Three-color dSTORM Imaging and Analysis of Recombination Foci in Mouse Spread Meiotic Nuclei

During the first meiotic prophase in mouse, repair of SPO11-induced DNA double-strand breaks (DSBs), facilitating homologous chromosome synapsis, is essential to successfully complete the first meiotic cell division. Recombinases RAD51 and DMC1 play an important role in homology search, but their mechanistic contribution to this process is not fully understood. Super-resolution, single-molecule imaging of RAD51 and DMC1 provides detailed information on recombinase accumulation on DSBs during meiotic prophase. Here, we present a detailed protocol of recombination foci analysis of three-color direct stochastic optical reconstruction microscopy (dSTORM) imaging of SYCP3, RAD51, and DMC1, fluorescently labeled by antibody staining in mouse spermatocytes. This protocol consists of sample preparation, data acquisition, pre-processing, and data analysis. The sample preparation procedure includes an updated version of the nuclear spreading of mouse testicular cells, followed by immunocytochemistry and the preparation steps for dSTORM imaging. Data acquisition consists of three-color dSTORM imaging, which is extensively described. The pre-processing that converts fluorescent signals to localization data also includes channel alignment and image reconstruction, after which regions of interest (ROIs) are identified based on RAD51 and/or DMC1 localization patterns. The data analysis steps then require processing of the fluorescent signal localization within these ROIs into discrete nanofoci, which can be further analyzed. This multistep approach enables the systematic investigation of spatial distributions of proteins associated with individual DSB sites and can be easily adapted for analyses of other foci-forming proteins. All computational scripts and software are freely accessible, making them available to a broad audience. Key features Preparation of spread nuclei, resulting in a flattened preparation with easy antibody-accessible chromatin-associated proteins on dSTORM-compatible coverslips. dSTORM analysis of immunofluorescent repair foci in meiotic prophase nuclei. Detailed descriptions of data acquisition, (pre-)processing, and nanofoci feature analysis applicable to all proteins that assemble in immunodetection as discrete foci. Graphical overview.

BRCA2 binding through a cryptic repeated motif to HSF2BP oligomers does not impact meiotic recombination

BRCA2 and its interactors are required for meiotic homologous recombination (HR) and fertility. Loss of HSF2BP, a BRCA2 interactor, disrupts HR during spermatogenesis. We test the model postulating that HSF2BP localizes BRCA2 to meiotic HR sites, by solving the crystal structure of the BRCA2 fragment in complex with dimeric armadillo domain (ARM) of HSF2BP and disrupting this interaction in a mouse model. This reveals a repeated 23 amino acid motif in BRCA2, each binding the same conserved surface of one ARM domain. In the complex, two BRCA2 fragments hold together two ARM dimers, through a large interface responsible for the nanomolar affinity - the strongest interaction involving BRCA2 measured so far. Deleting exon 12, encoding the first repeat, from mBrca2 disrupts BRCA2 binding to HSF2BP, but does not phenocopy HSF2BP loss. Thus, results herein suggest that the high-affinity oligomerization-inducing BRCA2-HSF2BP interaction is not required for RAD51 and DMC1 recombinase localization in meiotic HR.

High Resolution View on the Regulation of Recombinase Accumulation in Mammalian Meiosis

A distinguishing feature of meiotic DNA double-strand breaks (DSBs), compared to DSBs in somatic cells, is the fact that they are induced in a programmed and specifically orchestrated manner, which includes chromatin remodeling prior to DSB induction. In addition, the meiotic homologous recombination (HR) repair process that follows, is different from HR repair of accidental DSBs in somatic cells. For instance, meiotic HR involves preferred use of the homolog instead of the sister chromatid as a repair template and subsequent formation of crossovers and non-crossovers in a tightly regulated manner. An important outcome of this distinct repair pathway is the pairing of homologous chromosomes. Central to the initial steps in homology recognition during meiotic HR is the cooperation between the strand exchange proteins (recombinases) RAD51 and its meiosis-specific paralog DMC1. Despite our understanding of their enzymatic activity, details on the regulation of their assembly and subsequent molecular organization at meiotic DSBs in mammals have remained largely enigmatic. In this review, we summarize recent mouse data on recombinase regulation via meiosis-specific factors. Also, we reflect on bulk “omics” studies of initial meiotic DSB processing, compare these with studies using super-resolution microscopy in single cells, at single DSB sites, and explore the implications of these findings for our understanding of the molecular mechanisms underlying meiotic HR regulation.

Super-resolution imaging of RAD51 and DMC1 in DNA repair foci reveals dynamic distribution patterns in meiotic prophase

The recombinase RAD51, and its meiosis-specific paralog DMC1 localize at DNA double-strand break (DSB) sites in meiotic prophase. While both proteins are required during meiotic prophase, their spatial organization during meiotic DSB repair is not fully understood. Using super-resolution microscopy on mouse spermatocyte nuclei, we aimed to define their relative position at DSB foci, and how these vary in time. We show that a large fraction of meiotic DSB repair foci (38%) consisted of a single RAD51 nanofocus and a single DMC1 nanofocus (D1R1 configuration) that were partially overlapping with each other (average center-center distance around 70 nm). The vast majority of the rest of the foci had a similar large RAD51 and DMC1 nanofocus, but in combination with additional smaller nanofoci (D2R1, D1R2, D2R2, or DxRy configuration) at an average distance of around 250 nm. As prophase progressed, less D1R1 and more D2R1 foci were observed, where the large RAD51 nanofocus in the D2R1 foci elongated and gradually oriented towards the distant small DMC1 nanofocus. D1R2 foci frequency was relatively constant, and the single DMC1 nanofocus did not elongate, but was frequently observed between the two RAD51 nanofoci in early stages. D2R2 foci were rare (<10%) and nearest neighbour analyses also did not reveal cofoci formation between D1R1 foci. However, overall, foci localized nonrandomly along the SC, and the frequency of the distance distributions peaked at 800 nm, indicating interference and/or a preferred distance between two ends of a DSB. DMC1 nanofoci where somewhat further away from the axial or lateral elements of the synaptonemal complex (SC, connecting the chromosomal axes of homologs) compared to RAD51 nanofoci. In the absence of the transverse filament of the SC, early configurations were more prominent, and RAD51 nanofocus elongation occurred only transiently. This in-depth analysis of single cell landscapes of RAD51 and DMC1 accumulation patterns at DSB repair sites at super-resolution revealed the variability of foci composition, and defined functional consensus configurations that change over time.

Corneal astigmatism in Graves' ophthalmopathy

PURPOSE

To describe corneal astigmatism in patients under the age of 55 years with Graves' ophthalmopathy and to compare it to a control group.

METHODS

Retrospective, nonrandomized comparative observational case series. A total of 109 patients with inactive Graves' ophthalmopathy and 109 age- and gender-matched control individuals without Graves' ophthalmopathy were examined with manual corneal keratometry. In the Graves' patients, 52% had a CT scan available for review, and 41% underwent orbital, strabismus, and/or eyelid surgery with a follow-up of keratometry over a mean period of 1.7 years after surgery.

