Experience with peripheral nerve injury in lower extremities

This study reports the results of 43 operations performed on nerves of lower extremities of 43 patients during a period of 7 years from 1999 - 2005 in Mansoura University Hospital and Mansoura Emergency Hospital. There were 15 patients with isolated sciatic nerve injury, 24 with isolated peroneal nerve injury and 4 with isolated tibial nerve injury. All patients were treated with nerve exploration within 1 hour to 7 months after injury and were followed-up for 6 months to 4 years. There were 22 nerve lesions not in continuity [9 needed suture repair and 13 needed sural nerve graft repair], while 21 nerve lesions were in continuity [16 partial lesions needed neurolysis and 5 complete lesions needed neuroma excision and suture repair]. Analysis of the outcome of surgical treatment was performed with respect to the following parameters: period between the injury and operation, patient age, type of injured nerve, mechanism of injury and type of surgical intervention. Overall significant outcome [>/= 3 Louisiana State University Health Science grade] was obtained in 53.5% [sciatic nerve 46%, peroneal nerve 54% and tibial nerve 75%]. According to the type of intervention and lesion categories; lesions not in continuity had a significant outcome 41% [suture repair 55.5% while graft repair 31%], and lesions in continuity had a significant outcome 67% [lesions underwent neurolysis 75%, while lesions underwent suture repair 40%]. Useful function was achieved in 3 [43%] of 7 patients with grafts less than 6 cm in length and in only 1 [16%] of 6 patients with grafts greater than 6 cm in length. The mean time to recovery in patients who underwent surgery was 18 months [range: 1- 32/ ]. In conclusion, the most favourable outcome was obtained with lesions that result in partial lesion in continuity. Considering the rate of spontaneous recovery of post-injection nerve injuries of the sciatic nerve and early onset of skeletal deformities, a closed nerve injury of the lower limb with no recovery within 3 months should always undergo surgery, even if complete functional outcome is not always guaranteed

Spontaneous spinal epidural haematoma

Spinal epidural haematomas [SHE] is a potentially reversible cause of spinal cord and nerve root compression, may be acute or chronic; usually its occurrence may be associated with coagulation dysfunction from medications and disease states. Patients usually present with sudden onset of neurological dysfunction. The prompt diagnosis and treatment of this relatively rare condition, when attained rapidly requires surgical decompression and can result in satisfactory neurological recovery. In the period from 2001 - 2007, 7 patients were diagnosed as spontaneous SEH and managed by urgent spinal cord decompression, age from 12-44 years. Urgent magnetic resonance imaging [MRI] was done for all patients followed by urgent decompression according to the affected levels. Spontaneous spinal epidural haematomas are a rare spinal problem and need immediate diagnosis. Imaging study, mainly MRI according to the sensory level is the key for diagnosis and immediate surgical intervention is the cornerstone to get a good result

Role of apparent diffusion coefficient (ADC) and multivoxel chemical shift proton spectroscopy in grading of brain tumors

Background and Purpose: Grading of brain tumors carries great importance in its evaluation and management. The aim of this work was to evaluate the role of apparent diffusion coefficient [ADC] and multivoxel chemical shift proton spectroscopy in grading of various brain lesions

Subjects and Methods: This study was conducted on 35 patients with brain tumors [11 high grade and 7 low-grade glioma, 7 metastases, 6 meningiomas, and 4 tuberculomas]. They presented with various combinations of neurologic manifestations [headache [24 patients], convulsions [11], focal neurologic deficits [27] and altered sensorium [6]]. They were prospectively evaluated with contrast material-enhanced MR imaging, multi-voxel proton MR spectroscopy [TE = 270 ms], and diffusion-weighted imaging [b = 0, 500, and 1000 s/mm2] before surgery

Results: MR spectroscopy could differentiate benign from malignant tumors but was not useful in grading malignant tumors. In the differentiation of malignant from benign tumors, N-acetylaspartate [NAA]/choline [Cho] and Cho/ creatine [Cr], ratios [P < 0.001] were statistically more significant than NAA/Cr. Lipid and lactate peacks were detected in 8 cases of high grade glioma and 6 cases of matastases but was not detected in any case of low grade glioma. ADCs were effective for grading malignant tumors [P < 0.001] but not for distinguishing different tumor types with the same grade. High-grade malignant tumors [0.85+8 x 10-3 mm2/s] had significantly lower ADC values than did low-grade malignant [1.15 + 9 x 10-3 mm2/s] and benign [1.08 + 12 x 10-3 mm2/s] tumors. Peritumoral ADCs were insignificant in differentiation between high and lowgrade glioma as well as between edema and non enhanced peritumoral infiltration

Conclusion: Combination of calculated ADC values from tumoral core and specific relative metabolite ratios acquired by MR spectroscopy added more information to MR imaging in the differentiation and grading of brain tumors

Impact of uraemia on the shear bond strength between composite resin and tooth structure: sem evaluation

