudocoloboma associated with chronic renal insufficiency in two sisters]

We report Meier's syndrome in two sisters, with combined macular pseudocoloboma and end-stage renal failure. The two sisters, aged 12 and 17 years, presented with a bilateral macular coloboma and slight myopic shift reducing visual acuity to 20/60 in one sibling and 20/100 in the other sibling. No other ocular abnormalities were present. The electroretinograms were normal. In both patients renal grafts were performed with good results. The mother and the 4 other siblings were unaffected. This observation underlines the need to check kidney function in case of bilateral pseudocoloboma.

Macular hole formation: new data provided by optical coherence tomography

OBJECTIVE

To establish the sequence of events leading from vitreofoveal traction to full-thickness macular hole formation.

METHODS

Both eyes of 76 patients with a full-thickness macular hole in at least 1 eye were examined by biomicroscopy and optical coherence tomography.

RESULTS

Sixty-one fellow eyes had a normal macula. Optical coherence tomograms showed central detachment of the posterior hyaloid over the posterior pole in 19 cases (31%) and a perifoveal hyaloid detachment not detected on biomicroscopy in 26 cases (42%). In the 4 impending macular holes, optical coherence tomography disclosed various degrees of intrafoveal split or cyst, with adherence of the posterior hyaloid to the foveal center and convex perifoveal detachment. In the 14 stage 2 holes, eccentric opening of the roof of the hole was observed, and in the 24 stage 3 holes, the posterior hyaloid was detached from the entire posterior pole.

CONCLUSIONS

In fellow eyes of eyes with macular holes posterior hyaloid detachment begins around the macula, but the hyaloid remains adherent to the foveolar center, indicating the action of anteroposterior forces. This results in an intraretinal split evolving into a cystic space, and then to the disruption of the outer retinal layer and the opening of the foveal floor, thus constituting a full-thickness macular hole.

[Cadaver study of acetabular cup mobility in the healthy hip and prosthesis by monopodal pressure simulation ]

PURPOSE OF THIS STUDY

The purpose of this study was to quantify relative displacement of anterior and posterior horn of the acetabulum lunate surface using Omega strain gauges while increasing loads were applied to the hip joint. Measurement were performed on fresh cadaver bones in unipodal stance using experimental method before and after socket's implantation.

MATERIAL AND METHODS

[corrected] Nine skeletons, from fresh non-embalmed cadavers, including pelvis, the three last lumbar vertebrae and both femurs were maintained in unipodal equilibrium using metallic cables for muscle passive simulation. Loads were applied up to 700 N. Specific extensometric Omega strain gauges were created and tested, with 5 mu of sensibility. Measurement of displacement between horns were studied on two sides of each pelvic before and after implantation of conventional and prototype cemented or press fit implants.

RESULTS

Among 81 loads on 18 acetabulum healthy and implanted, displacement was significant in 58 cases with a spacing of horn of 7 to 140 mu with average 31.1 mu and non significant in 25 cases. On healthy acetabulum, spacing was variable from 12 to 140 mu (average 43.2 mu) in 18 of 26 loads. On implanted acetabulum by different sockets, spacing was variable from 7 to 100 mu (average 27.4 mu) in 40 of 55 loads. Displacement was function of rotation hip, smaller in internal rotation and larger in external rotation. Spacing of horns was reduced in oversize sockets.

DISCUSSION

The data obtains by omega strain gauge suggest acetabular displacement is not univocal under load. There were a widening of the acetabular notch on load. This can be explained by the modification of primary incongruity of the two components of the hip joint because of acetabular deformation. Such results are in agreement with recently published data obtained about length of the transverse acetabular ligament.

Effect of autologous platelet concentrate in surgery for idiopathic macular hole: results of a multicenter, double-masked, randomized trial. Platelets in Macular Hole Surgery Group

OBJECTIVE

To evaluate prospectively the efficacy and safety of autologous platelet concentrate (APC) as an adjuvant in surgery for idiopathic macular hole.

DESIGN

Multicenter, double-masked, randomized clinical trial.

SETTING

Four university-based ophthalmology clinics.

PARTICIPANTS

One hundred ten patients with stage 3 or 4 idiopathic full-thickness macular holes of less than 3 years' duration were randomized (53 eyes to the platelet group and 57 eyes to the control group).

INTERVENTIONS

Standardized macular hole surgery versus surgery combined with injection of an APC. In all cases, the procedure consisted of three-port pars plana vitrectomy, posterior hyaloid separation, and nonexpansile fluid-gas exchange. After the fluid-gas exchange, patients were randomized to receive either injection of an APC or no adjunctive treatment. After surgery, patients were positioned face down for 12 days. Platelet counts showed that the concentrates contained a mean of 96.106 platelets (range, 82-102).

MAIN OUTCOME MEASURES

Anatomic and functional evaluations were performed at 1, 3, and 6 months after surgery in a double-masked fashion by an independent observer. The main outcome was reapposition of the edge of the macular hole 1 month after surgery. Secondary outcomes were anatomic status at 3 and 6 months, changes in Early Treatment Diabetic Retinopathy Study score, and complications.

