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The paper describes the evaluation of magnetic resonance imaging (MRI) following osteoplastic flap procedure with fat obliteration. MRI scans performed in patients after surgery between 1st January 1986 and 31st December 1997 were evaluated. Outcome parameters were time-dependent changes in the distribution of adipose or connective tissue, development of necroses or oil cysts, recurrences, inflammatory complications, or mucocoeles. Eighty-six postoperative MRI scans from 51 operations were evaluated. In 19 cases between two and five MRI scans were available. Time between surgery and the last MRI scan was 24.1 months on average. We found five mucocoeles. The amount of adipose tissue depictable on the last scan was less than 20% in the majority of cases (53%) and more than 60% in only 18% of cases. Statistical tests and modelling showed a significant decrease of adipose tissue with time, with a median half-life of 15.4 months in a subgroup with at least two MRIs. MRI is at times the most valuable diagnostic tool after frontal sinus obliteration using adipose tissue. The method has some limitations with regard to detection of small (recurrences of) mucocoeles and differentiation between vital adipose tissue and fat necroses in the form of oil cysts. In difficult cases long-term MRI follow-up is necessary for definitive evaluation.

Surgery after pre-operative embolization has become the main treatment modality in angiofibroma therapy. As surgical planning is based on precise pre-operative tumour evaluation, knowledge of the characteristic growth patterns is of great interest. Analysis of tumour extension and blood supply, as well as methods of controlling intra-operative bleeding, help in determining the appropriate surgical approach. Though benign, angiofibroma demonstrates a locally aggressive nature. This fibrovascular tumour is characterised by typical radiological findings and by predictable growth patterns. The tumour extension and blood supply can be accurately determined by CT, MR imaging and angiography. With classic radiological findings, no pre-operative biopsy is necessary in most angiofibromas. Advances in radiological imaging have contributed to improved surgical planning and tumour resection. The surgeon is able to select the least traumatic approach with secure haemostatic control, which is also critical for avoiding the disturbance of facial skeletal growth in this group of young patients. Embolization, pre-operative autologous donation and the cell saver system for immediate retransfusion of the collected blood after filtration, are important tools for dealing with blood loss in angiofibroma surgery as they minimize homologous blood transfusion.

A new hybrid humidity sensor comprising a conventional capacitance humidity sensor and a planar heating element is described. Owing to its short response time of only a few milliseconds, its great measuring accuracy, large measuring range, and simplicity in handling, the sensor is suitable for measuring water vapour partial pressure in gases with rapidly changing flow and direction, e.g. in ventilated patients in the fields of anaesthesia and intensive care medicine. The small dimensions permit measurements at almost any location within the ventilation system.

BACKGROUND The osteoplastic flap procedure with fat obliteration has been hailed as the gold standard of definitive frontal sinus procedures for chronic inflammatory disease. The value of magnetic resonance imaging (MRI) in postoperative follow-up has not yet been sufficiently examined. METHODS All postoperative MRI scans performed in patients undergoing surgery between January 1, 1986, and December 31, 1996 were evaluated. The outcome parameters were time-dependent changes in the distribution of fatty or connective tissue and development of necroses or oil cysts, as well as recurrences, inflammatory complications, or mucoceles. RESULTS Sixty-eight operations were performed in the specified period and a total of 73 postoperative MRI scans from 45 operations were available for evaluation. In 16 cases, between two and five MRI scans were available. The individual time between surgery and the last MRI scan ranged from two weeks to 130 months with an average of 30.1 months. We found four mucoceles 34, 49, 106, and 130 months, respectively. Three of the mucoceles were diagnosed on the first postoperative MRI scan. In the fourth case the mucocele had not been seen on the previous scan. The amount of adipose tissue depictable on the last scan was less than 20% in the majority of cases (58%) and more than 60% in only 18% of cases, although in the latter group the time between surgery and MRI was less than 7 months in half the cases. CONCLUSIONS MRI is the most valuable diagnostic tool after frontal sinus obliteration using adipose tissue. Despite the good soft tissue differentiation, the method has some limitations with regard to detection of small recurrent mucoceles and differentiation between vital adipose tissue and fat necrosis in the form of oil cysts. In these difficult cases, long-term MRI follow-up is necessary for definitive evaluation. We therefore recommend MRI 1, 2, and 5 years after osteoplastic frontal sinus surgery with obliteration.