Objectives: This study was aimed to investigate the influence of uraemia on enamel and dentin bond strength to resin composite using a total-etch adhesive system. The micromorphological appearance of resin-tooth interfaces was also investigated

Methods: The adhesive system and the composite resin used in this study were Excite and Tetric EvoCeram [lvoclar/ Vivadent] according to manufacturers' recommendations. Thirty six human molars were used for this study, 28 molar for shear bond test and 8 molars for micromorphological study. The teeth were divided into two groups, A and B, and then each group was subdivided into two subgroups. Teeth of group A were extracted from normal individuals while group B were extracted from uraemic patients. Enamel bonding sites were prepared in the buccal surfaces of subgroups A[1] and B[1] while dentin bonding sites were prepared in occlusal surfaces of subgroups A[2] and B[2] using 600 grits SiC abrasive paper. For shear bond test specimens were etched with 37% phosphoric acid gel and composite rods were bonded with the adhesive resin. Shear bond strengths were determined using a Universal Testing Machine at a cross-head speed of 2mm/min until failure occurred. Fracture modes were examined at 16x magnifications with stereomicroscope. The other 8 specimens were prepared with the adhesive resin only and examined with SEM

Results: Bond strengths to normal enamel were significantly higher compared to normal dentin, uraemic enamel and uraemic dentin. SEM observations revealed shallower etch pattern for uraemic enamel and poor infiltration of resin into dentinal tubules for uraemic dentin compared to normal specimens

Significane: Uraemia had impact on the bond strength of composite resin to tooth structure

Efficacy of platelet-rich plasma mixed with bioactive glass for maxillary sinus augmentation in a dog model [histological and histochemical study]

Twelve mongrel adult male dogs with a complete set of permanent dentition were used in this study. They were randomly divided into four groups [I, II, III and IV] based on time of sacrifice at one month, 1.5 months, 3 months and 6 months postsurgically. Under general anaesthesia; maxillary sinus lift operation was done for all animals on both sides, the left side served as a control side where the osseous defect was filled with bioactive glass particles [BG] and the right side was filled with bioactive glass particles mixed with platelet rich plasma [BG mixed with PRP] and served as study one. The bony specimens at the operation sites were taken after sacrifice; fixed, decalcified and processed for paraffin embedded sections. The sections were studied histologically and histochemically. Histologically with Hx. and E. stain the sections revealed faster bone healing in the study side at all age groups as compared with their counterparts of the control side. Also, with trichrome stain; the bone maturation was also more faster. Histochemically; the PAS reaction was mild at 6 months groups of the study side ahead of the control one. Based on the findings, we can conclude that healing of osseous defect after sinus lift procedure is more enhanced, through an accelerated bone formation and maturation, with the use of BG mixed with PRP than with the use of BG alone

Equine bone graft versus bovine bone on healing of jaw defects in guinea pigs

Purpose: This study was undertaken to demonstrate histologically and histochemically the difference of bone healing using Equine Heterologous Bone versus Bovine Bone in induced bony cavities in the submental area of guinea pigs

Materials and Methods: Fifteen adult male guinea pigs with an average weight of 400-500 grams were used in this study. Each animal was subjected to implantation of the spongy granular form of Equine Heterologous Bone Tissue [Bio Gen] in an induced bony cavity through the right submental area of the mandible adjacent to the midline [study side]. A similar bony cavity was made on the left side [control side] adjacent to the midline in the same animals for implantation of Bovine Bone [Bio-Oss]. Animals were classified into 5 groups [3 animals each] according to the predetermined time of sacrifice; at 1 month [group I], 1.5 months [group II], 2 months [group III], 4 months [group IV] and 6 months [group V]. Bony specimens were decalcified in EDTA and processed for paraffin embedded sections [buccolingual sections of 4 micro thick] for histological and histochemical examination

Results: Both histological and histochemical results showed faster bone formation and maturity of study side osseous defects at all study periods than its counterparts of the control ones. In addition, the total proteins of the formed bone in the study side sections were less than the control side ones

Conclusion: The histological and histochemical results of this study revealed that Equine Bone Tissue was integrated and subsequently replaced by new bone formation with faster maturity than was the Bovine Bone

Immunohistochemical detection of fibronectin in bone wound healing of ovariectomized guinea pigs receiving raloxifene