RESULTS

For the dioptres, there was a statistically significant difference between the Graves' and the control eyes at 3-3.25 dioptres in both eyes (t-test, right eyes, P=0.042; left eyes, P=0.041). For the meridians, the astigmatism was found to be greater at the meridians 95-100 degrees (t-test, P=0.044) and 105 degrees -110 degrees (t-test, P=0.017) in the right eyes only. In 10 (9%) Graves' patients, the astigmatism had caused newly acquired reduced visual acuity. Greater astigmatism in dioptres did not correlate with specific CT scan findings (chi(2)-test, df=2, P=0.187). Following orbital, strabismus, and eyelid surgery, the dioptres and meridians of the astigmatism did not change in 56 (68%) and 66 (81%) eyes, respectively.

CONCLUSIONS

Graves' ophthalmopathy may be associated with greater with-the-rule corneal astigmatism, which, overall, is not influenced by orbital, strabismus, or eyelid surgery. The astigmatism may possibly be caused by soft-tissue fibrosis in the superolateral orbital region.

Bony orbital development after early enucleation in humans

AIM

To analyse the extent of bony orbital volume reduction after enucleation in humans.

METHODS

Volumetric studies on bony orbital volumes based on three dimensional reconstructions acquired from high resolution computed tomograph (CT) scans were performed in 29 patients with acquired anophthalmia and four patients before enucleation (controls). Eight patients (follow up 25-52 years) were enucleated in childhood aged between 0.4 and 8 years (group I), 21 in adulthood aged between 15 and 53 years. Fifteen of these patients (group IIa) had long standing anophthalmia (follow up 7-53 years), six patients (group IIb) were enucleated 9 months to 4 years before CT.

RESULTS

Bony orbital volumes were reduced in all patients with long standing anophthalmia. The median percentage reduction in enucleated orbits was 7.0% in group I, 3.8% in group IIa, and 1.9% in group IIb. In patients with long standing anophthalmia (I and IIa) the reductions were statistically significantly different (p <0.01) from zero. There was some evidence of a correlation between orbital volume reduction and age at enucleation (rho = 0.36, p = 0.09, Spearman rank correlation coefficient) and a statistically significant correlation between volume reduction and time interval since enucleation (rho = -0.5, p = 0.003). Clinically none of the patients showed significant facial asymmetry.

CONCLUSIONS

These data provide strong evidence that enucleation both in children and adults is associated with a reduction of bony orbital volume and that this decrease in volume is associated with increasing time. However, the reduction is smaller than generally assumed and does not cause obvious facial asymmetry. It is more related to the time interval since enucleation than the age at enucleation, which makes a mechanism of volume adaptation more likely than just retardation of growth.

Dynamic magnetic resonance imaging of the levator palpebrae superioris muscle

The relationship between upper lid elevation (h) and shortening (s) of the levator palpebrae superioris muscle (LPS) has an influence on the dose-response relationship in ptosis surgery. In order to investigate the relationship between upper lid elevation and shortening of the LPS, parasagittal T1-weighted MR images of the orbit were obtained in healthy subjects with the eye in down- and upgaze. The position of the upper lid margin and the length of the LPS were measured in the images in down- and upgaze and the amount of h and s was determined. For a mean (+/- SD) vertical upper lid elevation of 15 +/- 1 mm, the mean (+/- SD) shortening of the LPS muscle was 21 +/- 3 mm (n = 4). The mean ratio of his was calculated to be 1:1.4, which means that the levator muscle must contract by 1.4 cm in order to achieve a lid elevation of 1 cm. Therefore, the force of the LPS which is necessary to lift the upper eyelid can be smaller than the lid-closing force. This strongly suggests a physiological mechanism which reduces the muscle force necessary for lifting the upper eyelid.

Is Whitnall's ligament responsible for the curved course of the levator palpebrae superioris muscle?

BACKGROUND AND PURPOSE

The levator palpebrae superioris (LPS) muscle courses anteriosuperiorly to culminate cranial to the posteriosuperior surface of the globe from where it courses anterioinferiorly to the trasal plate. Whitnall's superior transverse ligament (STL) has been suggested to suspend the LPS at its culmination. If this was the case, one would expect the STL to be located near the culmination of the LPS. In order to elucidate this functional aspect of the STL, the spatial relation of the STL of the LPS muscle is investigated in this study.

METHODS

Surface coil MRI in an oblique sagittal plane along the optic nerve was performed in 6 orbits from 3 human cadavers in which the STL was marked with synthetic material.

RESULTS

The MR images showed that in human cadaver specimens the STL is situated in the anterior descending portion of the LPS.

CONCLUSION

This result suggests that the STL does not suspend the LPS at its culmination and is therefore not responsible for the curved course of the muscle.

The intranasal ostium after external dacryocystorhinostomy and the internal opening of the lacrimal canaliculi

The purpose of this paper was to evaluate the appearance and location of the healed intranasal ostium and the internal aperture of the common canaliculus after uncomplicated external dacryocystorhinostomy (DCR). In 21 patients who underwent uncomplicated external DCR, the distances between the lacrimal puncta and the internal aperture of the common canaliculus were measured during surgery. The measurements were taken with a 1 mm diameter Bowman probe graded in millimeters. These measurements were recorded and considered the landmarks for the spatial localization of the internal aperture of the canaliculus. After surgery, under endoscopic control, the same method was used to measure the distance between the lacrimal puncta and the internal ostium, which was defined as the aperture through which it was possible to visualize the very first protrusion of the probe into the nose. The intra- and post-operative measurements were compared. Endoscopic photos of the healed endonasal ostium were also taken. The photos showed that when DCR procedures were not complicated by scarring or mucosal adhesions, the lacrimal sac became a depression perfectly integrated within the nasal mucosa. The scar at the site of junction between the nasal and the lacrimal sac mucosa appeared as a large-diameter pearl-like colored frame that surrounded the depression. In the context of the depression a small aperture, which presented a diameter of around 2 mm, could be easily visualized. The spatial location of this aperture corresponded to the internal aperture of the common canaliculus (p < 0.05).

Octreotide-scintigraphy is a disease-activity parameter in Graves' ophthalmopathy

OBJECTIVE

It is thought that immunosuppressive treatment of Graves' ophthalmopathy should be restricted to patients with active eye disease, but assessing disease activity is difficult. Octreotide scintigraphy has been claimed to differentiate active from inactive disease. Here we study the intraobserver variability and diagnostic accuracy of the quantitative measurement of orbital octreotide uptake.

PATIENTS AND DESIGN

Twenty-two consecutive patients with moderately severe ophthalmopathy were treated with retrobulbar radiotherapy. Pretreatment octreotide scintigraphic data were related to the response at six months after radiotherapy, using Receiving-Operator-Characteristic curves.

MEASUREMENTS

Octreotide uptake was measured at 4 and 24 h after i.v. injection of approximately 3 mCi (= 111 MBq; range 75-150 MBq) 111Indium-DTPA-Octreotide with a neuro-SPECT camera. Counts were measured in fixed regions-of-interest in 4 transversal slices of the orbit, the temporal and the occipital area. Measurements were done twice and intraobserver variability was analysed by coefficients of variations (CV). Uptake is expressed as orbital/background ratio. The nature of the temporal uptake was studied by matching an octreoscan with a technetium scan and MRI.

