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Biomedical subjects

J Berkefeld

Publications and source records attributed to J Berkefeld.

At least 37 records · Page 2Linked to original sources
PubMed2003

Difference in configuration of ruptured and unruptured intracranial aneurysms determined by biplanar digital subtraction angiography.

There is an ongoing discussion about the risk of bleeding from unruptured intracranial aneurysms. Management guidelines were developed recently and some of the recommendations for decision making are based on the anatomical configuration of the aneurysm. The common assumption is that the presence of multiple lobes or a daughter sac indicates a higher risk of rupture. We have investigated the anatomical configuration of ruptured and unruptured intracranial aneurysms using biplanar digital subtraction angiography (DSA). The objective was to determine, whether there was a difference between ruptured and unruptured aneurysms regarding lobulation, the presence of a daughter sac or the shape as measured by the height/neck ratio. Biplanar DSA images of 124 patients were retrospectively analyzed. A total of 53 unruptured and 94 ruptured aneurysms were found (=147 aneurysms in total). Aneurysms of less than 10 mm diameter accounted for 82% of all aneurysms. Overall, 10% of unruptured aneurysm showed a multilobular appearance on DSA compared with 20% of ruptured aneurysms (Fisher's exact test, p=0.10). In the 5-9 mm aneurysm group, multiple lobes were found significantly more frequent in ruptured aneurysms (26% vs. 4%, Fisher's exact test, p<0.05). A height/neck ratio of less than 1.5 was not found in unruptured aneurysms (0/26) but in 21% (12/57) of ruptured aneurysms (p<0.05). Our data provide scientific support for using morphological features for the decision making process in the management of unruptured intracranial aneurysms. An irregular multilobar appearance was significantly more common in aneurysms of 5-9 mm size that ruptured.

Aneurysm, Ruptured↗
PubMed2002

Stent impact on the geometry of the carotid bifurcation and the course of the internal carotid artery.

A measurement system is proposed to evaluate reconstructive effects of carotid stents on the geometry of the carotid bifurcation and the course of the internal carotid artery. To describe deviations of the stenotic internal carotid artery (ICA) from the extended axis of the common carotid artery (CCA) the CCA-ICA angle is measured between the CCA midaxis and the midaxis of the stenotic ICA segment. Maximal extensions of ICA tortuosities perpendicular to the course of the CCA axis are defined as ICA offset. The measurements were applied to DSA images of 224 carotid stenoses to evaluate variation and correlation between the two parameters. Comparative pre- and post-stent evaluation was performed in two series of 55 and 31 carotid stenoses treated with Wallstents and in a historic control group of 35 stenoses treated with Strecker stents. Straight course of the ICA was associated with low angle and low offset values, whereas tortuous course of the ICA showed larger angle and offset. A moderate linear correlation between the two parameters was found. Corresponding to a straightening of the stented segment, Wallstents reduced mean angle and offset values significantly. In five cases of the second series of Wallstents, transferrals of curves above the distal stent end associated with kinks were observed, and offset remained constant or increased. Strecker stent implantation caused no significant changes of bifurcational geometry. The proposed parameters corresponded to visual aspects of ICA tortuosity and detected reconstructive effects of self-expanding Wallstents on the ICA course. The measurement system may provide a basis for geometric evaluation of different stent types or implantation concepts with the aim: to optimize anatomic recanalization results in tortuous high angle-high offset bifurcations.

Aged↗
PubMed2001

Panhypopituitarism associated with severe retroperitoneal fibrosis.

A 43-year-old man, with a history of central diabetes insipidus diagnosed 3 years previously, complained about reduced libido. An MRI scan showed a suprasellar lesion just below the supraoptic recess of the third ventricle. A stereotactically guided biopsy revealed fibrous glia, but no other specific tissue and no inflammatory cells. Two months later the patient presented with fatigue and muscular weakness. Tertiary adrenal failure and hypothyroidism were diagnosed by endocrine function tests and therapy with levothyroxine and hydrocortisone was started. Another 2 months later the patient was admitted with giddiness, nausea, peripheral oedema and oliguria. Radiological imaging and an open transperitoneal kidney exploration showed severe fibrosis around both ureters. Histological examination confirmed the diagnosis of idiopathic retroperitoneal fibrosis. Presumably the suprasellar tumour was the first manifestation of retroperitoneal fibrosis. Once the diagnosis 'idiopathic retroperitoneal fibrosis' is confirmed, fibrotic manifestations and complications involving extra-retroperitoneal tissues including the endocrine system, should be sought.