RESULTS

One month after surgery, the anatomic success rate in the platelet group was 52 of 53 (98%; 95% confidence interval, 0.90-1.00) versus 47 of 57 (82%; 95% confidence interval, 0.70-0.91) in the control group (P = 0.009, Fisher's exact test; relative risk, 0.11; 95% confidence interval, 0.01-0.81). Visual acuity was not significantly different between the two groups at any timepoint. There were no complications specifically attributable to the platelet injection.

CONCLUSION

Injection of APC improved significantly the anatomic success rate of surgery for idiopathic macular holes of less than 3 years' duration, but postoperative visual acuity of the platelet group was not statistically different from the control group.

Visual outcome of surgery for epiretinal membranes with macular pseudoholes

OBJECTIVE

To evaluate the effect of macular pseudohole on visual results after epiretinal membrane (ERM) surgery.

DESIGN

Retrospective case-control study.

PARTICIPANTS

The postoperative results for 50 eyes with ERMs combined with pseudohole were compared with the results for a paired series of idiopathic ERMs without pseudohole operated on during the same period.

INTERVENTION

All patients underwent standard three-port pars plana vitrectomy, including core vitrectomy, and removal of the membrane.

MAIN OUTCOME MEASURES

Anatomic and functional evaluations were performed before and after surgery. Main outcome measures were postoperative visual acuity and the persistence or disappearance of the pseudohole.

RESULTS

For the patients with pseudohole, median preoperative visual acuity was 20/63 (range, 20/32-20/860) and median postoperative visual acuity was 20/40 (range, 20/20-20/860). Vision improved by 2 or more lines in 31 (62%) of 50 eyes. Forty eyes (80%) reached visual acuity of 20/50 or more. Pseudohole persisted in 22 eyes (44%) 3 months after surgery and in 15 eyes (30%) at 6 months. There was no difference in visual acuity, whether or not the pseudohole persisted. For the patients without pseudohole, median preoperative visual acuity was 20/63 (range, 20/32-20/860). Median postoperative visual acuity was 20/40 (range, 20/20-20/860). Vision improved by 2 or more lines in 37 eyes (74%). In 36 eyes (72%), it was 20/50 or more. Neither preoperative nor postoperative visual acuity differed significantly in the groups with and without pseudohole.

CONCLUSION

After surgery for idiopathic ERMs combined with pseudohole, visual outcome is good, and pseudohole has no adverse prognostic value. Pseudohole disappears inconstantly after surgery, but its persistence does not preclude good postoperative visual recovery.

vig-1, a new fish gene induced by the rhabdovirus glycoprotein, has a virus-induced homologue in humans and shares conserved motifs with the MoaA family

We used mRNA differential display methodology to analyze the shift of transcription profile induced by the fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), in rainbow trout leukocytes. We identified and characterized a new gene which is directly induced by VHSV. This VHSV-induced gene (vig-1) encodes a 348-amino-acid protein. vig-1 is highly expressed during the experimental disease in lymphoid organs of the infected fish. Intramuscular injection of a plasmid vector expressing the viral glycoprotein results in vig-1 expression, showing that the external virus protein is sufficient for the induction. vig-1 expression is also obtained by a rainbow trout interferon-like factor, indicating that vig-1 can be induced through different pathways. Moreover, vig-1 is homologous to a recently described human cytomegalovirus-induced gene. Accordingly, vig-1 activation may represent a new virus-induced activation pathway highly conserved in vertebrates. The deduced amino acid sequence of vig-1 is significantly related to sequences required for the biosynthesis of metal cofactors. This suggests that the function of vig-1 may be involved in the nonspecific virus-induced synthesis of enzymatic cofactors of the nitric oxide pathway.

Epiretinal membranes surrounding idiopathic macular holes

PURPOSE

To describe the features of the epiretinal membranes (ERMs) surrounding idiopathic macular holes.

METHODS

The charts of 83 consecutive patients (85 eyes) who underwent macular hole surgery with a systematic search for an ERM around the hole were reviewed. Visual acuity testing, fundus biomicroscopy, red free and blue filter fundus photographs, and fluorescein angiograms were performed before and after surgery. Eyes with and without ERM removal were compared.

RESULTS

An ERM was removed from 26 of 85 eyes (30.6%). ERMs were found more frequently in stage 4 than in stage 3 macular holes (76.9% versus 24.6%; P < 0.01). Holes had been present for longer in eyes with ERM than in those without (14.7 versus 8.6 months; P = 0.05). Fewer stage 3 holes with an ERM had an operculum than those without (P = 0.01). The outcome and complication rates were similar in eyes with an ERM and those without. Of the 24 ERMs detectable on blue filter fundus photographs, only 11 (45.6%) were visible on red free photographs.

CONCLUSION

We support the hypothesis that the presence of ERMs surrounding idiopathic macular holes is secondary to hole formation.

Functional assessment of macular hole surgery by scanning laser ophthalmoscopy

OBJECTIVE

This study aimed to evaluate more precisely the benefit of macular hole surgery.

DESIGN

The design was a prospective study of 40 eyes in 40 patients examined before and after surgery of full-thickness macular holes with a scanning laser ophthalmoscope (SLO).