As Fibronectin [FN] performs essential roles in bone Wound healing and as osteoporosis is considered a complication of ovariectomy, this study was conducted selecting the FN as an immunohistochemical marker in bone wound healing in ovariectomized Guinea Pigs [GP] versus another ovariectomized GP receiving raloxifene as estrogen replacement therapy. Twenty four adult females Guinea Pigs were used, they were divided into two equal groups, control and experimental. Both groups were subjected to ovariectomy. The animals in each group were subjected to the 2[nd] operation to prepare bilateral standardized bony cavity adjacent to the midline in the submental area of the mandible, of each. After the second operation: each animal in the experimental group was received 2mg daily dose EVISTA, [Raloxifene hydrochloride]. Four animals from each group were sacrificed at 15, 30 and 45 days from the second operation, bone specimens were taken for processing and immunohistochemical staining with antimouse cellular FN monoclonal antibody. The results of this study had revealed FN detection in the experimental group bone sections at 15, 30 and 45 days in the bony trabeculae of the healed cavity and in the marrow spaces but in the control group; it was absent in the bony trabeculae at the same intervals. Thus we can conclude that; raloxifene is a new potent medication as estrogen replacement therapy in bone wound healing after ovariectomy

effect of sodium glycodeoxycholate topical application at different concentrations as a drug absorptive enhancer on rabbit buccal mucosa [transmission electron microscopic study]

To avoid the hepatic first pass drugs effects, different absorption enhancers were used to achieve the optimal drug delivery via the buccal mucosa. Twenty male rabbits were used in this study weighing from 400-500 gm. These animals were divided into four groups; the 1[st] one [comprised 2 animals] was considered as a control group, while the 2[nd], 3[rd] and the 4[th] [6 animals each] were considered as experimental groups. A patch material was adhered to the buccal mucosa opposite to the upper first molar of the control group. Also the patch materials soaked with sodium glycodeoxycholate [GDC] solution 1%, 2% and 3% were adhered to the buccal mucosa in the same site of the 2[nd] 3[rd] and 4[th] experimental groups respectively, one hour daily for three weeks. The specimens were taken from the buccal mucosa after sacrification of the animals to be prepared for ultra- structural examination by transmission electron microscope. The results had revealed that the application of 1% of GDC was the safest concentration than 2% and 3% which was the most toxic one as revealed by the presence of deleterious and dramatic harmful ultrastructural changes in desmosmal, hemidesmosomal attachments and in the mitochondriae. These harmful changes had comprised the loss of desmosmal, hemidesmosomal attachments and lysis of mitochondrial matrix and its cristae with the presence of electron dense drug material inside the mitochondriae and in the connective tissue around blood capillaries associated with collagen fibers degeneration. In contradictory, the 1% GDC concentration had passed intercellulary without these pervious harmful intracellular changes indicating that the pathway of GDC 1% concentration is passing through the buccal mucosa intercellulary without intracellular leakage of its drug material. Thus we can concluded that the absorption enhancement is no longer the main problem but instead of that; the safety of the enhancers, the route of administration and the concentration effect relationship of the enhancer are important issues to achieve optimal drug absorption enhancement. So GDC at 1% concentration may improve delivery of various chronic administration of drugs into systemic circulation through buccal mucosa

Scanning electron microscopic study evaluating the effect of 16% carbamide peroxide bleaching gel application at different periods on enamel and dentine

Technology has introduced bleaching gels and pastes that contain carbamide peroxide as a whitening agents. The carbamide peroxide agent has been popular since its use in 1989. The crowns of fifty extracted human anterior teeth were sectioned incisally exposing the dentine and the enamel ring. The teeth were divided into four groups; one control group and three experimental groups. The control one [5 specimens] was subjected to the application of placebo gel. The experimental groups [15 specimens each] were subjected to the application of the bleaching gel. The composition of it was carbamide peroxide 16%, glycerin, buffered polycarboxylic acid and pepermint oil. The 1[st], 2[nd] and 3[rd] experimental groups were exposed to 16% carbamide peroxide bleaching gel for 8, 10, 12 hours/day for 6 weeks respectively. Following each bleaching session; the specimens were washed with deionized water and kept in artificial saliva. After the bleaching periods; the samples were prepared for examination with scanning electron microscope. X ray quantitative analysis of Calcium and Phosphorous atomic contents for enamel and dentine specimens was done at two standardized points [mesio-incisal and disto-incisal] for each; using the same scanning electron microscope. The results showed the following as regarding the enamel ultrastructure; exaggerated thickness of the prism boundaries and mild to moderate loss of hydroxyapatite crystals [erosion of the prisms] in the 1[st] and 2[nd] groups while in the 3[rd] group there was total loss of hydroxyapatite crystals leaving empty enamel rods. The dentine ultrastructure results showed blocking of some dentinal tubules in the 1[st] experimental group by a smear layer of the demineralized debris that filled the empty tubules. More narrowing of the dentinal tubules by these demineralized debris became more prominently increased from the 2[nd] to 3[rd] experimental group which appeared to be completely obliterated. The statistical results revealed an overall significant difference between the control and the three experimental groups for enamel and dentine atomic calcium and phosphorus contents. Thus, we can conclude that the effect of 16% concentration of carbamide peroxide bleaching gel was safety for enamel and dentine at 8 hours/day for 6 weeks [1[st] experimental group] and this must be considered the optimal time period for bleaching without adverse hazardous effects on enamel and dentine microstructures