A series of substituted tetrahydropyrrolo[2,1-b]oxazol-5(6H)-ones and tetrahydropyrrolo[2,1-b]thiazol-5(6H)-ones was synthesized from amino alcohols or amino thiols and keto acids. A pharmacological model based on the results obtained with these compounds led to the synthesis and evaluation of a series of isoxazoles and other monocyclic compounds. These were evaluated for their ability to enhance glucose utilization in cultured L6 myocytes. The in vivo hypoglycemic efficacy and potency of these compounds were evaluated in a model of type 2 diabetes mellitus (non-insulin-dependent diabetes mellitus), the ob/ob mouse. 25a(2S) (SDZ PGU 693) was selected for further pharmacological studies.

BACKGROUND The operative treatment and radiation therapy of jugulotympanic paragangliomas (JTP) are still a matter of controversial discussion. In spite of various improvements during the last 50 years, selecting the appropriate treatment modality (surgery, radiation, or observation) is still a challenge. PATIENTS During a 16-year period, 44 patients with 45 JTP (10 at level A/B and 35 at level C/D according to Fisch) were seen at the ENT-department in Fulda. Forty-one cases were treated surgically. RESULTS Complete resection was possible for level A/B in 100% of the patients (n = 10). Residual tumor was demonstrated for level C in 23% of the patients (5/22) and for level D in 40% (4/10) with a median follow-up time of 69 months. In two cases residual tumor was treated by radiation. Six patients with residual paraganglioma tissue were maintained under observation without any evidence of tumor progression (median follow-up time 39 months). We report one death after the attempt to resect a large residual paraganglioma that had already caused brain stem compression. A sufficient duraplasty could not be achieved following radiation therapy. CONCLUSIONS Complete tumor resection of jugulotympanic paragangliomas of levels A and B is often possible without injury to the cranial nerves. Extensive tumors present difficulties in complete tumor resection and increase the risk of cranial nerve injuries. Advanced paragangliomas therefore require an individualized therapeutic regime including surgery, radiation therapy, and observation of tumor growth.

Background Meningitis or cerebrospinal fluid rhinorrhea can occur years or even decades after trauma and can be the first indication of a previously unidentified dural lesion. In spite of being difficult, precise localization of an occult traumatic dural lesion is a necessary prerequisite for duraplasty. Patients and methods In a retrospective study covering a period of 17 years, we identified 27 patients with occult traumatic dural lesions. The dural lesions were localized by high-resolution CT, MRI, fluorescein nasal endoscopy, and CT cisternography. In all cases the expected dural lesion was demonstrated and treated surgically. Results In 23 out of 27 patients (85%), the rhinobasal fistula was detected as a bony defect by CT. Furthermore MRI examination in 100% (5/5), a preoperative fluorescein nasal endoscopy in 50% (10/20) and CT cisternography in 56% (5/9) were able to localize the dural lesion. Conclusion We recommend high-resolution CT and MRI as diagnostic tools of choice in searching for occult dural lesions. Fluorescein nasal endoscopy and CT cisternography are justified as invasive techniques if CT and MRI are inconclusive but clinically CSF leakage is still suggested. The patient will remain at risk of potentially fatal meningitis until the lesion is appropriately repaired by duraplasty. Therefore modern clinical and radiological diagnostic methods should be used to search for an unknown dural lesion.