RESULTS

Intra-observer variability of measuring octreotide uptake was acceptable, and the coefficient of variation slightly better using the orbital/occipital ratio (11%), than the orbital/temporal ratio (16%). From matching studies it appears that the temporal uptake takes place, in part, in the parotid gland. The orbital/occipital ratio was used to predict the outcome of radiotherapy. Mean (+/- SD) uptake on the 4 h scan was higher in responders (2.2 +/- 0.66) than in nonresponders (1.7 +/- 0.39; P = 0.04). From the Receiving-Operator-Characteristic curve we determined a cut-off value of 1.85, which yielded a positive predictive value of 92% and a negative predictive value of 70%. The 24 h scan could not predict a response.

CONCLUSION

Quantitative measurement of orbital octreotide uptake is possible. Using the orbital/occipital ratio on the 4 h scan, the octreoscan seems useful in predicting response to subsequent radiotherapy. The 24 h scan seems not to be useful in predicting therapeutic outcome.

[Long-term results of secondary orbital implants]

BACKGROUND

Secondary orbital implants are used for the correction of the post-enucleation socket syndrome (PESS). This study evaluates retrospectively the post-operative course, complications, additional surgery, long-term cosmetic and functional results, and patient's satisfaction after secondary orbital implants.

PATIENTS

Nineteen out of 24 patients who underwent secondary baseball implant insertion between 1986 and 1989 for the correction of PESS were re-examined.

RESULTS

Five patients had complications, 11 patients (58%) further surgery. After a mean follow-up of 8.6 years, 17 patients (89%) showed findings better than preoperatively. Two patients were unchanged. The static overall impression, assessing particularly volume deficit and symmetry, using a scale of 1 to 5, was improved from 4.5 preoperatively to 2.5.

CONCLUSIONS

Secondary orbital implants improve symptoms of PESS and patient's satisfaction in a high proportion of cases also in the long term. Complications are not rare, and frequently more than one operation is necessary. There is no significant risk of long-term side effects and no reduction of the positive effect with time.

High-resolution MR imaging anatomy of the orbit. Correlation with comparative cryosectional anatomy

High resolution MR imaging of the orbit enables visualization of anatomic details in the orbit, including important blood vessels, muscles, nerves and connective tissue structures. The best resolution of anatomic details currently is obtained by using surface coils and T1-weighted spin echo sequences. Some examples of clinical applications demonstrate that a detailed knowledge of orbital imaging anatomy is a prerequisite for successful interpretation of clinical MR images. Additionally, this noninvasive diagnostic technique may be used for anatomical in vivo studies.

Three-dimensional imaging of congenital disorders involving the orbit

Three-dimensional imaging of the orbit and its adnexa provides an excellent topographic visualization of the deformity or tumor extent. This helps comprehension, communication, education, and documentation in the process of treating the patient. This article briefly describes the technique of three-dimensional imaging and classifies congenital orbital deformities which are extensively illustrated with relevant case material.

High-resolution magnetic resonance imaging of the orbital connective tissue system

A complex system of connective-tissue septa within the orbit has previously been described in serial histologic sections. The present study describes the anatomy of the orbital connective tissue system on high-resolution magnetic resonance (MR) images in vivo. Five volunteers aged 26 to 35 year underwent magnetic resonance imaging of the orbit on a 1 Tesla unit (Impact, Siemens, Germany). T1-weighted coronal images were obtained using a surface coil. Anatomical structures on the MR images were identified by comparison with corresponding histologic sections. On MR images of the anterior orbit, the levator aponeurosis, Lockwood ligament, transverse intermuscular ligament, common sheath, check ligaments, Tenon capsule, intermuscular septa, and palpebral ligaments can be seen. In the mid- and posterior orbit, the intermuscular orbital septa, especially the superolateral septum, the superior ophthalmic vein hammock, and septa of the radial connective tissue system are visualized. High-resolution magnetic resonance imaging is capable of delineating the major septa of the orbital connective tissue system.

The use of colour slides in the assessment of changes in soft-tissue involvement in Graves' ophthalmopathy

There is a need for more reliable and validated methods to assess the eye changes in Graves' disease. Such measurements are now available for the assessment of proptosis, eye muscle dysfunction, and optic nerve involvement. However, no validated objective measurement exists for NO SPECS class II signs. The present study compares the use of colour slides with clinical grading for assessing soft-tissue involvement. Forty-three patients were treated with retrobulbar irradiation. Pre-treatment, and 6 months post-treatment the severity of class II signs was graded from 0 to grade c in two ways; 1) Clinically, by two independent, experienced observers, who recorded their scores on the same day; 2) From colour slides, taken at the same visits, which were graded afterwards in one session independently by the same observers. Inter-observer agreement about clinical grading was low (Kappa 0.32), and was not improved by using the slides (Kappa 0.35). However, by using the clinical scores, the observers disagreed on treatment outcome in 21/43 patients (49%), whereas using the slides disagreement occurred in only 6/43 (14%, p < 0.01). It is concluded that the grading of soft-tissue involvement is highly subjective. However, the use of colour slides does provide a more reliable way to assess a treatment effect and should be used in clinical trials.

Anterior suspended flaps: a modified approach for external dacryocystorhinostomy

BACKGROUND/AIMS

External dacryocystorhinostomy (DCR) is a reliable but difficult surgical technique for the treatment of any obstruction of the lacrimal drainage system lying distal to the internal opening of the common canaliculus. In this prospective study, a simplified external DCR procedure and the results obtained on a series of 45 consecutive patients, in which traditional external DCR was indicated, are described.

METHODS

In this modified procedure only very large and mobile anterior flaps of the lacrimal sac and nasal mucosa are created. Thanks to the large size and the great motility the two flaps can be easily sutured. Two double armed 6/0 polyglycolic acid sutures are used to join the two flaps, to elevate them anteriorly in order to avoid adhesions with underlying tissues, and to approximate the deep planes of the wound. The mean operative time was measured.

RESULTS

At the end of follow up period (mean 17 months, range 14-24 months) all patients had no sign or symptoms of tearing and normal Jones I dye test. The mean operative time was 28.6 minutes (range 23-44 minutes).

CONCLUSION

We believe that our modified technique can be used to simplify and speed up traditional external DCR without decreasing its well known reliability.

High-resolution magnetic resonance imaging of the normal extraocular musculature

PURPOSE

Magnetic resonance imaging (MRI) of the extraocular muscles has attracted growing interest for the evaluation of complex motility disorders. However, little information is available on the high-resolution MRI anatomy of the normal extraocular muscles and their connective tissue system. The study describes the imaging anatomy of the recti and oblique muscles and the levator palpebrae superioris muscle.

METHODS

MRI of the orbit at 1 tesla was performed in four normal volunteers using a surface coil.

RESULTS

Many anatomical details such as Zinn's tendinous annulus, the trochlea, the superior oblique tendon, the intermuscular septa, the check ligaments, Lockwood's ligament and the common sheath between the superior rectus muscle and the levator muscle were visualised. A striking imaging feature was the curved path of both the recti muscles and the levator palpebrae muscle. The inferior oblique muscle also showed a marked curvature in the region of Lockwood's ligament.

CONCLUSIONS

High-resolution MRI is capable of demonstrating the anatomy of the extraocular musculature and parts of its connective tissue system. The curved path of the extraocular muscles can be explained by the configuration of the orbital connective tissue system which couples each extraocular muscle with the adjacent orbital wall. We discuss the clinical implications of our findings and review previous radiological studies regarding the functional anatomy of the extraocular muscles.

