Minimally invasive far lateral tubular microdiscectomy: surgical technique and case series of 176 patients.

BACKGROUND: Far lateral (extraforaminal) disc herniations comprise approximately 10% of symptomatic lumbar disc herniations. They represent operative challenges due to accessibility and surgical unfamiliarity. Surgical strategies in the past have included open discectomy and posterior lumbar interbody fusion. Tubular microdiscectomies have gained traction due to their minimally invasive advantages, including reduced morbidity, pain and length of hospital stay. METHODS: We report our retrospective single institution consecutive case series of tubular far lateral microdiscectomies. One hundred and seventy-six patients were operated on over an eight-year period. Clinical outcomes were assessed after institutional ethics approval. We additionally describe our surgical technique with an illustrative video case. RESULTS: Over a mean follow-up of 21 weeks, 77% of patients had good or excellent clinical outcomes according to the MacNab criteria. 12% of patients underwent reoperation at the index level for symptom recurrence or persistence. Mean length of hospital stay was 1.3 days. There was a 1% rate of both postoperative haematoma and infection. Mean operation duration was 86 minutes. CONCLUSION: This case series represents the largest currently reported in the literature. Minimally invasive microdiscectomies performed through tubes allow for precise localisation, reduced tissue disruption and favourable clinical outcomes. Our results appear consistent with a review of the literature, demonstrating the safety and efficacy of this approach.

Remote cerebellar haemorrhage from site of craniotomy: A report of two cases.

Remote cerebellar haemorrhage (RCH) is a rare complication of neurosurgical procedures seldom requiring intervention. We report two cases of RCH. The first unilateral RCH is asymptomatic, the other is bilateral and associated with supratentorial haemorrhage and hydrocephalus requiring intervention. We propose multiple foci of haemorrhage as an adverse prognostic marker in RCH.

Minimally invasive transforaminal lumber interbody fusion and degenerative lumbar spine disease.

OBJECTIVE: The purpose of this study was to assess the clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) surgery for degenerative lumbar spine disease. METHODS: A prospective analysis of 34 consecutive patients who underwent a MI-TLIF using image guidance between July 2008 and November 2010. The patient group comprised 19 males and 15 females (mean age 56), 23 of whom had undergone additional reduction of spondylolisthesis. All patients underwent post-operative CT imaging to assess pedicle screw, cage placement and fusion at 6 months. Oswestry disability index (ODI) scores were recorded pre-operatively and at 6-month follow up. RESULTS: 33/34 (97.1%) patients showed evidence of fusion at 6 months with a mean improvement of 27 on ODI scores. The mean length of hospital stay was 4 days. The mean operative time was 173 min. COMPLICATIONS OBSERVED: 1/34 (2.9%) suffered a pulmonary embolism and 1/34 (2.9%) patients developed transient nerve root pain post-operatively. There were no occurrences of infection and no post-operative CSF leaks. CONCLUSION: MI-TLIF offers patients a safe and effective surgical treatment option to treat degenerative lumbar spine disease.

Osseous Sarcoidosis with a Solitary Lytic Skull Lesion: A Case Report.

Bone sarcoidosis is an uncommon manifestation of the multisystemic disease with skull involvement being rare. We present the case of a 32-year-old female who was referred by her General Practitioner with a left calvarial lesion on a background of previous unilateral 7th nerve palsy and diabetes mellitus. Images demonstrated a left frontoparietal calvarial osteolytic lesion. She underwent resection by the neurosurgical team with histopathological study revealing noncaseating granulomas, consistent with sarcoidosis. Given absence of other systemic features of sarcoidosis, she did not undergo systemic treatment.

Surgical risks associated with the management of Grade I and II brain arteriovenous malformations.

OBJECTIVE: Grade I and II arteriovenous malformations (AVMs) have been considered safe to resect. However, unoperated low-grade AVMs have not been considered in previously reported series. The aim of this study was to examine all cases, both operated and unoperated, to identify any characteristics of low-grade AVMs that comprise a subgroup that might pose a relatively higher risk. METHODS: A prospectively enrolled AVM database included 237 patients in Spetzler-Martin Grade I or II. These patients were analyzed on the basis of demographic characteristics, angiographic and magnetic resonance imaging features, clinical presentation, method of treatment, and outcome. RESULTS: Surgery was performed in 220 patients in Spetzler-Martin Grade I or II. Seventeen patients did not undergo treatment because of poor neurological condition (six patients), patient refusal (nine patients), and perceived surgical difficulty (AVM size approaching 3 cm adjacent to Broca's area) (two patients). The overall surgical morbidity rate was 0.9%, and the mortality rate was 0.5%. Adverse outcomes occurred in 1 (0.6%) of 180 patients with AVMs located away from eloquent cortex and in 2 (5%) of 40 patients with AVMs adjacent to eloquent cortex. None of 28 surgical patients with deep venous drainage had an adverse outcome. All 219 patients who survived surgery underwent postoperative angiography that confirmed cure. No postoperative hemorrhage has occurred in 1143 patient-years of follow-up (mean follow-up, 5.3 yr). CONCLUSION: When considering adverse outcome in the surgical series of Grade I and II AVMs alone, no statistical difference between non-eloquently located AVMs (0.6%) and eloquently located AVMs (5% adverse outcome) can be detected. However, consideration of all Grade I and II AVMs, both surgical and nonsurgical, may prove that a difference in outcome exists between these two groups masked by case selection. Generalization of the chances of adverse outcomes to all Grade I and II AVMs (both operated and unoperated) suggests that the risk of performing surgery on noneloquent brain in our series was 0.6% and that in eloquent brain could have been as high as 9.5%, had all such patients undergone surgery.

