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L Koornneef

Publications and source records attributed to L Koornneef.

At least 37 records · Page 2Linked to original sources
PubMed1997

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.

Adolescent↗
PubMed1997

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.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

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.

Acute Disease↗
PubMed1996

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.

Adult↗
PubMed1996

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.

Adolescent↗
PubMed1996

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.

Adolescent↗
PubMed1996

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.

Female↗
PubMed1996

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.

Adult↗
PubMed1995

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.

Adult↗
PubMed1994

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.

Adult↗
PubMed1993

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.

Administration, Oral↗
PubMed1993

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.

Adult↗
PubMed1993

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.

Adult↗
PubMed1992

[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.

Adult↗
PubMed1992

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.

Adult↗
PubMed1992

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.

Adult↗