Adult↗
PubMed2001

Endovascular treatment of symptomatic carotid stenosis using stent placement: long-term follow-up of patients with a balanced surgical risk/benefit ratio.

BACKGROUND AND PURPOSE: Carotid endarterectomy (CEA) is not necessarily beneficial in all patients with symptomatic high-grade (>/=70%) internal carotid artery (ICA) stenosis. Independent risk factors modulate both the individual stroke risk under medical treatment and the combined stroke and death risk after CEA. Endovascular stenting of symptomatic ICA stenosis may be an alternative to CEA in patients with a balanced surgical risk/benefit ratio. METHODS: We included 43 patients (71% men; median age, 67 years) with a recently symptomatic ICA stenosis with >/=70% luminal narrowing in whom the individual sum of medical and surgical risk factors suggested a balanced surgical risk/benefit ratio (risk-modeling appraisal derived from the European Carotid Surgery Trial). After stenting of the stenosed ICA with distal balloon protection, the mean+/-SD follow-up, including clinical and ultrasonographic examinations, was 20+/-11.8 months, with a median number of examinations of 5 per patient. RESULTS: Recanalization of ICA stenoses was technically successful in 40 of 43 procedures (93%). Within the 30-day postinterventional period 1 death occurred (2.5%), and the combined stroke and death rate within follow-up was 5%. Except for 1 asymptomatic ICA occlusion, no restenosis >/=70% occurred during follow-up. CONCLUSIONS: ICA stenting in symptomatic patients with a balanced surgical risk/benefit ratio is technically feasible, with a low periprocedural risk of stroke or death. Furthermore, the risk of future stroke and rate of significant restenosis during long-term follow-up appears to be low, suggesting that ICA stenting may be useful in carotid revascularization and stroke prevention.

Aged↗
PubMed2000

MRI in human immunodeficiency virus-associated cerebral vasculitis.

Cerebral ischaemia caused by inflammatory vasculopathies has been described as complication of human immunodeficiency virus (HIV) infection. Imaging studies have shown ischaemic lesions and changes of the vascular lumen, but did not allow demonstration of abnormalities within the vessel wall itself. Two HIV-infected men presented with symptoms of a transient ischaemic attack. Initial MRI of the first showed no infarct; in the second two small lacunar lesions were detected. In both cases, multiplanar 3-mm slice contrast-enhanced T1-weighted images showed aneurysmal dilatation, with thickening and contrast enhancement of the wall of the internal carotid and middle cerebral (MCA) arteries. These findings were interpreted as indicating cerebral vasculitis. In the first patient the vasculopathy progressed to carotid artery occlusion, and he developed an infarct in the MCA territory, but then remained neurologically stable. In the second patient varicella zoster virus (VZV) infection was the probable cause of vasculitis. The clinical deficits and vasculitic MRI changes regressed with antiviral and immunosuppressive therapy.

AIDS Dementia Complex↗
PubMed2000

[Carotid stenting with embolism prevention].

To optimize the safety of endovascular treatment and to prevent embolic complications, Théron's technique of carotid stenting under balloon protection was applied successfully to 31 patients with high grade extracranial carotid stenoses. Dilatation of the stenosis and stent deployment are performed under temporary balloon occlusion of the distal internal carotid artery. Blood flow is restored after aspiration as well as flushing of potential emboli from the external carotid territory. Initially a hand-mounted non-steerable protection balloon catheter caused technical difficulties in the passage of some stenoses with irregular plaque surfaces. Steerable guide wires with integrated balloons improved the technical feasibility of the protection technique. Up to now no periprocedural strokes were observed. Microscopic examination of the aspirated blood showed numerous cholesterol crystals and fat particles with sizes up to 600 mu which in model experiments with the use of pulsatile perfused silicone carotids showed the effectiveness of aspiration and flushing in the elimination of embolic particles. We assume that the meshwork of the stent, antiplatelets and periprocedural anticoagulation provide no sufficient protection against materials released from the necrotic core of the atherosclerotic plaque. The proven presence of micro-emboli as well as low clinical rates are arguments for further use and development of the protection technique.