Numerous diseases can present as orbital or periorbital swelling, i.e. an increase in the volume of the orbital contents or surrounding tissues with or without discoloration of the overlying skin. We have therefore developed a differential diagnostic checklist for clinical evaluation of the patient with orbital or periorbital swelling prior to further investigation. It is based on the history (acuteness of onset, pain, itching, temporal pattern, patient's age, previous illnesses, previous treatment) and the findings on inspection and palpation (location, consistency, redness, pulsation, pseudoproptosis). On account of the long list of differential diagnoses it is rarely possible to make a diagnosis on the basis of a single category alone. However, with an integrative approach which considers the problem from various different angles, it is often possible to arrive at a diagnosis or at least to narrow down the number of possible diagnoses significantly. Imaging procedures and other investigations can then ...

The purpose of obliterating the frontal sinus is to provide a permanent solution to the underlying problem. The material of choice for obliteration is freshly removed abdominal fat. Using magnetic resonance imaging, one can assess the vitality of fat tissue in an obliterated frontal sinus without surgery. Eight patients ranging in age from 22 to 65 years underwent osteoplastic frontal sinus surgery with fat obliteration. The freshly implanted abdominal fat was postoperatively investigated using magnetic resonance tomography. The magnetic resonance examinations were carried out on a supraconductive 0.5 T Magnet (Gyroscan T S II, Philips Medicine Systems, Eindhoven, Netherlands) with a square head spool. We produced T1-weighted spin echo images (TR: 450-550 ms, TE: 20-25 ms), T2-weighted fast spin echo images or in double echo technique in transverse orientation (Tubo SE or TR-2000-2500 ms, TE: 50, 90 ms) and STIR sequences for fat suppression (TJ: 140 ms, TR: 1400 ms, TE: 30 ms). Our goal was to determine the time-dependent distribution of vital fat or fibrous tissue, development of necrosis, cysts, recurrences, inflammatory complications, or re-epithelization of the frontal sinus. Six to 24 months postoperatively, we found vital fat tissue in only three of eight cases. In the other five cases fat necrosis was present. The frontal sinus was filled by granulation tissue or fibrous tissue (once). It is not yet possible to determine when the fat changes to connective tissue. This process varies between individual patients. All eight patients were free of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

In crystalline rare-earth compounds, the magnetoelectric (ME) effect is predominantly decided by single-ion mechanisms. Different procedures will be presented to specify the operator that has to be added to the Hamiltonian. Calculations in mean-field approximation lead to very satisfactory agreement in the temperature dependence of the main elements of the ME tensor with those measured on TbPO4, a substance showing two successive phase transitions. Furtheron, the influence of different types of crystallographic domains on the measurable ME effect is discussed.

The polarized absorption spectra of Ho3+ in HoVO4, HoAsO4, HoPO4 and (Ho0.1, Y0.9)(OH)3 were studied in the range from 11000 to 13500 cm-1 at temperatures between 1.4 and 70 K in magnetic fields up to 4 T. The crystal-field splittings of the term 5I4 were determined for the first time. Previous studies of the term 5I5 were re-examined and completed. The experimental results were critically compared with crystal-field calculations.

The orthorhombic holmium oxisulphate orders as a two-sublattice antiferromagnet atT=3.5 K. In external fields along the crystallographica- andc-directions with large and medium-sized magnetic moment, respectively, a ferrimagnetic phase with 1/3 of the saturation magnetization is passed before the paramagnetic phase is reached. Calculations in mean-field theory reveal that for thec-direction the ferrimagnetic phase is not stable atT=0, it only exists for finite temperatures. Magnetization and susceptibility contain large contributions of van Vleck paramagnetism which at any rate have to be taken into consideration. The phase diagram for the two field directions and the magnetic structures of the different phases are established.

