Tibial tunnel placement in posterior cruciate ligament reconstruction: a systematic review.

PURPOSE: Reconstruction of the posterior cruciate ligament (PCL) yields less satisfying results than anterior cruciate ligament reconstruction with respect to laxity control. Accurate tibial tunnel placement is crucial for successful PCL reconstruction using arthroscopic tibial tunnel techniques. A discrepancy between anatomical studies of the tibial PCL insertion site and surgical recommendations for tibial tunnel placement remains. The objective of this study was to identify the optimal placement of the tibial tunnel in PCL reconstruction based on clinical studies. METHODS: In a systematic review of the literature, MEDLINE, EMBASE, Cochrane Review, and Cochrane Central Register of Controlled Trials were screened for articles about PCL reconstruction from January 1990 to September 2011. Clinical trials comparing at least two PCL reconstruction techniques were extracted and independently analysed by each author. Only studies comparing different tibial tunnel placements in the retrospinal area were included. RESULTS: This systematic review found no comparative clinical trial for tibial tunnel placement in PCL reconstruction. Several anatomical, radiological, and biomechanical studies have described the tibial insertion sites of the native PCL and have led to recommendations for placement of the tibial tunnel outlet in the retrospinal area. However, surgical recommendations and the results of morphological studies are often contradictory. CONCLUSIONS: Reliable anatomical landmarks for tunnel placement are lacking. Future randomized controlled trials could compare precisely defined tibial tunnel placements in PCL reconstruction, which would require an established mapping of the retrospinal area of the tibial plateau with defined anatomical and radiological landmarks.

Evaluation of an intravitreal fluocinolone acetonide implant versus standard systemic therapy in noninfectious posterior uveitis.

PURPOSE: To evaluate the safety and efficacy of an intravitreal fluocinolone acetonide (FA) implant compared with standard therapy in subjects with noninfectious posterior uveitis (NIPU). DESIGN: Randomized, controlled, phase 2b/3, open-label, multicenter superiority trial. PARTICIPANTS: Subjects with unilateral or bilateral NIPU. METHODS: One hundred forty subjects received either a 0.59-mg FA intravitreal implant (n = 66) or standard of care (SOC; n = 74) with either systemic prednisolone or equivalent corticosteroid as monotherapy (> or =0.2 mg/kg daily) or, if judged necessary by the investigator, combination therapy with an immunosuppressive agent plus a lower dose of prednisolone or equivalent corticosteroid (> or =0.1 mg/kg daily). MAIN OUTCOME MEASURES: Time to first recurrence of uveitis. RESULTS: Eyes that received the FA intravitreal implant experienced delayed onset of observed recurrence of uveitis (P<0.01) and a lower rate of recurrence of uveitis (18.2% vs. 63.5%; P< or =0.01) compared with SOC study eyes. Adverse events frequently observed in implanted eyes included elevated intraocular pressure (IOP) requiring IOP-lowering surgery (occurring in 21.2% of implanted eyes) and cataracts requiring extraction (occurring in 87.8% of phakic implanted eyes). No treatment-related nonocular adverse events were observed in the implant group, whereas such events occurred in 25.7% of subjects in the SOC group. CONCLUSIONS: The FA intravitreal implant provided better control of inflammation in patients with uveitis compared with systemic therapy. Intraocular pressure and lens clarity of implanted eyes need close monitoring in patients receiving the FA intravitreal implant.

Traitement des plagiocéphalies postérieures d'origine positionnelle [Treatment of posterior positional plagiocephaly]

In 1992, the American academy of paediatrics has recommended that infants be placed on their backs to sleep, because prone sleeping has been correlated with sudden infant death syndrome. Following this article, medical paediatric community has documented an exponential increase in the diagnosis of posterior cranial deformities, which were considered as the consequence of unrelieved pressure onto the occiput during infant sleep. These last 15 years, management of posterior positional plagiocephaly has evolved but is still not standardized; it varies according to local specificities, and medical or parental preferences. Treatment of deformational plagiocephaly includes preventive counseling, repositioning adjustments and exercises, physiotherapy, osteopathy, treatment by dynamic cranial orthosis. On extremely rare occasions, corrective surgery is proposed. This article aims at reviewing the epidemiologic, diagnostic, and various therapeutic options of posterior positional plagiocephaly.

Interhemispheric coupling between the posterior sylvian regions impacts successful auditory temporal order judgment.

Accurate perception of the temporal order of sensory events is a prerequisite in numerous functions ranging from language comprehension to motor coordination. We investigated the spatio-temporal brain dynamics of auditory temporal order judgment (aTOJ) using electrical neuroimaging analyses of auditory evoked potentials (AEPs) recorded while participants completed a near-threshold task requiring spatial discrimination of left-right and right-left sound sequences. AEPs to sound pairs modulated topographically as a function of aTOJ accuracy over the 39-77ms post-stimulus period, indicating the engagement of distinct configurations of brain networks during early auditory processing stages. Source estimations revealed that accurate and inaccurate performance were linked to bilateral posterior sylvian regions activity (PSR). However, activity within left, but not right, PSR predicted behavioral performance suggesting that left PSR activity during early encoding phases of pairs of auditory spatial stimuli appears critical for the perception of their order of occurrence. Correlation analyses of source estimations further revealed that activity between left and right PSR was significantly correlated in the inaccurate but not accurate condition, indicating that aTOJ accuracy depends on the functional decoupling between homotopic PSR areas. These results support a model of temporal order processing wherein behaviorally relevant temporal information--i.e. a temporal 'stamp'--is extracted within the early stages of cortical processes within left PSR but critically modulated by inputs from right PSR. We discuss our results with regard to current models of temporal of temporal order processing, namely gating and latency mechanisms.