Complications from minimally invasive lumbar interbody fusion: experience from 100 patients.

Minimally invasive lumbar fusion is well described and is reported to offer significant advantages to patients in terms of blood loss, a reduction in post-operative pain and a quicker recovery. However, this technique may expose patients to a greater risk of complications when compared to open lumbar instrumented fusion that may negate these advantages. Between January 2007 and March 2001, we conducted a prospective observational study of 100 consecutive patients (48 males and 52 females, mean age of 54 years) to investigate complications occurring from minimally invasive lumbar interbody fusion surgery using an image-guided technique. All patients underwent post-operative CT scans to assess implant placement. Scanning was repeated at 6 months to assess bony fusion. We observed the following complications: 2.5% (11/435) pedicle screw misplacement, 1.7% (2/120) interbody cage misplacement; 0.8% (1/120) interbody cage migration; 0.8% (1/120) patients requiring a post-operative blood transfusion; 2% (2/100) venous thrombo-embolism and 3% (3/100) patients with complications thought to be related to the use of bone morphogenic protein. There were no occurrences of infection and no cerebrospinal fluid leaks. We concluded that the rate of complications from minimally invasive lumbar interbody fusion is low, and compares favourably with the rates of complication from open procedures. Moreover, computerised navigation systems can be used in place of real-time fluoroscopy to guide implant placement, without an increase in the rate of complications.

Minimally invasive transforaminal lumbar interbody fusion and spondylolisthesis.

The purpose of this study was to assess the clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) surgery for lumbar spondylolisthesis. A prospective analysis was conducted of 23 consecutive patients with grade I or grade II lumbar spondylolisthesis who underwent a MI-TLIF using image guidance between August 2008 and September 2010. The patient group comprised 13 males and 10 females (mean age 57 years), 22 of whom underwent single level fusion and one patient with a two level fusion. All patients underwent postoperative CT scans to assess pedicle screw and cage placement and fusion at six months. The Oswestry Disability Index (ODI) scores were recorded preoperatively and at the six-month follow-up. We found that 22 of 23 (95.7%) patients showed evidence of fusion at six months with a mean improvement of 26.7 on ODI scores. The mean length of hospital stay was four days. The mean operative time was 172 minutes. Anatomical reduction of the spondylolisthesis was complete in 16 patients and incomplete in seven. Regarding complications, we observed: one of 94 (1.1%) pedicle screws misplaced, which did not require revision postoperatively; one of 23 patients (4.3%) with a pulmonary embolism and one of 23 (4.3%) patients with transient nerve root pain. There were no occurrences of infection and no postoperative cerebrospinal fluid leaks. We conclude that MI-TLIF offers patients a safe and effective surgical option for lumbar spondylolisthesis treatment. Furthermore, it may offer patients additional advantages in terms of postoperative pain and recovery.

Surgical risks associated with the management of Grade I and II brain arteriovenous malformations.

OBJECTIVE: Grade I and II arteriovenous malformations (AVMs) have been considered safe to resect. However, unoperated low-grade AVMs have not been considered in previously reported series. The aim of this study was to examine all cases, both operated and unoperated, to identify any characteristics of low-grade AVMs that comprise a subgroup that might pose a relatively higher risk. METHODS: A prospectively enrolled AVM database included 237 patients in Spetzler-Martin Grade I or II. These patients were analyzed on the basis of demographic characteristics, angiographic and magnetic resonance imaging features, clinical presentation, method of treatment, and outcome. RESULTS: Surgery was performed in 220 patients in Spetzler-Martin Grade I or II. Seventeen patients did not undergo treatment because of poor neurological condition (six patients), patient refusal (nine patients), and perceived surgical difficulty (AVM size approaching 3 cm adjacent to Broca's area) (two patients). The overall surgical morbidity rate was 0.9%, and the mortality rate was 0.5%. Adverse outcomes occurred in 1 (0.6%) of 180 patients with AVMs located away from eloquent cortex and in 2 (5%) of 40 patients with AVMs adjacent to eloquent cortex. None of 28 surgical patients with deep venous drainage had an adverse outcome. All 219 patients who survived surgery underwent postoperative angiography that confirmed cure. No postoperative hemorrhage has occurred in 1143 patient-years of follow-up (mean follow-up, 5.3 yr). CONCLUSION: When considering adverse outcome in the surgical series of Grade I and II AVMs alone, no statistical difference between non-eloquently located AVMs (0.6%) and eloquently located AVMs (5% adverse outcome) can be detected. However, consideration of all Grade I and II AVMs, both surgical and nonsurgical, may prove that a difference in outcome exists between these two groups masked by case selection. Generalization of the chances of adverse outcomes to all Grade I and II AVMs (both operated and unoperated) suggests that the risk of performing surgery on noneloquent brain in our series was 0.6% and that in eloquent brain could have been as high as 9.5%, had all such patients undergone surgery.