For pt.II see ibid., vol.5, p.945 (1993). Measurements of the linear optical birefringence were used to determine the phase diagram of TbPO4 at temperatures down to 1.4 K. At least one new structural and magnetic phase transition was found that is not detectable in magnetic investigations. Calculations using an appropriate mean-field Hamiltonian, including crystal distortions of monoclinic symmetry, allowed the authors not only to reproduce the experimental phase diagram very satisfactorily but also to give further insight into the magnetic structures and the distortions of the crystal in the various phases.

For pt.I see ibid., vol.5, p.935 (1993). Studies of the Faraday rotation in TbPO4 confirmed the known properties of the different low-temperature phases. Unexpected oscillations, however, were observed in the temperature dependence of the measured rotation in one of the low-symmetry phases. Model calculations of the rotation for a material possessing both Faraday rotation and birefringence did allow an interpretation of the findings, but rather unusual properties of the substance have to be assumed. These calculations additionally showed that the method of measurement influences the results in a typical way so that the optical properties of the substance cannot always be derived directly from the experimental curves.

At low temperatures, TbPO4 shows two phases with antiferromagnetic ordering in immediate succession, the upper one with tetragonal and the lower one with monoclinic crystal symmetry. Magnetisation and magnetic susceptibility were measured in the region of these phases for different external field directions. One main aspect was to study the anisotropy of the susceptibility for a single-domain crystal in one of the low-symmetry phases. Unexpectedly, it turned out that the susceptibility is isotropic in the basal plane.

Bleeding of aneurysm of cervical arteries is an emergency situation in ENT surgery. Compression of trachea and big cervical veins together with blood loss needs immediate treatment. Three cases are demonstrated presenting diagnostic and therapeutic management of one spontaneous respectively posttraumatic aneurysm of the inferior thyroid artery, and two aneurysms of lingual respectively facial artery after tonsillectomy. Interventional angiography plays an important role in overcoming such problems. Intravasal application of a platinum coil stops bleeding of the aneurysm and surgical revision of the neck can be avoided.

The polarized absorption spectra of Ho3+ in HoVO4, HoAsO4, HoPO4 and (Ho0.1,Y0.9) (OH)3 were studied in the range from 5000 to 12000 cm-1. Nearly all crystal-field components were found and their crystal quantum numbers mu , nu and S could be assigned.

The optical absorption spectrum of Ho3+ in LiYF4 and its Zeeman effect in magnetic fields along the crystal c axis were studied in the range from 15400 to 28500 cm-1. The quantum numbers mu of all crystal field components of Ho3+ were determined using linearly and circularly polarized transitions from the ground state. The correlated and spin-correlated crystal fields were used for a fitting procedure of the energy levels.

The magnetic and gravity field produced by a given homogeneous source are related through Poisson's equation. Starting from this consideration, it is shown that some 2D interpretation tools, widely applied in the analysis of aeromagnetic data, can also be used for the interpretation of gravity gradiometric data (vertical gradient). This paper deals specifically with the Werner deconvolution, analytic signal and Euler's equation methods. After a short outline of the mathematical development, synthesized examples have been used to discuss the efficiency and limits of these interpretation methods. These tools could be applied directly to airborne gravity gradiometric data as well as ground gravity surveys after transformation of the Bouguer anomalies into vertical gradient anomalies. An example is given of the application of the Werner deconvolution and Euler's equation methods to a microgravity survey.

Beta-adrenergic receptors were localized and quantified with autoradiographic methods in frozen sections of eyes of albino rabbits using [125I]cyanopindolol and [3H]dihydroalprenolol. Quantification in albino rabbits revealed highest β2-adrenoceptor densities in the ciliary body, the corneal epithelium and the corneal endothelium. Moreover, the iris showed significant amounts of specific binding, whereas the retina and sclera are nearly free of these receptors.

The optical absorption spectrum of Ho3+ in tetragonal (Ho0.1,Y0.9)VO4 was studied in the range from 11000 to 27600 cm-1 at temperatures between 1.4 and 85 K in magnetic fields up to 4 T. Fields along the crystal c axis were used to determine the splitting factors of the doublets. Fields perpendicular to c were applied to induce transitions from the lowest singlet of the ground term, which are forbidden without the field. The energies and the symmetry types of almost all crystal-field components could be established with great certainty.