Quality of life in patients with Graves' ophthalmopathy is markedly decreased: measurement by the medical outcomes study instrument

To assess the impact of Graves' ophthalmopathy (GO) on quality of life using a general questionnaire, we performed a descriptive study on consecutive ophthalmopathy patients. We included 70 consecutive, euthyroid patients (age >18 years, 50 females, 20 males, mean +/- SD age 53 +/- 13 years) with varying degrees of severity of GO. General quality of life was assessed with the brief survey (24 questions) from the Medical Outcomes Study (MOS-24), and three subscales of the Sickness Impact Profile (SIP). In comparison with a large published reference group, low scores on the MOS-24 were found. Mean +/- SD scores (difference from reference group) were: physical functioning 58 +/- 31 (-28), role functioning 72 +/- 40 (-15), social functioning 78 +/- 25 (-14), mental health 67 +/- 18 (-10), health perceptions 46 +/- 22 (-26), and bodily pain 68 +/- 28 (-6). MOS-24 and SIP scores did not correlate with the duration, severity, or activity of the ophthalmopathy. In conclusion, we have shown that mild to moderately severe GO has a large influence on the quality of life of these patients. The negative impact on well-being seems not to be related to the usual clinical assessment. These results underscore the need for quality-of-life measurements in clinical trials.

Multidrug resistance-related proteins in primary choroidal melanomas and in vitro cell lines

PURPOSE

Metastatic uveal melanoma is strongly resistant to chemotherapy, and multidrug resistance (MDR) may be involved. To investigate the role of MDR, the presence of the MDR-associated proteins P-glycoprotein (Pgp), MRP, and lung resistance protein (LRP) was determined on primary choroidal melanomas and cell lines.

METHODS

A panel of primary choroidal melanomas was examined for the presence of MDR-associated proteins by immunohistochemical analysis. In cell lines established from four primary choroidal melanomas and one metastatic choroidal melanoma, the expression of MDR-associated proteins was determined with monoclonal antibodies in cytospin preparations and flow cytometry. In addition, the functional capacities of transporter proteins Pgp and MRP as adenosine triphosphate-driven efflux pumps were determined by measuring the cellular accumulation and efflux of the fluorescent dyes rhodamine 123 and calcein-AM, with and without the presence of specific pump inhibitors PSC833 and probenecid.

RESULTS

Low levels of Pgp and MRP were detected in most primary tumors and in some cell lines. Measurable transporter function of Pgp could be determined in cell line OCM-1. Lung-resistance protein was present in all primary tumors and cell lines and showed high expression levels.

CONCLUSIONS

This study revealed the involvement of LRP and at least a minor role of Pgp and MRP in chemoresistance of choroidal melanoma. Compared with cutaneous melanomas, uveal melanomas appear to express slightly higher levels of Pgp. These findings provide insights into the drug-resistant phenotype of this disease and can aid in the design of therapeutic protocols.

Brachytherapy in orbital tumors

PURPOSE

To evaluate whether the use of iridium-192 brachytherapy would reduce the incidence of complications noted with external beam radiation therapy in patients with orbital tumors.

METHODS AND MATERIALS

This study is a retrospective review of a clinical series of 25 patients with various orbital tumors treated with brachytherapy between 1988 and 1995.

RESULTS

Patients were observed for an average of 40 months (range, 16-88 months) during which one patient died of metastatic disease and 24 patients are alive with no evidence of disease. Recurrent disease was observed in four patients. In 3 patients, exenteration was necessary and in 22 patients, the eye was preserved. The visual acuities after therapy ranged from no light perception to 20/20 (average, 20/40).

CONCLUSIONS

Since brachytherapy has been used as an alternative to exenteration, the results of this treatment have been excellent in most patients. However, in advanced disease, external radiation therapy or even mutilating surgery still remains inevitable.

Clinical activity score as a guide in the management of patients with Graves' ophthalmopathy

OBJECTIVE

Approximately 35% of patients with Graves' ophthalmopathy do not respond to immunosuppressive treatment. A possible explanation for this finding is that only patients with active ophthalmopathy respond to immunosuppressive treatment, whereas patients with fibrotic end stage disease do not. To distinguish between these two groups and to predict the outcome of immunosuppressive treatment, we developed a clinical activity score (CAS) based on four of the five classical signs of inflammation and tested its efficacy in a double-blind, prospective study.

DESIGN, PATIENTS AND MEASUREMENTS

The CAS was determined by an opthalmologist before, on the day of, and after the start of either oral prednisone or retrobulbar irradiation in 43 patients with moderate to severe Graves' ophthalmopathy. The therapeutic outcome was determined by a second ophthalmologist unaware of the CAS stores given. Success of treatment was defined as an improvement in NOSPECS class or grade.

RESULTS

Responders (22) and non-responders (21) did not differ in age, sex, duration or severity of their Graves' ophthalmopathy. The pretreatment CAS, however, was significantly higher in responders than in non-responders. Twelve of 22 responders and three of 21 non-responders had a CAS > or = 4 (55% vs 14%; P < 0.01) [corrected]. Using this CAS cut-off point, the accuracy of CAS in predicting the therapeutic outcome was: specificity 86%, sensitivity 55%, positive predictive value 80%, negative predictive value 64%. Patients with a CAS > or = 4 had a similar duration of Graves' ophthalmopathy as patients with a CAS < 4.

CONCLUSIONS

The clinical activity score has a high predictive value for the outcome of immunosuppressive treatment in Graves' ophthalmopathy. Disease activity, and not disease duration, is the prime determinant of therapeutic outcome.

High resolution magnetic resonance imaging of neurovascular orbital anatomy

PURPOSE

This study describes the magnetic resonance imaging (MRI) anatomy of the blood vessels and nerves of the orbit to provide a morphological basis for the interpretation of clinical findings.

METHODS

Seven volunteers aged 29 to 54 years underwent high-resolution MRI of the orbit on a 1 Tesla unit (Impact, Siemens, Germany). T1-weighted oblique-sagittal, coronal, and axial images were obtained using a surface coil. Anatomic structures on the magnetic resonance images were identified by comparison with corresponding histologic sections of the orbit.

RESULTS

The ophthalmic artery and most of its branches (central retinal artery, posterior ciliary arteries, lacrimal artery, anterior and posterior ethmoidal arteries, supratrochlear artery, supraorbital artery, dorsal nasal artery) are visualized. The superior ophthalmic vein, the lacrimal vein, the medial ophthalmic vein, the inferior ophthalmic vein, the medial and lateral collateral veins, and the vorticose veins are also delineated. Furthermore, branches of the oculomotor nerve, the abducens nerve, the frontal nerve, the nasociliary nerve, the lacrimal nerve and the infraorbital nerve are identified in the magnetic resonance images.

CONCLUSION

High-resolution MRI is capable of delineating the orbital arteries, veins, and nerves. This is mainly based on two principles. First, blood vessels appear mostly dark on magnetic resonance images because of the signal void of flowing blood. Second, the bright background of the orbital fat on T1-weighted magnetic resonance images accounts for the good soft-tissue contrast in the orbit. With improved MRI technology and reduced imaging time, high-resolution-MRI may be applied routinely for diagnostic purposes.