PARTICIPANTS

Forty patients with full-thickness macular holes participated. Three of the holes were stage 2, 23 were stage 3, and 14 were stage 4.

INTERVENTION

The SLO examination consisted of macular imaging and assessment of macular function using tests produced by an acousto-optical modulator.

MAIN OUTCOME MEASURES

Preferred retinal locus (PRL) was determined, visual acuity was measured, and scotoma was detected by microscotometry and by the line test (modified Watzke-Allen test).

RESULTS

Anatomic success was achieved in 32 of 40 cases as assessed biomicroscopically. On SLO examination before surgery, macular holes were seen as a central bright round disc outlined by a thin dark edge surrounded by a dark ring and a less dark area with ill-defined limits. In all cases, the PRL was located on the upper edge of the hole, a scotoma was always detected inside the hole, and the line was seen as broken in 26 of 32 cases. After surgery, the hole closed completely in 25 of 32 eyes; it disappeared from 14 of these 25 eyes and was replaced by a dark or clear disc in 11. In the other seven successful cases, its size shrank and its edge flattened but remained faintly visible. The hole remained unchanged in eight cases. Eccentric PRL became central in 28 of 32 cases. The scotoma disappeared in 23 of 32 cases. The line was seen as continuous in 24 of 32 cases. Complete anatomic and functional successes were achieved in 19 of the 32 cases of macular hole closure.

CONCLUSION

The SLO examination allows accurate assessment of the anatomic and functional results of macular hole surgery. Various degrees of functional success were recorded, depending on the test used.

[Results of surgery of vitreomacular traction syndromes]

PURPOSE

The vitreomacular traction syndrome is a rare entity in which partial posterior vitreous detachment is combined with persistent macular adherence, thus causing macular traction. In most cases, an epimacular membrane is associated with this vitreomacular traction. We evaluate here the results of vitreous surgery for this syndrome.

METHODS

We reviewed 18 consecutive eyes that had undergone vitrectomy and posterior epiretinal membrane stripping, to define the visual results and complications of surgery for the vitreomacular traction syndrome. Minimum follow-up was 3 months.

RESULTS

Patients' average age was 63.5 years. All had evidence of cystic macular changes on biomicroscopic examination. Sixteen patients had an epiretinal membrane, and two, a full-thickness macular hole. Cystoid macular edema was present in 7 eyes on fluorescein angiography. The release of vitreomacular traction improved vision in 72% of eyes, with six patients obtaining 20/40 visual acuity or better. Complications of surgery included progression of nuclear sclerosis, and epiretinal membrane formation.

CONCLUSION

Vitrectomy for vitreomacular traction syndrome may improve visual acuity, but the visual prognosis remains poor.

[Acetabulum deformations after implantation of a cemented cup with or without metal-back component. An in vitro comparative study of monopodal load]

PURPOSE OF THE STUDY

The purpose of this study was to find a biomechanical explanation for a clinical failure of metal backed acetabular components. Periacetabular deformations were measured on fresh cadaver bones equipped with strain-gauge rosettes.

MATERIAL AND METHODS

Two skeletons, including pelvic bone, the two last lumbar vertebrae, and both femurs were maintained in unipodal equilibrium using metallic cables for muscle simulation. Loads were applied up to 700 N the approximating average body weight. A comparative study of periacetabular deformations was performed: right sides of each pelvic bone were implanted with conventional cemented implants, and left sides with metal backed cemented implants of same diameter and size.

RESULTS

Significant differences were noted: whereas no modification was brought by implantation of conventional cemented sockets, periacetabular deformations were reduced and smoothed after implantation of cemented metal backed implants. Such results are in agreement with recently published data obtained, using the finite element analysis method.

DISCUSSION

A study of pelvic ring and acetabular walls displacement was performed, but the authors couldn't find any clinical relevance to this biomechanical study.

[Treatment of aseptic acetabular loosening by reconstruction combining bone graft and Müller ring. Actuarial analysis over 11 years]

INTRODUCTION

One reason for the limited longevity of total hip replacement is the progressive bone loss resulting from iterative loosenings of acetabular components. In the early 80's was developed an experience at our institution for revision surgery of aseptically failed cemented acetabular components using a Müller ring. At that time, this device was used in combination with structural grafts. This appeared to us to be the safest method to address severe acetabular destructions. We are now able to report long term results.

MATERIAL AND METHODS

We carried out a retrospective study on 81 cemented acetabular revision arthroplasties performed at our institution between 1981 and 1991. In all cases, there was a segmental or an important cavitary roof defect. Reconstruction of the acetabulum was performed using a superior structural bone graft combined with a Müller ring. Results are given with a mean follow up of 8 years (5-14 years), except in the survivor analysis, in which all patients were included.

RESULTS

There was 15 iterative aseptic loosenings of the acetabular component (in which 5 repeated revisions). Using iterative aseptic loosening of the acetabular component revised or not as an end point, the 10 year cumulative survival rate (CSR) was 0.72 +/- 0.14 and the 11 year CSR was 0.55 +/- 0.24. The position of the hip biomechanical center, the polyethylene thickness, or the type of the superior defect (segmental or cavitary) were not found to influence significantly roentgenographic results.

