From the Occipital Condyle to the Sphenoid Sinus: Extradural Extension of the Far Lateral Transcondylar Approach with Endoscopic Assistance

Step-by-Step Dissection of the Extreme Lateral Transodontoid Approach to the Anterior Craniovertebral Junction: Surgical Anatomy and Technical Nuances

BACKGROUND

Multicompartmental lesions of the anterior craniovertebral junction require aggressive management. However, the lesions can be difficult to reach, and the surgical procedure is difficult to understand. The aim of this study was to create a procedural, stepwise microsurgical educational resource for junior trainees to learn the surgical anatomy of the extreme lateral transodontoid approach (ELTOA).

METHODS

Ten formalin-fixed, latex-injected cadaveric heads were dissected under an operative microscope. Dissections were performed under the supervision of a skull base fellowship-trained neurosurgeon who has advanced skull base experience. Key steps of the procedure were documented with a professional camera and a high-definition video system. A relevant clinical case example was reviewed to highlight the principles of the selected approach and its application. The clinical case example also describes a rare complication: a pseudoaneurysm of the vertebral artery.

RESULTS

Key steps of the ELTOA include patient positioning, skin incision, superficial and deep muscle dissection, vertebral artery dissection and transposition, craniotomy, clivus drilling, odontoidectomy, and final extradural and intradural exposure.

CONCLUSIONS

The ELTOA is a challenging approach, but it allows for significant access to the anterior craniovertebral junction, which increases the likelihood of gross total lesion resection. Given the complexity of the approach, substantial training in the dissection laboratory is required to develop the necessary anatomic knowledge and to minimize approach-related morbidity.

Management strategies in clival and craniovertebral junction chordomas: a 29-year experience

OBJECTIVE

Chordomas represent one of the most challenging subsets of skull base and craniovertebral junction (CVJ) tumors to treat. Despite extensive resection followed by proton-beam radiation therapy, the recurrence rate remains high, highlighting the importance of developing efficient treatment strategies. In this study, the authors present their experience in treating clival and CVJ chordomas over a 29-year period.

METHODS

The authors conducted a retrospective study of clival and CVJ chordomas that were surgically treated at their institution from 1991 to 2020. This study focuses on three aspects of the management of these tumors: the factors influencing the extent of resection (EOR), the predictors of survival, and the outcomes of the endoscopic endonasal approaches (EEAs) compared with open approaches (OAs).

RESULTS

A total of 265 surgical procedures were performed in 210 patients, including 123 OAs (46.4%) and 142 EEAs (53.6%). Tumors that had an intradural extension (p = 0.03), brainstem contact (p = 0.005), cavernous sinus extension (p = 0.004), major artery encasement (p = 0.01), petrous apex extension (p = 0.003), or high volume (p = 0.0003) were significantly associated with a lower EOR. The 5-year progression-free survival (PFS) and overall survival (OS) rates were 52.1% and 75.1%, respectively. Gross-total resection and Ki-67 labeling index < 6% were considered to be independent prognostic factors of longer PFS (p = 0.0005 and p = 0.003, respectively) and OS (p = 0.02 and p = 0.03, respectively). Postoperative radiation therapy correlated independently with a longer PFS (p = 0.006). Previous surgical treatment was associated with a lower EOR (p = 0.01) and a higher rate of CSF leakage after EEAs (p = 0.02) but did not have significantly lower PFS and OS compared with primary surgery. Previously radiation therapy correlated with a worse outcome, with lower PFS and OS (p = 0.001 and p = 0.007, respectively). EEAs were more frequently used in patients with upper and middle clival tumors (p = 0.002 and p < 0.0001, respectively), had a better rate of EOR (p = 0.003), and had a lower risk of de novo neurological deficit (p < 0.0001) compared with OAs. The overall rate of postoperative CSF leakage after EEAs was 14.8%.

CONCLUSIONS

This large study showed that gross-total resection should be attempted in a multidisciplinary skull base center before providing radiation therapy. EEAs should be considered as the gold-standard approach for upper/middle clival lesions based on the satisfactory surgical outcome, but OAs remain important tools for large complex chordomas.

