Epicardial cryosurgery as used in ablation of accessory atrioventricular pathways: effect on valvular function in the dog

Epicardial cryosurgery for ablation of atrioventricular accessory pathways has surgical advantages. However, it is applied directly to the valve base. To assess the risk of valve impairment, 10 anaesthetized dogs were subjected to standardized epicardial cryosurgery of the right atrioventricular junction. Two of these underwent sham procedure (dissection only). Valve function was assessed by colour Doppler echocardiography preoperatively and at 2 days, 1 week, 2 weeks and 10 weeks postoperatively. Three out of the eight animals subjected to cryosurgery developed moderate (grade 2/4) tricuspid insufficiency, which appeared at 1 week postoperatively, following regression of congestive oedema. Two out of the three cases of TI were associated with leaflet prolapse. No tricuspid insufficiency was seen in the sham-operated animals. At the end of each interval two animals were killed for histological examination. Histological examinations showed that cryolesions extended a maximum of 3 mm into the valve leaflet. The tricuspid insufficiency is attributed to the extensive scarring (including chondroid metaplasia), which causes retraction and restricted motion of the annulus. It is concluded that cryolesions may impair atrioventricular valve function. Patients undergoing cryosurgery should be monitored postoperatively by echocardiography for atrioventricular valve insufficiency.     

Resection of parietal lobe gliomas： incidence and evolution of neurological deficits in 28 consecutive patients correlated to the location and morphological characteristics of the tumor

OBJECT： The goal of this study is to report the incidence and clinical evolution of neurological deficits in patients who underwent resection of gliomas confined to the parietal lobe. METHODS： Patient demographics, findings of serial neurological examinations, tumor location and neuroimaging characteristics, extent of resection, and surgical outcomes were tabulated by reviewing inpatient and office records, as well as all pre- and postoperative magnetic resonance （MR） images obtained in 28 consecutive patients who underwent resection of a glial neoplasm found on imaging studies to be confined to the parietal lobe. Neurological deficits were correlated with hemispheric dominance, location of the lesion within the superior or inferior parietal lobules, subcortical extension, and involvement of the postcentral gyms. The tumors were located in the dominant hemisphere in 18 patients （64%）; had a mean diameter of 39 mm （range 14-69 mm）; were isolated to the superior parietal lobule in six patients （21%） and to the inferior parietal lobule in eight patients （29%）; and involved both lobules in 14 patients （50%）. Gross-total resection, documented by MR imaging, was achieved in 24 patients （86%）. Postoperatively, nine patients （32%） experienced new neurological deficits, whereas seven （25%） had an improvement in their preoperative deficit. A correlation was noted between larger tumors and the presence of neurological deficits both before and after resection. Postoperatively higher-level （association） parietal deficits were noted only in patients with tumors involving both the superior and inferior parietal lobules in the dominant hemisphere. At the 3-month follow-up examination, five of nine new postoperative deficits had resolved. CONCLUSIONS： Neurological deterioration and improvement occur after resection of parietal lobe gliomas. Parietal lobe association deficits, specifically the components of Gerstmann syndrome, are mostly associated with large tumors that involve both the superior and inferior parietal lobules of the dominant hemisphere. New hemineglect or sensory extinction was not noted in any patient following resection of lesions located in the nondominant hemisphere. Nevertheless, primary parietal lobe deficits （for example, a visual field loss or cortical sensory syndrome） occurred in patients regardless of hemispheric dominance.     

Dural infolding during C1-2 myelography

Inward buckling of the dura at C1-2 may occasionally occur with hyperextension of the neck and can result in a difficult or unsuccessful puncture when the posterior lateral C1-2 approach is used for cervical myelography. In this circumstance, placement of the head in a neutral or slightly flexed position may widen the posterior subarachnoid space and facilitate the needle puncture.     

Carcinoma arising from reduced enamel epithelium

Intra-osseous squamous cell carcinomas are considered to be derived from odontogenic epithelium. Except for an associated benign odontogenic tumor or a cyst, evidence for an odontogenic origin is only circumstantial. In a 73-year-old male, an intra-osseous squamous cell carcinoma in the mandible could be shown to have originated from reduced enamel epithelium. There were no histological features substantiating the odontogenic origin, other than the continuity of tumor epithelium with reduced enamel epithelium surrounding the crown of an impacted molar tooth. Thus, it is concluded that the odontogenic derivation of an intra-osseous squamous cell carcinoma in the jaw cannot be inferred from specific histological features, but should be based on the exclusion of an oral cavity lining epithelial origin. Still more proof is the demonstration of continuity of the carcinoma with odontogenic epithelium, be it normal, cyst lining or benign odontogenic tumor.     

