Using transcranial duplex sonography for monitoring vessel patency during surgery for intracranial aneurysms.

This article reports a method for reliable intraoperative monitoring of blood flow velocities in the basal cerebral arteries during clipping of intracerebral aneurysms. Transcranial color-coded duplex sonography provides practical integration of transcranial Doppler technology with real-time imaging capabilities through the intact human skull. With a computerized sonography system equipped with a 2.5-MHz probe in 50 healthy volunteers, the contralateral internal carotid artery, A1 and A2, as well as M1 and P1 vessels were identified and measured in most patients. In 13 patients undergoing dipping of intracranial aneurysms, the technique successfully imaged 12; it allowed definitive identification of vessels potentially threatened by clipping and not fully visible to the surgeon. Data were easily comparable to preoperative data. This noninvasive, repeatable neuroimaging technique provides useful intraoperative information about intracranial hemodynamics during dipping of intracranial aneurysms.

A new technique of dural closure--experience with a vicryl mesh.

Treatment of postoperative dural CSF leaks following posterior fossa surgery remains a difficult and often perplexing problem. Their management includes either non-operative management or surgical re-exploration. In order to avoid CSF leaks we developed a simple but effective method using a well-cut sheet of a vicryl-poly-p-dioxanone mesh (Ethisorb) covering the whole defect of the craniectomy. This paper presents our technique of dural closure, experiences with and advantages of the vicryl mesh in comparison with conventional procedures using muscle patches in combination with fibrin sealant or fibrin glue alone. Attention is focused upon the frequency of postoperative complications, in particular infection rate and CSF leaks. Furthermore, histomorphological observations after implantation of a vicryl mesh are demonstrated. In conclusion, due to its specific qualities we consider the vicryl mesh as a suitable dural substitute with potential advantages over currently used material.

Intracerebral subependymomas. Clinical and neuropathological analyses with special reference to the possible existence of a less benign variant.

The frequency of asymptomatic subependymomas was 0.4% in 1,000 serial routine necropsies and 0.7% in symptomatic subependymomas from 1,000 serial surgical specimens of intracranial neoplasms. Among patients with subependymoma (7 symptomatic and 4 asymptomatic), we found 3 cases of marked nuclear polymorphism (NP) in biopsy specimens. The subjective NP was objectively quantified by computer-assisted morphometry, by which a significant difference in nuclear size between these three cases and other cases (p less than 0.005) was revealed. This morphological characteristic correlated with the results of DNA-analysis by flow fluorescence cytometry (FFCM): subependymomas with NP demonstrated higher S and G2/M phases in a diploid pattern than other benign gliomas of our series. From the clinical data including prognosis, however, no remarkable difference was found between the NP group and other groups. The possible existence of less benign variant should be considered in the diagnosis and treatment of subependymoma.

Ganglioglioma containing osseous tissue and neurofibrillary tangles.

A ganglioglioma involving the temporoparietal lobe in a 49-year-old patient displayed several unusual histopathologic features. A large central focus of osseous tissue that was found may have resulted from metaplasia of a mesodermal component of the lesion. In addition, occasional ganglioma cells showed neurofibrillary tangles and granulovacuolar changes. The presence of these cytoplasmic structures, usually seen in Alzheimer's disease and other degenerative conditions, within a ganglioglioma emphasizes the diverse settings in which such neuronal changes may occur and may provide clues to their pathogenesis.

Extradural spinal angiolipoma with secretory activity. An ultrastructural, clinico-pathological study.

The light and ultrastructural analyses of an extradural intraspinal angiolipoma causing symptoms of spinal cord compression, are reported. The tumour showed morphological evidence of an endocrine-like secretory activity of fat cells, with an apparent mechanism of secretory function that has not previously been described for angiolipomas. The secretory granules, containing a lipid-like material, were covered with a continuous basement membrane originating from the basement membrane of the adipocyte.

[Detection of rhinoliquorrhea with 99mTc-labelled human serum albumin]. / Zur Problematik des Nachweises einer Rhinoliquorrhoe mit 99mTc-markiertem Humanserumalbumin.

99mTc-labelled human serum albumin was used in 42 patients, 35 without and 7 with proven rhinoliquorrhoea, to combine liquor scintigraphy with the detection of liquor fistula. Since some 99mTc is split off from albumin during the time of investigation and is actively secreted by mucous membranes and salivary glands it was not possible to detect liquorrhoea by calculation of activity ratios like that of secretion of the nose to blood or saliva. But dividing the activity in the secretion of the nose by that in saliva after 2 and 6 hrs this ratio was independent of the amount of activity and had a sensitivity of 100% and a specificity of 93% in detecting a liquor fistula. Combining scintigrams of the subarachnoidal space with the search for liquorrhoea using an always available radiopharmaceutical such as labelled HSA might be attractive. In 4 of 7 patients with a liquor fistula there was additionally a pathologic result obtained with scintigraphy of the subdural space.

Ultrastructural aspects of striated muscle fibers in health and disease.

The application of electron microscopy to skeletal muscle is pertinent to 1. cytological analysis of normal muscle fibers; 2. cytopathology of muscle fibers; 3. systematic ultrastructural analysis of classic muscle diseases; 4. ultrastructure of muscle fiber inclusions; 5. neuromuscular conditions classified by electron microscopy; 6. diagnosis of individual muscle biopsies.

Schwannoma of the sellar region.

A 25-year-old woman who had experienced brief periods of loss of consciousness and grand mal seizures was found to have a midline mass in the sellar region as evidenced by computer tomography and angiography. Preoperatively, it was thought to be a meningioma but histologically and ultrastructurally it turned out to be a Schwannoma. Since cranial nerves were not involved, clinically or morphologically, this nerve sheath tumour could have originated from Schwann cells of sensory, possibly trigeminal, nerves, vasomotor nerves, or ectopic Schwann cells.

[Muscle biopsy (author's transl)]. / Muskelbiopsie.

Modern morphological diagnostic methods for neuromuscular diseases are based on enzyme histological and electron microscopic techniques. By enzyme histochemical differentiation of fiber types, early morphological changes such as Type I atrophy in myotonic dystrophy, or particular disease forms like Type II atrophy or congenital fiber type disproportion and other congenital myopathies associated with a Type I atrophy may be detected. The ultrastructural characteristics and the fine structure of autofluorescent lipopigments rich in phosphatases in the skeletal muscle fiber permit appropriate diagnosis of the individual types of congenital myopathy or neuronal ceroid lipofuscinosis.