Traumatic cervical spinal cord injury: a prospective clinical study of laryngeal penetration and aspiration.

STUDY DESIGN: Prospective cohort study. OBJECTIVES: Dysphagia is a relatively common secondary complication in patients with traumatic cervical spinal cord injuries (TCSCI). The purpose of this study was to determine the incidence of aspiration and penetration in patients with acute TCSCI. SETTING: Tampere University Hospital, Tampere, Finland. METHODS: A total of 46 patients with TCSCI were evaluated with a videofluoroscopic swallowing study (VFSS). Rosenbek's penetration-aspiration scale (PAS) was used to classify the degree of penetration or aspiration. The medical records of each patient were systematically reviewed. RESULTS: Of the 46 patients, 85% were male. The mean age at the time of the injury was 62.1 years. Most patients had an incomplete injury (78%), and most of them due to a fall (78%). In the VFSS 19 (41%) patients penetrated and 15 (33%) aspirated. Only 12 (26%) of the patients had a PAS score of 1 indicating that swallowed material did not enter the airway. Of the patients who aspirated, 73% had silent aspiration. CONCLUSION: The incidence of penetration or aspiration according to VFSS is high in this cohort of patients with TCSCI. Therefore, the swallowing function of patients with acute TCSCI should be routinely evaluated before initiating oral feeding. VFSS is highly recommended, particularly to rule out the possibility of silent aspiration and to achieve information on safe nutrition consistency.

Chronic subdural haematoma after endoscopic treatment of a supracellar arachnoid cyst.

Neuroendoscopy is considered a safe treatment option for intracranial arachnoid cysts. However a variety of complications has been reported after such interventions. Here we present the first case of a chronic subdural hematoma two months after the combined treatment of a supracellar arachnoid cyst with endoscopic third ventriculostomy and cyst fenestration.

Interrelationship of cartilage composition and chondrocyte mechanics after a partial meniscectomy in the rabbit knee joint - Experimental and numerical analysis.

Site-specific and depth-dependent properties of cartilage were implemented within a finite element (FE) model to determine if compositional or structural changes in the tissue could explain site-specific alterations of chondrocyte deformations due to cartilage loading in rabbit knee joints 3 days after a partial meniscectomy (PM). Depth-dependent proteoglycan (PG) content, collagen content and collagen orientation in the cartilage extracellular matrix (ECM), and PG content in the pericellular matrix (PCM) were assessed with microscopic and spectroscopic methods. Patellar, femoral groove and samples from both the lateral and medial compartments of the femoral condyle and tibial plateau were extracted from healthy controls and from the partial meniscectomy group. For both groups and each knee joint site, axisymmetric FE models with measured properties were generated. Experimental cartilage loading was applied in the simulations and chondrocyte volumes were compared to the experimental values. ECM and PCM PG loss occurred within the superficial cartilage layer in the PM group at all locations, except in the lateral tibial plateau. Collagen content and orientation were not significantly altered due to the PM. The FE simulations predicted similar chondrocyte volume changes and group differences as obtained experimentally. Loss of PCM fixed charge density (FCD) decreased cell volume loss, as observed in the medial femur and medial tibia, whereas loss of ECM FCD increased cell volume loss, as seen in the patella, femoral groove and lateral femur. The model outcome, cell volume change, was also sensitive to applied tissue geometry, collagen fibril orientation and loading conditions.

Composition, structure and tensile biomechanical properties of equine articular cartilage during growth and maturation.

Articular cartilage undergoes structural and biochemical changes during maturation, but the knowledge on how these changes relate to articular cartilage function at different stages of maturation is lacking. Equine articular cartilage samples of four different maturation levels (newborn, 5-month-old, 11-month-old and adult) were collected (N = 25). Biomechanical tensile testing, Fourier transform infrared microspectroscopy (FTIR-MS) and polarized light microscopy were used to study the tensile, biochemical and structural properties of articular cartilage, respectively. The tensile modulus was highest and the breaking energy lowest in the newborn group. The collagen and the proteoglycan contents increased with age. The collagen orientation developed with age into an arcade-like orientation. The collagen content, proteoglycan content, and collagen orientation were important predictors of the tensile modulus (p < 0.05 in multivariable regression) and correlated significantly also with the breaking energy (p < 0.05 in multivariable regression). Partial least squares regression analysis of FTIR-MS data provided accurate predictions for the tensile modulus (r = 0.79) and the breaking energy (r = 0.65). To conclude, the composition and structure of equine articular cartilage undergoes changes with depth that alter functional properties during maturation, with the typical properties of mature tissue reached at the age of 5-11 months.

Site-specific cell-tissue interactions in rabbit knee joint articular cartilage.