Current status in the treatment of orbital myositis

PURPOSE

Orbital myositis is described as exquisitely sensitive to therapy with systemic corticosteroids. However, it may turn into a recurrent or chronic disease, requiring repeated courses or maintenance of corticotherapy that often is complicated with serious side effects. The authors conducted this study to evaluate their experience and the current status in the literature as to treatment of orbital myositis with corticosteroids and corticosteroid-sparing alternatives.

METHODS

The clinical records and computed tomography scans of patients with orbital myositis who presented at the Orbital Center Amsterdam between 1977 and 1991 were studied for the clinical course and therapeutic outcome. Recurrences were defined as a new attack of the same or another extraocular muscle as the primary affected, in the same or the other orbit.

RESULTS

The study group comprised 16 patients. All patients responded to initial treatment with oral corticosteroids (14/16) or nonsteroidal anti-inflammatory drugs (NSAID) (2/16). Of these 16 patients, 9 (56%) had 1 or more recurrences. Recurrences responded to repeated courses of corticosteroids, NSAID, or 20 Gy irradiation. Despite radiotherapy in six patients, recurrences continued to occur within a mean period of 2.7 years (range, 0.5 month-8.8 years). The mean follow-up after initial therapy in general was 9.7 years (range, 2.6-16.9 years), and after radiotherapy, in particular, was 7.4 years (range, 4.1-10.5 years).

CONCLUSIONS

Orbital myositis responds well to oral corticosteroids, but recurs in 50% of the cases. Based on a long-term follow-up of six patients who received irradiation of 20 Gy, radiotherapy appears ineffective in stopping recurrent orbital myositis.

Coronal approach for rehabilitative orbital decompression in Graves' ophthalmopathy

AIMS

To determine the effectiveness and safety of three wall orbital decompression by the coronal approach in Graves' ophthalmopathy.

METHODS

The records of 125 patients with Graves' ophthalmopathy, who had undergone three wall orbital decompression by coronal approach between April 1984 and October 1993, were studied retrospectively. Special attention was paid to proptosis reduction, changes in ocular motility, and complications.

RESULTS

The preoperative Hertel values ranged from 15 to 30 mm (mean 22.43 mm). The mean proptosis reduction was 4.34 mm (range 0-10 mm). Proptosis reduction in patients with preoperative Hertel values higher than 27 mm was significantly more than in patients with preoperative values between 25 and 27 mm (p < 0.05). This last group showed significantly more proptosis reduction than patients with preoperative Hertel values of 23 and 24 mm (p < 0.01). Postoperatively, 3.2% of the patients showed new diplopia in primary and/or reading position. In 4% of the patients with normal ocular motility preoperatively, diplopia in the extreme directions of gaze developed. In 4% of the patients, preoperative motility disturbances decreased or disappeared postoperatively.

CONCLUSION

Three wall orbital decompression by coronal approach is a safe and effective technique, to achieve proptosis reduction in patients with Graves' ophthalmopathy, with fewer complications than other techniques thus far described.

Idiopathic granulomatous orbital inflammation

PURPOSE

Granulomatous orbital inflammation may occur as an isolated condition of unknown origin. These idiopathic granulomatous lesions are believed to belong to the orbital pseudotumor group by some authors, whereas others consider them sarcoidosis limited to the orbit. The aim of this study is to define the clinicotherapeutic aspects of these lesions.

METHODS

The records of all patients with diagnosis of orbital pseudotumor and orbital sarcoidosis from the Orbital Center Amsterdam in the period between 1976 and 1994 were reviewed to define those with idiopathic granulomatous orbital inflammation. The authors studied the clinicotherapeutic aspects and histopathology of idiopathic granulomatous orbital inflammation by analysis of their own series and the literature.

RESULTS

Their study group encompassed seven patients with idiopathic granulomatous orbital inflammation. The mean follow-up was 9.5 years (range, 3.5-16.0 years). All had unilateral orbital presentation, with localization in the lacrimal gland in three patients. The lesions clinically presented with signs of mass effect or inflammation or both and were treated successfully with surgery, systemic corticosteroids, a combination of surgery and systemic corticosteroids, or systemic corticosteroids followed by irradiation. Histopathologic analysis showed a spectrum of granulomatous inflammation, admixed with nongranulomatous inflammation and fibrosis. There have been 30 similar cases described in the literature with comparable clinicotherapeutic characteristics.

CONCLUSIONS

Based on this study and the literature, it appears that idiopathic granulomatous orbital inflammation is more related to orbital pseudotumor than to orbital sarcoidosis.

Retrobulbar pressures measured during surgical decompression of the orbit

AIMS/BACKGROUND

In Graves' ophthalmopathy the increase in volume of intraocular muscles and fat will cause elevated intraorbital pressure. In order to investigate the pressure levels involved, intraorbital pressure, or retrobulbar pressure (RBP) was measured continuously in orbits of patients with Graves' ophthalmopathy during surgical decompression.

METHODS

Retrobulbar pressure was measured before and during surgical decompression using an intraorbitally applied pressure transducer.

RESULTS

In eight patients with dysthyroid optic neuropathy (DON) RBPs between 17 and 40 mm Hg were recorded. At the end of the surgical procedure the mean RBP was reduced from 28.7 mm Hg to 18.7 mm Hg, the decrease ranging from 8 to 12 mm Hg, which showed a high correlation with the starting pressures (p < 0.001). In two cases without DON, pressures were 11 and 9 mm Hg. Forces exerted by spatula manipulation usually resulted in a RBP level of more than 70 mm Hg.

CONCLUSIONS

This study shows that RBPs are markedly elevated in Graves' ophthalmopathy and that surgical decompression can result in a significant reduction in the intraorbital pressure. Optic nerve dysfunction in Graves' ophthalmopathy may not be caused exclusively by the direct pressure of swollen extraocular muscles upon the optic nerve, but also by a raised RBP. It is hypothesised that the damage inflicted upon the optic nerve can be caused in consequence by RBP induced incarceration of the nerve, compressed by surrounding periosteal lined orbital fat bulging posteriorly into the entrance of the optic canal.

The surgical management of lacrimal gland pseudotumors

PURPOSE

Lacrimal gland pseudotumors belong to the group of orbital pseudotumor. Systemic corticosteroids are advocated as the primary treatment of choice in orbital pseudotumor, but recurrent and refractory cases are commonly described. In this retrospective study, the authors evaluate alteerative treatment options such as surgical excision or debulking of lacrimal gland pseudotumors.

METHODS

The records of 26 patients referred to the Orbital Center of Amsterdam between 1976 and 1994 with a diagnosis of lacrimal gland pseudotumor were reviewed with special reference to computed tomography scans, histopathologic specimens (in 23 patients), treatment regimens, and final clinical outcome.

RESULTS

Histopathologic review showed 15 nonsclerosing (classic) and 8 sclerosing lacrimal gland pseudotumors. Initial treatment consisted of corticosteroids alone (9/26), surgery alone (7/26), a combination of surgery and irradiation (5/26), a combination of surgery and corticosteroids (4/26), or indomethacin alone (1/26). Surgery comprised tumor excision or tumor debulking. Of the patients treated with corticosteroids alone, 55% (5/9) responded initially but only 22% (2/9) obtained a cure. However, all patients treated with surgery combined with corticosteroids/irradiation (9/9), with surgery alone (7/7), or with indomethacin alone (1/1) responded well without recurrences. The main complication of therapy was dry eye syndrome, the incidence being highest in patients who received surgery of the palpebral lobe or irradiation. The mean follow-up was 4.9 years.