Balloon Occlusion↗
PubMed1999

Cryptococcus meningoencephalitis in AIDS: parenchymal and meningeal forms.

CT and MRI in one case of Cryptococcus neoformans infection showed contrast-enhancing parenchymal lesions resembling granulomata or abscesses. After an initial phase without contrast enhancement, the full extent of the lesions was visible within 2 weeks of presentation. The enhancing masses were assumed to represent intracerebral cryptococcomas. Despite evidence of massive meningeal infection on cerebrospinal fluid (CSF) examination, no radiological signs of meningitis, invasion of the Virchow-Robin spaces or ventriculitis could be demonstrated. With antimycotic treatment the contrast enhancement disappeared and cystic, partly calcified lesions remained. Recurrence of meningeal infection without radiological correlates was apparent in this stage. In a second case of proven cryptococcus meningitis, dilation of Virchow-Robin spaces or cysts in the adjacent parenchyma were the main abnormalities on MRI. Enhancing masses were not detected. These cases may represent two different reactions of the immunocompromised hosts to infection with C. neoformans: widening of the perivascular spaces as a correlate of the more typical meningeal infection and enhancing parenchymal lesions as a sign of further invasion from the CSF spaces. Enhancement of cryptococcomas, indicating an inflammatory response in the surrounding brain, is not typical in patients with impairment of immune function.

AIDS-Related Opportunistic Infections↗
PubMed1999

[Indications and contraindications of lacrimal duct balloon dilatation].

PURPOSE: The aim of the study was to determine the indications and contraindications for balloon dacryocystoplasty. MATERIAL AND METHODS: So far 85 patients with severe epiphora because of relative stenosis (n = 47) or occlusion (n = 38) of the nasolacrimal duct have undergone dilation. The success rates were evaluated during the acute phase and the follow-up period of 6-12 months. Treatment failures and recurrence of stenosis were analyzed and compared to the clinical and dacryocystographic indications prior to treatment. RESULTS: A recanalization success rate of 79% was achieved in patients with isolated postsaccal stenoses or short-distance occlusions of the nasolacrimal duct. Patients with additional presaccal and saccal stenoses, filling defects in the duct lumen, or long-distance occlusions had lower initial recanalization rates (66%). Main predictors for recurrent obstructions were active inflammation, filling defects due to calculi, extensive occlusion and post-traumatic lesions. In the absence of these factors 12-month patency rates of 80% were proved. CONCLUSION: Dacryocystoplasty procedures should preferably be performed in patients with circumscribed functional postsaccal stenosis. In these cases a success rate of about 80% is possible. Otherwise the value of the intervention is limited by high failure and recurrence rates.

Adult↗
PubMed1999

Hypervascular spinal tumors: influence of the embolization technique on perioperative hemorrhage.

BACKGROUND AND PURPOSE: Corporectomy is an effective treatment for vertebral metastases; however, massive perioperative hemorrhage is often associated with this procedure. We compared preoperative particle, particle-coil, and coil embolizations of hypervascular spinal tumors prior to vertebral body replacement to determine which prevented perioperative hemorrhage most effectively. METHODS: The vertebral tumors of 59 patients were embolized prior to corporectomy. In 26 cases, only coils were used for the proximal occlusion of feeding segmental arteries. Twenty-four patients received a combination of polyvinyl alcohol (PVA) particles and coils, and nine tumors were embolized with particles alone. We compared intraoperative blood loss between the three groups and 10 other patients who did not undergo embolization prior to corporectomy. RESULTS: Estimation of intraoperative hemorrhage showed a median value of 4350 mL in patients without embolization, 2650 mL in cases of coil embolization, 1850 mL in cases of particle-coil embolization, and 1800 mL in cases of particle embolization. The difference between unembolized patients and those who underwent coil embolization was not statistically significant. Particle and particle-coil embolizations showed very similar results, and reduced hemorrhage significantly as compared to unembolized and proximal coil occlusion cases. Residual bleeding came from the venous system and the neighborhood of the embolized region. CONCLUSION: Particle embolization prior to corporectomy can reduce perioperative hemorrhage. The additional benefit of proximal coil occlusion of arterial feeders is questionable.