Relationships between cartilage structure and superficial in situ chondrocyte deformations were investigated from 6 different knee joint locations (n=10 knees). Depth dependent cartilage structure and composition were quantified with microscopic/microspectroscopic methods. Medial tibial cartilages had the lowest superficial collagen content, highest collagen orientation angle, and highest proteoglycan content in the pericellular matrix relative to that in the extracellular matrix, coupled with the largest chondrocyte deformations. In contrast, femoral groove and lateral tibial cartilages had the highest superficial collagen contents, lowest collagen orientation angles, and low normalized proteoglycan contents in the pericellular matrix, coupled with the smallest chondrocyte deformations. To study cell-tissue interactions further, observations (n=57) from all locations were pooled and a multivariable linear regression was performed. Cell width deformations (R2=0.57) correlated with collagen orientation angle (standardized regression coefficient ß=0.398) and collagen content (ß=-0.402). Cell height deformations (R2=0.52) also correlated with collagen orientation (ß=-0.248) and collagen content (ß=0.455). Cell volume change upon cartilage compression (R2=0.41) correlated with collagen content (ß=0.435) and proteoglycan content (ß=0.279). In conclusion, higher collagen and proteoglycan contents combined with lower collagen orientation angle in the extracellular matrix were related to reductions in superficial chondrocyte deformations. Also, a steep gradient of proteoglycan content from the extracellular to the pericellular matrix was associated with increased cell deformation, particularly in the medial tibial plateau cartilage.

Early in situ changes in chondrocyte biomechanical responses due to a partial meniscectomy in the lateral compartment of the mature rabbit knee joint.

We determined the biomechanical responses of chondrocytes to indentation at specific locations within the superficial zone of cartilage (i.e. patellar, femoral groove, femoral condylar and tibial plateau sites) taken from female New Zealand white rabbits three days after a partial meniscectomy in the lateral compartment of a knee joint. Confocal laser scanning microscopy combined with a custom indentation system was utilized to image chondrocyte responses at sites taken from ten contralateral and experimental knee joints. Cell volume, height, width and depth changes, global, local axial and transverse strains and Young׳s moduli were determined. Histological assessment was performed and proteoglycan content from the superficial zone of each site was determined. Relative to contralateral group cells, patellar, femoral groove and lateral femoral condyle cells in the experimental group underwent greater volume decreases (p < 0.05), due to smaller lateral expansions (with greater decreases in cell height only for the lateral femoral condyle cells; p < 0.05) whereas medial femoral and medial tibial plateau cells underwent smaller volume decreases (p < 0.05), due to less deformation in cell height (p < 0.05). Proteoglycan content was reduced in the patellar (p > 0.05), femoral groove, medial femoral condyle and medial tibial plateau experimental sites (p < 0.05). The findings suggest: (i) cell biomechanical responses to cartilage loading in the rabbit knee joint can become altered as early as 3 days after a partial meniscectomy, (ii) are site-specific, and (iii) occur before alterations in tissue mechanics or changes detectable with histology.

Site-dependent biomechanical responses of chondrocytes in the rabbit knee joint.

Biomechanical responses of chondrocytes were determined in specific locations within the superficial zone of patellar, femoral groove, femoral condyle and tibial plateau cartilages obtained from female New Zealand White rabbits. A confocal laser scanning microscope combined with a custom indentation system was utilized for experimentation. Changes in cell volumes and dimensions (i.e. cell height, width and depth) due to loading, global, local axial and transverse strains were determined for each site. Tissue composition and structure was analysed at each indentation site with digital densitometry, polarized light microscopy and Fourier transform infrared imaging spectroscopy. Patellar cells underwent greater volume decreases (compared to femoral groove cells; p<0.05) primarily due to greater decreases in cell height (p<0.05), consistent with greater levels of both global and local axial strains (p<0.05). Lateral condyle cells underwent greater volume decreases (compared to lateral plateau cells; p<0.05) primarily due to greater decreases in cell height, consistent with greater levels of tissue strains (p<0.05). Medial condyle cells underwent smaller volume decreases (compared to medial plateau cells; p<0.05) primarily due to elevated cell expansions in the depth direction, which was consistent with greater levels of minor transverse strains (p<0.05). Site-dependent differences in collagen orientation angles agreed conceptually with the observed cell dimensional changes. Chondrocyte biomechanical responses were highly site-dependent and corresponded primarily with the orientation of the collagen fibrils. The observed differences were thought to be due to the different biomechanical loading conditions at each site.