CONCLUSION

Surgical excision or debulking is a safe and effective treatment option in lacrimal gland pseudotumors, even in the histopathologic sclerosing variant.

Functional anatomy of the levator palpebrae superioris muscle and its connective tissue system

AIMS/BACKGROUND

The connective tissue system of the levator palpebrae superioris muscle (LPS) consists of the septa surrounding its muscle sheath, the superior transverse ligament (STL) commonly referred to as 'Whitnall's ligament' and the common sheath which is the fascia between the LPS and the superior rectus muscle (SRM). The anterior band-like component of the common sheath is called transverse superior fascial expansion (TSFE) of the SRM and LPS. It mainly extends from the connective tissue of the trochlea to the fascia of the lacrimal gland. A detailed description of the relation between the LPS and its connective tissue is presented. Furthermore, the course of the LPS in the orbit is described. The study was conducted to provide a morphological basis for biomechanical and clinical considerations regarding ptosis surgery.

METHODS

Postmortem dissections were performed in 16 orbits from eight cadavers. The microscopical anatomy was demonstrated in six formalin preserved orbits from six cadavers which had been sectioned in the frontal and sagittal plane and stained with haematoxylin and azophloxin. Surface coil magnetic resonance imaging in the sagittal and coronal plane was performed in five orbits from five normal volunteers using a T1 weighted spin echo sequence.

RESULTS

The STL and the TSFE surround the LPS to form a fascial sleeve around the muscle which has attachments to the medial and lateral orbital wall. The TSFE, which is thicker than the STL, blends with Tenon's capsule. The STL and the fascial sheath of the LPS muscle are suspended from the orbital roof by a framework of radial connective tissue septa. MR images show that the TSFE is located between the anterior third of the superior rectus muscle and the segment of the LPS muscle where it changes its course from upwards to downwards. In this area, the LPS reaches its highest point in the orbit (culmination point). The culmination point is located a few millimetres posterior to the equator and superior to the globe.

CONCLUSION

Whitnall's ligament can be considered to consist of two distinct parts--the TSFE inferior to the LPS and the STL superior to the LPS. Since the medial and lateral main attachments of Whitnall's ligament are situated inferior to the level of the culmination point of the LPS, the ligament itself is unlikely to suspend the levator muscle. However, a suspension of the LPS may be achieved by the radial connective tissue septa of the superior orbit. The TSFE in connection with the globe may have an additional supporting function. The elasticity of Whitnall's ligament and its connections with highly elastic structures including Tenon's capsule, may provide the morphological substrate for the previously proposed passive (that is, without orbicularis action) lowering of the lid during downward saccades.

What is orbital pseudotumor?

We have reviewed the literature in order to delineate the clinicopathologic definition of orbital pseudotumor, also called idiopathic nonspecific orbital inflammation. The clinical picture of orbital pseudotumor varies widely, with signs of mass effect, inflammation and/or infiltration. On computed tomography, orbital pseudotumor presents as a unilateral focal or diffuse mass. The histopathologic hallmark of orbital pseudotumor is a mixed inflammatory infiltrate with fibrosis of varying degree. Contrary to an old belief, orbital pseudotumor is not related to orbital reactive lymphoid hyperplasia (pseudolymphoma) and is not a lymphoid tumor. Atypical histopathologic findings of orbital pseudotumor include dominant sclerosis, granulomatous inflammation, vasculitis, and tissue eosinophilia. In the absence of systemic fibroinflammatory, granulomatous, and vasculitic disease, these atypical histopathologic patterns can be considered to represent subclasses of orbital pseudotumors rather then distinct entities. Clinical and prognostic characteristics of both histopathologically classical and atypical orbital pseudotumors appear to be heterogeneous. The etiology of orbital pseudotumor is unknown, but infection, autoimmune disorder, and aberrant wound healing have all been put forward as possibilities. In conclusion, orbital pseudotumor is one distinct disease albeit with many clinical and histopathologic guises.

Localized hypertrichosis associated with periorbital neurofibroma: clinical findings and differential diagnosis

BACKGROUND

Congenital localized hypertrichosis in the periorbital region is an uncommon finding. The authors report two patients with hypertrichosis and cutaneous hyperpigmentation overlying a periorbital neurofibroma.

METHODS

In addition to a complete ophthalmic and systemic examination, the patients underwent computed tomography of the head and biopsy of the tumor.

RESULTS

Case 1 previously had received a diagnosis of neurofibromatosis type I. On examination, hyperpigmentation, hypertrichosis, and swelling in the right supraorbital region were noted. A computed tomographic scan showed a tumor in the same region. The tumor was removed, and a plexiform neurofibroma was diagnosed. Case 2 was admitted with hyperpigmentation, hypertrichosis, and swelling of the left half of her face. Other signs of neurofibromatosis were absent. A computed tomographic scan showed a tumor, which was underlying the skin changes. Results of histologic examination of the biopsy specimen showed a plexiform neurofibroma.

CONCLUSION

Neurofibroma-associated hypertrichosis should be considered in the differential diagnosis of congenital localized hypertrichosis.

Are systemic corticosteroids useful in the management of orbital pseudotumors?

PURPOSE

Systemic corticosteroids are the established primary treatment for orbital pseudotumors, but patients with recurrent and refractory pseudotumors commonly are observed. In this retrospective study, the authors aimed to assess the value of corticosteroids in the management of orbital pseudotumor.

METHODS

The clinical notes, computed tomography scans, and histologic specimens of patients with orbital pseudotumor seen at the Orbital Center, Amsterdam, between 1976 and 1994 were analyzed with particular regard to the clinical and visual outcome. The patients were categorized according to the anatomic location of the pseudotumor within the orbit. Patients with pseudotumors restricted to the lacrimal gland or an extraocular muscle were excluded.

RESULTS

The authors studied 32 patients with orbital pseudotumor, 20 of whom had histopathologic confirmation. Twenty-seven of these 32 patients received systemic corticosteroids as an initial treatment. Of these 27 patients, 21 (78%) showed an initial response and 10 (37%) obtained a cure. After the initial response, 11 (52%) of the 21 patients recurred. Optic nerve involvement was present in 13 (41%) of the 32 patients, and all except 1 patient recovered with corticotherapy. The mean follow-up of therapy was 4.3 years (range, 5.3 months-21.5 years).

CONCLUSION

The authors found a moderate response, a high recurrence, and a low cure rate in patients treated with corticosteroids for orbital pseudotumor, and they therefore challenge the value of corticosteroids in both diagnosing and treating this condition. However, in patients with pseudotumor-induced optic neuropathy, corticosteroids remain of value.

Superior oblique luxation and trochlear luxation as new concepts in superior oblique muscle weakening surgery

PURPOSE

We used superior oblique luxation and trochlear luxation as new surgical procedures to treat acquired Brown's syndrome and superior oblique muscle overaction.

METHODS

We studied nine patients (11 eyes) who underwent trochlear surgery between 1988 and 1993. Four patients had acquired Brown's syndrome and five had superior oblique muscle overaction. In five patients (six eyes) the trochlea was incised to luxate the superior oblique tendon out of the trochlea. In four patients (five eyes) the trochlea was luxated out of its fossa via a periosteal approach without opening the trochlea itself.