Adolescent↗
PubMed1997

Balloon dacryocystoplasty: indications and contraindications.

PURPOSE: To define the indications and contraindications for balloon dacryocystoplasty. MATERIALS AND METHODS: Eighty-five patients with severe epiphora due to partial (n = 47) or complete (n = 38) obstruction of the nasolacrimal duct (NLD) were treated with balloon dacryocystoplasty (DCP). Steerable micro-guide wires with flexible tips were used. Success rates of DCP were evaluated clinically and dacryocystographically during the acute phase and at 6- and 12-month follow-up. Failures and recurrences were correlated with clinical and dacryocystographic indications for treatment. RESULTS: Recanalization was successful in 35 (92%) of 38 patients with isolated focal stenoses (n = 20) or short-distance occlusions (n = 18) of the NLD. Among all 85 patients, recanalization was successful in 25 patients (66%) with complete and 37 patients (79%) with partial obstructions. In the absence of the main predictors for recurrent obstructions (ie, active inflammation, filling defects due to calculi, long-distance occlusions, and posttraumatic lesions), 12-month patency rates were 89% (17 of 19 focal stenoses) and 94% (15 of 16 focal occlusions). Otherwise, reobstruction rate was 46% (12 of 26 cases). CONCLUSION: Balloon dacryocystoplasty is successful only in select cases. To achieve results comparable to those of operative treatment, the indication should be limited to patients with circumscribed focal stenoses or occlusions of the NLD. Active dacryocystitis, dacryocystolithiasis, and posttraumatic lesions are the main contraindications.

Catheterization↗
PubMed1997

[MRI: incidence and evaluation of size and form criteria in hypophysis-healthy probands and in patients with detectable microadenomas].

Magnetic resonance imaging (MRI) was performed in 42 patients with proven microadenomas and in 42 patients with normal pituitary hormone analysis. The normal MRI--anatomy of the pituitary gland and its possible variations with measurement of the volume and comparison of the anatomy with that of the gland after changes caused by microadenomas has to our knowledge not yet described. In this study we measured the height, coronary and sagittal diameter of the pituitary gland in both groups as well as other indirect signs of microadenomas (asymmetry of the gland, sella turcica, and the stalk). The pituitary volume indicates the expansion of microadenomas much better than the gland height (and the other diameters). Normal pituitary glands showed a significant lower volume (525 +/- 137 mm3 [R = 225-800 mm3]) than patients with proven microadenomas (734 +/- 393 mm3 [R = 335-2800 mm3], p < 0.001). The normal pituitary gland and sella turcica show a large variety of anatomic variations. These variations are less frequent in healthy subjects (10-21%) than in patients with microadenomas (48-71%). The described criteria are of some value in diagnosis of a suspected gland hypertrophy or microadenoma. In 75% of the patients with normal pituitary parameters and in 12% of the patients with microadenomas no indirect adenoma criteria was found in our study.

Adenoma↗
PubMed1997

[Radiologic appearance of primary anomalies of the lymphatic vessel system of the lung. Review and personal results].

Congenital disorders of the lymphatics of the lung are rare. On the basis of a literature review and our own experiences the disorders are divided into four groups and their radiographic findings are described. Pulmonary lymphangiectasia shows not typical signs. As an expression of the underlying pathophysiologic processes CT shows thickening of interlobular septs, interstitial edema and pleural effusions. Neither architectural distraction nor thickening of intralobular septs was seen. Lymphangioleiomyomatosis shows rather typical findings with multiple thin-walled bullae. In contrast to the opinion that architectural distraction is not seen in LAM we sometimes found signs of fibrosis. Disseminated pulmonary lymphangioma is characterised by proliferation of lymph vessels. CT-findings of this disorder have not been described before. CT shows multiple disseminated nodules of up to 2.5 cm accompanied by multiple bullae of similar distribution and size.