DISCUSSION

Reconstruction of severely destroyed acetabuli using this method gave satisfactory results within the first decade. However, the hip function could not be reliably maintained over 10 years. Mechanical failures were related to resorption of weight bearing structural bone grafts. Aseptic iterative loosenings are often moderately symptomatic and yearly roentgenographic controls are necessary to detect late migrations. The lack of long term follow up may result in major bone loss, which can impair the conditions of iterative acetabular reconstructions.

Glycaemic control and development of retinopathy in type 2 diabetes mellitus: a longitudinal study

Relationships between glycaemic control, hypertension, and development of microangiopathy have been well documented in Type 1 (insulin-dependent) but not in Type 2 (non-insulin-dependent) diabetes mellitus. Therefore, we have investigated these relationships in a cohort of 64 Type 2 patients free of retinopathy (by angiofluorography), who were regularly followed until development of retinopathy or for at least 7 years as outpatients. Glycaemic control was assessed by 1 to 4 HbA1 determinations per year. Retinal status was monitored by annual angiofluorography. Nonproliferative retinopathy developed in 14 patients (cumulative incidence at 13 years: 29.8%) after a mean diabetes duration of 14.3+/-8.9 years (range 2-27). In multivariate analysis (Cox model), mean HbA1 during follow-up (p < 0.001), and hypertension at first examination (p = 0.09) were associated with the development of retinopathy, but age, sex, BMI, diabetes duration, smoking, and fasting blood glucose were not. The relative risk for developing retinopathy (RR) was 7.2 (IC 95%: 1.61-32.4) in patients with a mean HbA1 during follow-up above the median value of the cohort (8.3%) compared with patients with HbA1 during follow-up below this value. RR was 2.5 (IC 0.8-8) in patients with HbA1 at first examination above compared to below the median value (8.4%). RR was 3.0 (IC 0.9-10) in patients treated for hypertension at baseline compared to those without treatment. A sixfold increase in retinopathy prevalence was observed between patients with mean HbA1 in the highest or lowest quartile of mean HbA1 distribution during follow-up. This longitudinal study indicates a strong association between long-term glycaemic control and the development of diabetic retinopathy in Type 2 diabetes.

[Surgical treatment of post-traumatic macular holes]

BACKGROUND

Macular hole is a rare complication of blunt ocular trauma. Little is known about its spontaneous course and only a few operated cases have been reported.

METHOD

We present five cases of post-traumatic macular holes, 4 of which have been operated on.

RESULTS

In one case, the hole sealed spontaneously due to the formation of a slightly contractile epimacular membrane, and visual acuity improved from 0.1 to 0.5. The other four cases underwent vitrectomy, posterior hyaloid stripping, fluid-gas exchange and 12 days of postoperative positioning. In addition, two of these cases had autologous platelet injection. The macular hole closed in 3 of the 4 cases and vision improved in two.

CONCLUSION

Traumatic macular holes can close spontaneously, although this is rare. Usually, surgery with or without healing adjuvants is needed to close the hole. Visual results may be good if there is no damage to the subfoveal retinal pigment epithelium or to Bruch's membrane.

Late reopening of successfully treated macular holes

BACKGROUND

Most idiopathic macular holes can be closed by a surgical procedure combining vitrectomy, posterior hyaloid ablation, and fluid-gas exchange followed by postoperative positioning. Reopening of closed macular holes has been reported, but its frequency is not known. Here the incidence of reopening after successful macular hole surgery is reported.

METHODS

77 consecutive cases of idiopathic macular holes operated with autologous platelet injection between July 1993 and October 1995 were reviewed. The procedure consisted of three port vitrectomy, posterior hyaloid removal, nonexpansile fluid-gas exchange, and autologous platelet injection followed by face down positioning. The incidence of reopening was analysed in the cohort of the 72 anatomical successes.

RESULTS

Mean follow up was 12.3 months. The macular hole reopened in five eyes of five patients (five out of 72 patients, 6.9%), in four cases after cataract extraction. In four cases too, an epiretinal membrane was noted, either clinically or during reoperation, and fluorescein leakage in the macular area was present in two cases. Three of the five cases of reopening were reoperated and all three were anatomical successes.

CONCLUSION

Late macular hole reopening occurred in five out of 72 patient, and in four cases after cataract surgery. The presence of an epiretinal membrane around the hole in four of them suggested that tractional forces were responsible for the reopening. Reoperation, performed in three cases, again closed the macular holes.

Visual field loss after vitrectomy for full-thickness macular holes

PURPOSE

To report the results of a prospective study of the incidence of peripheral visual field loss after macular hole surgery.

METHODS

Prospectively, 30 eyes of 30 consecutive patients with full-thickness macular holes operated on between December 1995 and April 1996 had preoperative and postoperative Goldmann visual field tests. The surgical procedure consisted of three-port pars plana vitrectomy, posterior hyaloid removal, nonexpansile fluid-hexafluoroethane (C2F6) exchange, and, in 19 of 30 patients, autologous platelet injection, followed by face-down positioning.