Left temporal lobe epilepsy revealing left posterior cortical atrophy due to Alzheimer's disease.

Seizures can be an early symptom of Alzheimer's disease (AD) and can precede cognitive decline. Early epilepsy in AD can mimic transient epileptic amnesic syndrome (TEAS) or epileptic amnesic syndrome. We report the case of a patient who started a cerebrospinal fluid (CSF)-proven AD with partial seizures and TEAS that secondarily became a cortical posterior atrophy syndrome. CSF biomarkers showed a high amyloid production, amyloidopathy, and high level of total tau and p-Tau. This observation adds data to the complex AD-early epilepsy interactions and illustrates that atypical AD can cause a TEAS. Possible red flags for an underlying neurodegenerative process in TEAS are discussed.

Cerebral Hypoperfusion in Posterior Reversible Encephalopathy Syndrome is Different from Transient Ischemic Attack on CT Perfusion.

BACKGROUND: PRES is a reversible neurotoxic state presenting with headache, altered mental status, visual loss, and seizures. Delayed diagnosis can be avoided if radiological patterns could distinguish PRES from cerebral ischemia. METHODS: Clinical and radiological data were collected on all hospitalized patients who had (1) discharge diagnosis of PRES and (2) acute CTP/CTA. Data were compared with 10 TIA patients with proven cytotoxic edema on MRI. RESULTS: Of the four PRES patients found, three were correlated with acute blood pressure and one with chemotherapy. At the radiological level, quantitative analyses of the CTP parameters showed that 2 out of 4 patients had bilaterally reduced CBF-values (23.2-47.1 ml/100g/min) in occipital regions, as seen in the pathological regions of TIA patients (27.3 ± 13.5 ml/100g/min). When compared with TIA patients, the pathological ROI's demonstrated decreased CBV-values (3.4-5.6 ml/100g). Vasogenic edema on MRI FLAIR imaging was seen in only one PRES patient, and cytotoxic edema on DWI-imaging was never found. CT angiography showed in one PRES patient a vasospasm-like unilateral posterior cerebral artery. CONCLUSIONS: If confirmed by other groups, CTP and CTA imaging in patients with acute visual loss and confusion may help to distinguish PRES from bi-occipital ischemia. These radiological parameters may identify PRES patients at risk for additional tissue infarction.

Posterior Sub-Tenon Triamcinolone Injection for Chronic Macular Oedema Associated With Non-Ischemic Branch or Central Retinal Vein Occlusion

Aims: To evaluate the effectiveness and safety of Posterior Sub-Tenon (PST) Triamcinolone Acetonide (TA) injection for persistent macular oedema associated with non-ischemic Central Retinal Vein Occlusion (CRVO) or Branch Retinal Vein Occlusion (BRVO) in non-vitrectomized eye. Methods: Fourteen consecutive eyes of 14 patients characterized by macular oedema lasting more than 3 months and with a visual acuity of less than 20/40 were enrolled. Six eyes presented with BRVO, 8 eyes with CRVO. PST injection of 40 mg TA was performed in topical anaesthesia. All patients were phakic, and followed for at least 6 months. Snellen visual acuity converted to LogMAR units and anatomic responses were evaluated before, and at 1, 3, 6, and 12 (if required) months after injections and re-injection considered. Results: In the BRVO group, mean foveal thickness was 548.2±49.50 μm preoperatively, and 452.8±56.2 μm and 280.8±62.5 μm at 1 and 12 month follow-up, respectively. Statistical analysis showed significant differences between preoperative and postoperative measurements (P<.05, paired t test) 3 months after injections. Improvement of visual acuity by at least 0.2 LogMAR was seen in 3(50%) of the 6 eyes. No re-injection was needed. In the CRVO group, mean foveal thickness was 543.7±34.4 μm preoperatively, and 283.0±29.0 μm and 234.8±23.6 μm at 1 and 12 month follow-up, respectively. Statistical analysis showed significant differences between preoperative and postoperative measurements (P<.05, paired t test). Improvement of visual acuity by at least 0.2 LogMAR was seen in 7 eyes (88%). Mean number of re-injection was of 2.1±0.3. Intraocular pressure elevation of 22 mm Hg or higher was found in 2/14 eyes (14%). Cataract progression was noted in 5/14 eyes (36%). Conclusions: PST injection of TA appears to be as safe and effective treatment for chronic macular oedema associated due to both non-ischemic BRVO or CRVO, with a better efficacy in BRVO.