Endoscope-assisted far-lateral transcondylar approach for craniocervical junction chordomas: a retrospective case series and cadaveric dissection

OBJECTIVE

Craniocervical junction (CCJ) chordomas are a neurosurgical challenge because of their deep localization, lateral extension, bone destruction, and tight relationship with the vertebral artery and lower cranial nerves. In this study, the authors present their surgical experience with the endoscope-assisted far-lateral transcondylar approach (EA-FLTA) for the treatment of CCJ chordomas, highlighting the advantages of this corridor and the integration of the endoscope to reach the anterior aspect and contralateral side of the CCJ and the possibility of performing occipitocervical fusion (OCF) during the same stage of surgery.

METHODS

Nine consecutive cases of CCJ chordomas treated with the EA-FLTA between 2013 and 2020 were retrospectively reviewed. Preoperative characteristics, surgical technique, postoperative results, and clinical outcome were analyzed. A cadaveric dissection was also performed to clarify the anatomical landmarks.

RESULTS

The male/female ratio was 1.25, and the median age was 36 years (range 14-53 years). In 6 patients (66.7%), the lesion showed a bilateral extension, and 7 patients (77.8%) had an intradural extension. The vertebral artery was encased in 5 patients. Gross-total resection was achieved in 5 patients (55.6%), near-total resection in 3 (33.3%), and subtotal resection 1 (11.1%). In 5 cases, the OCF was performed in the same stage after tumor removal. Neither approach-related complications nor complications related to tumor resection occurred. During follow-up (median 18 months, range 5-48 months), 1 patient, who had already undergone treatment and radiotherapy at another institution and had an aggressive tumor (Ki-67 index of 20%), showed tumor recurrence at 12 months.

CONCLUSIONS

The EA-FLTA provides a safe and effective corridor to resect extensive and complex CCJ chordomas, allowing the surgeon to reach the anterior, lateral, and posterior portions of the tumor, and to treat CCJ instability in a single stage.

Classic cardiovascular risk factors improve in very elderly hypopituitary patients treated on standard hormone replacement in long term follow- up

Background

Hypopituitarism in the elderly population is an underdiagnosed condition and may increase comorbidities related to glucose metabolism, dyslipidemia, and cardiovascular risk factors. Optimization of hormone replacement that considers alterations in clearance rates of hormones, interaction with other medications, and evaluation of the risk-benefit ratio of treatment is a big challenge for clinical practice.

Objectives

This study aimed to evaluate classic cardiovascular risk factors in hypopituitary septuagenarians and octagenarians by diagnosis and after long-term hormone replacement.

Methods

This is a retrospective observational study, with patients recruited and selected from a registry in a tertiary medical center. We included patients aged 70–99 years with hypopituitarism, evaluated hormonal and biochemical parameters, and cardiovascular risk scores were calculated by diagnosis and compared after long-term follow-up. All patients gave informed consent. Patient data were compared to a sex and age-matched control group, with long-term geriatric follow-up, without endocrine diseases.

Results

Thirty-five patients were included, 16 patients aged 70–75 years (72.61), 12 patients 76–80 years (72.28), 7 patients 81–99 years (89.28). Pituitary macroadenomas were the main cause of hypopituitarism, mean maximal diameter 3.4 cm (2.9–4.3), and invasive craniopharyngiomas. At the moment of diagnosis, most patients were overweight, and abdominal adiposity was observed in 76.9% of women and 36.4% of men, primarily in octagenarians and nonagenarians. Comorbidities were frequent; 85.7% presented hypertension, 37.1% diabetes, 53.1% low HDL, 51.5% hypertriglyceridemia. Most patients presented more than two combined pituitary deficiencies; hypogonadism in 88.6%, central hypothyroidism in 82.9%, GH deficiency in 65.7%, and adrenal insufficiency in 25.7%. Analysis of cardiovascular risk prediction in the total cohort showed that 57.1% of patients presented a reduction in the General Cardiovascular Disease (CVD) Risk Prediction Score and 45.7% in atherosclerotic CVD risk estimated by ACC/AHA 2013 Pooled Cohort Equation, despite being submitted to conventional hormone replacement, during the mean follow-up of 14.5 years. This reduction was not observed in the control group.

Discussion and conclusion

In this study, aged hypopituitary patients presented a reduction in estimated general CVD risk during long-term follow-up, despite replacement with corticosteroids, levothyroxine, or gonadal steroids. Early diagnosis and treatment of hypopituitarism in the elderly remain challenging. Larger studies should be performed to assess the risk-benefit ratio of hormone replacement on the metabolic profile in septuagenarian and octogenarian patients.