The prediction of mandibular invasion by squamous cell carcinomas with the expression of osteoclast-related cytokines in biopsy specimens

Destruction of bone by tumour is caused by osteoclasts rather than by tumour cells directly. Tumour cells of invasive oral squamous cell carcinomas (SCC) release osteoclast-related cytokines and cytokines activate osteoclasts. The purpose of this study was to investigate the possibility of predicting mandibular invasion by SCC by analysis of the expression of osteoclast-related cytokines in biopsy specimens of SCC, adjacent or fixed to the mandible. Thirty-five biopsy specimens from the pathology archives were examined from patients who had been treated for SCC, adjacent or fixed to the mandible. The patients were divided into those with and without medullary invasion. The expression of tumour necrosis factor (TNF)–α, interleukin (IL)-6 and IL-11 was studied by immunohistochemical analysis. No significant differences were found in expression of TNF–α, IL-6 and IL-11 between biopsy specimens with or without medullary invasion. Quantification of the density of tumour-infiltrating lymphocytes was not reproducible. In conclusion, the expression of TNF–α, IL-6 and IL-11 in biopsy specimens of SCC, adjacent or fixed to the mandible, is not an appropriate method for predicting the presence of medullary invasion of the mandible.     

The occurrence of osteoarthritis at a minimum of ten years after reconstruction of the anterior cruciate ligament

Objective  

The objective of this study was to evaluate the incidence of radiographic osteoarthritis in the operated knee in comparison with the contralateral knee ten years after a bone-tendon bone patellar autograft ACL-reconstruction and to evaluate to which level patients regain activity ten years after reconstruction.     

Chondromalacia patellae: assessment with MR imaging

Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.     

Suprapancreatic biliary obstruction: CT evaluation

In a 5-year period, 92 patients with biliary obstruction proximal to the pancreatic segment were evaluated with computed tomography (CT). Seventy-three were judged to have technically optimal studies. Observations of the level of obstruction were compared with data from 50 percutaneous transhepatic cholangiograms; CT data enabled the level of obstruction to be correctly predicted in 46. CT enabled correct prediction of the distribution of obstructing lesions in all 18 patients with intrahepatic obstruction. Forty-four of the 73 patients had pathologic examination of the porta hepatitis. CT findings of obstructing mass and lesser omental nodes resulted in correct prediction of malignancy in 25 (92%) of 27 patients; the absence of such findings enabled correct prediction of benign disease in 13 (77%) of 17 individuals. CT is most valuable as a noninvasive means of planning surgical or radiologic drainage procedures in patients with biliary obstruction.     

Condylar hyperplasia. A clinico-pathological analysis of 22 cases

A series of 22 cases of unilateral condylar hyperplasia is presented with the emphasis on histopathological aspects. It is concluded that there are two types of condylar hyperplasia. The first manifests itself in the adolescent or the young adult and represents an exaggerated, normally proceeding growth and maturation process. The histological structure of the condyle in these cases is age-dependent as is shown by a conversion of hyaline growth cartilage into fibrocartilage occurring at about 20 years of age. The second type of condylar hyperplasia, seen in older people, probably represents reactive growth as a response to an eliciting agent that mostly can be identified. In these cases the histological architecture of the condyle is distorted by large masses of hyaline cartilage while there are concomitant degenerative changes in the form of arthrosis. In contrast to the patients suffering from the first type of condylar hyperplasia, the latter ones complain of additional joint symptoms, mostly pain. Moreover it is concluded that joint scintigraphy does not clearly discriminate between genuine condylar hyperplasia and reactive processes due to arthrosis, which may have clinical implications.     

Confirmation of hepatitis C infection: a comparison of five immunoblot assays

BACKGROUND: Recently, new immunoblot assays for the detection of antibodies to hepatitis C virus (HCV) became available. STUDY DESIGN AND METHODS: The performance of five confirmatory anti-HCV immunoblot assays was studied with samples with known HCV antibody and HCV RNA status. The assays were a third-generation strip recombinant immunoblot assay (RIBA-3, Chiron Corp., Emeryville, CA), a second-generation HCV blot (DB-2 blot, Diagnostic Biotechnology, Singapore), the Wellcozyme HCV Western blot (Murex blot, Murex Diagnostics, Dartford, UK), an immunodot HCV assay (Matrix, Abbott Laboratories, Chicago, IL), and the third-generation HCV line immunoassay (Liatek-III, Organon Teknika, Boxtel, The Netherlands). RESULTS: Sensitivity on samples from 48 HCV RNA-positive, second-generation RIBA (RIBA-2)-positive persons and specificity on samples from 31 low-risk donors was 96 percent or better for all assays. The sensitivity on 31 HCV RNA-positive, RIBA-2- indeterminate samples was as follows: Liatek-III, 94 percent; RIBA-3, 90 percent; Murex blot, 61 percent; Matrix, 55 percent; and DB-2 blot, 39 percent. In testing 39 HCV RNA-negative, RIBA-2-indeterminate donor samples, the percentage found to be negative was Liatek-III, 77 percent; RIBA-3, 67 percent; Murex blot, 49 percent; DB-2 blot, 33 percent; and Matrix, 15 percent. The order of sensitivity on four HCV seroconversion series was (from high to low): RIBA-3, Liatek-III, DB-2 blot, Murex blot, and Matrix; the differences were small. CONCLUSION: Detection of HCV antibodies was not refined by the addition of new HCV antigens (NS5, E2/NS1), but by improved classical antigens (core, NS3, NS4). Replacement of the commonly used RIBA-2 will resolve the status of a high proportion of RIBA-2-indeterminate samples.