RESULTS

Twenty-nine of these 30 cases were considered to be anatomic successes. Comparison of preoperative and postoperative visual fields disclosed that four patients (13%) had a peripheral scotoma, including one patient with stage 4 macular hole. Three other patients (10%) had a postoperative relative arcuate defect. Mean postoperative intraocular pressure was higher in the latter group. None of the patients complained of peripheral scotoma.

CONCLUSIONS

Overall, seven of 30 patients (23%) had a postoperative visual field defect. Two categories of scotomas were observed: peripheral and relative arcuate. The cause of peripheral visual field loss is unclear. Increased intraocular pressure may be the cause of relative arcuate scotomas.

Implementation of the Ottawa ankle rules in France. A multicenter randomized controlled trial

OBJECTIVES

To assess the impact of the implementation of the Ottawa ankle rules on radiography requests in French hospitals during a 5-month intervention period and the impact of using posters alone to sustain the effect of the rules during a 5-month postintervention period.

DESIGN

Multicenter randomized controlled trial preceded and followed by observational studies of radiological practices.

SETTING

The emergency departments of 5 Paris university teaching hospitals of the Assistance Publique-Hôpitaux de Paris.

PATIENTS

A total of 2218, 1911, and 851 patients-all aged 18 years and older-who were seen for acute ankle or midfoot injuries in emergency departments during preintervention, intervention, and postintervention periods, respectively.

INTERVENTION

Implementation of the Ottawa ankle rules by emergency department physicians in the intervention hospitals (using meetings, posters, pocket cards, and data forms). During the postintervention period, posters alone were used to sustain the intervention effect.

MAIN OUTCOME MEASURE

Percentage of patients for whom radiography was requested.

RESULTS

During the preintervention period, 98% and 98.5% of patients were referred for radiography in the intervention and control groups, respectively. During the intervention period, the mean proportions of patients referred for radiography by physicians was 78.9% in the intervention group and 99% in the control group (P=.03). Between preintervention and intervention periods, a relative reduction of 22.4% (95% confidence interval [CI], 19.8%-24.9%) in radiography requests was observed in the intervention group, while requests increased by 0.5% (95% CI, 0%-1.4%) in the control group. During the postintervention period, the proportion of radiography requests in the intervention hospitals was lower than the proportion observed in the preintervention period (83.1% vs 98%).

CONCLUSIONS

Implementation of the Ottawa ankle rules significantly reduced radiography requests in French hospitals. Using a minimal postintervention implementation strategy, the effect of this intervention decreased but persisted after it was discontinued.

Growth factors and diabetic retinopathy

Preretinal neovascularization and chronic retinal oedema are the two major sight-threatening complications that can occur during diabetic retinopathy. Ocular neovascularization is strongly associated with retinal ischaemia, and growth factors have been implicated in its pathogenesis. The ischaemic retina is assumed to secrete growth factors that stimulate residual vessels to proliferate. Interest has focused on basic fibroblast growth factor (bFGF), insulin-like growth factor-1 (IGF-1), platelet-derived growth factor (PDGF), transforming growth factor beta (TGF beta) and more recently vascular endothelial cell growth factor (VEGF). Histologic studies have demonstrated the presence of growth factor proteins and receptors and/or their mRNA, mainly VEGF, PDGF, and bFGF, in preretinal membranes of patients with proliferative diabetic retinopathy. Elevated intravitreal levels of IGF-1 and VEGF correlating with neovascular activity have been found in some patients. However, a direct causal relationship between ischaemia, growth factors and neovascularization has not been clearly demonstrated despite considerable research work. To date, the growth factor correlating most closely with neovascularization is VEGF. As many growth factors seem to be produced during the neovascular process, their specific inhibition probably will have limited effects. Laser photocoagulation of the retina has proved beneficial for regression of new vessels, probably through destruction of the ischaemic retina producing neovascular growth factors, and is currently the only treatment for proliferative diabetic retinopathy. Inhibition of IGF-1 by somatostatin analogs has produced unsatisfactory results. Other vascular inhibitors are currently being studied.

[Evaluating the results of surgery of choroidal neovessels]

BACKGROUND

Subfoveal choroidal neovascularization has usually a poor visual prognosis. Submacular surgery has been advocated as an alternative treatment. Visual results of this recent surgical technique is under current clinical evaluation.

METHODS

We retrospectively reviewed the charts of 16 eyes from 15 patients who underwent submacular surgery through a small retinotomy. Mean follow-up was 8 months (range from 5 to 88 weeks): group 1: submacular hemorrhages caused by age-related macular degeneration, 8 eyes; group 2: advanced subfoveal choroidal neovascularization in age-related macular degeneration, 3 eyes; group 3: young onset subfoveal choroidal neovascularization, 5 eyes.

RESULTS

Group 1: mean preoperative visual acuity was 0.024. Postoperative visual acuity increased for 5 eyes (63%) and decreased for 3 eyes (37%) (mean follow-up: 33 weeks). Two eyes had recurrent neovascularization. Group 2: mean preoperative visual acuity was 0.083. Postoperative visual acuity decreased for both eyes (mean follow-up: 58 weeks). Two eyes had recurrent neovascularization. Group 3: mean preoperative visual acuity was 0.082. Postoperative visual acuity increased for both eyes (mean follow-up: 26 weeks). Two eyes had recurrent neovascularization. In both groups, recurrent neovascularization was managed by laser photocoagulation.

