Presurgical assessment and surgical treatment for epilepsy

In the last ten years, dramatic advances in surgical treatment options and techniques have allowed surgical intervention for patients who would otherwise not have been considered as surgical candidates. In this article, a multidisciplinary, logical decision algorithm for a rational approach to surgical treatments is outlined. A carefully considered hierarchy is presented that provides for maximized seizure improvement outcomes. Topics presented include temporal lobectomy, detailed discussion of dominant temporal lobectomy and speech-sparing techniques, neocortical resection, the use of subdural electrode array, depth electrodes, and strip electrodes, multiple subpinal transection, vagus nerve stimulation, and corpus callosotomy. The application of these various techniques to maximize surgical outcome are discussed.     

Visual outcome following penetrating globe injuries with retained intraocular foreign bodies

BACKGROUND: In our institution the occurrence of endophthalmitis related to intraocular foreign bodies has been rare. In this review we analyse the outcome of eyes with retained intraocular foreign bodies presenting to two vitreoretinal surgeons over nearly 7 years. METHODS: Review of the records of 26 patients who presented to two surgeons in a tertiary care vitreoretinal service in Toronto between January 1989 and November 1995. Information documented included mechanism of injury, time from injury to definitive surgery, entry site, presence of vitreous hemorrhage, type of surgery performed, initial and final visual acuity, and development of endophthalmitis. RESULTS: All the injuries occurred in male patients, with a mean age of 36.1 (range 15 to 55) years. Most of the injuries occurred in the workplace, and in most cases (17 [65.4%]) the mechanism of injury was "metal on metal." The entry site was via a perforating wound of the cornea in 16 cases (61.5%). Almost all cases were repaired within 48 hours by means of pars plana vitrectomy. Concurrent lensectomy was required in 18 cases (69.2%) for lens damage at the time of the original injury. Vitreous hemorrhage was present in 22 cases (84.6%). One patient (3.8%) manifested clinically apparent endophthalmitis, which responded to intravitreal antibiotic therapy. Nineteen eyes (73.1%) had a final visual acuity of 6/24 or better. Eyes with coexisting or subsequent retinal detachment had significantly worse vision than those without retinal detachment (p < 0.001). INTERPRETATION: The incidence of endophthalmitis in our series is lower than that in other published series. Prompt definitive treatment was associated with a good prognosis in most cases.     

Effect of partial hepatectomy on the expression of seven rat sulphotransferase mRNAs.

1. The effect of partial hepatectomy on the expression of sulphotransferase (SULT) mRNA was studied. SULTs fall into two distinct classes based on substrate preference: phenol SULT1 family (SULT1A1, SULT1B1, SULT1C1 and SULT1E2) and hydroxysteroid SULT2 family (SULT20/21, SULT40/41 and SULT60). 2. Hepatic expression of SULT mRNA was analysed in the sham-hepatectomised rat (sham) and in the partially hepatectomised (PH) rat at various times after PH. Northern-blot analysis with [alpha-32P]dATP-labelled oligonucleotide probes specific for individual SULT mRNAs was used to monitor hepatic SULT mRNA expression. In general, SULT mRNAs underwent a decrease in expression after PH and the magnitude of decrease was dependent on the SULT isoform. 3. The decrease in SULT mRNA expression was resolved and even induced (SULT40/41 in the female rat) by 10-30 days after PH. Of the phenol SULT isoforms, both SULT1C1 and SULT1E2 mRNAs were significantly decreased by 18-24 h after PH in the male rat. The other phenol SULTs (SULT1A1 and SULT1B1) tended to decrease in the male rat after PH, but the decreases were not statistically significant. Expression of SULT20/21 mRNA was decreased in the female rat (80% at 24 h) and fully recovered by 10 days. SULT40/41 mRNA tended to decrease after PH; however, the decrease was not statistically significant. SULT 60 mRNA was decreased from 24 to 96 h after PH. 4. Thus, during the period of rapid liver growth that occurs after partial hepatectomy, SULT mRNA expression is decreased. The phenomenon of decreased SULT mRNA expression is similar to other states of rapid liver growth (e.g. cancer tissue and young animals) in which expression of SULT enzymes is characteristically low.     

Breast implant materials: sense and safety.

Cosmetic breast augmentation, and post-mastectomy breast reconstruction surgery using synthetic implants, have become established in surgical practice over more than 20 years. The operative technique for implant placement have changed somewhat during this time, as many different implant presentations have become available, but the same basic materials have remained in use. We have reviewed the present state of knowledge about breast implant materials with particular reference to the possible connection between polydimethylsiloxane and polyurethane to the so-called "Human Adjuvant Disease", and to carcinogenesis. Problems related to capsular contracture and mammography are also discussed.     

Mechanisms of graft versus host disease produced by small bowel transplantation

Mechanisms of graft versus host disease have been studied in Lew x BN animals transplanted with a Lew small bowel. Grafted mesenteric lymph nodes but not host mesenteric lymph nodes or host spleen, in small bowel transplanted rats undergoing lethal GVHD, provide a source of CTL with specific anti-recipient cytotoxic activity. Host MLN and host spleen display anti-recipient CTL activity only when GVHD is provoked by intraperitoneal lymphocyte injection. These data demonstrate that lethal GVHD after SBTx may occur in the absence of detectable cytotoxic activity in host lymphoid tissues, suggesting that other mechanisms are involved in the pathogenesis of GVHD after SBTx. GVHD after SBTx or lymphocyte transfer is associated with the appearance of TNF in the serum. The intensity and reversibility of this phenomenon correlate with both the clinical severity and the lethality of GVHD. Taken together these data highly suggest that TNF is directly involved in the pathogenesis of GVHD after SBTx.     

Prosthetic arteriovenous fistula for vascular access in hemodialysis.

Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.     

Head injury in the severely injured: long-term follow-up in 157 patients

Ninety-two patients with head injury in the context of multiple injury were followed up 5 years after injury. Severe disability in this group of patients was nearly always due to brain/spinal cord injury, rather than musculoskeletal injury. A substantial number of patients with mild or moderate head injuries had significant persisting disability 5 years after injury.