At low temperatures TbVO4 and DyVO4 exhibit a structural phase transition from the same high-temperature structure to different low-temperature structures. Owing to symmetry different crystallographic domains are possible. Investigations of single crystals of the mixed system (Tbx,Dy1-x)VO4 with a polarising microscope gave information about domain distribution and distortion type. Specific heat measurements, spectroscopic and birefringence data yielded the transition temperatures. The phase diagram of the mixed system may be interpreted as a superposition of the phase diagram of diluted TbVO4 and that of diluted DyVO4. At high concentrations of one of the rare-earth ions the crystals distort like the respective pure substances, whereas at medium concentrations x approximately=0.4 a superposition of the distortion types is observed. The measurements are interpreted in the frame of a mean-field approximation, which is modified by the phenomenological compressible Ising model and by the inclusion of local strains of random distribution.

Die Langerhans-Zellhistiozytose (LCH) ist eine seltene proliferative Erkrankung, die sich vor allem im Kindesalter manifestiert. Das Auftreten lokaler Granulome (Hand-Schuller-Christian-Krankheit, eosinophiles Granulom) oder die breite Ausdehnung auf verschiedene Organsysteme (Letterer-Sive-Krankheit) sind typisch. Spezifische dendritische Zellen (Langerhans-Zellen) des Makrophagen-Monozyten-Systems bilden mit Lymphozyten, Eosinophilen und Histiozyten das klassische Infiltrat bei dieser Erkrankung [2]. Die Atiologie dieser Erkrankung ist noch immer unklar, eine neoplastische oder reaktive Genese wird neben einer aberranten Immunfunktion diskutiert. Aktuelle Studien weisen auf eine klonale Proliferation von Langerhans-ahnlichen Zellen hin [1,3]. Der Erkrankungsgrad reicht von solitaren lytischen Knochenlasionen (meistens bei Erwachsenen) bis hin zu letalen Leukamie-ahnlichen Verlaufen (haufig bei betroffenen Kindern). Kopf- und Halsregion sind typische Lokalisationsorte der benignen Formen [2] und konnen Initialsymptom verschiedener schwerwiegender Variationen sein. Das Felsenbein und der Schadel sind besonders haufig betroffen [5, 6]. Die klinische Symptomatik, das therapeutische Prozedere sowie die Prognose hangen von der Ausdehnung der Erkrankung sowie dem Erkrankungsalter des Patienten ab. Operative Intervention, Radio- und Chemotherapie sind verschiedene therapeutische Optionen. Eine lokalisierte Affektion (z. B. Knochen oder Lymphknoten) haben allgemein eine gute Prognose bei spontaner Remission oder operativer Resektion bzw. Radio Chemotherapie [1]. Die haufigen Manifestationen im Kopf-Hals-Bereich erfordern die Kenntnis dieses Krankheitsbildes in allen an der Schadelbasis tatigen Fachgebieten.

Sinus thrombosis has rarely been associated with closed head injury; more often, thrombosis of the sigmoid or transverse sinus is caused by otogenic inflammations or tumours, or occurs during pregnancy. Symptoms are frequently vague, while untreated thrombus progression may be fatal due to venous congestion and infarction. We report a 32-year-old man presenting with right hearing loss, tinnitus and headache 2 days after a closed head injury. Neurological examination showed no additional abnormality. The EEG showed focal bifrontal slowing. CT revealed a fracture of the occipital bone. MRI and MRA demonstrated complete thrombosis of the right sigmoid and transverse sinuses. After 2 weeks of intravenous heparin therapy followed by warfarin, the patient's hearing improved and MRI and MRA showed complete recanalisation of the sigmoid and transverse sinuses. Venous sinus thrombosis can be an undetected sequel to head injury. Appropriate imaging studies should be carried out to enable therapy to be started as soon as possible.