CONCLUSIONS

Surgery of subfoveal choroidal neovascular membranes may stabilize or improve visual acuity in young patients. In subfoveal choroidal neovascularization due to age-related macular degeneration. this technique does not provide currently measurable visual improvement except in cases complicated by submacular hemorrhage. Results of future trials comparing surgery with spontaneous evolution or laser photocoagulation are necessary.

[Extracapsular extraction and posterior chamber implantation in diabetics. Prospective study of 198 eyes]

PURPOSE

Visual results and retinal changes in diabetic patients who underwent cataract surgery.

METHODS

In a prospective study we followed up 198 eyes of diabetic patients who underwent cataract surgery for at least six months postoperatively. Pre and postoperative retinal status were assessed by clinical examination and fluorescein angiography. Per and postoperative complications and the evolution of visual acuity were noted.

RESULTS

In 83.3% of eyes, visual acuity improved by two or more lines. In 59.6% of patients, visual acuity at six months was more than 6/15. The quality of visual outcome diminished with the severity of retinopathy, but in the most serious cases, lens extraction allowed fundus observation and treatment. Inflammatory complications, posterior capsule opacification and cystoid macular oedema were significantly more frequent in cases of preoperative diabetic retinopathy than in normal fundus. We observed few aggravations of the diabetic retinopathy, but underline the high frequency of cystoid macular edema in diabetic patients.

CONCLUSION

Visual results are good in diabetic patients with mild retinopathy and, in severe cases, surgery allows retinal examination and treatment.

[Retinectomies in the treatment of retinal detachments with vitreoretinal proliferation]

PURPOSE

To investigate the anatomical and functional results of retinectomy in the treatment of complex retinal detachment.

METHODS

We reviewed the files of 48 patients who underwent peripheral retinectomy of 90% or more for retinal detachment with anterior proliferative vitreoretinopathy stage A1 (6 cases), A2 (23 cases, A3 (11 cases) or A4 (8 cases). Retinotomy was performed when complete reattachment of the retina posterior to the buckling was not obtained despite careful dissection of the peripheral vitreoretinal contraction. Retinotomy was completed by excision of the anterior retinal flap. After perfluorocarbon liquid injection, laser retinopexy and perfluorocarbon-silicone exchange were performed.

RESULTS

Silicone oil was removed from 46 eyes (96%). The retina remained attached in 37 eyes (77%) with a visual acuity of 1/20 or more in 19 of them. Functional results did not correlate with the size of the retinectomy. The major complications were retraction of the retinectomy edge and recurrence of proliferative vitreoretinopathy, responsible for anatomic failure in 9 of the 11 cases. Hypotony (i.e. intraocular pressure of 5 mmHg or less) only occurred in 6 of the 37 successful cases.

CONCLUSION

Retinectomy is a useful surgical tool for eyes with advanced proliferative vitreoretinopathy when careful membrane dissection and encircling buckling seem to be insufficient to obtain retinal setting. Its success rate is good and leads to relatively few complaints.

[A propos of an unusual case of lumbar-pelvic dislocation in a suicidal jumper]

PURPOSE OF THE STUDY

We report a particular case of lombo-pelvic dislocation in a suicidal jumper, characterized by a distal sacral fracture associated with bilateral fractures of both iliac wings. To our knowledge, it has yet not been described.

MATERIAL AND METHODS

The patient was a 27 years old individual. On admission, he sustained the following injuries: hemodynamic shock with intraperitoneal bleeding due to disruption of the triangular ligament of the liver, which resolved with blood transfusions and did not require surgical treatment pelvic fractures initially identified as transverse fractures of both iliac wings, with bilateral avulsions of sciatic spines a compression fracture of the first lumbar vertebra without neurologic complication. In the intensive care unit, evolution was favorable. However, an incomplete cauda equina syndrome was noticed: the anal sphincter was flacid but perianal sensation to pinprick was conserved. An electromyogram showed that the latence of perineal reflexes was increased. The fracture and its displacement were recognized secondarily. A pelvic C.T. exhibited an increases in the antero-posterior dimension of the pelvic ring, due to a distal-displaced transverse sacral fracture. The proximal fragment of the sacrum remained attached to the iliac wing since sacro-iliac joints were intact, iliac wings had tilted forward, and the distal tip of the proximal sacral fragment was driven backward and inferiorly.

RESULTS

The patient was maintained in the supine position during 3 months. He then rapidly recovered normal function of his lower limbs. He had normal gait patterns and pelvic static. He did not complain of any pain. Finally, the neurological deficit disappeared and he regained full sexual function and complete control of micturition.