RESULTS

The mean follow-up was 18 months (range, nine to 33 months). Postoperatively, eight patients showed subjective and objective improvement. One patient with painful traumatic acquired Brown's syndrome had no objective improvement but obtained relief of pain.

CONCLUSIONS

These new techniques are a successful alternative in the treatment of acquired Brown's syndrome and superior oblique muscle overaction.

Measuring eye movements in Graves ophthalmopathy

BACKGROUND

The current grading of class IV (extraocular muscle involvement) of the NO SPECS classification for Graves ophthalmopathy is subjective and, in practice, virtually limited to three grades (grade c rarely occurs). The subjectiveness results in a high degree of observer disagreement, as illustrated by kappa values of 0.48 to 0.64 for the agreement between the authors in grading of class IV changes in 13 patients.

METHODS

The authors investigated the significance of a quantitative approach in assessing eye motility and modified a hand perimeter to measure the monocular eye movements in degrees.

RESULTS

The mean maximal excursions in the four main directions of gaze, obtained with this device in 40 healthy control subjects (5 men and 5 women from each decade between 20 and 60 years of age), were as follows: elevation = 34 degrees, depression = 58 degrees, adduction = 48 degrees, and abduction = 46 degrees. The ductions showed an age-related decline. The intraobserver and interobserver variations were assessed in 12 and 18 patients with Graves ophthalmopathy, respectively, by calculating the coefficients of repeatability, which varied from 5 degrees to 8 degrees. The authors compared the current grading of NO SPECS class IV with quantitative measurements of elevation in 11 patients by calculating the kappa values for agreement. These were found to be 0.57 and 0.80, respectively.

CONCLUSIONS

The quantitative measurement of eye movements with a modified perimeter appears to be precise and reproducible. In addition, it should replace the current grading of the extraocular muscle movements of Graves ophthalmopathy patients in the NO SPECS classification, which is less reliable, as evidenced by a higher degree of observer disagreement.

Randomized double-blind trial of prednisone versus radiotherapy in Graves' ophthalmopathy

Corticosteroids are usually given for management of Graves' ophthalmopathy, but they have many and serious side-effects. By comparison, retrobulbar irradiation is well tolerated, although its efficacy has been evaluated only in uncontrolled studies. Therefore, we did a double-blind randomised trial, in which 28 patients with moderately severe Graves' ophthalmopathy were treated with a 3-month course of oral prednisone and sham irradiation, and 28 received retrobulbar irradiation (20 Gy) and placebo capsules. Therapeutic outcome, assessed twenty-four weeks after the start of treatment, was determined by the change in the highest NOSPECS class. A successful outcome was observed in 14 prednisone-treated and in 13 irradiated patients. Responders to treatment (but not nonresponders) in both groups showed improvements in total and subjective eye score and a decrease in eye-muscle volume. Response to either treatment was due largely to changes in soft-tissue involvement and eye-muscle motility. Mean elevation in responders to radiotherapy increased from 18.5 degrees (95% CI 14.8-22.2) at baseline to 21.8 degrees (18.6-25.0) at week twenty-four (p = 0.003), but did not change in prednisone responders. Side-effects were more frequent and severe during prednisone than during radiotherapy. Radiotherapy and oral prednisone appear to be equally effective as initial treatment in patients with moderately severe Graves' ophthalmopathy. In view of its better tolerability, radiotherapy should be considered the treatment of first choice.

Site-dependent distribution of macrophages in normal human extraocular muscles

PURPOSE

Clinical data indicate that extraocular muscles have different susceptibilities for some orbital immune disorders depending on their anatomic location. The resident immunocompetent cells may be important mediators in the local pathogenesis of such disorders so the distribution of these cells was studied in extraocular muscles obtained from normal human donors. For comparison skeletal muscles were studied.

METHODS

The cell distributions were analyzed quantitatively in cryostat cross-sections subjected to a two-step immunoperoxidase method using monoclonal antibodies against T cells, B cells, macrophages and several other markers for cell differentiation or activation. The macrophage distribution was analyzed in more detail using on-line semiautomatic image analysis equipment (VIDAS, Kontron, Elektronik GmbH, Eching, Germany).

RESULTS

Extraocular muscles contain numerous macrophages, fewer human leukocyte antigenD-related (HLA-DR) positive cells and T cells, whereas B cells are absent. The numeric density of all cell types, and macrophages in particular, is much higher in extraocular muscles than in skeletal muscles. In extraocular muscles the majority of T cells are positive for the CD8 antigen (suppressor/cytotoxic), in skeletal muscle CD4 positive T cells (helper) predominate.

CONCLUSIONS

Extraocular muscles contain many more CD8-positive cells and macrophages per square millimeter than skeletal muscles. Of all the cell types studied, only the macrophage distribution differs significantly among the normal extraocular muscles: the medial and inferior recti muscles contain about twice as many macrophages as the lateral rectus and superior oblique muscles. Their mean sizes (area) or shape distributions however, appear to be similar.

A new ultrasonographic method to detect disease activity and predict response to immunosuppressive treatment in Graves ophthalmopathy

PURPOSE

To determine whether the internal reflectivity of the eye muscles on A-mode ultrasonography serves as indicator for disease activity in Graves ophthalmopathy, thereby predicting response to immunosuppressive treatment.

METHODS

Eye muscle reflectivity, expressed as percentage of the initial scleral spike, was measured in the superior, medial, and lateral recti, and normal values were determined in 23 healthy controls. These were compared with values in 16 consecutive patients with untreated, moderately severe Graves ophthalmopathy. The accuracy of the measurement was assessed by calculating the intra- and interobserver coefficient of repeatability. Baseline eye muscle reflectivity in the 16 patients was correlated to the therapeutic outcome 24 weeks after start of immunosuppressive therapy. The response to treatment served as indicator for pretreatment disease activity.

RESULTS

Eye muscle reflectivity could be measured reliably, with an intraobserver coefficient of repeatability of 8.2% in controls and 10.2% in patients. Patients had lower reflectivity than controls (54.6 +/- 17.4% versus 70.7 +/- 6.6%; P < 0.001). Reflectivity in eye muscles with the lowest echogenicity was lower in responders than in nonresponders (25.8 +/- 8.4% versus 40.6 +/- 13.6%; P = 0.02). From the individual data, a cut-off value of 40% was derived, which appeared as an accurate predictor of outcome (positive predictive value 73%; 95% confidence interval 39%-94%).

CONCLUSIONS

Measuring eye muscle reflectivity in Graves ophthalmopathy appears to be a reliable new method to determine disease activity, with a promising accuracy in predicting therapeutic outcome of immunosuppressive treatment.