A new hybrid humidity sensor comprising a conventional capacitance humidity sensor and a planar heating element is described. Owing to its short response time of only a few milliseconds, its great measuring accuracy, large measuring range, and simplicity in handling, the sensor is suitable for measuring water vapour partial pressure in gases with rapidly changing flow and direction, e.g. in ventilated patients in the fields of anaesthesia and intensive care medicine. The small dimensions permit measurements at almost any location within the ventilation system.

The osteoplastic flap procedure with fat obliteration has been hailed as the gold standard of definitive frontal sinus procedures for chronic inflammatory disease. The value of magnetic resonance imaging (MRI) in postoperative follow-up has not yet been sufficiently examined.All postoperative MRI scans performed in patients undergoing surgery between January 1, 1986, and December 31, 1996 were evaluated. The outcome parameters were time-dependent changes in the distribution of fatty or connective tissue and development of necroses or oil cysts, as well as recurrences, inflammatory complications, or mucoceles.Sixty-eight operations were performed in the specified period and a total of 73 postoperative MRI scans from 45 operations were available for evaluation. In 16 cases, between two and five MRI scans were available. The individual time between surgery and the last MRI scan ranged from two weeks to 130 months with an average of 30.1 months. We found four mucoceles 34, 49, 106, and 130 months, respectively. Three of the mucoceles were diagnosed on the first postoperative MRI scan. In the fourth case the mucocele had not been seen on the previous scan. The amount of adipose tissue depictable on the last scan was less than 20% in the majority of cases (58%) and more than 60% in only 18% of cases, although in the latter group the time between surgery and MRI was less than 7 months in half the cases.MRI is the most valuable diagnostic tool after frontal sinus obliteration using adipose tissue. Despite the good soft tissue differentiation, the method has some limitations with regard to detection of small recurrent mucoceles and differentiation between vital adipose tissue and fat necrosis in the form of oil cysts. In these difficult cases, long-term MRI follow-up is necessary for definitive evaluation. We therefore recommend MRI 1, 2, and 5 years after osteoplastic frontal sinus surgery with obliteration.

Hemangiomas of the skull base are rare neoplasms and are easily misdiagnosed as acoustic neuromas when occurring in the internal auditory canal. Among these tumors, ossifying hemangiomas are characterized histologically be newly formed bone tissue within their substance. We describe a 26-year old female patient who presented with left-sided sensorineural hearing loss and tinnitus. T2-weighted magnetic resonance imaging demonstrated a bright space-occupying lesion of the internal auditory canal with extension to the geniculate ganglion. Bony erosions of the internal auditory canal were proved by high-resolution computed tomography. A hemangioma was suspected preoperatively and was resected via a middle cranial fossa approach. Histologically, new bone formations were found in a cavernous hemangioma. In general, radiologic findings can suggest a hemangioma of the internal auditory canal and help to differentiate it from acoustic neuroma. Based on the histological findings of intratumoral bone formation, the hemangioma in our patient was classified as an ossifying hemangioma. However, reactive bone formation at the borders of a tumor in the internal auditory canal can also be mistaken as new intratumoral bone formation.

Surgery is the most common treatment for angiofibromas, but the approach is still a major point of discussion. Five cases of angiofibroma with typical localisation were treated surgically by an endonasal approach at the Fulda Academic Teaching Hospital from 1994 to 1997. This article presents an analysis of the clinical findings, computer tomography and magnetic resonance imaging, preoperative embolization, operative technique and complications. Endoscopic and radiologic follow-up ranging from 5 to 39 months excluded any residual tumour or recurrence. The endonasal microendoscopic approach with adequate preoperative embolization should be considered as an useful technique for removing tumours with considerable size without using an external incision.

