MRI predictors of revision surgery after primary lumbar discectomy.

The prognostic significance of preoperative MRI findings in patients undergoing discectomy is incompletely understood. Identifying the radiological predictors of revision surgery on pre-operative MRI can guide management decisions and potentially prevent multiple surgeries. We included 181 patients who underwent primary lumbar discectomy between 2010 and 2014. All patients were contacted via a short telephone interview to determine if they had revision surgery within 5 years of their index surgery. Preoperative MRI of the lumbosacral spine was evaluated for various radiological factors including type of disc herniation, anatomical location of herniation, direction of herniation, degree of disc degeneration, end plate changes and presence of listhesis. Other potential confounders including age, gender, smoking status and index level of surgery were also recorded. Multivariate model of all radiological predictors and confounders were developed and a step-wise approach was used to remove insignificant variables in order to develop final significant multivariate model. P value of <0.05 was considered statistically significant. Patients with retrolisthesis were found to be 2.7 times more likely than the patients without listhesis to require revision surgery (p = 0.019). Patients with foraminal disc herniation were 3.45 times more likely than the patients with paramedian disc herniation to require revision surgery (p = 0.026). Other MRI predictors failed to achieve statistical significance. Based on the data presented patients with retrolisthesis and/or foraminal disc herniation should be counselled on the relatively higher risk of revision surgery when proceeding with discectomy, or alternative options should be considered.

Radiological predictors of recurrent lumbar disc herniation: a systematic review and meta-analysis.

OBJECTIVE: Lumbar discectomy for the management of lumbar radiculopathy is a commonly performed procedure with generally excellent patient outcomes. However, recurrent lumbar disc herniation (rLDH) remains one of the most common complications of the procedure, often necessitating repeat surgery. rLDH is known to be influenced by a variety of factors, and in this systematic review the authors aimed to explore the radiological predictors of recurrence. METHODS: A systematic review and meta-analysis was conducted to identify studies analyzing radiological predictors of recurrent herniation, both ipsilateral and contralateral. A search was conducted on Medline and EMBASE. Both retrospective and prospective comparative studies were included, measuring radiological parameters of lumbar discectomy patients. All factors were considered irrespective of imaging modality, and a meta-analysis of the data was performed in which 5 or more studies were identified analyzing the same parameter. RESULTS: In total, 1626 reported studies were screened, with 23 being included in this review, of which 13 were appropriate for meta-analysis. Three factors, namely disc height index, Modic changes, and sagittal range of motion, were determined to be significantly correlated with an increased rate of rLDH. Some variables were considered in only 1 or 2 different studies, and the authors have included a narrative review of these novel findings. CONCLUSIONS: The findings of associations between the radiological parameters and rLDH implicates the role of instability in the development of recurrence. Understanding the physiological factors associated with instability is important, because although early degenerative disc changes may predispose patients to herniation recurrence, more advanced degeneration likely reduces segmental motion and concurrently risk of recurrence.

Endoscopic Fenestration of a Symptomatic Porencephalic Cyst in an Adult.

A porencephalic cyst is an aberrant accumulation of cerebrospinal fluid within the brain parenchyma. Its occurrence is rare, with an incidence of 3.5 per 100,000 live births. Etiology is considered the result of perinatal cerebral ischemia or hemorrhage, leading to parenchymal loss. Porencephalic cysts are diagnosed radiologically, and management depends on the clinical manifestation. Our case depicts a porencephalic cyst presenting with nondominant parietal lobe symptoms in adulthood. We hypothesize that a membrane between the cyst and ventricle allowed formation of a 1-way valve that led to slowly progressive cyst enlargement, eventually causing mass effect and nondominant parietal lobe symptoms. Endoscopic fenestration of the cyst membrane into the lateral ventricle was successful in reducing cyst volume and improving mass effect.

Extended maxillotomy for skull base access in contemporary management of chordomas: Rationale and technical aspect.

Minimally invasive approaches to the central skull base have been popularized over the last decade and have to a large extent displaced 'open' procedures. However, traditional skull base surgery still has its role especially when dealing with a large clival chordoma where maximal surgical resection is the principal goal to maximize patient survival. In this paper, we present a case of a 25year-old male patient with chordoma in the inferior clivus which was initially debulked via a transnasal endoscopic approach. He unfortunately had a large recurrence of tumor requiring re-do resection. With the aim to achieve maximal surgical resection, we then chose the technique of a transoral approach with Le Fort 1 maxillotomy and midline palatal split. Post-operative course for the patient was uneventful and post-operative MRI confirmed significant debulking of the clival lesion. The technique employed for the surgical procedure is presented here in detail as is our experience over two decades using this technique for tumors, inflammatory lesions and congenital abnormalities at the cranio-cervical junction.

Spontaneous pneumocephalus from nasal continuous positive airway pressure in a patient with ventriculo-peritoneal shunt.

Pneumocephalus in patients receiving positive airway pressure ventilation commonly occurs in the setting of trauma or surgery. We report a case of atraumatic pneumocephalus in a patient with a ventriculoperitoneal (VP) shunt on nasal continuous positive airway pressure (CPAP) for obstructive sleep apnoea. The patient presented with a 1-week history of "gurgling" sensation in his head and ataxia, with CT scan findings of a significant pneumocephalus. As extensive work up did not reveal any cause for his pneumocephalus, the nasal CPAP was thought to be the source. The CPAP was discontinued with improvement of the pneumocephalus, and resolution of his symptoms. He subsequently represented with recurrence of his symptoms, and increasing pneumocephalus on imaging. This was successfully managed by increasing his shunt pressure.

Congenital biparietal foramina presenting with multiple concussions.

We report a man with biparietal foramina secondary to Potocki-Shaffer syndrome. This is due to incomplete ossification of parietal bones secondary to haploinsuffiency of ALX4 gene. He presented with multiple episodes of concussion following minimal head trauma. Cranioplasty was performed to close the skull defects with the aim of preventing further concussion and permanent traumatic brain injury.

Is that lumbar disc symptomatic? Herniated lumbar disc associated with contralateral radiculopathy.

Herniated lumbar disc may be asymptomatic or associated with lower limb radiculopathy. Most spinal surgeons would offer surgery following a period of conservative measures if the radiological and clinical findings correlate. However, the existing dictum that lumbar radiculopathy should correlate with ipsilateral lumbar disc herniation may not be accurate as it can rarely present with contralateral sciatica. Literature regarding this phenomenon is scarce. Therefore, we report a patient with herniated lumbar disc presenting with predominantly contralateral motor weakness radiculopathy, which resolved after discectomy.