Evidence for excess long-term mortality after treated subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The purpose of this study was to examine the long-term mortality rate of patients with aneurysmal subarachnoid hemorrhage (SAH) compared with that of the general population. METHODS: Aneurysmal SAH patients who were treated for ruptured aneurysm from 1977 through 1998 in a tertiary referral center (n=1537) were followed up for a median of 7.5 years. Dates and causes of death were determined. Standardized mortality ratios (observed/expected deaths) according to age, sex, and Glasgow Outcome Scale at 12 months after surgery were calculated. RESULTS: The mortality rate among patients with good recovery at 12 months was twice that of the general population. The excess mortality appeared to be most evident in younger age groups. Cerebrovascular and cardiovascular diseases were the principal causes of premature death. The result was similar among patients without preexisting cardiovascular diseases at the time of SAH. CONCLUSIONS: Aneurysmal SAH patients have an excess mortality rate even after successful treatment of ruptured aneurysms. Therefore, aneurysmal SAH should be viewed more as one aspect of a chronic general vascular disease, and more attention should be given to treatment of risk factors and long-term follow-up of these patients.

Familial subarachnoid hemorrhage in east Finland, 1977-1990.

The familial occurrence of cerebral aneurysms in a defined clinical group of 1150 patients from a defined catchment area was studied. Two or more proven aneurysmal subarachnoid hemorrhage (SAH) patients within the same family were included. Of these 1150 patients, 113 (10%) had a proven familial occurrence of aneurysmal SAH. These 113 patients form 91 SAH families with a total of 203 aneurysm patients. Fifty-four percent of the patients were female, and the mean age in female patients was 49 years and in male patients was 44 years. In 23% of the families, three or more members were identified as having cerebral aneurysms. Middle cerebral artery aneurysms were the most common type (47%). Based on the high incidence (10%) of familial intracranial aneurysms among SAH patients, a prospective study of healthy family members for incidental intracranial aneurysms was performed, with positive findings of 12%.

Special features of familial intracranial aneurysms: report of 215 familial aneurysms.

FAMILIAL INTRACRANIAL ANEURYSMS (FIAs) were compared with nonfamilial aneurysms (non-FIAs); the study group from east Finland included 167 family members from 85 families with FIAs. In every family, there has been two or more proven cases of subarachnoid hemorrhages among first-degree family members. Two-hundred and fifteen FIAs were found. The patients with FIAs were younger, and their aneurysms were smaller. Half of the FIAs were on the middle cerebral artery (n = 106 of 215), preferentially on the right side. Nearly one-third of the ruptured FIAs were smaller than 6 mm, and more than 80% of the aneurysms were under 14 mm in diameter. There were no significant differences between the frequency of aneurysms at mirror sites in FIA and non-FIA groups. Among siblings with FIAs, the frequency of pairs with age at onset within 10 years of each other was more than twice that expected from randomly selected pairs in the non-FIA group.

Magnetic resonance angiographic screening for asymptomatic intracranial aneurysms: the problem of false negatives: technical case report.

To emphasize the limitations of magnetic resonance angiographic screening for intracranial aneurysms, we present the case of a patient with a false-negative screening result, unfortunately advancing to rupture of the aneurysm. An asymptomatic woman underwent magnetic resonance angiographic screening in an investigational setting. Three years later, she had an onset of sudden headache, after which her condition rapidly deteriorated. Severe subarachnoid hemorrhage and an intracerebral hematoma were diagnosed. Conventional angiography detected a small ruptured middle cerebral artery trifurcation aneurysm and two very small aneurysms. There are still limitations in the ability of magnetic resonance angiography to detect small or very small aneurysms. Even small-probability findings should always be confirmed or excluded by conventional angiography.

A ten percent prevalence of asymptomatic familial intracranial aneurysms: preliminary report on 110 magnetic resonance angiography studies in members of 21 Finnish familial intracranial aneurysm families.

The population in eastern Finland has been stable for generations, causing a high degree of genetic isolation and providing excellent possibilities for follow-up studies. Of 91 families with familial intracranial aneurysms, 21 were randomly selected for prospective magnetic resonance angiography studies for intracranial aneurysms. Sixteen intracranial aneurysms were detected in 11 asymptomatic family members of a total of 110 studied. The prevalence of intracranial aneurysms among these familial intracranial aneurysm families is 10%, approximately 10 times higher than in the average population. Our findings suggest that family members of familial intracranial aneurysm families should be examined for intracranial aneurysms. Familial intracranial aneurysm may be a genetic disorder.

The effect of subchronic administration of vigabatrin on learning and memory in nonepileptic rats.

The present experiments investigated whether subchronic administration of vigabatrin, a GABA-mimetic drug, affects the performance of normal rats in the behavioural tasks assessing learning and memory. The effects of vigabatrin [50-200 mg/kg (IP)/day] administration on the acquisition and retention of water maze and passive avoidance task were studied. According to the results of three experiments, vigabatrin treatment did not markedly impair the acquisition or retention of water maze task. Furthermore, vigabatrin-treated rats were not inferior to saline-treated rats in reversal learning of water maze task. On the other hand, vigabatrin treatment slightly increased the speed of swimming in rats. The administration of vigabatrin did not affect the performance (training latency, number of training trials, testing latency) of rats in the passive avoidance task. According to these results, the effects of vigabatrin, a new antiepileptic drug, on the performance of nonepileptic rats were modest in behavioural tasks used to assess learning and memory.