Despite increasing advances in endonasal frontal sinus surgery, obliteration of the frontal sinus is necessary in some cases for definitive clearing frontal sinus pathology. Reviewing the literature and considering pathophysiological aspects, successful obliteration of the frontal sinus depends on the complete removal of the mucosa and a sufficient closure of the nasofrontal duct, but not on the material used for obliteration, if special considerations are taken into account and foreign materials are avoided. Complete removal of the mucosa has to include removal of the inner bony cortex of the frontal bone. Occlusion of the nasofrontal duct is achieved with a sufficiently fixed fibrous layer.

The operative treatment and radiation therapy of jugulotympanic paragangliomas (JTP) are still a matter of controversial discussion. In spite of various improvements during the last 50 years, selecting the appropriate treatment modality (surgery, radiation, or observation) is still a challenge.During a 16-year period, 44 patients with 45 JTP (10 at level A/B and 35 at level C/D according to Fisch) were seen at the ENT-department in Fulda. Forty-one cases were treated surgically.Complete resection was possible for level A/B in 100% of the patients (n = 10). Residual tumor was demonstrated for level C in 23% of the patients (5/22) and for level D in 40% (4/10) with a median follow-up time of 69 months. In two cases residual tumor was treated by radiation. Six patients with residual paraganglioma tissue were maintained under observation without any evidence of tumor progression (median follow-up time 39 months). We report one death after the attempt to resect a large residual paraganglioma that had already caused brain stem compression. A sufficient duraplasty could not be achieved following radiation therapy.Complete tumor resection of jugulotympanic paragangliomas of levels A and B is often possible without injury to the cranial nerves. Extensive tumors present difficulties in complete tumor resection and increase the risk of cranial nerve injuries. Advanced paragangliomas therefore require an individualized therapeutic regime including surgery, radiation therapy, and observation of tumor growth.

Meningitis or cerebrospinal fluid rhinorrhea can occur years or even decades after trauma and can be the first indication of a previously unidentified dural lesion. In spite of being difficult, precise localization of an occult traumatic dural lesion is a necessary prerequisite for duraplasty.In a retrospective study covering a period of 17 years, we identified 27 patients with occult traumatic dural lesions. The dural lesions were localized by high-resolution CT, MRI, fluorescein nasal endoscopy, and CT cisternography. In all cases the expected dural lesion was demonstrated and treated surgically.In 23 out of 27 patients (85%), the rhinobasal fistula was detected as a bony defect by CT. Furthermore MRI examination in 100% (5/5), a preoperative fluorescein nasal endoscopy in 50% (10/20) and CT cisternography in 56% (5/9) were able to localize the dural lesion.We recommend high-resolution CT and MRI as diagnostic tools of choice in searching for occult dural lesions. Fluorescein nasal endoscopy and CT cisternography are justified as invasive techniques if CT and MRI are inconclusive but clinically CSF leakage is still suggested. The patient will remain at risk of potentially fatal meningitis until the lesion is appropriately repaired by duraplasty. Therefore modern clinical and radiological diagnostic methods should be used to search for an unknown dural lesion.

It has been shown that inhibition of phosphodiesterase (PDE) or an increase in intracellular cyclic adenosine monophosphate (cAMP) can lower the intraocular pressure in mammalian eyes. The PDE inhibitor rolipram binds with high affinity to a cAMP-dependent PDE. In the following study, receptors for rolipram in the mammalian eye are determined by autoradiography. About 1050 histological sections of rabbit (albino and pigmented), rat, monkey (baboon and marmoset) and human eyes were examined concerning rolipram-binding sites in different structures. The highest specific binding of rolipram to the ciliary body epithelium was seen in human, rabbit and baboon eyes. Marmoset eyes showed the highest specific binding in the ciliary body muscle, rat eyes in the retina. Specific binding was consistently high in the ciliary body epithelium and therefore at the site of aqueous humor formation. Because of these results and the known mode of action of rolipram, one can assume a close connection between rolipram-binding sites and the regulation of intraocular pressure.