Humans↗
PubMed1996

Balloon dacryocystoplasty: an alternative treatment for obstructed tear ducts.

Twenty-two patients with severe epiphora due to relative (n = 13) or absolute (n = 9) stenoses of the nasolacrimal duct were treated by means of radiologically guided balloon dacryocystoplasty. The recanalization was performed with a steerable microguide wire with flexible tip, which was advanced through the lacrimal draining system and manipulated out of the nasal cavity. A 3-mm PTA balloon was then introduced from the nasal site. In 20 of 22 cases the procedure was technically successful. Dacryocystography proved a normal lumen in 9 of 20 patients and an improvement without impairment of flow in another 8 cases. Two months after dilation a clear regression of epiphora could be demonstrated in 17 of 20 patients. The procedure was complicated by the occurrence of 2 reobstructions within the first 3 months; other serious side effects were not observed.

Adult↗
PubMed1996

[Universal organ involvement in Rendu-Osler-Weber disease: interdisciplinary diagnosis and interventional therapy].

A case of hereditary hemorrhagic teleangiectasia (HHT, Morbus Rendu-Osler-Weber) in a 63-years-old patient presenting with recurrent gastrointestinal and nasopharyngeal bleeding who required transfusion of 100-200 units of red blood cell concentrate a year is reported. Endoscopically, one source of bleeding could be located in the upper part of the jejunum. Multiple Osler spots were found in the antrum, the bulbal and descending part of the duodenum without signs of bleeding. Colonoscopy revealed no further lesions. Selective mesentericography visualized dilatation of the arterial arcardes in the duodenal region with early venous filling. During coeliacography, parenchymal deposits of contrast medium appeared in the liver. Numerous angiodysplastic arterial alterations from the lower ethmoidal arteria were shown to be another source of bleeding. They were embolized using microspheres and thereby terminating epistaxis. Termination of epistaxis was the crucial prerogative for the consecutive aortal valve replacement. At abdominal ultrasound, the liver harbored multiple anechoic lesions and a bigger cystic formation with portal inflow and early venous distribution. This teleangiectatic portovenous-malformation was confirmed on abdominal computertomography and on T1-enhanced images of MRT, too. This case examplifies the universal character of organ distribution in HHT and underlines the value of complementary diagnostic and therapeutic modalities.

Combined Modality Therapy↗
PubMed1995

[Balloon dilatation of relative postsaccal lacrimal duct stenoses].

In ten patients with incomplete postsaccal stenosis radiology examined by digital subtraction dacryocystorhinography, an overpressure ballooning was done with a small foot vessel balloon with hydrophilic surface under image intensiver control. The balloon was inflated with a diluted suspension for visualization of the balloon and widening of the stenosis. In eight patients recovery was continuous without any treatment, in one with topical application of vasoconstrictor eye drops. In one patient there was a recurrence. Balloon of incomplete postsaccal lacrimal pathway dilatation stenosis is an adequate and minimally invasive therapy.

Angiography, Digital Subtraction↗
PubMed1994

[Intervention and clinical aspects combined with endovascular irradiation of intimal hyperplasia of the vascular system].

After implantation of stents in femoropopliteal arteries we found restenosis or occlusions by intimal hyperplasia in up to 40% especially in the hunter's channel. Repeated balloon angioplasty and prophylactic endovascular radiotherapy with a surface dose of 12 Gy in the vessel wall using an iridium 192 source in the same investigational session is a new technique to reduce or eliminate further recurrence. All 18 patients had developed recurrent stenoses or occlusions 6-8 months after original stent implantations. The patients have not redeveloped recurrent obstructions after this treatment, which up to date showed no short term or long term complications. We conclude that the encouraging results of this pilot study justify further randomized trials.

Aged↗