The evolution of primary double-bundle ACL reconstruction and recovery of early post-operative range of motion.

PURPOSE: The aim of this study was to analyse early post-operative range of motion (ROM) as our anatomic double-bundle (DB) anterior cruciate (ACL) reconstruction technique with respect to tunnel placement evolved. It is the hypothesis of this study that more anatomic placement of the femoral insertion site of the anteromedial (AM) bundle of the ACL results in better restoration of early post-operative knee range of motion. METHODS: Two methods of DB ACL reconstruction regarding more accurate placement of the femoral AM tunnel in relation to its anatomic origin were compared. Patients presenting for 1- and 3-month post-operative clinical visits were examined for passive extension and active flexion by members of the clinical staff. Only patients undergoing primary DB reconstruction with allograft were included in the analyses. To determine the effects of the modified AM bundle placement on recovery of post-operative ROM, patients undergoing surgery in the 6 months before July 2006 (Group A, n = 50) were compared to patients undergoing surgery in the 6 months after July 2006 (Group B, n = 49). RESULTS: A total of 99 patients met the inclusion criteria. More accurate placement of the AM bundle of the ACL was associated with a smaller side-to-side difference in flexion at 1 month (n.s.) and at 3 months (3° reduction, p < 0.03) after surgery. There was no effect on extension (n.s.) CONCLUSION: More anatomic placement of the femoral insertion of the AM bundle was associated with improved knee flexion. The study translates the findings of previous anatomic basic science research to demonstrate improved restoration of normal joint motion. This ideally leads to improved long-term clinical outcomes and maintenance of joint and cartilage health. LEVEL OF EVIDENCE: III.

Dual-Energy CT of Incidental Findings in the Abdomen: Can We Reduce the Need for Follow-Up Imaging?

OBJECTIVE: The purpose of this article is to review the added value of dual-energy CT for characterization of incidental lesions discovered during routine abdominal CT. CONCLUSION: Dual-energy CT allows acquisition of virtual unenhanced images, iodine maps, and virtual monochromatic images, all of which can aid in characterizing incidental lesions at the time of detection. Virtual unenhanced images and iodine maps are used for assessment of enhancement of incidental lesions, which can help differentiate suspicious enhancing lesions from benign nonenhancing lesions. Virtual monochromatic images can be obtained at low energy to improve conspicuity and detection of subtle lesions. Routine use of dual-energy CT may eliminate the need for additional imaging in the workup of some of these incidental lesions.

Bone flap explantation, steroid use, and rates of infection in patients with epilepsy undergoing craniotomy for implantation of subdural electrodes.

OBJECT: Subdural implantation of electrodes is commonly performed to localize an epileptic focus. Whether to temporarily explant the bone plate and whether to treat patients with perioperative steroid agents is unclear. The authors' aim was to evaluate the utility and risk of bone plate explantation and perioperative steroid use. METHODS: The authors reviewed the records of all patients who underwent unilateral craniotomy for electrode implantation performed between November 2001 and June 2011 at their institution. Patients were divided into 3 groups: Group 1 (n=24), bone explanted, no perioperative steroid use; Group 2 (n=42), bone left in place, no perioperative steroid use; Group 3 (n=25), bone left in place, steroid agents administered perioperatively. Complications, mass effect, and seizure rates were examined by means of statistical analysis. RESULTS: Of 324 cranial epilepsy surgeries, 91 were unilateral subdural electrode implants that met our inclusion criteria. A total of 11 infections were reported, and there was a significantly higher rate of infection when the bone was explanted (8 cases [33.3%]) than when the bone was left in place (3 cases [4.5%], p<0.01). Leaving the bone in place also increased the rate of asymptomatic subdural hematomas and frequency of seizures, although there was no increase in midline shift, severity of headache, or rate of emergency reoperation. The use of steroid agents did not appear to have an effect on any of the outcome measures. CONCLUSIONS: Temporary bone flap explantation during craniotomy for implantation of subdural electrodes can result in high rates of infection, possibly due to the frequent change of hands in transferring the bone to the bone bank. Leaving the bone in place may increase the frequency of seizures and appearance of asymptomatic subdural hematomas but does not increase the rate of complications. These results may be institution dependent.

Diffusion-weighted imaging to assess treatment response in a child with trilateral retinoblastoma.

Trilateral retinoblastoma (TRb) is a rare condition in which children with bilateral retinoblastoma develop primary midline intracranial neuroblastic tumors. The intracranial lesions are difficult to follow after treatment due to residual mass-like enhancement that may represent persistent tumor or treated disease. We highlight a case where close evaluation of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) characteristics accurately depicted the extent of treated disease versus residual tumor after chemotherapy.