Castleman's disease of the leptomeninges--immunohistochemical findings in 2 cases.

OBJECTIVE: Castleman's disease is an uncommon benign lymphoproliferative disorder that arises in lymph nodes. Few cases of Castleman's disease affecting the central nervous system have been described. CASE HISTORY: We report 2 new cases of Castleman's disease confined solely to the leptomeninges. The patients were referred to neurosurgery with presumptive clinical diagnosis of meningiomas. Histological investigation of the operative specimens taken from the abnormal leptomeninges revealed nodular lymphoid areas with multiple germinal centers surrounded by concentrically layered proliferations of small lymphocytes. Histologically, these 2 cases fulfilled the classification criteria for the mixed and for the hyaline-vascular type of Castleman's disease. The immunohistochemical analysis revealed a polyclonal B cell proliferation in the lesions with perifollicular T cell proliferation with the T helper cell predominance. CONCLUSIONS: The authors conclude that Castleman's disease involving the leptomeninges have a similar immunological pattern reported for the disease in extracranial locations and that, though being rare, Castleman's disease should be considered as a differential diagnosis when dealing with mass lesions of leptomeninges.

Fatal inhalation injury caused by airway fire during tracheostomy.

A 45-year-old man needed emergency tracheostomy and cranioplasty. He was intubated with a cuffed oral polyvinylchloride endotracheal tube and ventilated with 100% oxygen before tracheal incision. During opening of the trachea using diathermy, a popping sound was heard and flames originating from the tracheal incision were observed. The endotracheal tube was charred and its lumen had melted. Immediately after the incident, bronchofibroscopic examination revealed inhalation injury. After remaining for 8 weeks in hospital, the patient was transferred to a health care centre, where he was found dead in his bed.

Subarachnoid haemorrhage of unknown aetiology.

Eighty-six of 996 patients with primary subarachnoid haemorrhage (SAH) had negative pan-angiography studies. These 86 patients with subarachnoid haemorrhage of unknown origin (SAH-NUD) were compared with 853 patients sustaining an aneurysmal bleed (SAH-A) admitted during the same period 1980-1989. The age and sex distribution of both groups were similar. The SAH-NUD group was in better condition on admission, with less blood evident on CT scan. All 16 (repeat control) angiography studies in the SAH-NUD group were negative. During a follow-up period ranging from 1 to 10 years (mean 5.4 years), two patients experienced rebleeding with negative repeat angiographies and subsequent total recovery. Using the Glasgow Outcome Scale (GOS) the final outcome was good in 86% of the study group and 54% of the aneurysm group. However, half of the SAH-NUD patients complained of persistent symptoms at long-term follow-up. Thus, despite a generally good prognosis, for a given individual SAH-NUD may be catastrophic with many residual symptoms persisting for the rest of the person's life.

Familial subarachnoid hemorrhage. Outcome study.

BACKGROUND AND PURPOSE: The aim of our study was to compare outcome and its determinants in familial subarachnoid hemorrhage and in sporadic subarachnoid hemorrhage in a large and well-documented patient population. METHODS: Patients with aneurysmal subarachnoid hemorrhage (SAH) treated at the Department of Neurosurgery, Kuopio University Hospital, from 1977 to 1995 were included. Patients with polycystic kidney disease were excluded. The Glasgow Outcome Scale (GOS) score at 12 months was studied. RESULTS: There were 120 patients (97 first-, 15 second-, and 8 third-degree family connections) in 96 different families with familial SAH and 1237 patients with sporadic SAH. Age, gender, and admission grade on the Hunt and Hess scale did not differ between these 2 groups. In both groups >80% of patients were in relatively good condition at admission. The outcome was good (GOS score of 1 to 2) in 87 patients (73%) with familial SAH and in 874 patients (71%) with sporadic SAH. Analysis of 20 variables, including presence of coexisting diseases, aneurysm site and size, amount of blood shown on CT scan, intraventricular bleeding, preoperative intracerebral hematoma and hydrocephalus, as well as postoperative bleeding and vasospasm, revealed no significant differences between study groups. The degree of family connection (first-, second-, and third-degree) did not have any statistically important effect on outcome in the familial group in the Finnish study population. In multivariate analysis the knowledge of familial SAH was not an independent prognostic factor. CONCLUSIONS: Admission status, postoperative course, and outcome were similar in the familial and sporadic SAH groups in this Finnish population, in contrast to previous results. Familial SAH may not be a significant risk factor for poor outcome.