DISCUSSION

We think that this fracture should be considered as a variety of suicidal jumper's fracture described by Roy Camille et al. It has the same displacement as type 2 fracture in Roy Camille classification. In the emergency room, diagnosis is difficult, based on usual AP pelvic roentgenograms. A bilateral fracture of iliac wings in a suicidal jumper, especially if associated with bilateral sciatic spine avulsions, is an indication to a pelvic C.T.. A neurological perineal deficit should be ruled out. In our case, the perineal deficit can be attributed to the stretching of sacral roots resulting from a posterior displacement of the sacrum. The favorable evolution suggests that surgery may be not required, and there is no evidence in the literature that it would help neurological recovery. In distal fractures, the sacral canal is not narrowed, and a sacral laminectomy appears therefore not indicated.

CONCLUSION

We have described a particular type of transverse fracture of the pelvis, which, in our mind, should be put in the same category as type 2 transverse fractures of the sacrum described by Roy Camille and al, in the suicidal jumper. Since there is no compression of sacral roots into the sacral canal, prolonged bedrest is likely to be the better treatment.

[Surgical treatment of radiation-induced lesions of the hip in adults]

The authors report their experience in the surgical management of lesions of the adult hip following radiotherapy. The diagnosis of a hip problem occurring after pelvic radiotherapy for malignant tumors is made by clinical and radiological examination. The problems include femoral head necrosis, necrosis and/or fracture of the acetabulum, or involvement of the entire hip joint (radiation coxopathy). Fractures of the femoral neck have been described in the literature, but are now very rare following the routine use of external shields as protection during irradiation. Post-irradiation lesions are often bilateral 21%. They appear after a variable latency period of two to twenty years and they progress remorselessly. A diagnosis of simple radio necrosis can only be made after using radio isotope bone scanning, MRI or CT to exclude malignant disease as acetabular metastasis, and radio-induced sarcomas. Hemiarthroplasty is often followed by collapse of the acetabulum and should no longer be used. The treatment generally practised nowadays is a Total Hip Replacement (THR). We report a retrospective study of 71 hips in 56 patients treated, between 1970 and 1982, by the use of conventional cemented components. In 49 hips this was followed by a 52% incidence of acetabular loosening resulting from the poor quality of the irradiated bone which had become necrotic and porotic. Between 1983 and 1990, we modified the technique by regularly using reinforcing the acetabulum with a metallic ring fixed by long screws, (as used in revision surgery for THR). Bone grafts were also used in 9 cases. We had a 12% incidence of loosening in 22 hips with a mean follow-up of 40 months. There were also two post-operative infection which need removal of the prostheses. This emphasizes the risk of infection in this type of surgery and is probably increased by the associated lesions of the soft tissues (lymphoedema, radiodermitis). The authors wish to stress the poor prognosis of radiation lesions of the hip which often occur in patients who have otherwise recovered from their pelvic tumour. These radiation lesions have to be recognised and treated in a specific way. Our experience and the reports in the literature suggest that the generally used conventional THR gives uncertain results, and therefore we propose a THR employing metallic reinforcement of the acetabulum with or without any necessary bone grafts. It is vital to warn the patients that the results may not be as excellent as with THR for other types of hip disorders. When there is severe destruction of the acetabulum the choice between a THR combined with massive bone allograft, and a Girdlestone hip resection must be very carefully discussed with the patient. This latter "salvage" procedure may in any case become necessary if there are local and otherwise unmanageable problems.

Experimental study of periacetabular deformations before and after implantation of hip prostheses

This work is based upon an experimental simulation of one-legged stance, under loads close to the average body weight. Skeletons, harvested from fresh non-embalmed cadavers, included pelvis, two lumbar vertebrae, and both femurs. Periacetabular deformations were studied using tridirectional strain gauges before and after implantation of different types of acetabular prostheses in eight pelves: conventional polyethylene-cemented sockets, polyethylene sockets cemented into a metallic device, metal-backed cemented sockets, and hemispherical cementless press-fit cups with porous or hydroxyapatite coating. Strain measurements showed the persistence of important bone deformations at implant periphery. Mean values of normal periacetabular deformations were significantly reduced in two out of five acetabula implanted with cemented implants. In contrast, mean values of normal and circumferential deformations increased when polyethylene sockets were cemented into acetabular reinforcement devices, but this augmentation was significant in only one out of two cases. After implantation of cementless hemispherical metal-backed cups, periacetabular bone deformations also increased, but modifications were significant in a single case. Results are discussed according to the type of fixation (cemented or cementless), and to the difference in rigidity between implant and bone. There was no clear relation between implant stiffness and the magnitude of bone deformations.

Total hip replacement in irradiated hips. A retrospective study of 71 cases

We retrospectively reviewed 56 patients (71 hips) treated by total replacement for severe disability after pelvic irradiation. Symptoms were associated with various radiological lesions due to irradiation, including atraumatic femoral-neck fracture, osteonecrosis of the femoral head or of the acetabulum, and radiation osteitis of the whole pelvis. From 1970 to 1982 we used standard cemented components in 49 hips and had a high rate of acetabular loosening (52%) at a mean follow-up of 69 months. This was probably due to the mechanical insufficiency of irradiated periacetabular bone. From 1983 to 1990 we routinely used acetabular reinforcement rings. The rate of aseptic acetabular loosening in 22 hips at a mean follow-up of 40 months was 19%, but there were two septic loosenings emphasising the risk of infection in these patients. When total replacement is required for an irradiated hip, we recommend reinforcement of the acetabulum using a metallic ring, but there is still an increased risk of infection and in difficult cases such as severe acetabular destruction or soft-tissue or vascular injuries, a Girdlestone procedure may be indicated.