Site-dependent effects of experimental hypo- and hyperthyroidism on resident macrophages in extraocular muscles of rats: a quantitative immunohistochemical study

It has been suggested that the effects of dysthyroidism on resident immunocompetent cells of the extraocular muscles may play a role in the pathogenesis of Graves' ophthalmopathy. The distribution of such cells was therefore studied in extraocular muscles of rats that were made hyper- or hypothyroid by the oral administration of thyroxine or propylthiouracil respectively. Skeletal muscles were studied for comparison. The cell distributions were analysed in cryostat cross-sections subjected to a two-step immunoperoxidase method using well-characterized monoclonal antibodies against T cells, B cells, macrophages and MHC class II antigens. The extraocular muscles of control (euthyroid) rats contained numerous macrophages, fewer MHC-II positive cells and T cells and no B cells. Differences in the distribution of immunocompetent cells were found in control rats, between skeletal and extraocular muscles as well as within the various recti eye muscles. This particular tissue distribution resembles that previously reported for human extraocular and skeletal muscles. Quantitative analysis showed that experimental dysthyroidism only affected cell populations in the extraocular muscles. Significant effects on the number of macrophages were observed in the inferior rectus muscle of both hypo- and hyperthyroid rats, this was most pronounced in the orbital layer of the muscles. Both hyper- and hypothyroidism appear to affect local cell distributions in a tissue-specific manner. The presently observed site-dependent effects of dysthyroidism on local immunocompetent cell populations may have relevance for the differential involvement of muscular tissues in Graves' ophthalmopathy.

[Surgical rehabilitation in patients with Graves' ophthalmopathy; favorable results of orbital decompression via coronal approach]

Bilateral decompression of the orbit by a coronal approach was performed for cosmetic rehabilitation in 53 female patients with proptosis in the non-inflammatory stage after Graves' ophthalmopathy. Proptosis reduction averaged 5.9 mm Hertel value one year after surgery. All patients were satisfied with the cosmetic result obtained. Advantages of the technique used are: good access to all orbital walls facilitating adequate proptosis reduction; no visible scars after surgery; only very few complications. In our group there was no loss of visual acuity and the incidence of diplopia after surgery of only 4% is the lowest reported in the literature.

Metastatic tumors to the orbit--management and prognosis

In a retrospective study the records of 34 consecutive cases with tumors metastatic to the orbit were reviewed with special attention to the management and prognosis of these patients. The primary tumor site was the breast in 20 patients, prostate in 5, kidney in 2 and skin in 2. The remaining 5 patients had other primary tumour sites. The symptoms of orbital metastasis preceded the detection of the primary tumor in 8 cases (24%). Twenty patients died after a mean interval of 25 months following the diagnosis of the orbital metastasis. This study gives a summary of the clinical features of these patients. With improved methods of treatment it was possible to obtain a relief of orbital symptoms in 24 patients (71%). Although the life expectancy of these patients remains poor, treatment can result in symptomatic relief and in an improvement in the quality of life, which is the main goal in the management of these patients.

Soluble IL-2 receptor levels in patients with Graves' ophthalmopathy

In various autoimmune diseases circulating levels of soluble IL-2 receptor (sIL-2R) seem to be related to disease activity. Because reliable parameters of disease activity in Graves' ophthalmopathy are lacking, we measured sIL-2R levels in 47 patients with this disorder. The patients had Graves' disease, but no other immune-mediated diseases, had not yet received specific treatment for their ophthalmopathy and were euthyroid during the entire study period. Twenty-one of the 47 patients (45%) had sIL-2R values above the upper normal limit of 650 U/ml, as established in 20 healthy controls. There were no differences between patients with normal (median 469, range 280-644 U/ml) and elevated (median 946, range 678-1588 U/ml) sIL-2R levels regarding duration or severity of the eye disease (as assessed clinically from the total eye score). However, patients with severely enlarged eye muscles had higher sIL-2R values than patients with less severely enlarged eye muscles on CT scan. Patients with elevated sIL-2R tended to have a higher response rate (71%) to a 3-month course of prednisone, than those with normal levels (46%; P = 0.081). Since a successful outcome of prednisone treatment might be representative for disease activity, the elevated sIL-2R levels seem to reflect active inflammation. Although the practical relevance of this finding in individual patients is limited, it underscores the importance of cell-mediated immune responses in this thyroid-related eye disease.

Distribution of the nuclear thyroid-hormone receptor in extraocular and skeletal muscles

The correlation between the occurrence of Graves' ophthalmopathy and Graves' hyperthyroidism may indicate a role for tri-iodothyronine (T3) hormone in the pathogenesis of Graves' ophthalmopathy. In Graves' ophthalmopathy the recti eye muscles are greatly enlarged whereas skeletal muscles seem unaffected. The distribution of the nuclear T3 receptor was studied in normal human and rat eye and skeletal muscles with immunohistochemistry using mouse (monoclonal) antibodies, and by in-situ hybridization for the detection of mRNA encoding the T3-receptor protein. Nuclear staining with T3-receptor antibodies was found in all types of tissues studied. Cytoplasmic staining occurred predominantly in the muscle fibres of the orbital layer of the eye muscles and was generally absent or very low in skeletal muscle fibres and hepatocytes. Immunostaining could be inhibited by preabsorbing the antibodies with bacterially expressed T3-receptor protein, implying specificity. The presence of nuclear and cytoplasmic hormone-free T3 receptor sites was indicated after preincubation of sections with T3 hormone; T3-receptor immunostaining decreased and T3-hormone staining increased. In-situ hybridization clearly revealed the presence of alpha-1 and beta-1 forms of the T3-receptor mRNA in liver, skeletal muscles, and orbital and intermediate layers of the eye muscles. The data demonstrate the presence of T3 hormone-receptor molecules in the extraocular and skeletal muscles. The different susceptibilities of these muscles to Graves' hyperthyroidism may relate to the quantitative differences in T3 hormone-receptor distribution.

Recurrent hemangiopericytoma and brachytherapy

A 42-year-old woman had two recurrences following excision of a hemangiopericytoma of the left orbit. A third local excision was followed by postoperative brachytherapy (55 Gy in 100 hours). One year later there is no sign of recurrence and the side-effects are minimal.

Intradiploic epidermoid cysts of the bony orbit

Epidermoid cysts originating within the diploic space of the bony orbit are rare. The authors retrospectively studied four patients with an intradiploic epidermoid cyst of the orbital bones to investigate the clinical and the computed tomographic (CT) findings. The clinical presentation was dependent on the location of the slowly expanding epidermoid cyst. The sphenoid bone was involved in three patients and the frontal bone in one patient. Proptosis caused by intraorbital extension of the mass was the most common presenting sign. The findings on high-resolution CT scans appeared to be specific for intradiploic epidermoid cysts. The typical sclerotic margin, which is diagnostic of intradiploic epidermoid cysts, can be demonstrated by CT scans with a bone window setting.

Prosthesis motility with and without intraorbital implants in the anophthalmic socket

Ocular prosthesis motility was measured and compared in 15 patients with a primary baseball implant after enucleation of an eye, in 11 patients with a secondary baseball implant, in 12 patients with an Allen implant, and in 11 patients without any intraorbital implant. In all patients a noticeable lag of movement of the prosthetic eye was measured: in the extreme directions of gaze the excursions of the prosthesis were far less in comparison with the contralateral normal eye. For normal eye movement round the primary position of gaze, however, the prosthesis motility in the primary baseball and Allen implant group appeared to be sufficient to give a lifelike appearance. The average motility of the prostheses in these two groups did not differ. The motility in the secondary baseball group and in the group without an implant was evidently worse. In the last group the prosthesis motility was most impaired. We conclude that the insertion of an implant, even when inserted some time after the enucleation (a secondary implant), improves the motility of the prosthesis markedly. We recommend the primary baseball implant as the correction of choice after enucleation.