Total hip replacement in irradiated hips. A retrospective study of 71 cases

We retrospectively reviewed 56 patients (71 hips) treated by total replacement for severe disability after pelvic irradiation. Symptoms were associated with various radiological lesions due to irradiation, including atraumatic femoral-neck fracture, osteonecrosis of the femoral head or of the acetabulum, and radiation osteitis of the whole pelvis. From 1970 to 1982 we used standard cemented components in 49 hips and had a high rate of acetabular loosening (52%) at a mean follow-up of 69 months. This was probably due to the mechanical insufficiency of irradiated periacetabular bone. From 1983 to 1990 we routinely used acetabular reinforcement rings. The rate of aseptic acetabular loosening in 22 hips at a mean follow-up of 40 months was 19%, but there were two septic loosenings emphasising the risk of infection in these patients. When total replacement is required for an irradiated hip, we recommend reinforcement of the acetabulum using a metallic ring, but there is still an increased risk of infection and in difficult cases such as severe acetabular destruction or soft-tissue or vascular injuries, a Girdlestone procedure may be indicated.

Autologous platelet concentrate for the treatment of full-thickness macular holes

BACKGROUND

To improve the anatomic success rate in the surgery of full-thickness macular holes, we tested, in a prospective pilot study, the effects of autologous platelet concentrate deposited on the macula at the end of surgery.

METHODS

Two consecutive groups of patients were compared. Twenty eyes (group 1, mean symptom duration 11 months) were operated on with injection of an autologous platelet concentrate on the macula after fluid-gas exchange. Another 20 eyes (group 2, mean symptom duration 11 months) were subsequently operated on without autologous platelet concentrate. For all stage 3 holes, posterior hyaloid was detached en bloc at the level of the optic disc. The patient was left supine for 24 h after surgery, and then remained face down for 10 days.

RESULTS

In group 1, 19 cases were an anatomic success, i.e. there was flattening of the retina surrounding the hole and reattachment of the edge of the hole to the retinal pigment epithelium; in 9 cases the hole was even undetectable. Final visual acuity was 0.5 or more in 9 eyes, and 0.4 or more in 14. Visual acuity improved by two lines or more in 17 of the 19 successfully operated eyes. In group 2, only 13 cases were an anatomic success. The functional results for the successfully operated eyes were identical to those of group 1.

CONCLUSION

These results strongly suggested that autologous platelet concentrate could significantly improve the success rate in macular hole surgery and led us to begin a comparative, prospective, randomized trial.

Macular pattern dystrophy associated with a mutation of mitochondrial DNA

PURPOSE/METHODS

To establish association of a macular pattern dystrophy with maternally inherited diabetes and deafness, a new subtype of diabetes mellitus caused by a mutation of mitochondrial DNA (mtDNA). Two probands of two different families with maternally inherited diabetes and deafness were examined.

RESULTS/CONCLUSION

Both probands exhibited a macular pattern dystrophy, maternally inherited in one patient. The association of a macular pattern dystrophy with diabetes should lead to screening for a mutation of mtDNA.

[Autoclaved tumoral autografts. Apropos of 12 cases, 6 of which highly malignant]

Twelve patients presenting with a bone tumor were operated on using autoclaved bone autografts for reconstruction following carcinologic resection. According to the Enneking grading system, 6 were high malignancy tumors (3 osteosarcomas and 3 grade 2 chondrosarcomas), 4 were low grade tumors (1 paraosteal sarcoma, 1 chondrosarcoma, 1 secondary chondrosarcoma, 1 liposarcoma). One was a metastasis from a kidney tumor. The last patient had a femoral osteoid osteoma. Six local recurrences were responsible for 4 reoperations: 2 disarticulations and 2 iterative resections. With a 1-6 years range of follow-up (average follow-up 2.5 years), osseointegration of autoclaved grafts was studied. Fusion at the host/graft junction was roentgenographically observed. In three cases, proximal resorption of the humeral graft occurred. Five biopsies were obtained during reoperation after 1 year, which showed partial revascularization of autoclaved bone autografts. The authors conclude that autoclaved tumoral bone grafts, are reliable and discuss indications. They point out the main contraindication, represented by chemosensitive bone tumors, in which conservation of the removed tumor is necessary to quantify the response to chemotherapy.

Results of 203 total hip replacements using a smooth, cementless femoral component

We implanted 203 smooth-stemmed femoral components before January 1988. The femoral component used was anatomically shaped, fluted and made of titanium. Thirty-two hips were revised due to mid-thigh pain, and the femoral implant was found to be loose in all. In the 157 patients with a two-year follow-up, the Merle d'Aubigné and pain scores for completely cementless arthroplasties were similar to those for hybrid prostheses (cemented acetabular cup and cementless femoral stem). Of the 145 cases with two-year radiographic follow-up, 59 had extensive radiolucencies and 22 were unstable. The five-year cumulative survival rate was 77%. Implantation of this stem should be restricted to patients in whom cement fixation is contra-indicated.